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third-party-mirror/openjdk/jdk25u/HEAD/./src/hotspot/cpu/aarch64/macroAssembler_aarch64.cpp
blob: a424bd7f275fbe6835c6ea9bb7e366f1d9555ff1 [file]
/*
* Copyright (c) 1997, 2025, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 2014, 2024, Red Hat Inc. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*
*/
#include "asm/assembler.hpp"
#include "asm/assembler.inline.hpp"
#include "ci/ciEnv.hpp"
#include "code/compiledIC.hpp"
#include "compiler/compileTask.hpp"
#include "compiler/disassembler.hpp"
#include "compiler/oopMap.hpp"
#include "gc/shared/barrierSet.hpp"
#include "gc/shared/barrierSetAssembler.hpp"
#include "gc/shared/cardTableBarrierSet.hpp"
#include "gc/shared/cardTable.hpp"
#include "gc/shared/collectedHeap.hpp"
#include "gc/shared/tlab_globals.hpp"
#include "interpreter/bytecodeHistogram.hpp"
#include "interpreter/interpreter.hpp"
#include "interpreter/interpreterRuntime.hpp"
#include "jvm.h"
#include "memory/resourceArea.hpp"
#include "memory/universe.hpp"
#include "nativeInst_aarch64.hpp"
#include "oops/accessDecorators.hpp"
#include "oops/compressedKlass.inline.hpp"
#include "oops/compressedOops.inline.hpp"
#include "oops/klass.inline.hpp"
#include "runtime/continuation.hpp"
#include "runtime/icache.hpp"
#include "runtime/interfaceSupport.inline.hpp"
#include "runtime/javaThread.hpp"
#include "runtime/jniHandles.inline.hpp"
#include "runtime/sharedRuntime.hpp"
#include "runtime/stubRoutines.hpp"
#include "utilities/globalDefinitions.hpp"
#include "utilities/powerOfTwo.hpp"
#ifdef COMPILER1
#include "c1/c1_LIRAssembler.hpp"
#endif
#ifdef COMPILER2
#include "oops/oop.hpp"
#include "opto/compile.hpp"
#include "opto/node.hpp"
#include "opto/output.hpp"
#endif
#include <sys/types.h>
#ifdef PRODUCT
#define BLOCK_COMMENT(str) /* nothing */
#else
#define BLOCK_COMMENT(str) block_comment(str)
#endif
#define STOP(str) stop(str);
#define BIND(label) bind(label); BLOCK_COMMENT(#label ":")
#ifdef ASSERT
extern "C" void disnm(intptr_t p);
#endif
// Target-dependent relocation processing
//
// Instruction sequences whose target may need to be retrieved or
// patched are distinguished by their leading instruction, sorting
// them into three main instruction groups and related subgroups.
//
// 1) Branch, Exception and System (insn count = 1)
// 1a) Unconditional branch (immediate):
// b/bl imm19
// 1b) Compare & branch (immediate):
// cbz/cbnz Rt imm19
// 1c) Test & branch (immediate):
// tbz/tbnz Rt imm14
// 1d) Conditional branch (immediate):
// b.cond imm19
//
// 2) Loads and Stores (insn count = 1)
// 2a) Load register literal:
// ldr Rt imm19
//
// 3) Data Processing Immediate (insn count = 2 or 3)
// 3a) PC-rel. addressing
// adr/adrp Rx imm21; ldr/str Ry Rx #imm12
// adr/adrp Rx imm21; add Ry Rx #imm12
// adr/adrp Rx imm21; movk Rx #imm16<<32; ldr/str Ry, [Rx, #offset_in_page]
// adr/adrp Rx imm21
// adr/adrp Rx imm21; movk Rx #imm16<<32
// adr/adrp Rx imm21; movk Rx #imm16<<32; add Ry, Rx, #offset_in_page
// The latter form can only happen when the target is an
// ExternalAddress, and (by definition) ExternalAddresses don't
// move. Because of that property, there is never any need to
// patch the last of the three instructions. However,
// MacroAssembler::target_addr_for_insn takes all three
// instructions into account and returns the correct address.
// 3b) Move wide (immediate)
// movz Rx #imm16; movk Rx #imm16 << 16; movk Rx #imm16 << 32;
//
// A switch on a subset of the instruction's bits provides an
// efficient dispatch to these subcases.
//
// insn[28:26] -> main group ('x' == don't care)
// 00x -> UNALLOCATED
// 100 -> Data Processing Immediate
// 101 -> Branch, Exception and System
// x1x -> Loads and Stores
//
// insn[30:25] -> subgroup ('_' == group, 'x' == don't care).
// n.b. in some cases extra bits need to be checked to verify the
// instruction is as expected
//
// 1) ... xx101x Branch, Exception and System
// 1a) 00___x Unconditional branch (immediate)
// 1b) 01___0 Compare & branch (immediate)
// 1c) 01___1 Test & branch (immediate)
// 1d) 10___0 Conditional branch (immediate)
// other Should not happen
//
// 2) ... xxx1x0 Loads and Stores
// 2a) xx1__00 Load/Store register (insn[28] == 1 && insn[24] == 0)
// 2aa) x01__00 Load register literal (i.e. requires insn[29] == 0)
// strictly should be 64 bit non-FP/SIMD i.e.
// 0101_000 (i.e. requires insn[31:24] == 01011000)
//
// 3) ... xx100x Data Processing Immediate
// 3a) xx___00 PC-rel. addressing (n.b. requires insn[24] == 0)
// 3b) xx___101 Move wide (immediate) (n.b. requires insn[24:23] == 01)
// strictly should be 64 bit movz #imm16<<0
// 110___10100 (i.e. requires insn[31:21] == 11010010100)
//
class RelocActions {
protected:
typedef int (*reloc_insn)(address insn_addr, address &target);
virtual reloc_insn adrpMem() = 0;
virtual reloc_insn adrpAdd() = 0;
virtual reloc_insn adrpMovk() = 0;
const address _insn_addr;
const uint32_t _insn;
static uint32_t insn_at(address insn_addr, int n) {
return ((uint32_t*)insn_addr)[n];
}
uint32_t insn_at(int n) const {
return insn_at(_insn_addr, n);
}
public:
RelocActions(address insn_addr) : _insn_addr(insn_addr), _insn(insn_at(insn_addr, 0)) {}
RelocActions(address insn_addr, uint32_t insn)
: _insn_addr(insn_addr), _insn(insn) {}
virtual int unconditionalBranch(address insn_addr, address &target) = 0;
virtual int conditionalBranch(address insn_addr, address &target) = 0;
virtual int testAndBranch(address insn_addr, address &target) = 0;
virtual int loadStore(address insn_addr, address &target) = 0;
virtual int adr(address insn_addr, address &target) = 0;
virtual int adrp(address insn_addr, address &target, reloc_insn inner) = 0;
virtual int immediate(address insn_addr, address &target) = 0;
virtual void verify(address insn_addr, address &target) = 0;
int ALWAYSINLINE run(address insn_addr, address &target) {
int instructions = 1;
uint32_t dispatch = Instruction_aarch64::extract(_insn, 30, 25);
switch(dispatch) {
case 0b001010:
case 0b001011: {
instructions = unconditionalBranch(insn_addr, target);
break;
}
case 0b101010: // Conditional branch (immediate)
case 0b011010: { // Compare & branch (immediate)
instructions = conditionalBranch(insn_addr, target);
break;
}
case 0b011011: {
instructions = testAndBranch(insn_addr, target);
break;
}
case 0b001100:
case 0b001110:
case 0b011100:
case 0b011110:
case 0b101100:
case 0b101110:
case 0b111100:
case 0b111110: {
// load/store
if ((Instruction_aarch64::extract(_insn, 29, 24) & 0b111011) == 0b011000) {
// Load register (literal)
instructions = loadStore(insn_addr, target);
break;
} else {
// nothing to do
assert(target == nullptr, "did not expect to relocate target for polling page load");
}
break;
}
case 0b001000:
case 0b011000:
case 0b101000:
case 0b111000: {
// adr/adrp
assert(Instruction_aarch64::extract(_insn, 28, 24) == 0b10000, "must be");
int shift = Instruction_aarch64::extract(_insn, 31, 31);
if (shift) {
uint32_t insn2 = insn_at(1);
if (Instruction_aarch64::extract(insn2, 29, 24) == 0b111001 &&
Instruction_aarch64::extract(_insn, 4, 0) ==
Instruction_aarch64::extract(insn2, 9, 5)) {
instructions = adrp(insn_addr, target, adrpMem());
} else if (Instruction_aarch64::extract(insn2, 31, 22) == 0b1001000100 &&
Instruction_aarch64::extract(_insn, 4, 0) ==
Instruction_aarch64::extract(insn2, 4, 0)) {
instructions = adrp(insn_addr, target, adrpAdd());
} else if (Instruction_aarch64::extract(insn2, 31, 21) == 0b11110010110 &&
Instruction_aarch64::extract(_insn, 4, 0) ==
Instruction_aarch64::extract(insn2, 4, 0)) {
instructions = adrp(insn_addr, target, adrpMovk());
} else {
ShouldNotReachHere();
}
} else {
instructions = adr(insn_addr, target);
}
break;
}
case 0b001001:
case 0b011001:
case 0b101001:
case 0b111001: {
instructions = immediate(insn_addr, target);
break;
}
default: {
ShouldNotReachHere();
}
}
verify(insn_addr, target);
return instructions * NativeInstruction::instruction_size;
}
};
class Patcher : public RelocActions {
virtual reloc_insn adrpMem() { return &Patcher::adrpMem_impl; }
virtual reloc_insn adrpAdd() { return &Patcher::adrpAdd_impl; }
virtual reloc_insn adrpMovk() { return &Patcher::adrpMovk_impl; }
public:
Patcher(address insn_addr) : RelocActions(insn_addr) {}
virtual int unconditionalBranch(address insn_addr, address &target) {
intptr_t offset = (target - insn_addr) >> 2;
Instruction_aarch64::spatch(insn_addr, 25, 0, offset);
return 1;
}
virtual int conditionalBranch(address insn_addr, address &target) {
intptr_t offset = (target - insn_addr) >> 2;
Instruction_aarch64::spatch(insn_addr, 23, 5, offset);
return 1;
}
virtual int testAndBranch(address insn_addr, address &target) {
intptr_t offset = (target - insn_addr) >> 2;
Instruction_aarch64::spatch(insn_addr, 18, 5, offset);
return 1;
}
virtual int loadStore(address insn_addr, address &target) {
intptr_t offset = (target - insn_addr) >> 2;
Instruction_aarch64::spatch(insn_addr, 23, 5, offset);
return 1;
}
virtual int adr(address insn_addr, address &target) {
#ifdef ASSERT
assert(Instruction_aarch64::extract(_insn, 28, 24) == 0b10000, "must be");
#endif
// PC-rel. addressing
ptrdiff_t offset = target - insn_addr;
int offset_lo = offset & 3;
offset >>= 2;
Instruction_aarch64::spatch(insn_addr, 23, 5, offset);
Instruction_aarch64::patch(insn_addr, 30, 29, offset_lo);
return 1;
}
virtual int adrp(address insn_addr, address &target, reloc_insn inner) {
int instructions = 1;
#ifdef ASSERT
assert(Instruction_aarch64::extract(_insn, 28, 24) == 0b10000, "must be");
#endif
ptrdiff_t offset = target - insn_addr;
instructions = 2;
precond(inner != nullptr);
// Give the inner reloc a chance to modify the target.
address adjusted_target = target;
instructions = (*inner)(insn_addr, adjusted_target);
uintptr_t pc_page = (uintptr_t)insn_addr >> 12;
uintptr_t adr_page = (uintptr_t)adjusted_target >> 12;
offset = adr_page - pc_page;
int offset_lo = offset & 3;
offset >>= 2;
Instruction_aarch64::spatch(insn_addr, 23, 5, offset);
Instruction_aarch64::patch(insn_addr, 30, 29, offset_lo);
return instructions;
}
static int adrpMem_impl(address insn_addr, address &target) {
uintptr_t dest = (uintptr_t)target;
int offset_lo = dest & 0xfff;
uint32_t insn2 = insn_at(insn_addr, 1);
uint32_t size = Instruction_aarch64::extract(insn2, 31, 30);
Instruction_aarch64::patch(insn_addr + sizeof (uint32_t), 21, 10, offset_lo >> size);
guarantee(((dest >> size) << size) == dest, "misaligned target");
return 2;
}
static int adrpAdd_impl(address insn_addr, address &target) {
uintptr_t dest = (uintptr_t)target;
int offset_lo = dest & 0xfff;
Instruction_aarch64::patch(insn_addr + sizeof (uint32_t), 21, 10, offset_lo);
return 2;
}
static int adrpMovk_impl(address insn_addr, address &target) {
uintptr_t dest = uintptr_t(target);
Instruction_aarch64::patch(insn_addr + sizeof (uint32_t), 20, 5, (uintptr_t)target >> 32);
dest = (dest & 0xffffffffULL) | (uintptr_t(insn_addr) & 0xffff00000000ULL);
target = address(dest);
return 2;
}
virtual int immediate(address insn_addr, address &target) {
assert(Instruction_aarch64::extract(_insn, 31, 21) == 0b11010010100, "must be");
uint64_t dest = (uint64_t)target;
// Move wide constant
assert(nativeInstruction_at(insn_addr+4)->is_movk(), "wrong insns in patch");
assert(nativeInstruction_at(insn_addr+8)->is_movk(), "wrong insns in patch");
Instruction_aarch64::patch(insn_addr, 20, 5, dest & 0xffff);
Instruction_aarch64::patch(insn_addr+4, 20, 5, (dest >>= 16) & 0xffff);
Instruction_aarch64::patch(insn_addr+8, 20, 5, (dest >>= 16) & 0xffff);
return 3;
}
virtual void verify(address insn_addr, address &target) {
#ifdef ASSERT
address address_is = MacroAssembler::target_addr_for_insn(insn_addr);
if (!(address_is == target)) {
tty->print_cr("%p at %p should be %p", address_is, insn_addr, target);
disnm((intptr_t)insn_addr);
assert(address_is == target, "should be");
}
#endif
}
};
// If insn1 and insn2 use the same register to form an address, either
// by an offsetted LDR or a simple ADD, return the offset. If the
// second instruction is an LDR, the offset may be scaled.
static bool offset_for(uint32_t insn1, uint32_t insn2, ptrdiff_t &byte_offset) {
if (Instruction_aarch64::extract(insn2, 29, 24) == 0b111001 &&
Instruction_aarch64::extract(insn1, 4, 0) ==
Instruction_aarch64::extract(insn2, 9, 5)) {
// Load/store register (unsigned immediate)
byte_offset = Instruction_aarch64::extract(insn2, 21, 10);
uint32_t size = Instruction_aarch64::extract(insn2, 31, 30);
byte_offset <<= size;
return true;
} else if (Instruction_aarch64::extract(insn2, 31, 22) == 0b1001000100 &&
Instruction_aarch64::extract(insn1, 4, 0) ==
Instruction_aarch64::extract(insn2, 4, 0)) {
// add (immediate)
byte_offset = Instruction_aarch64::extract(insn2, 21, 10);
return true;
}
return false;
}
class AArch64Decoder : public RelocActions {
virtual reloc_insn adrpMem() { return &AArch64Decoder::adrpMem_impl; }
virtual reloc_insn adrpAdd() { return &AArch64Decoder::adrpAdd_impl; }
virtual reloc_insn adrpMovk() { return &AArch64Decoder::adrpMovk_impl; }
public:
AArch64Decoder(address insn_addr, uint32_t insn) : RelocActions(insn_addr, insn) {}
virtual int loadStore(address insn_addr, address &target) {
intptr_t offset = Instruction_aarch64::sextract(_insn, 23, 5);
target = insn_addr + (offset << 2);
return 1;
}
virtual int unconditionalBranch(address insn_addr, address &target) {
intptr_t offset = Instruction_aarch64::sextract(_insn, 25, 0);
target = insn_addr + (offset << 2);
return 1;
}
virtual int conditionalBranch(address insn_addr, address &target) {
intptr_t offset = Instruction_aarch64::sextract(_insn, 23, 5);
target = address(((uint64_t)insn_addr + (offset << 2)));
return 1;
}
virtual int testAndBranch(address insn_addr, address &target) {
intptr_t offset = Instruction_aarch64::sextract(_insn, 18, 5);
target = address(((uint64_t)insn_addr + (offset << 2)));
return 1;
}
virtual int adr(address insn_addr, address &target) {
// PC-rel. addressing
intptr_t offset = Instruction_aarch64::extract(_insn, 30, 29);
offset |= Instruction_aarch64::sextract(_insn, 23, 5) << 2;
target = address((uint64_t)insn_addr + offset);
return 1;
}
virtual int adrp(address insn_addr, address &target, reloc_insn inner) {
assert(Instruction_aarch64::extract(_insn, 28, 24) == 0b10000, "must be");
intptr_t offset = Instruction_aarch64::extract(_insn, 30, 29);
offset |= Instruction_aarch64::sextract(_insn, 23, 5) << 2;
int shift = 12;
offset <<= shift;
uint64_t target_page = ((uint64_t)insn_addr) + offset;
target_page &= ((uint64_t)-1) << shift;
uint32_t insn2 = insn_at(1);
target = address(target_page);
precond(inner != nullptr);
(*inner)(insn_addr, target);
return 2;
}
static int adrpMem_impl(address insn_addr, address &target) {
uint32_t insn2 = insn_at(insn_addr, 1);
// Load/store register (unsigned immediate)
ptrdiff_t byte_offset = Instruction_aarch64::extract(insn2, 21, 10);
uint32_t size = Instruction_aarch64::extract(insn2, 31, 30);
byte_offset <<= size;
target += byte_offset;
return 2;
}
static int adrpAdd_impl(address insn_addr, address &target) {
uint32_t insn2 = insn_at(insn_addr, 1);
// add (immediate)
ptrdiff_t byte_offset = Instruction_aarch64::extract(insn2, 21, 10);
target += byte_offset;
return 2;
}
static int adrpMovk_impl(address insn_addr, address &target) {
uint32_t insn2 = insn_at(insn_addr, 1);
uint64_t dest = uint64_t(target);
dest = (dest & 0xffff0000ffffffff) |
((uint64_t)Instruction_aarch64::extract(insn2, 20, 5) << 32);
target = address(dest);
// We know the destination 4k page. Maybe we have a third
// instruction.
uint32_t insn = insn_at(insn_addr, 0);
uint32_t insn3 = insn_at(insn_addr, 2);
ptrdiff_t byte_offset;
if (offset_for(insn, insn3, byte_offset)) {
target += byte_offset;
return 3;
} else {
return 2;
}
}
virtual int immediate(address insn_addr, address &target) {
uint32_t *insns = (uint32_t *)insn_addr;
assert(Instruction_aarch64::extract(_insn, 31, 21) == 0b11010010100, "must be");
// Move wide constant: movz, movk, movk. See movptr().
assert(nativeInstruction_at(insns+1)->is_movk(), "wrong insns in patch");
assert(nativeInstruction_at(insns+2)->is_movk(), "wrong insns in patch");
target = address(uint64_t(Instruction_aarch64::extract(_insn, 20, 5))
+ (uint64_t(Instruction_aarch64::extract(insns[1], 20, 5)) << 16)
+ (uint64_t(Instruction_aarch64::extract(insns[2], 20, 5)) << 32));
assert(nativeInstruction_at(insn_addr+4)->is_movk(), "wrong insns in patch");
assert(nativeInstruction_at(insn_addr+8)->is_movk(), "wrong insns in patch");
return 3;
}
virtual void verify(address insn_addr, address &target) {
}
};
address MacroAssembler::target_addr_for_insn(address insn_addr, uint32_t insn) {
AArch64Decoder decoder(insn_addr, insn);
address target;
decoder.run(insn_addr, target);
return target;
}
// Patch any kind of instruction; there may be several instructions.
// Return the total length (in bytes) of the instructions.
int MacroAssembler::pd_patch_instruction_size(address insn_addr, address target) {
Patcher patcher(insn_addr);
return patcher.run(insn_addr, target);
}
int MacroAssembler::patch_oop(address insn_addr, address o) {
int instructions;
unsigned insn = *(unsigned*)insn_addr;
assert(nativeInstruction_at(insn_addr+4)->is_movk(), "wrong insns in patch");
// OOPs are either narrow (32 bits) or wide (48 bits). We encode
// narrow OOPs by setting the upper 16 bits in the first
// instruction.
if (Instruction_aarch64::extract(insn, 31, 21) == 0b11010010101) {
// Move narrow OOP
uint32_t n = CompressedOops::narrow_oop_value(cast_to_oop(o));
Instruction_aarch64::patch(insn_addr, 20, 5, n >> 16);
Instruction_aarch64::patch(insn_addr+4, 20, 5, n & 0xffff);
instructions = 2;
} else {
// Move wide OOP
assert(nativeInstruction_at(insn_addr+8)->is_movk(), "wrong insns in patch");
uintptr_t dest = (uintptr_t)o;
Instruction_aarch64::patch(insn_addr, 20, 5, dest & 0xffff);
Instruction_aarch64::patch(insn_addr+4, 20, 5, (dest >>= 16) & 0xffff);
Instruction_aarch64::patch(insn_addr+8, 20, 5, (dest >>= 16) & 0xffff);
instructions = 3;
}
return instructions * NativeInstruction::instruction_size;
}
int MacroAssembler::patch_narrow_klass(address insn_addr, narrowKlass n) {
// Metadata pointers are either narrow (32 bits) or wide (48 bits).
// We encode narrow ones by setting the upper 16 bits in the first
// instruction.
NativeInstruction *insn = nativeInstruction_at(insn_addr);
assert(Instruction_aarch64::extract(insn->encoding(), 31, 21) == 0b11010010101 &&
nativeInstruction_at(insn_addr+4)->is_movk(), "wrong insns in patch");
Instruction_aarch64::patch(insn_addr, 20, 5, n >> 16);
Instruction_aarch64::patch(insn_addr+4, 20, 5, n & 0xffff);
return 2 * NativeInstruction::instruction_size;
}
address MacroAssembler::target_addr_for_insn_or_null(address insn_addr, unsigned insn) {
if (NativeInstruction::is_ldrw_to_zr(address(&insn))) {
return nullptr;
}
return MacroAssembler::target_addr_for_insn(insn_addr, insn);
}
void MacroAssembler::safepoint_poll(Label& slow_path, bool at_return, bool acquire, bool in_nmethod, Register tmp) {
if (acquire) {
lea(tmp, Address(rthread, JavaThread::polling_word_offset()));
ldar(tmp, tmp);
} else {
ldr(tmp, Address(rthread, JavaThread::polling_word_offset()));
}
if (at_return) {
// Note that when in_nmethod is set, the stack pointer is incremented before the poll. Therefore,
// we may safely use the sp instead to perform the stack watermark check.
cmp(in_nmethod ? sp : rfp, tmp);
br(Assembler::HI, slow_path);
} else {
tbnz(tmp, log2i_exact(SafepointMechanism::poll_bit()), slow_path);
}
}
void MacroAssembler::rt_call(address dest, Register tmp) {
CodeBlob *cb = CodeCache::find_blob(dest);
if (cb) {
far_call(RuntimeAddress(dest));
} else {
lea(tmp, RuntimeAddress(dest));
blr(tmp);
}
}
void MacroAssembler::push_cont_fastpath(Register java_thread) {
if (!Continuations::enabled()) return;
Label done;
ldr(rscratch1, Address(java_thread, JavaThread::cont_fastpath_offset()));
cmp(sp, rscratch1);
br(Assembler::LS, done);
mov(rscratch1, sp); // we can't use sp as the source in str
str(rscratch1, Address(java_thread, JavaThread::cont_fastpath_offset()));
bind(done);
}
void MacroAssembler::pop_cont_fastpath(Register java_thread) {
if (!Continuations::enabled()) return;
Label done;
ldr(rscratch1, Address(java_thread, JavaThread::cont_fastpath_offset()));
cmp(sp, rscratch1);
br(Assembler::LO, done);
str(zr, Address(java_thread, JavaThread::cont_fastpath_offset()));
bind(done);
}
void MacroAssembler::reset_last_Java_frame(bool clear_fp) {
// we must set sp to zero to clear frame
str(zr, Address(rthread, JavaThread::last_Java_sp_offset()));
// must clear fp, so that compiled frames are not confused; it is
// possible that we need it only for debugging
if (clear_fp) {
str(zr, Address(rthread, JavaThread::last_Java_fp_offset()));
}
// Always clear the pc because it could have been set by make_walkable()
str(zr, Address(rthread, JavaThread::last_Java_pc_offset()));
}
// Calls to C land
//
// When entering C land, the rfp, & resp of the last Java frame have to be recorded
// in the (thread-local) JavaThread object. When leaving C land, the last Java fp
// has to be reset to 0. This is required to allow proper stack traversal.
void MacroAssembler::set_last_Java_frame(Register last_java_sp,
Register last_java_fp,
Register last_java_pc,
Register scratch) {
if (last_java_pc->is_valid()) {
str(last_java_pc, Address(rthread,
JavaThread::frame_anchor_offset()
+ JavaFrameAnchor::last_Java_pc_offset()));
}
// determine last_java_sp register
if (last_java_sp == sp) {
mov(scratch, sp);
last_java_sp = scratch;
} else if (!last_java_sp->is_valid()) {
last_java_sp = esp;
}
// last_java_fp is optional
if (last_java_fp->is_valid()) {
str(last_java_fp, Address(rthread, JavaThread::last_Java_fp_offset()));
}
// We must set sp last.
str(last_java_sp, Address(rthread, JavaThread::last_Java_sp_offset()));
}
void MacroAssembler::set_last_Java_frame(Register last_java_sp,
Register last_java_fp,
address last_java_pc,
Register scratch) {
assert(last_java_pc != nullptr, "must provide a valid PC");
adr(scratch, last_java_pc);
str(scratch, Address(rthread,
JavaThread::frame_anchor_offset()
+ JavaFrameAnchor::last_Java_pc_offset()));
set_last_Java_frame(last_java_sp, last_java_fp, noreg, scratch);
}
void MacroAssembler::set_last_Java_frame(Register last_java_sp,
Register last_java_fp,
Label &L,
Register scratch) {
if (L.is_bound()) {
set_last_Java_frame(last_java_sp, last_java_fp, target(L), scratch);
} else {
InstructionMark im(this);
L.add_patch_at(code(), locator());
set_last_Java_frame(last_java_sp, last_java_fp, pc() /* Patched later */, scratch);
}
}
static inline bool target_needs_far_branch(address addr) {
if (AOTCodeCache::is_on_for_dump()) {
return true;
}
// codecache size <= 128M
if (!MacroAssembler::far_branches()) {
return false;
}
// codecache size > 240M
if (MacroAssembler::codestub_branch_needs_far_jump()) {
return true;
}
// codecache size: 128M..240M
return !CodeCache::is_non_nmethod(addr);
}
void MacroAssembler::far_call(Address entry, Register tmp) {
assert(ReservedCodeCacheSize < 4*G, "branch out of range");
assert(CodeCache::find_blob(entry.target()) != nullptr,
"destination of far call not found in code cache");
assert(entry.rspec().type() == relocInfo::external_word_type
|| entry.rspec().type() == relocInfo::runtime_call_type
|| entry.rspec().type() == relocInfo::none, "wrong entry relocInfo type");
if (target_needs_far_branch(entry.target())) {
uint64_t offset;
// We can use ADRP here because we know that the total size of
// the code cache cannot exceed 2Gb (ADRP limit is 4GB).
adrp(tmp, entry, offset);
add(tmp, tmp, offset);
blr(tmp);
} else {
bl(entry);
}
}
int MacroAssembler::far_jump(Address entry, Register tmp) {
assert(ReservedCodeCacheSize < 4*G, "branch out of range");
assert(CodeCache::find_blob(entry.target()) != nullptr,
"destination of far call not found in code cache");
assert(entry.rspec().type() == relocInfo::external_word_type
|| entry.rspec().type() == relocInfo::runtime_call_type
|| entry.rspec().type() == relocInfo::none, "wrong entry relocInfo type");
address start = pc();
if (target_needs_far_branch(entry.target())) {
uint64_t offset;
// We can use ADRP here because we know that the total size of
// the code cache cannot exceed 2Gb (ADRP limit is 4GB).
adrp(tmp, entry, offset);
add(tmp, tmp, offset);
br(tmp);
} else {
b(entry);
}
return pc() - start;
}
void MacroAssembler::reserved_stack_check() {
// testing if reserved zone needs to be enabled
Label no_reserved_zone_enabling;
ldr(rscratch1, Address(rthread, JavaThread::reserved_stack_activation_offset()));
cmp(sp, rscratch1);
br(Assembler::LO, no_reserved_zone_enabling);
enter(); // LR and FP are live.
lea(rscratch1, RuntimeAddress(CAST_FROM_FN_PTR(address, SharedRuntime::enable_stack_reserved_zone)));
mov(c_rarg0, rthread);
blr(rscratch1);
leave();
// We have already removed our own frame.
// throw_delayed_StackOverflowError will think that it's been
// called by our caller.
lea(rscratch1, RuntimeAddress(SharedRuntime::throw_delayed_StackOverflowError_entry()));
br(rscratch1);
should_not_reach_here();
bind(no_reserved_zone_enabling);
}
static void pass_arg0(MacroAssembler* masm, Register arg) {
if (c_rarg0 != arg ) {
masm->mov(c_rarg0, arg);
}
}
static void pass_arg1(MacroAssembler* masm, Register arg) {
if (c_rarg1 != arg ) {
masm->mov(c_rarg1, arg);
}
}
static void pass_arg2(MacroAssembler* masm, Register arg) {
if (c_rarg2 != arg ) {
masm->mov(c_rarg2, arg);
}
}
static void pass_arg3(MacroAssembler* masm, Register arg) {
if (c_rarg3 != arg ) {
masm->mov(c_rarg3, arg);
}
}
static bool is_preemptable(address entry_point) {
return entry_point == CAST_FROM_FN_PTR(address, InterpreterRuntime::monitorenter);
}
void MacroAssembler::call_VM_base(Register oop_result,
Register java_thread,
Register last_java_sp,
address entry_point,
int number_of_arguments,
bool check_exceptions) {
// determine java_thread register
if (!java_thread->is_valid()) {
java_thread = rthread;
}
// determine last_java_sp register
if (!last_java_sp->is_valid()) {
last_java_sp = esp;
}
// debugging support
assert(number_of_arguments >= 0 , "cannot have negative number of arguments");
assert(java_thread == rthread, "unexpected register");
#ifdef ASSERT
// TraceBytecodes does not use r12 but saves it over the call, so don't verify
// if ((UseCompressedOops || UseCompressedClassPointers) && !TraceBytecodes) verify_heapbase("call_VM_base: heap base corrupted?");
#endif // ASSERT
assert(java_thread != oop_result , "cannot use the same register for java_thread & oop_result");
assert(java_thread != last_java_sp, "cannot use the same register for java_thread & last_java_sp");
// push java thread (becomes first argument of C function)
mov(c_rarg0, java_thread);
// set last Java frame before call
assert(last_java_sp != rfp, "can't use rfp");
Label l;
if (is_preemptable(entry_point)) {
// skip setting last_pc since we already set it to desired value.
set_last_Java_frame(last_java_sp, rfp, noreg, rscratch1);
} else {
set_last_Java_frame(last_java_sp, rfp, l, rscratch1);
}
// do the call, remove parameters
MacroAssembler::call_VM_leaf_base(entry_point, number_of_arguments, &l);
// lr could be poisoned with PAC signature during throw_pending_exception
// if it was tail-call optimized by compiler, since lr is not callee-saved
// reload it with proper value
adr(lr, l);
// reset last Java frame
// Only interpreter should have to clear fp
reset_last_Java_frame(true);
// C++ interp handles this in the interpreter
check_and_handle_popframe(java_thread);
check_and_handle_earlyret(java_thread);
if (check_exceptions) {
// check for pending exceptions (java_thread is set upon return)
ldr(rscratch1, Address(java_thread, in_bytes(Thread::pending_exception_offset())));
Label ok;
cbz(rscratch1, ok);
lea(rscratch1, RuntimeAddress(StubRoutines::forward_exception_entry()));
br(rscratch1);
bind(ok);
}
// get oop result if there is one and reset the value in the thread
if (oop_result->is_valid()) {
get_vm_result_oop(oop_result, java_thread);
}
}
void MacroAssembler::call_VM_helper(Register oop_result, address entry_point, int number_of_arguments, bool check_exceptions) {
call_VM_base(oop_result, noreg, noreg, entry_point, number_of_arguments, check_exceptions);
}
// Check the entry target is always reachable from any branch.
static bool is_always_within_branch_range(Address entry) {
if (AOTCodeCache::is_on_for_dump()) {
return false;
}
const address target = entry.target();
if (!CodeCache::contains(target)) {
// We always use trampolines for callees outside CodeCache.
assert(entry.rspec().type() == relocInfo::runtime_call_type, "non-runtime call of an external target");
return false;
}
if (!MacroAssembler::far_branches()) {
return true;
}
if (entry.rspec().type() == relocInfo::runtime_call_type) {
// Runtime calls are calls of a non-compiled method (stubs, adapters).
// Non-compiled methods stay forever in CodeCache.
// We check whether the longest possible branch is within the branch range.
assert(CodeCache::find_blob(target) != nullptr &&
!CodeCache::find_blob(target)->is_nmethod(),
"runtime call of compiled method");
const address right_longest_branch_start = CodeCache::high_bound() - NativeInstruction::instruction_size;
const address left_longest_branch_start = CodeCache::low_bound();
const bool is_reachable = Assembler::reachable_from_branch_at(left_longest_branch_start, target) &&
Assembler::reachable_from_branch_at(right_longest_branch_start, target);
return is_reachable;
}
return false;
}
// Maybe emit a call via a trampoline. If the code cache is small
// trampolines won't be emitted.
address MacroAssembler::trampoline_call(Address entry) {
assert(entry.rspec().type() == relocInfo::runtime_call_type
|| entry.rspec().type() == relocInfo::opt_virtual_call_type
|| entry.rspec().type() == relocInfo::static_call_type
|| entry.rspec().type() == relocInfo::virtual_call_type, "wrong reloc type");
address target = entry.target();
if (!is_always_within_branch_range(entry)) {
if (!in_scratch_emit_size()) {
// We don't want to emit a trampoline if C2 is generating dummy
// code during its branch shortening phase.
if (entry.rspec().type() == relocInfo::runtime_call_type) {
assert(CodeBuffer::supports_shared_stubs(), "must support shared stubs");
code()->share_trampoline_for(entry.target(), offset());
} else {
address stub = emit_trampoline_stub(offset(), target);
if (stub == nullptr) {
postcond(pc() == badAddress);
return nullptr; // CodeCache is full
}
}
}
target = pc();
}
address call_pc = pc();
relocate(entry.rspec());
bl(target);
postcond(pc() != badAddress);
return call_pc;
}
// Emit a trampoline stub for a call to a target which is too far away.
//
// code sequences:
//
// call-site:
// branch-and-link to <destination> or <trampoline stub>
//
// Related trampoline stub for this call site in the stub section:
// load the call target from the constant pool
// branch (LR still points to the call site above)
address MacroAssembler::emit_trampoline_stub(int insts_call_instruction_offset,
address dest) {
// Max stub size: alignment nop, TrampolineStub.
address stub = start_a_stub(max_trampoline_stub_size());
if (stub == nullptr) {
return nullptr; // CodeBuffer::expand failed
}
// Create a trampoline stub relocation which relates this trampoline stub
// with the call instruction at insts_call_instruction_offset in the
// instructions code-section.
align(wordSize);
relocate(trampoline_stub_Relocation::spec(code()->insts()->start()
+ insts_call_instruction_offset));
const int stub_start_offset = offset();
// Now, create the trampoline stub's code:
// - load the call
// - call
Label target;
ldr(rscratch1, target);
br(rscratch1);
bind(target);
assert(offset() - stub_start_offset == NativeCallTrampolineStub::data_offset,
"should be");
emit_int64((int64_t)dest);
const address stub_start_addr = addr_at(stub_start_offset);
assert(is_NativeCallTrampolineStub_at(stub_start_addr), "doesn't look like a trampoline");
end_a_stub();
return stub_start_addr;
}
int MacroAssembler::max_trampoline_stub_size() {
// Max stub size: alignment nop, TrampolineStub.
return NativeInstruction::instruction_size + NativeCallTrampolineStub::instruction_size;
}
void MacroAssembler::emit_static_call_stub() {
// CompiledDirectCall::set_to_interpreted knows the
// exact layout of this stub.
isb();
mov_metadata(rmethod, nullptr);
// Jump to the entry point of the c2i stub.
movptr(rscratch1, 0);
br(rscratch1);
}
int MacroAssembler::static_call_stub_size() {
// isb; movk; movz; movz; movk; movz; movz; br
return 8 * NativeInstruction::instruction_size;
}
void MacroAssembler::c2bool(Register x) {
// implements x == 0 ? 0 : 1
// note: must only look at least-significant byte of x
// since C-style booleans are stored in one byte
// only! (was bug)
tst(x, 0xff);
cset(x, Assembler::NE);
}
address MacroAssembler::ic_call(address entry, jint method_index) {
RelocationHolder rh = virtual_call_Relocation::spec(pc(), method_index);
movptr(rscratch2, (intptr_t)Universe::non_oop_word());
return trampoline_call(Address(entry, rh));
}
int MacroAssembler::ic_check_size() {
int extra_instructions = UseCompactObjectHeaders ? 1 : 0;
if (target_needs_far_branch(CAST_FROM_FN_PTR(address, SharedRuntime::get_ic_miss_stub()))) {
return NativeInstruction::instruction_size * (7 + extra_instructions);
} else {
return NativeInstruction::instruction_size * (5 + extra_instructions);
}
}
int MacroAssembler::ic_check(int end_alignment) {
Register receiver = j_rarg0;
Register data = rscratch2;
Register tmp1 = rscratch1;
Register tmp2 = r10;
// The UEP of a code blob ensures that the VEP is padded. However, the padding of the UEP is placed
// before the inline cache check, so we don't have to execute any nop instructions when dispatching
// through the UEP, yet we can ensure that the VEP is aligned appropriately. That's why we align
// before the inline cache check here, and not after
align(end_alignment, offset() + ic_check_size());
int uep_offset = offset();
if (UseCompactObjectHeaders) {
load_narrow_klass_compact(tmp1, receiver);
ldrw(tmp2, Address(data, CompiledICData::speculated_klass_offset()));
cmpw(tmp1, tmp2);
} else if (UseCompressedClassPointers) {
ldrw(tmp1, Address(receiver, oopDesc::klass_offset_in_bytes()));
ldrw(tmp2, Address(data, CompiledICData::speculated_klass_offset()));
cmpw(tmp1, tmp2);
} else {
ldr(tmp1, Address(receiver, oopDesc::klass_offset_in_bytes()));
ldr(tmp2, Address(data, CompiledICData::speculated_klass_offset()));
cmp(tmp1, tmp2);
}
Label dont;
br(Assembler::EQ, dont);
far_jump(RuntimeAddress(SharedRuntime::get_ic_miss_stub()));
bind(dont);
assert((offset() % end_alignment) == 0, "Misaligned verified entry point");
return uep_offset;
}
// Implementation of call_VM versions
void MacroAssembler::call_VM(Register oop_result,
address entry_point,
bool check_exceptions) {
call_VM_helper(oop_result, entry_point, 0, check_exceptions);
}
void MacroAssembler::call_VM(Register oop_result,
address entry_point,
Register arg_1,
bool check_exceptions) {
pass_arg1(this, arg_1);
call_VM_helper(oop_result, entry_point, 1, check_exceptions);
}
void MacroAssembler::call_VM(Register oop_result,
address entry_point,
Register arg_1,
Register arg_2,
bool check_exceptions) {
assert_different_registers(arg_1, c_rarg2);
pass_arg2(this, arg_2);
pass_arg1(this, arg_1);
call_VM_helper(oop_result, entry_point, 2, check_exceptions);
}
void MacroAssembler::call_VM(Register oop_result,
address entry_point,
Register arg_1,
Register arg_2,
Register arg_3,
bool check_exceptions) {
assert_different_registers(arg_1, c_rarg2, c_rarg3);
assert_different_registers(arg_2, c_rarg3);
pass_arg3(this, arg_3);
pass_arg2(this, arg_2);
pass_arg1(this, arg_1);
call_VM_helper(oop_result, entry_point, 3, check_exceptions);
}
void MacroAssembler::call_VM(Register oop_result,
Register last_java_sp,
address entry_point,
int number_of_arguments,
bool check_exceptions) {
call_VM_base(oop_result, rthread, last_java_sp, entry_point, number_of_arguments, check_exceptions);
}
void MacroAssembler::call_VM(Register oop_result,
Register last_java_sp,
address entry_point,
Register arg_1,
bool check_exceptions) {
pass_arg1(this, arg_1);
call_VM(oop_result, last_java_sp, entry_point, 1, check_exceptions);
}
void MacroAssembler::call_VM(Register oop_result,
Register last_java_sp,
address entry_point,
Register arg_1,
Register arg_2,
bool check_exceptions) {
assert_different_registers(arg_1, c_rarg2);
pass_arg2(this, arg_2);
pass_arg1(this, arg_1);
call_VM(oop_result, last_java_sp, entry_point, 2, check_exceptions);
}
void MacroAssembler::call_VM(Register oop_result,
Register last_java_sp,
address entry_point,
Register arg_1,
Register arg_2,
Register arg_3,
bool check_exceptions) {
assert_different_registers(arg_1, c_rarg2, c_rarg3);
assert_different_registers(arg_2, c_rarg3);
pass_arg3(this, arg_3);
pass_arg2(this, arg_2);
pass_arg1(this, arg_1);
call_VM(oop_result, last_java_sp, entry_point, 3, check_exceptions);
}
void MacroAssembler::get_vm_result_oop(Register oop_result, Register java_thread) {
ldr(oop_result, Address(java_thread, JavaThread::vm_result_oop_offset()));
str(zr, Address(java_thread, JavaThread::vm_result_oop_offset()));
verify_oop_msg(oop_result, "broken oop in call_VM_base");
}
void MacroAssembler::get_vm_result_metadata(Register metadata_result, Register java_thread) {
ldr(metadata_result, Address(java_thread, JavaThread::vm_result_metadata_offset()));
str(zr, Address(java_thread, JavaThread::vm_result_metadata_offset()));
}
void MacroAssembler::align(int modulus) {
align(modulus, offset());
}
// Ensure that the code at target bytes offset from the current offset() is aligned
// according to modulus.
void MacroAssembler::align(int modulus, int target) {
int delta = target - offset();
while ((offset() + delta) % modulus != 0) nop();
}
void MacroAssembler::post_call_nop() {
if (!Continuations::enabled()) {
return;
}
InstructionMark im(this);
relocate(post_call_nop_Relocation::spec());
InlineSkippedInstructionsCounter skipCounter(this);
nop();
movk(zr, 0);
movk(zr, 0);
}
// these are no-ops overridden by InterpreterMacroAssembler
void MacroAssembler::check_and_handle_earlyret(Register java_thread) { }
void MacroAssembler::check_and_handle_popframe(Register java_thread) { }
// Look up the method for a megamorphic invokeinterface call.
// The target method is determined by <intf_klass, itable_index>.
// The receiver klass is in recv_klass.
// On success, the result will be in method_result, and execution falls through.
// On failure, execution transfers to the given label.
void MacroAssembler::lookup_interface_method(Register recv_klass,
Register intf_klass,
RegisterOrConstant itable_index,
Register method_result,
Register scan_temp,
Label& L_no_such_interface,
bool return_method) {
assert_different_registers(recv_klass, intf_klass, scan_temp);
assert_different_registers(method_result, intf_klass, scan_temp);
assert(recv_klass != method_result || !return_method,
"recv_klass can be destroyed when method isn't needed");
assert(itable_index.is_constant() || itable_index.as_register() == method_result,
"caller must use same register for non-constant itable index as for method");
// Compute start of first itableOffsetEntry (which is at the end of the vtable)
int vtable_base = in_bytes(Klass::vtable_start_offset());
int itentry_off = in_bytes(itableMethodEntry::method_offset());
int scan_step = itableOffsetEntry::size() * wordSize;
int vte_size = vtableEntry::size_in_bytes();
assert(vte_size == wordSize, "else adjust times_vte_scale");
ldrw(scan_temp, Address(recv_klass, Klass::vtable_length_offset()));
// Could store the aligned, prescaled offset in the klass.
// lea(scan_temp, Address(recv_klass, scan_temp, times_vte_scale, vtable_base));
lea(scan_temp, Address(recv_klass, scan_temp, Address::lsl(3)));
add(scan_temp, scan_temp, vtable_base);
if (return_method) {
// Adjust recv_klass by scaled itable_index, so we can free itable_index.
assert(itableMethodEntry::size() * wordSize == wordSize, "adjust the scaling in the code below");
// lea(recv_klass, Address(recv_klass, itable_index, Address::times_ptr, itentry_off));
lea(recv_klass, Address(recv_klass, itable_index, Address::lsl(3)));
if (itentry_off)
add(recv_klass, recv_klass, itentry_off);
}
// for (scan = klass->itable(); scan->interface() != nullptr; scan += scan_step) {
// if (scan->interface() == intf) {
// result = (klass + scan->offset() + itable_index);
// }
// }
Label search, found_method;
ldr(method_result, Address(scan_temp, itableOffsetEntry::interface_offset()));
cmp(intf_klass, method_result);
br(Assembler::EQ, found_method);
bind(search);
// Check that the previous entry is non-null. A null entry means that
// the receiver class doesn't implement the interface, and wasn't the
// same as when the caller was compiled.
cbz(method_result, L_no_such_interface);
if (itableOffsetEntry::interface_offset() != 0) {
add(scan_temp, scan_temp, scan_step);
ldr(method_result, Address(scan_temp, itableOffsetEntry::interface_offset()));
} else {
ldr(method_result, Address(pre(scan_temp, scan_step)));
}
cmp(intf_klass, method_result);
br(Assembler::NE, search);
bind(found_method);
// Got a hit.
if (return_method) {
ldrw(scan_temp, Address(scan_temp, itableOffsetEntry::offset_offset()));
ldr(method_result, Address(recv_klass, scan_temp, Address::uxtw(0)));
}
}
// Look up the method for a megamorphic invokeinterface call in a single pass over itable:
// - check recv_klass (actual object class) is a subtype of resolved_klass from CompiledICData
// - find a holder_klass (class that implements the method) vtable offset and get the method from vtable by index
// The target method is determined by <holder_klass, itable_index>.
// The receiver klass is in recv_klass.
// On success, the result will be in method_result, and execution falls through.
// On failure, execution transfers to the given label.
void MacroAssembler::lookup_interface_method_stub(Register recv_klass,
Register holder_klass,
Register resolved_klass,
Register method_result,
Register temp_itbl_klass,
Register scan_temp,
int itable_index,
Label& L_no_such_interface) {
// 'method_result' is only used as output register at the very end of this method.
// Until then we can reuse it as 'holder_offset'.
Register holder_offset = method_result;
assert_different_registers(resolved_klass, recv_klass, holder_klass, temp_itbl_klass, scan_temp, holder_offset);
int vtable_start_offset = in_bytes(Klass::vtable_start_offset());
int itable_offset_entry_size = itableOffsetEntry::size() * wordSize;
int ioffset = in_bytes(itableOffsetEntry::interface_offset());
int ooffset = in_bytes(itableOffsetEntry::offset_offset());
Label L_loop_search_resolved_entry, L_resolved_found, L_holder_found;
ldrw(scan_temp, Address(recv_klass, Klass::vtable_length_offset()));
add(recv_klass, recv_klass, vtable_start_offset + ioffset);
// itableOffsetEntry[] itable = recv_klass + Klass::vtable_start_offset() + sizeof(vtableEntry) * recv_klass->_vtable_len;
// temp_itbl_klass = itable[0]._interface;
int vtblEntrySize = vtableEntry::size_in_bytes();
assert(vtblEntrySize == wordSize, "ldr lsl shift amount must be 3");
ldr(temp_itbl_klass, Address(recv_klass, scan_temp, Address::lsl(exact_log2(vtblEntrySize))));
mov(holder_offset, zr);
// scan_temp = &(itable[0]._interface)
lea(scan_temp, Address(recv_klass, scan_temp, Address::lsl(exact_log2(vtblEntrySize))));
// Initial checks:
// - if (holder_klass != resolved_klass), go to "scan for resolved"
// - if (itable[0] == holder_klass), shortcut to "holder found"
// - if (itable[0] == 0), no such interface
cmp(resolved_klass, holder_klass);
br(Assembler::NE, L_loop_search_resolved_entry);
cmp(holder_klass, temp_itbl_klass);
br(Assembler::EQ, L_holder_found);
cbz(temp_itbl_klass, L_no_such_interface);
// Loop: Look for holder_klass record in itable
// do {
// temp_itbl_klass = *(scan_temp += itable_offset_entry_size);
// if (temp_itbl_klass == holder_klass) {
// goto L_holder_found; // Found!
// }
// } while (temp_itbl_klass != 0);
// goto L_no_such_interface // Not found.
Label L_search_holder;
bind(L_search_holder);
ldr(temp_itbl_klass, Address(pre(scan_temp, itable_offset_entry_size)));
cmp(holder_klass, temp_itbl_klass);
br(Assembler::EQ, L_holder_found);
cbnz(temp_itbl_klass, L_search_holder);
b(L_no_such_interface);
// Loop: Look for resolved_class record in itable
// while (true) {
// temp_itbl_klass = *(scan_temp += itable_offset_entry_size);
// if (temp_itbl_klass == 0) {
// goto L_no_such_interface;
// }
// if (temp_itbl_klass == resolved_klass) {
// goto L_resolved_found; // Found!
// }
// if (temp_itbl_klass == holder_klass) {
// holder_offset = scan_temp;
// }
// }
//
Label L_loop_search_resolved;
bind(L_loop_search_resolved);
ldr(temp_itbl_klass, Address(pre(scan_temp, itable_offset_entry_size)));
bind(L_loop_search_resolved_entry);
cbz(temp_itbl_klass, L_no_such_interface);
cmp(resolved_klass, temp_itbl_klass);
br(Assembler::EQ, L_resolved_found);
cmp(holder_klass, temp_itbl_klass);
br(Assembler::NE, L_loop_search_resolved);
mov(holder_offset, scan_temp);
b(L_loop_search_resolved);
// See if we already have a holder klass. If not, go and scan for it.
bind(L_resolved_found);
cbz(holder_offset, L_search_holder);
mov(scan_temp, holder_offset);
// Finally, scan_temp contains holder_klass vtable offset
bind(L_holder_found);
ldrw(method_result, Address(scan_temp, ooffset - ioffset));
add(recv_klass, recv_klass, itable_index * wordSize + in_bytes(itableMethodEntry::method_offset())
- vtable_start_offset - ioffset); // substract offsets to restore the original value of recv_klass
ldr(method_result, Address(recv_klass, method_result, Address::uxtw(0)));
}
// virtual method calling
void MacroAssembler::lookup_virtual_method(Register recv_klass,
RegisterOrConstant vtable_index,
Register method_result) {
assert(vtableEntry::size() * wordSize == 8,
"adjust the scaling in the code below");
int64_t vtable_offset_in_bytes = in_bytes(Klass::vtable_start_offset() + vtableEntry::method_offset());
if (vtable_index.is_register()) {
lea(method_result, Address(recv_klass,
vtable_index.as_register(),
Address::lsl(LogBytesPerWord)));
ldr(method_result, Address(method_result, vtable_offset_in_bytes));
} else {
vtable_offset_in_bytes += vtable_index.as_constant() * wordSize;
ldr(method_result,
form_address(rscratch1, recv_klass, vtable_offset_in_bytes, 0));
}
}
void MacroAssembler::check_klass_subtype(Register sub_klass,
Register super_klass,
Register temp_reg,
Label& L_success) {
Label L_failure;
check_klass_subtype_fast_path(sub_klass, super_klass, temp_reg, &L_success, &L_failure, nullptr);
check_klass_subtype_slow_path(sub_klass, super_klass, temp_reg, noreg, &L_success, nullptr);
bind(L_failure);
}
void MacroAssembler::check_klass_subtype_fast_path(Register sub_klass,
Register super_klass,
Register temp_reg,
Label* L_success,
Label* L_failure,
Label* L_slow_path,
Register super_check_offset) {
assert_different_registers(sub_klass, super_klass, temp_reg, super_check_offset);
bool must_load_sco = ! super_check_offset->is_valid();
if (must_load_sco) {
assert(temp_reg != noreg, "supply either a temp or a register offset");
}
Label L_fallthrough;
int label_nulls = 0;
if (L_success == nullptr) { L_success = &L_fallthrough; label_nulls++; }
if (L_failure == nullptr) { L_failure = &L_fallthrough; label_nulls++; }
if (L_slow_path == nullptr) { L_slow_path = &L_fallthrough; label_nulls++; }
assert(label_nulls <= 1, "at most one null in the batch");
int sco_offset = in_bytes(Klass::super_check_offset_offset());
Address super_check_offset_addr(super_klass, sco_offset);
// Hacked jmp, which may only be used just before L_fallthrough.
#define final_jmp(label) \
if (&(label) == &L_fallthrough) { /*do nothing*/ } \
else b(label) /*omit semi*/
// If the pointers are equal, we are done (e.g., String[] elements).
// This self-check enables sharing of secondary supertype arrays among
// non-primary types such as array-of-interface. Otherwise, each such
// type would need its own customized SSA.
// We move this check to the front of the fast path because many
// type checks are in fact trivially successful in this manner,
// so we get a nicely predicted branch right at the start of the check.
cmp(sub_klass, super_klass);
br(Assembler::EQ, *L_success);
// Check the supertype display:
if (must_load_sco) {
ldrw(temp_reg, super_check_offset_addr);
super_check_offset = temp_reg;
}
Address super_check_addr(sub_klass, super_check_offset);
ldr(rscratch1, super_check_addr);
cmp(super_klass, rscratch1); // load displayed supertype
br(Assembler::EQ, *L_success);
// This check has worked decisively for primary supers.
// Secondary supers are sought in the super_cache ('super_cache_addr').
// (Secondary supers are interfaces and very deeply nested subtypes.)
// This works in the same check above because of a tricky aliasing
// between the super_cache and the primary super display elements.
// (The 'super_check_addr' can address either, as the case requires.)
// Note that the cache is updated below if it does not help us find
// what we need immediately.
// So if it was a primary super, we can just fail immediately.
// Otherwise, it's the slow path for us (no success at this point).
sub(rscratch1, super_check_offset, in_bytes(Klass::secondary_super_cache_offset()));
if (L_failure == &L_fallthrough) {
cbz(rscratch1, *L_slow_path);
} else {
cbnz(rscratch1, *L_failure);
final_jmp(*L_slow_path);
}
bind(L_fallthrough);
#undef final_jmp
}
// These two are taken from x86, but they look generally useful
// scans count pointer sized words at [addr] for occurrence of value,
// generic
void MacroAssembler::repne_scan(Register addr, Register value, Register count,
Register scratch) {
Label Lloop, Lexit;
cbz(count, Lexit);
bind(Lloop);
ldr(scratch, post(addr, wordSize));
cmp(value, scratch);
br(EQ, Lexit);
sub(count, count, 1);
cbnz(count, Lloop);
bind(Lexit);
}
// scans count 4 byte words at [addr] for occurrence of value,
// generic
void MacroAssembler::repne_scanw(Register addr, Register value, Register count,
Register scratch) {
Label Lloop, Lexit;
cbz(count, Lexit);
bind(Lloop);
ldrw(scratch, post(addr, wordSize));
cmpw(value, scratch);
br(EQ, Lexit);
sub(count, count, 1);
cbnz(count, Lloop);
bind(Lexit);
}
void MacroAssembler::check_klass_subtype_slow_path_linear(Register sub_klass,
Register super_klass,
Register temp_reg,
Register temp2_reg,
Label* L_success,
Label* L_failure,
bool set_cond_codes) {
// NB! Callers may assume that, when temp2_reg is a valid register,
// this code sets it to a nonzero value.
assert_different_registers(sub_klass, super_klass, temp_reg);
if (temp2_reg != noreg)
assert_different_registers(sub_klass, super_klass, temp_reg, temp2_reg, rscratch1);
#define IS_A_TEMP(reg) ((reg) == temp_reg || (reg) == temp2_reg)
Label L_fallthrough;
int label_nulls = 0;
if (L_success == nullptr) { L_success = &L_fallthrough; label_nulls++; }
if (L_failure == nullptr) { L_failure = &L_fallthrough; label_nulls++; }
assert(label_nulls <= 1, "at most one null in the batch");
// a couple of useful fields in sub_klass:
int ss_offset = in_bytes(Klass::secondary_supers_offset());
int sc_offset = in_bytes(Klass::secondary_super_cache_offset());
Address secondary_supers_addr(sub_klass, ss_offset);
Address super_cache_addr( sub_klass, sc_offset);
BLOCK_COMMENT("check_klass_subtype_slow_path");
// Do a linear scan of the secondary super-klass chain.
// This code is rarely used, so simplicity is a virtue here.
// The repne_scan instruction uses fixed registers, which we must spill.
// Don't worry too much about pre-existing connections with the input regs.
assert(sub_klass != r0, "killed reg"); // killed by mov(r0, super)
assert(sub_klass != r2, "killed reg"); // killed by lea(r2, &pst_counter)
RegSet pushed_registers;
if (!IS_A_TEMP(r2)) pushed_registers += r2;
if (!IS_A_TEMP(r5)) pushed_registers += r5;
if (super_klass != r0) {
if (!IS_A_TEMP(r0)) pushed_registers += r0;
}
push(pushed_registers, sp);
// Get super_klass value into r0 (even if it was in r5 or r2).
if (super_klass != r0) {
mov(r0, super_klass);
}
#ifndef PRODUCT
incrementw(ExternalAddress((address)&SharedRuntime::_partial_subtype_ctr));
#endif //PRODUCT
// We will consult the secondary-super array.
ldr(r5, secondary_supers_addr);
// Load the array length.
ldrw(r2, Address(r5, Array<Klass*>::length_offset_in_bytes()));
// Skip to start of data.
add(r5, r5, Array<Klass*>::base_offset_in_bytes());
cmp(sp, zr); // Clear Z flag; SP is never zero
// Scan R2 words at [R5] for an occurrence of R0.
// Set NZ/Z based on last compare.
repne_scan(r5, r0, r2, rscratch1);
// Unspill the temp. registers:
pop(pushed_registers, sp);
br(Assembler::NE, *L_failure);
// Success. Cache the super we found and proceed in triumph.
if (UseSecondarySupersCache) {
str(super_klass, super_cache_addr);
}
if (L_success != &L_fallthrough) {
b(*L_success);
}
#undef IS_A_TEMP
bind(L_fallthrough);
}
// If Register r is invalid, remove a new register from
// available_regs, and add new register to regs_to_push.
Register MacroAssembler::allocate_if_noreg(Register r,
RegSetIterator<Register> &available_regs,
RegSet &regs_to_push) {
if (!r->is_valid()) {
r = *available_regs++;
regs_to_push += r;
}
return r;
}
// check_klass_subtype_slow_path_table() looks for super_klass in the
// hash table belonging to super_klass, branching to L_success or
// L_failure as appropriate. This is essentially a shim which
// allocates registers as necessary then calls
// lookup_secondary_supers_table() to do the work. Any of the temp
// regs may be noreg, in which case this logic will chooses some
// registers push and pop them from the stack.
void MacroAssembler::check_klass_subtype_slow_path_table(Register sub_klass,
Register super_klass,
Register temp_reg,
Register temp2_reg,
Register temp3_reg,
Register result_reg,
FloatRegister vtemp,
Label* L_success,
Label* L_failure,
bool set_cond_codes) {
RegSet temps = RegSet::of(temp_reg, temp2_reg, temp3_reg);
assert_different_registers(sub_klass, super_klass, temp_reg, temp2_reg, rscratch1);
Label L_fallthrough;
int label_nulls = 0;
if (L_success == nullptr) { L_success = &L_fallthrough; label_nulls++; }
if (L_failure == nullptr) { L_failure = &L_fallthrough; label_nulls++; }
assert(label_nulls <= 1, "at most one null in the batch");
BLOCK_COMMENT("check_klass_subtype_slow_path");
RegSetIterator<Register> available_regs
= (RegSet::range(r0, r15) - temps - sub_klass - super_klass).begin();
RegSet pushed_regs;
temp_reg = allocate_if_noreg(temp_reg, available_regs, pushed_regs);
temp2_reg = allocate_if_noreg(temp2_reg, available_regs, pushed_regs);
temp3_reg = allocate_if_noreg(temp3_reg, available_regs, pushed_regs);
result_reg = allocate_if_noreg(result_reg, available_regs, pushed_regs);
push(pushed_regs, sp);
lookup_secondary_supers_table_var(sub_klass,
super_klass,
temp_reg, temp2_reg, temp3_reg, vtemp, result_reg,
nullptr);
cmp(result_reg, zr);
// Unspill the temp. registers:
pop(pushed_regs, sp);
// NB! Callers may assume that, when set_cond_codes is true, this
// code sets temp2_reg to a nonzero value.
if (set_cond_codes) {
mov(temp2_reg, 1);
}
br(Assembler::NE, *L_failure);
if (L_success != &L_fallthrough) {
b(*L_success);
}
bind(L_fallthrough);
}
void MacroAssembler::check_klass_subtype_slow_path(Register sub_klass,
Register super_klass,
Register temp_reg,
Register temp2_reg,
Label* L_success,
Label* L_failure,
bool set_cond_codes) {
if (UseSecondarySupersTable) {
check_klass_subtype_slow_path_table
(sub_klass, super_klass, temp_reg, temp2_reg, /*temp3*/noreg, /*result*/noreg,
/*vtemp*/fnoreg,
L_success, L_failure, set_cond_codes);
} else {
check_klass_subtype_slow_path_linear
(sub_klass, super_klass, temp_reg, temp2_reg, L_success, L_failure, set_cond_codes);
}
}
// Ensure that the inline code and the stub are using the same registers.
#define LOOKUP_SECONDARY_SUPERS_TABLE_REGISTERS \
do { \
assert(r_super_klass == r0 && \
r_array_base == r1 && \
r_array_length == r2 && \
(r_array_index == r3 || r_array_index == noreg) && \
(r_sub_klass == r4 || r_sub_klass == noreg) && \
(r_bitmap == rscratch2 || r_bitmap == noreg) && \
(result == r5 || result == noreg), "registers must match aarch64.ad"); \
} while(0)
bool MacroAssembler::lookup_secondary_supers_table_const(Register r_sub_klass,
Register r_super_klass,
Register temp1,
Register temp2,
Register temp3,
FloatRegister vtemp,
Register result,
u1 super_klass_slot,
bool stub_is_near) {
assert_different_registers(r_sub_klass, temp1, temp2, temp3, result, rscratch1, rscratch2);
Label L_fallthrough;
BLOCK_COMMENT("lookup_secondary_supers_table {");
const Register
r_array_base = temp1, // r1
r_array_length = temp2, // r2
r_array_index = temp3, // r3
r_bitmap = rscratch2;
LOOKUP_SECONDARY_SUPERS_TABLE_REGISTERS;
u1 bit = super_klass_slot;
// Make sure that result is nonzero if the TBZ below misses.
mov(result, 1);
// We're going to need the bitmap in a vector reg and in a core reg,
// so load both now.
ldr(r_bitmap, Address(r_sub_klass, Klass::secondary_supers_bitmap_offset()));
if (bit != 0) {
ldrd(vtemp, Address(r_sub_klass, Klass::secondary_supers_bitmap_offset()));
}
// First check the bitmap to see if super_klass might be present. If
// the bit is zero, we are certain that super_klass is not one of
// the secondary supers.
tbz(r_bitmap, bit, L_fallthrough);
// Get the first array index that can contain super_klass into r_array_index.
if (bit != 0) {
shld(vtemp, vtemp, Klass::SECONDARY_SUPERS_TABLE_MASK - bit);
cnt(vtemp, T8B, vtemp);
addv(vtemp, T8B, vtemp);
fmovd(r_array_index, vtemp);
} else {
mov(r_array_index, (u1)1);
}
// NB! r_array_index is off by 1. It is compensated by keeping r_array_base off by 1 word.
// We will consult the secondary-super array.
ldr(r_array_base, Address(r_sub_klass, in_bytes(Klass::secondary_supers_offset())));
// The value i in r_array_index is >= 1, so even though r_array_base
// points to the length, we don't need to adjust it to point to the
// data.
assert(Array<Klass*>::base_offset_in_bytes() == wordSize, "Adjust this code");
assert(Array<Klass*>::length_offset_in_bytes() == 0, "Adjust this code");
ldr(result, Address(r_array_base, r_array_index, Address::lsl(LogBytesPerWord)));
eor(result, result, r_super_klass);
cbz(result, L_fallthrough); // Found a match
// Is there another entry to check? Consult the bitmap.
tbz(r_bitmap, (bit + 1) & Klass::SECONDARY_SUPERS_TABLE_MASK, L_fallthrough);
// Linear probe.
if (bit != 0) {
ror(r_bitmap, r_bitmap, bit);
}
// The slot we just inspected is at secondary_supers[r_array_index - 1].
// The next slot to be inspected, by the stub we're about to call,
// is secondary_supers[r_array_index]. Bits 0 and 1 in the bitmap
// have been checked.
Address stub = RuntimeAddress(StubRoutines::lookup_secondary_supers_table_slow_path_stub());
if (stub_is_near) {
bl(stub);
} else {
address call = trampoline_call(stub);
if (call == nullptr) {
return false; // trampoline allocation failed
}
}
BLOCK_COMMENT("} lookup_secondary_supers_table");
bind(L_fallthrough);
if (VerifySecondarySupers) {
verify_secondary_supers_table(r_sub_klass, r_super_klass, // r4, r0
temp1, temp2, result); // r1, r2, r5
}
return true;
}
// At runtime, return 0 in result if r_super_klass is a superclass of
// r_sub_klass, otherwise return nonzero. Use this version of
// lookup_secondary_supers_table() if you don't know ahead of time
// which superclass will be searched for. Used by interpreter and
// runtime stubs. It is larger and has somewhat greater latency than
// the version above, which takes a constant super_klass_slot.
void MacroAssembler::lookup_secondary_supers_table_var(Register r_sub_klass,
Register r_super_klass,
Register temp1,
Register temp2,
Register temp3,
FloatRegister vtemp,
Register result,
Label *L_success) {
assert_different_registers(r_sub_klass, temp1, temp2, temp3, result, rscratch1, rscratch2);
Label L_fallthrough;
BLOCK_COMMENT("lookup_secondary_supers_table {");
const Register
r_array_index = temp3,
slot = rscratch1,
r_bitmap = rscratch2;
ldrb(slot, Address(r_super_klass, Klass::hash_slot_offset()));
// Make sure that result is nonzero if the test below misses.
mov(result, 1);
ldr(r_bitmap, Address(r_sub_klass, Klass::secondary_supers_bitmap_offset()));
// First check the bitmap to see if super_klass might be present. If
// the bit is zero, we are certain that super_klass is not one of
// the secondary supers.
// This next instruction is equivalent to:
// mov(tmp_reg, (u1)(Klass::SECONDARY_SUPERS_TABLE_SIZE - 1));
// sub(temp2, tmp_reg, slot);
eor(temp2, slot, (u1)(Klass::SECONDARY_SUPERS_TABLE_SIZE - 1));
lslv(temp2, r_bitmap, temp2);
tbz(temp2, Klass::SECONDARY_SUPERS_TABLE_SIZE - 1, L_fallthrough);
bool must_save_v0 = (vtemp == fnoreg);
if (must_save_v0) {
// temp1 and result are free, so use them to preserve vtemp
vtemp = v0;
mov(temp1, vtemp, D, 0);
mov(result, vtemp, D, 1);
}
// Get the first array index that can contain super_klass into r_array_index.
mov(vtemp, D, 0, temp2);
cnt(vtemp, T8B, vtemp);
addv(vtemp, T8B, vtemp);
mov(r_array_index, vtemp, D, 0);
if (must_save_v0) {
mov(vtemp, D, 0, temp1 );
mov(vtemp, D, 1, result);
}
// NB! r_array_index is off by 1. It is compensated by keeping r_array_base off by 1 word.
const Register
r_array_base = temp1,
r_array_length = temp2;
// The value i in r_array_index is >= 1, so even though r_array_base
// points to the length, we don't need to adjust it to point to the
// data.
assert(Array<Klass*>::base_offset_in_bytes() == wordSize, "Adjust this code");
assert(Array<Klass*>::length_offset_in_bytes() == 0, "Adjust this code");
// We will consult the secondary-super array.
ldr(r_array_base, Address(r_sub_klass, in_bytes(Klass::secondary_supers_offset())));
ldr(result, Address(r_array_base, r_array_index, Address::lsl(LogBytesPerWord)));
eor(result, result, r_super_klass);
cbz(result, L_success ? *L_success : L_fallthrough); // Found a match
// Is there another entry to check? Consult the bitmap.
rorv(r_bitmap, r_bitmap, slot);
// rol(r_bitmap, r_bitmap, 1);
tbz(r_bitmap, 1, L_fallthrough);
// The slot we just inspected is at secondary_supers[r_array_index - 1].
// The next slot to be inspected, by the logic we're about to call,
// is secondary_supers[r_array_index]. Bits 0 and 1 in the bitmap
// have been checked.
lookup_secondary_supers_table_slow_path(r_super_klass, r_array_base, r_array_index,
r_bitmap, r_array_length, result, /*is_stub*/false);
BLOCK_COMMENT("} lookup_secondary_supers_table");
bind(L_fallthrough);
if (VerifySecondarySupers) {
verify_secondary_supers_table(r_sub_klass, r_super_klass, // r4, r0
temp1, temp2, result); // r1, r2, r5
}
if (L_success) {
cbz(result, *L_success);
}
}
// Called by code generated by check_klass_subtype_slow_path
// above. This is called when there is a collision in the hashed
// lookup in the secondary supers array.
void MacroAssembler::lookup_secondary_supers_table_slow_path(Register r_super_klass,
Register r_array_base,
Register r_array_index,
Register r_bitmap,
Register temp1,
Register result,
bool is_stub) {
assert_different_registers(r_super_klass, r_array_base, r_array_index, r_bitmap, temp1, result, rscratch1);
const Register
r_array_length = temp1,
r_sub_klass = noreg; // unused
if (is_stub) {
LOOKUP_SECONDARY_SUPERS_TABLE_REGISTERS;
}
Label L_fallthrough, L_huge;
// Load the array length.
ldrw(r_array_length, Address(r_array_base, Array<Klass*>::length_offset_in_bytes()));
// And adjust the array base to point to the data.
// NB! Effectively increments current slot index by 1.
assert(Array<Klass*>::base_offset_in_bytes() == wordSize, "");
add(r_array_base, r_array_base, Array<Klass*>::base_offset_in_bytes());
// The bitmap is full to bursting.
// Implicit invariant: BITMAP_FULL implies (length > 0)
assert(Klass::SECONDARY_SUPERS_BITMAP_FULL == ~uintx(0), "");
cmpw(r_array_length, (u1)(Klass::SECONDARY_SUPERS_TABLE_SIZE - 2));
br(GT, L_huge);
// NB! Our caller has checked bits 0 and 1 in the bitmap. The
// current slot (at secondary_supers[r_array_index]) has not yet
// been inspected, and r_array_index may be out of bounds if we
// wrapped around the end of the array.
{ // This is conventional linear probing, but instead of terminating
// when a null entry is found in the table, we maintain a bitmap
// in which a 0 indicates missing entries.
// As long as the bitmap is not completely full,
// array_length == popcount(bitmap). The array_length check above
// guarantees there are 0s in the bitmap, so the loop eventually
// terminates.
Label L_loop;
bind(L_loop);
// Check for wraparound.
cmp(r_array_index, r_array_length);
csel(r_array_index, zr, r_array_index, GE);
ldr(rscratch1, Address(r_array_base, r_array_index, Address::lsl(LogBytesPerWord)));
eor(result, rscratch1, r_super_klass);
cbz(result, L_fallthrough);
tbz(r_bitmap, 2, L_fallthrough); // look-ahead check (Bit 2); result is non-zero
ror(r_bitmap, r_bitmap, 1);
add(r_array_index, r_array_index, 1);
b(L_loop);
}
{ // Degenerate case: more than 64 secondary supers.
// FIXME: We could do something smarter here, maybe a vectorized
// comparison or a binary search, but is that worth any added
// complexity?
bind(L_huge);
cmp(sp, zr); // Clear Z flag; SP is never zero
repne_scan(r_array_base, r_super_klass, r_array_length, rscratch1);
cset(result, NE); // result == 0 iff we got a match.
}
bind(L_fallthrough);
}
// Make sure that the hashed lookup and a linear scan agree.
void MacroAssembler::verify_secondary_supers_table(Register r_sub_klass,
Register r_super_klass,
Register temp1,
Register temp2,
Register result) {
assert_different_registers(r_sub_klass, r_super_klass, temp1, temp2, result, rscratch1);
const Register
r_array_base = temp1,
r_array_length = temp2,
r_array_index = noreg, // unused
r_bitmap = noreg; // unused
BLOCK_COMMENT("verify_secondary_supers_table {");
// We will consult the secondary-super array.
ldr(r_array_base, Address(r_sub_klass, in_bytes(Klass::secondary_supers_offset())));
// Load the array length.
ldrw(r_array_length, Address(r_array_base, Array<Klass*>::length_offset_in_bytes()));
// And adjust the array base to point to the data.
add(r_array_base, r_array_base, Array<Klass*>::base_offset_in_bytes());
cmp(sp, zr); // Clear Z flag; SP is never zero
// Scan R2 words at [R5] for an occurrence of R0.
// Set NZ/Z based on last compare.
repne_scan(/*addr*/r_array_base, /*value*/r_super_klass, /*count*/r_array_length, rscratch2);
// rscratch1 == 0 iff we got a match.
cset(rscratch1, NE);
Label passed;
cmp(result, zr);
cset(result, NE); // normalize result to 0/1 for comparison
cmp(rscratch1, result);
br(EQ, passed);
{
mov(r0, r_super_klass); // r0 <- r0
mov(r1, r_sub_klass); // r1 <- r4
mov(r2, /*expected*/rscratch1); // r2 <- r8
mov(r3, result); // r3 <- r5
mov(r4, (address)("mismatch")); // r4 <- const
rt_call(CAST_FROM_FN_PTR(address, Klass::on_secondary_supers_verification_failure), rscratch2);
should_not_reach_here();
}
bind(passed);
BLOCK_COMMENT("} verify_secondary_supers_table");
}
void MacroAssembler::clinit_barrier(Register klass, Register scratch, Label* L_fast_path, Label* L_slow_path) {
assert(L_fast_path != nullptr || L_slow_path != nullptr, "at least one is required");
assert_different_registers(klass, rthread, scratch);
Label L_fallthrough, L_tmp;
if (L_fast_path == nullptr) {
L_fast_path = &L_fallthrough;
} else if (L_slow_path == nullptr) {
L_slow_path = &L_fallthrough;
}
// Fast path check: class is fully initialized
lea(scratch, Address(klass, InstanceKlass::init_state_offset()));
ldarb(scratch, scratch);
cmp(scratch, InstanceKlass::fully_initialized);
br(Assembler::EQ, *L_fast_path);
// Fast path check: current thread is initializer thread
ldr(scratch, Address(klass, InstanceKlass::init_thread_offset()));
cmp(rthread, scratch);
if (L_slow_path == &L_fallthrough) {
br(Assembler::EQ, *L_fast_path);
bind(*L_slow_path);
} else if (L_fast_path == &L_fallthrough) {
br(Assembler::NE, *L_slow_path);
bind(*L_fast_path);
} else {
Unimplemented();
}
}
void MacroAssembler::_verify_oop(Register reg, const char* s, const char* file, int line) {
if (!VerifyOops) return;
// Pass register number to verify_oop_subroutine
const char* b = nullptr;
{
ResourceMark rm;
stringStream ss;
ss.print("verify_oop: %s: %s (%s:%d)", reg->name(), s, file, line);
b = code_string(ss.as_string());
}
BLOCK_COMMENT("verify_oop {");
strip_return_address(); // This might happen within a stack frame.
protect_return_address();
stp(r0, rscratch1, Address(pre(sp, -2 * wordSize)));
stp(rscratch2, lr, Address(pre(sp, -2 * wordSize)));
mov(r0, reg);
movptr(rscratch1, (uintptr_t)(address)b);
// call indirectly to solve generation ordering problem
lea(rscratch2, RuntimeAddress(StubRoutines::verify_oop_subroutine_entry_address()));
ldr(rscratch2, Address(rscratch2));
blr(rscratch2);
ldp(rscratch2, lr, Address(post(sp, 2 * wordSize)));
ldp(r0, rscratch1, Address(post(sp, 2 * wordSize)));
authenticate_return_address();
BLOCK_COMMENT("} verify_oop");
}
void MacroAssembler::_verify_oop_addr(Address addr, const char* s, const char* file, int line) {
if (!VerifyOops) return;
const char* b = nullptr;
{
ResourceMark rm;
stringStream ss;
ss.print("verify_oop_addr: %s (%s:%d)", s, file, line);
b = code_string(ss.as_string());
}
BLOCK_COMMENT("verify_oop_addr {");
strip_return_address(); // This might happen within a stack frame.
protect_return_address();
stp(r0, rscratch1, Address(pre(sp, -2 * wordSize)));
stp(rscratch2, lr, Address(pre(sp, -2 * wordSize)));
// addr may contain sp so we will have to adjust it based on the
// pushes that we just did.
if (addr.uses(sp)) {
lea(r0, addr);
ldr(r0, Address(r0, 4 * wordSize));
} else {
ldr(r0, addr);
}
movptr(rscratch1, (uintptr_t)(address)b);
// call indirectly to solve generation ordering problem
lea(rscratch2, RuntimeAddress(StubRoutines::verify_oop_subroutine_entry_address()));
ldr(rscratch2, Address(rscratch2));
blr(rscratch2);
ldp(rscratch2, lr, Address(post(sp, 2 * wordSize)));
ldp(r0, rscratch1, Address(post(sp, 2 * wordSize)));
authenticate_return_address();
BLOCK_COMMENT("} verify_oop_addr");
}
Address MacroAssembler::argument_address(RegisterOrConstant arg_slot,
int extra_slot_offset) {
// cf. TemplateTable::prepare_invoke(), if (load_receiver).
int stackElementSize = Interpreter::stackElementSize;
int offset = Interpreter::expr_offset_in_bytes(extra_slot_offset+0);
#ifdef ASSERT
int offset1 = Interpreter::expr_offset_in_bytes(extra_slot_offset+1);
assert(offset1 - offset == stackElementSize, "correct arithmetic");
#endif
if (arg_slot.is_constant()) {
return Address(esp, arg_slot.as_constant() * stackElementSize
+ offset);
} else {
add(rscratch1, esp, arg_slot.as_register(),
ext::uxtx, exact_log2(stackElementSize));
return Address(rscratch1, offset);
}
}
void MacroAssembler::call_VM_leaf_base(address entry_point,
int number_of_arguments,
Label *retaddr) {
Label E, L;
stp(rscratch1, rmethod, Address(pre(sp, -2 * wordSize)));
mov(rscratch1, RuntimeAddress(entry_point));
blr(rscratch1);
if (retaddr)
bind(*retaddr);
ldp(rscratch1, rmethod, Address(post(sp, 2 * wordSize)));
}
void MacroAssembler::call_VM_leaf(address entry_point, int number_of_arguments) {
call_VM_leaf_base(entry_point, number_of_arguments);
}
void MacroAssembler::call_VM_leaf(address entry_point, Register arg_0) {
pass_arg0(this, arg_0);
call_VM_leaf_base(entry_point, 1);
}
void MacroAssembler::call_VM_leaf(address entry_point, Register arg_0, Register arg_1) {
assert_different_registers(arg_1, c_rarg0);
pass_arg0(this, arg_0);
pass_arg1(this, arg_1);
call_VM_leaf_base(entry_point, 2);
}
void MacroAssembler::call_VM_leaf(address entry_point, Register arg_0,
Register arg_1, Register arg_2) {
assert_different_registers(arg_1, c_rarg0);
assert_different_registers(arg_2, c_rarg0, c_rarg1);
pass_arg0(this, arg_0);
pass_arg1(this, arg_1);
pass_arg2(this, arg_2);
call_VM_leaf_base(entry_point, 3);
}
void MacroAssembler::super_call_VM_leaf(address entry_point, Register arg_0) {
pass_arg0(this, arg_0);
MacroAssembler::call_VM_leaf_base(entry_point, 1);
}
void MacroAssembler::super_call_VM_leaf(address entry_point, Register arg_0, Register arg_1) {
assert_different_registers(arg_0, c_rarg1);
pass_arg1(this, arg_1);
pass_arg0(this, arg_0);
MacroAssembler::call_VM_leaf_base(entry_point, 2);
}
void MacroAssembler::super_call_VM_leaf(address entry_point, Register arg_0, Register arg_1, Register arg_2) {
assert_different_registers(arg_0, c_rarg1, c_rarg2);
assert_different_registers(arg_1, c_rarg2);
pass_arg2(this, arg_2);
pass_arg1(this, arg_1);
pass_arg0(this, arg_0);
MacroAssembler::call_VM_leaf_base(entry_point, 3);
}
void MacroAssembler::super_call_VM_leaf(address entry_point, Register arg_0, Register arg_1, Register arg_2, Register arg_3) {
assert_different_registers(arg_0, c_rarg1, c_rarg2, c_rarg3);
assert_different_registers(arg_1, c_rarg2, c_rarg3);
assert_different_registers(arg_2, c_rarg3);
pass_arg3(this, arg_3);
pass_arg2(this, arg_2);
pass_arg1(this, arg_1);
pass_arg0(this, arg_0);
MacroAssembler::call_VM_leaf_base(entry_point, 4);
}
void MacroAssembler::null_check(Register reg, int offset) {
if (needs_explicit_null_check(offset)) {
// provoke OS null exception if reg is null by
// accessing M[reg] w/o changing any registers
// NOTE: this is plenty to provoke a segv
ldr(zr, Address(reg));
} else {
// nothing to do, (later) access of M[reg + offset]
// will provoke OS null exception if reg is null
}
}
// MacroAssembler protected routines needed to implement
// public methods
void MacroAssembler::mov(Register r, Address dest) {
code_section()->relocate(pc(), dest.rspec());
uint64_t imm64 = (uint64_t)dest.target();
movptr(r, imm64);
}
// Move a constant pointer into r. In AArch64 mode the virtual
// address space is 48 bits in size, so we only need three
// instructions to create a patchable instruction sequence that can
// reach anywhere.
void MacroAssembler::movptr(Register r, uintptr_t imm64) {
#ifndef PRODUCT
{
char buffer[64];
snprintf(buffer, sizeof(buffer), "0x%" PRIX64, (uint64_t)imm64);
block_comment(buffer);
}
#endif
assert(imm64 < (1ull << 48), "48-bit overflow in address constant");
movz(r, imm64 & 0xffff);
imm64 >>= 16;
movk(r, imm64 & 0xffff, 16);
imm64 >>= 16;
movk(r, imm64 & 0xffff, 32);
}
// Macro to mov replicated immediate to vector register.
// imm64: only the lower 8/16/32 bits are considered for B/H/S type. That is,
// the upper 56/48/32 bits must be zeros for B/H/S type.
// Vd will get the following values for different arrangements in T
// imm64 == hex 000000gh T8B: Vd = ghghghghghghghgh
// imm64 == hex 000000gh T16B: Vd = ghghghghghghghghghghghghghghghgh
// imm64 == hex 0000efgh T4H: Vd = efghefghefghefgh
// imm64 == hex 0000efgh T8H: Vd = efghefghefghefghefghefghefghefgh
// imm64 == hex abcdefgh T2S: Vd = abcdefghabcdefgh
// imm64 == hex abcdefgh T4S: Vd = abcdefghabcdefghabcdefghabcdefgh
// imm64 == hex abcdefgh T1D: Vd = 00000000abcdefgh
// imm64 == hex abcdefgh T2D: Vd = 00000000abcdefgh00000000abcdefgh
// Clobbers rscratch1
void MacroAssembler::mov(FloatRegister Vd, SIMD_Arrangement T, uint64_t imm64) {
assert(T != T1Q, "unsupported");
if (T == T1D || T == T2D) {
int imm = operand_valid_for_movi_immediate(imm64, T);
if (-1 != imm) {
movi(Vd, T, imm);
} else {
mov(rscratch1, imm64);
dup(Vd, T, rscratch1);
}
return;
}
#ifdef ASSERT
if (T == T8B || T == T16B) assert((imm64 & ~0xff) == 0, "extraneous bits (T8B/T16B)");
if (T == T4H || T == T8H) assert((imm64 & ~0xffff) == 0, "extraneous bits (T4H/T8H)");
if (T == T2S || T == T4S) assert((imm64 & ~0xffffffff) == 0, "extraneous bits (T2S/T4S)");
#endif
int shift = operand_valid_for_movi_immediate(imm64, T);
uint32_t imm32 = imm64 & 0xffffffffULL;
if (shift >= 0) {
movi(Vd, T, (imm32 >> shift) & 0xff, shift);
} else {
movw(rscratch1, imm32);
dup(Vd, T, rscratch1);
}
}
void MacroAssembler::mov_immediate64(Register dst, uint64_t imm64)
{
#ifndef PRODUCT
{
char buffer[64];
snprintf(buffer, sizeof(buffer), "0x%" PRIX64, imm64);
block_comment(buffer);
}
#endif
if (operand_valid_for_logical_immediate(false, imm64)) {
orr(dst, zr, imm64);
} else {
// we can use a combination of MOVZ or MOVN with
// MOVK to build up the constant
uint64_t imm_h[4];
int zero_count = 0;
int neg_count = 0;
int i;
for (i = 0; i < 4; i++) {
imm_h[i] = ((imm64 >> (i * 16)) & 0xffffL);
if (imm_h[i] == 0) {
zero_count++;
} else if (imm_h[i] == 0xffffL) {
neg_count++;
}
}
if (zero_count == 4) {
// one MOVZ will do
movz(dst, 0);
} else if (neg_count == 4) {
// one MOVN will do
movn(dst, 0);
} else if (zero_count == 3) {
for (i = 0; i < 4; i++) {
if (imm_h[i] != 0L) {
movz(dst, (uint32_t)imm_h[i], (i << 4));
break;
}
}
} else if (neg_count == 3) {
// one MOVN will do
for (int i = 0; i < 4; i++) {
if (imm_h[i] != 0xffffL) {
movn(dst, (uint32_t)imm_h[i] ^ 0xffffL, (i << 4));
break;
}
}
} else if (zero_count == 2) {
// one MOVZ and one MOVK will do
for (i = 0; i < 3; i++) {
if (imm_h[i] != 0L) {
movz(dst, (uint32_t)imm_h[i], (i << 4));
i++;
break;
}
}
for (;i < 4; i++) {
if (imm_h[i] != 0L) {
movk(dst, (uint32_t)imm_h[i], (i << 4));
}
}
} else if (neg_count == 2) {
// one MOVN and one MOVK will do
for (i = 0; i < 4; i++) {
if (imm_h[i] != 0xffffL) {
movn(dst, (uint32_t)imm_h[i] ^ 0xffffL, (i << 4));
i++;
break;
}
}
for (;i < 4; i++) {
if (imm_h[i] != 0xffffL) {
movk(dst, (uint32_t)imm_h[i], (i << 4));
}
}
} else if (zero_count == 1) {
// one MOVZ and two MOVKs will do
for (i = 0; i < 4; i++) {
if (imm_h[i] != 0L) {
movz(dst, (uint32_t)imm_h[i], (i << 4));
i++;
break;
}
}
for (;i < 4; i++) {
if (imm_h[i] != 0x0L) {
movk(dst, (uint32_t)imm_h[i], (i << 4));
}
}
} else if (neg_count == 1) {
// one MOVN and two MOVKs will do
for (i = 0; i < 4; i++) {
if (imm_h[i] != 0xffffL) {
movn(dst, (uint32_t)imm_h[i] ^ 0xffffL, (i << 4));
i++;
break;
}
}
for (;i < 4; i++) {
if (imm_h[i] != 0xffffL) {
movk(dst, (uint32_t)imm_h[i], (i << 4));
}
}
} else {
// use a MOVZ and 3 MOVKs (makes it easier to debug)
movz(dst, (uint32_t)imm_h[0], 0);
for (i = 1; i < 4; i++) {
movk(dst, (uint32_t)imm_h[i], (i << 4));
}
}
}
}
void MacroAssembler::mov_immediate32(Register dst, uint32_t imm32)
{
#ifndef PRODUCT
{
char buffer[64];
snprintf(buffer, sizeof(buffer), "0x%" PRIX32, imm32);
block_comment(buffer);
}
#endif
if (operand_valid_for_logical_immediate(true, imm32)) {
orrw(dst, zr, imm32);
} else {
// we can use MOVZ, MOVN or two calls to MOVK to build up the
// constant
uint32_t imm_h[2];
imm_h[0] = imm32 & 0xffff;
imm_h[1] = ((imm32 >> 16) & 0xffff);
if (imm_h[0] == 0) {
movzw(dst, imm_h[1], 16);
} else if (imm_h[0] == 0xffff) {
movnw(dst, imm_h[1] ^ 0xffff, 16);
} else if (imm_h[1] == 0) {
movzw(dst, imm_h[0], 0);
} else if (imm_h[1] == 0xffff) {
movnw(dst, imm_h[0] ^ 0xffff, 0);
} else {
// use a MOVZ and MOVK (makes it easier to debug)
movzw(dst, imm_h[0], 0);
movkw(dst, imm_h[1], 16);
}
}
}
// Form an address from base + offset in Rd. Rd may or may
// not actually be used: you must use the Address that is returned.
// It is up to you to ensure that the shift provided matches the size
// of your data.
Address MacroAssembler::form_address(Register Rd, Register base, int64_t byte_offset, int shift) {
if (Address::offset_ok_for_immed(byte_offset, shift))
// It fits; no need for any heroics
return Address(base, byte_offset);
// Don't do anything clever with negative or misaligned offsets
unsigned mask = (1 << shift) - 1;
if (byte_offset < 0 || byte_offset & mask) {
mov(Rd, byte_offset);
add(Rd, base, Rd);
return Address(Rd);
}
// See if we can do this with two 12-bit offsets
{
uint64_t word_offset = byte_offset >> shift;
uint64_t masked_offset = word_offset & 0xfff000;
if (Address::offset_ok_for_immed(word_offset - masked_offset, 0)
&& Assembler::operand_valid_for_add_sub_immediate(masked_offset << shift)) {
add(Rd, base, masked_offset << shift);
word_offset -= masked_offset;
return Address(Rd, word_offset << shift);
}
}
// Do it the hard way
mov(Rd, byte_offset);
add(Rd, base, Rd);
return Address(Rd);
}
int MacroAssembler::corrected_idivl(Register result, Register ra, Register rb,
bool want_remainder, Register scratch)
{
// Full implementation of Java idiv and irem. The function
// returns the (pc) offset of the div instruction - may be needed
// for implicit exceptions.
//
// constraint : ra/rb =/= scratch
// normal case
//
// input : ra: dividend
// rb: divisor
//
// result: either
// quotient (= ra idiv rb)
// remainder (= ra irem rb)
assert(ra != scratch && rb != scratch, "reg cannot be scratch");
int idivl_offset = offset();
if (! want_remainder) {
sdivw(result, ra, rb);
} else {
sdivw(scratch, ra, rb);
Assembler::msubw(result, scratch, rb, ra);
}
return idivl_offset;
}
int MacroAssembler::corrected_idivq(Register result, Register ra, Register rb,
bool want_remainder, Register scratch)
{
// Full implementation of Java ldiv and lrem. The function
// returns the (pc) offset of the div instruction - may be needed
// for implicit exceptions.
//
// constraint : ra/rb =/= scratch
// normal case
//
// input : ra: dividend
// rb: divisor
//
// result: either
// quotient (= ra idiv rb)
// remainder (= ra irem rb)
assert(ra != scratch && rb != scratch, "reg cannot be scratch");
int idivq_offset = offset();
if (! want_remainder) {
sdiv(result, ra, rb);
} else {
sdiv(scratch, ra, rb);
Assembler::msub(result, scratch, rb, ra);
}
return idivq_offset;
}
void MacroAssembler::membar(Membar_mask_bits order_constraint) {
address prev = pc() - NativeMembar::instruction_size;
address last = code()->last_insn();
if (last != nullptr && nativeInstruction_at(last)->is_Membar() && prev == last) {
NativeMembar *bar = NativeMembar_at(prev);
if (AlwaysMergeDMB) {
bar->set_kind(bar->get_kind() | order_constraint);
BLOCK_COMMENT("merged membar(always)");
return;
}
// Don't promote DMB ST|DMB LD to DMB (a full barrier) because
// doing so would introduce a StoreLoad which the caller did not
// intend
if (bar->get_kind() == order_constraint
|| bar->get_kind() == AnyAny
|| order_constraint == AnyAny) {
// We are merging two memory barrier instructions. On AArch64 we
// can do this simply by ORing them together.
bar->set_kind(bar->get_kind() | order_constraint);
BLOCK_COMMENT("merged membar");
return;
} else {
// A special case like "DMB ST;DMB LD;DMB ST", the last DMB can be skipped
// We need check the last 2 instructions
address prev2 = prev - NativeMembar::instruction_size;
if (last != code()->last_label() && nativeInstruction_at(prev2)->is_Membar()) {
NativeMembar *bar2 = NativeMembar_at(prev2);
assert(bar2->get_kind() == order_constraint, "it should be merged before");
BLOCK_COMMENT("merged membar(elided)");
return;
}
}
}
code()->set_last_insn(pc());
dmb(Assembler::barrier(order_constraint));
}
bool MacroAssembler::try_merge_ldst(Register rt, const Address &adr, size_t size_in_bytes, bool is_store) {
if (ldst_can_merge(rt, adr, size_in_bytes, is_store)) {
merge_ldst(rt, adr, size_in_bytes, is_store);
code()->clear_last_insn();
return true;
} else {
assert(size_in_bytes == 8 || size_in_bytes == 4, "only 8 bytes or 4 bytes load/store is supported.");
const uint64_t mask = size_in_bytes - 1;
if (adr.getMode() == Address::base_plus_offset &&
(adr.offset() & mask) == 0) { // only supports base_plus_offset.
code()->set_last_insn(pc());
}
return false;
}
}
void MacroAssembler::ldr(Register Rx, const Address &adr) {
// We always try to merge two adjacent loads into one ldp.
if (!try_merge_ldst(Rx, adr, 8, false)) {
Assembler::ldr(Rx, adr);
}
}
void MacroAssembler::ldrw(Register Rw, const Address &adr) {
// We always try to merge two adjacent loads into one ldp.
if (!try_merge_ldst(Rw, adr, 4, false)) {
Assembler::ldrw(Rw, adr);
}
}
void MacroAssembler::str(Register Rx, const Address &adr) {
// We always try to merge two adjacent stores into one stp.
if (!try_merge_ldst(Rx, adr, 8, true)) {
Assembler::str(Rx, adr);
}
}
void MacroAssembler::strw(Register Rw, const Address &adr) {
// We always try to merge two adjacent stores into one stp.
if (!try_merge_ldst(Rw, adr, 4, true)) {
Assembler::strw(Rw, adr);
}
}
// MacroAssembler routines found actually to be needed
void MacroAssembler::push(Register src)
{
str(src, Address(pre(esp, -1 * wordSize)));
}
void MacroAssembler::pop(Register dst)
{
ldr(dst, Address(post(esp, 1 * wordSize)));
}
// Note: load_unsigned_short used to be called load_unsigned_word.
int MacroAssembler::load_unsigned_short(Register dst, Address src) {
int off = offset();
ldrh(dst, src);
return off;
}
int MacroAssembler::load_unsigned_byte(Register dst, Address src) {
int off = offset();
ldrb(dst, src);
return off;
}
int MacroAssembler::load_signed_short(Register dst, Address src) {
int off = offset();
ldrsh(dst, src);
return off;
}
int MacroAssembler::load_signed_byte(Register dst, Address src) {
int off = offset();
ldrsb(dst, src);
return off;
}
int MacroAssembler::load_signed_short32(Register dst, Address src) {
int off = offset();
ldrshw(dst, src);
return off;
}
int MacroAssembler::load_signed_byte32(Register dst, Address src) {
int off = offset();
ldrsbw(dst, src);
return off;
}
void MacroAssembler::load_sized_value(Register dst, Address src, size_t size_in_bytes, bool is_signed) {
switch (size_in_bytes) {
case 8: ldr(dst, src); break;
case 4: ldrw(dst, src); break;
case 2: is_signed ? load_signed_short(dst, src) : load_unsigned_short(dst, src); break;
case 1: is_signed ? load_signed_byte( dst, src) : load_unsigned_byte( dst, src); break;
default: ShouldNotReachHere();
}
}
void MacroAssembler::store_sized_value(Address dst, Register src, size_t size_in_bytes) {
switch (size_in_bytes) {
case 8: str(src, dst); break;
case 4: strw(src, dst); break;
case 2: strh(src, dst); break;
case 1: strb(src, dst); break;
default: ShouldNotReachHere();
}
}
void MacroAssembler::decrementw(Register reg, int value)
{
if (value < 0) { incrementw(reg, -value); return; }
if (value == 0) { return; }
if (value < (1 << 12)) { subw(reg, reg, value); return; }
/* else */ {
guarantee(reg != rscratch2, "invalid dst for register decrement");
movw(rscratch2, (unsigned)value);
subw(reg, reg, rscratch2);
}
}
void MacroAssembler::decrement(Register reg, int value)
{
if (value < 0) { increment(reg, -value); return; }
if (value == 0) { return; }
if (value < (1 << 12)) { sub(reg, reg, value); return; }
/* else */ {
assert(reg != rscratch2, "invalid dst for register decrement");
mov(rscratch2, (uint64_t)value);
sub(reg, reg, rscratch2);
}
}
void MacroAssembler::decrementw(Address dst, int value)
{
assert(!dst.uses(rscratch1), "invalid dst for address decrement");
if (dst.getMode() == Address::literal) {
assert(abs(value) < (1 << 12), "invalid value and address mode combination");
lea(rscratch2, dst);
dst = Address(rscratch2);
}
ldrw(rscratch1, dst);
decrementw(rscratch1, value);
strw(rscratch1, dst);
}
void MacroAssembler::decrement(Address dst, int value)
{
assert(!dst.uses(rscratch1), "invalid address for decrement");
if (dst.getMode() == Address::literal) {
assert(abs(value) < (1 << 12), "invalid value and address mode combination");
lea(rscratch2, dst);
dst = Address(rscratch2);
}
ldr(rscratch1, dst);
decrement(rscratch1, value);
str(rscratch1, dst);
}
void MacroAssembler::incrementw(Register reg, int value)
{
if (value < 0) { decrementw(reg, -value); return; }
if (value == 0) { return; }
if (value < (1 << 12)) { addw(reg, reg, value); return; }
/* else */ {
assert(reg != rscratch2, "invalid dst for register increment");
movw(rscratch2, (unsigned)value);
addw(reg, reg, rscratch2);
}
}
void MacroAssembler::increment(Register reg, int value)
{
if (value < 0) { decrement(reg, -value); return; }
if (value == 0) { return; }
if (value < (1 << 12)) { add(reg, reg, value); return; }
/* else */ {
assert(reg != rscratch2, "invalid dst for register increment");
movw(rscratch2, (unsigned)value);
add(reg, reg, rscratch2);
}
}
void MacroAssembler::incrementw(Address dst, int value)
{
assert(!dst.uses(rscratch1), "invalid dst for address increment");
if (dst.getMode() == Address::literal) {
assert(abs(value) < (1 << 12), "invalid value and address mode combination");
lea(rscratch2, dst);
dst = Address(rscratch2);
}
ldrw(rscratch1, dst);
incrementw(rscratch1, value);
strw(rscratch1, dst);
}
void MacroAssembler::increment(Address dst, int value)
{
assert(!dst.uses(rscratch1), "invalid dst for address increment");
if (dst.getMode() == Address::literal) {
assert(abs(value) < (1 << 12), "invalid value and address mode combination");
lea(rscratch2, dst);
dst = Address(rscratch2);
}
ldr(rscratch1, dst);
increment(rscratch1, value);
str(rscratch1, dst);
}
// Push lots of registers in the bit set supplied. Don't push sp.
// Return the number of words pushed
int MacroAssembler::push(unsigned int bitset, Register stack) {
int words_pushed = 0;
// Scan bitset to accumulate register pairs
unsigned char regs[32];
int count = 0;
for (int reg = 0; reg <= 30; reg++) {
if (1 & bitset)
regs[count++] = reg;
bitset >>= 1;
}
regs[count++] = zr->raw_encoding();
count &= ~1; // Only push an even number of regs
if (count) {
stp(as_Register(regs[0]), as_Register(regs[1]),
Address(pre(stack, -count * wordSize)));
words_pushed += 2;
}
for (int i = 2; i < count; i += 2) {
stp(as_Register(regs[i]), as_Register(regs[i+1]),
Address(stack, i * wordSize));
words_pushed += 2;
}
assert(words_pushed == count, "oops, pushed != count");
return count;
}
int MacroAssembler::pop(unsigned int bitset, Register stack) {
int words_pushed = 0;
// Scan bitset to accumulate register pairs
unsigned char regs[32];
int count = 0;
for (int reg = 0; reg <= 30; reg++) {
if (1 & bitset)
regs[count++] = reg;
bitset >>= 1;
}
regs[count++] = zr->raw_encoding();
count &= ~1;
for (int i = 2; i < count; i += 2) {
ldp(as_Register(regs[i]), as_Register(regs[i+1]),
Address(stack, i * wordSize));
words_pushed += 2;
}
if (count) {
ldp(as_Register(regs[0]), as_Register(regs[1]),
Address(post(stack, count * wordSize)));
words_pushed += 2;
}
assert(words_pushed == count, "oops, pushed != count");
return count;
}
// Push lots of registers in the bit set supplied. Don't push sp.
// Return the number of dwords pushed
int MacroAssembler::push_fp(unsigned int bitset, Register stack, FpPushPopMode mode) {
int words_pushed = 0;
bool use_sve = false;
int sve_vector_size_in_bytes = 0;
#ifdef COMPILER2
use_sve = Matcher::supports_scalable_vector();
sve_vector_size_in_bytes = Matcher::scalable_vector_reg_size(T_BYTE);
#endif
// Scan bitset to accumulate register pairs
unsigned char regs[32];
int count = 0;
for (int reg = 0; reg <= 31; reg++) {
if (1 & bitset)
regs[count++] = reg;
bitset >>= 1;
}
if (count == 0) {
return 0;
}
if (mode == PushPopFull) {
if (use_sve && sve_vector_size_in_bytes > 16) {
mode = PushPopSVE;
} else {
mode = PushPopNeon;
}
}
#ifndef PRODUCT
{
char buffer[48];
if (mode == PushPopSVE) {
snprintf(buffer, sizeof(buffer), "push_fp: %d SVE registers", count);
} else if (mode == PushPopNeon) {
snprintf(buffer, sizeof(buffer), "push_fp: %d Neon registers", count);
} else {
snprintf(buffer, sizeof(buffer), "push_fp: %d fp registers", count);
}
block_comment(buffer);
}
#endif
if (mode == PushPopSVE) {
sub(stack, stack, sve_vector_size_in_bytes * count);
for (int i = 0; i < count; i++) {
sve_str(as_FloatRegister(regs[i]), Address(stack, i));
}
return count * sve_vector_size_in_bytes / 8;
}
if (mode == PushPopNeon) {
if (count == 1) {
strq(as_FloatRegister(regs[0]), Address(pre(stack, -wordSize * 2)));
return 2;
}
bool odd = (count & 1) == 1;
int push_slots = count + (odd ? 1 : 0);
// Always pushing full 128 bit registers.
stpq(as_FloatRegister(regs[0]), as_FloatRegister(regs[1]), Address(pre(stack, -push_slots * wordSize * 2)));
words_pushed += 2;
for (int i = 2; i + 1 < count; i += 2) {
stpq(as_FloatRegister(regs[i]), as_FloatRegister(regs[i+1]), Address(stack, i * wordSize * 2));
words_pushed += 2;
}
if (odd) {
strq(as_FloatRegister(regs[count - 1]), Address(stack, (count - 1) * wordSize * 2));
words_pushed++;
}
assert(words_pushed == count, "oops, pushed(%d) != count(%d)", words_pushed, count);
return count * 2;
}
if (mode == PushPopFp) {
bool odd = (count & 1) == 1;
int push_slots = count + (odd ? 1 : 0);
if (count == 1) {
// Stack pointer must be 16 bytes aligned
strd(as_FloatRegister(regs[0]), Address(pre(stack, -push_slots * wordSize)));
return 1;
}
stpd(as_FloatRegister(regs[0]), as_FloatRegister(regs[1]), Address(pre(stack, -push_slots * wordSize)));
words_pushed += 2;
for (int i = 2; i + 1 < count; i += 2) {
stpd(as_FloatRegister(regs[i]), as_FloatRegister(regs[i+1]), Address(stack, i * wordSize));
words_pushed += 2;
}
if (odd) {
// Stack pointer must be 16 bytes aligned
strd(as_FloatRegister(regs[count - 1]), Address(stack, (count - 1) * wordSize));
words_pushed++;
}
assert(words_pushed == count, "oops, pushed != count");
return count;
}
return 0;
}
// Return the number of dwords popped
int MacroAssembler::pop_fp(unsigned int bitset, Register stack, FpPushPopMode mode) {
int words_pushed = 0;
bool use_sve = false;
int sve_vector_size_in_bytes = 0;
#ifdef COMPILER2
use_sve = Matcher::supports_scalable_vector();
sve_vector_size_in_bytes = Matcher::scalable_vector_reg_size(T_BYTE);
#endif
// Scan bitset to accumulate register pairs
unsigned char regs[32];
int count = 0;
for (int reg = 0; reg <= 31; reg++) {
if (1 & bitset)
regs[count++] = reg;
bitset >>= 1;
}
if (count == 0) {
return 0;
}
if (mode == PushPopFull) {
if (use_sve && sve_vector_size_in_bytes > 16) {
mode = PushPopSVE;
} else {
mode = PushPopNeon;
}
}
#ifndef PRODUCT
{
char buffer[48];
if (mode == PushPopSVE) {
snprintf(buffer, sizeof(buffer), "pop_fp: %d SVE registers", count);
} else if (mode == PushPopNeon) {
snprintf(buffer, sizeof(buffer), "pop_fp: %d Neon registers", count);
} else {
snprintf(buffer, sizeof(buffer), "pop_fp: %d fp registers", count);
}
block_comment(buffer);
}
#endif
if (mode == PushPopSVE) {
for (int i = count - 1; i >= 0; i--) {
sve_ldr(as_FloatRegister(regs[i]), Address(stack, i));
}
add(stack, stack, sve_vector_size_in_bytes * count);
return count * sve_vector_size_in_bytes / 8;
}
if (mode == PushPopNeon) {
if (count == 1) {
ldrq(as_FloatRegister(regs[0]), Address(post(stack, wordSize * 2)));
return 2;
}
bool odd = (count & 1) == 1;
int push_slots = count + (odd ? 1 : 0);
if (odd) {
ldrq(as_FloatRegister(regs[count - 1]), Address(stack, (count - 1) * wordSize * 2));
words_pushed++;
}
for (int i = 2; i + 1 < count; i += 2) {
ldpq(as_FloatRegister(regs[i]), as_FloatRegister(regs[i+1]), Address(stack, i * wordSize * 2));
words_pushed += 2;
}
ldpq(as_FloatRegister(regs[0]), as_FloatRegister(regs[1]), Address(post(stack, push_slots * wordSize * 2)));
words_pushed += 2;
assert(words_pushed == count, "oops, pushed(%d) != count(%d)", words_pushed, count);
return count * 2;
}
if (mode == PushPopFp) {
bool odd = (count & 1) == 1;
int push_slots = count + (odd ? 1 : 0);
if (count == 1) {
ldrd(as_FloatRegister(regs[0]), Address(post(stack, push_slots * wordSize)));
return 1;
}
if (odd) {
ldrd(as_FloatRegister(regs[count - 1]), Address(stack, (count - 1) * wordSize));
words_pushed++;
}
for (int i = 2; i + 1 < count; i += 2) {
ldpd(as_FloatRegister(regs[i]), as_FloatRegister(regs[i+1]), Address(stack, i * wordSize));
words_pushed += 2;
}
ldpd(as_FloatRegister(regs[0]), as_FloatRegister(regs[1]), Address(post(stack, push_slots * wordSize)));
words_pushed += 2;
assert(words_pushed == count, "oops, pushed != count");
return count;
}
return 0;
}
// Return the number of dwords pushed
int MacroAssembler::push_p(unsigned int bitset, Register stack) {
bool use_sve = false;
int sve_predicate_size_in_slots = 0;
#ifdef COMPILER2
use_sve = Matcher::supports_scalable_vector();
if (use_sve) {
sve_predicate_size_in_slots = Matcher::scalable_predicate_reg_slots();
}
#endif
if (!use_sve) {
return 0;
}
unsigned char regs[PRegister::number_of_registers];
int count = 0;
for (int reg = 0; reg < PRegister::number_of_registers; reg++) {
if (1 & bitset)
regs[count++] = reg;
bitset >>= 1;
}
if (count == 0) {
return 0;
}
int total_push_bytes = align_up(sve_predicate_size_in_slots *
VMRegImpl::stack_slot_size * count, 16);
sub(stack, stack, total_push_bytes);
for (int i = 0; i < count; i++) {
sve_str(as_PRegister(regs[i]), Address(stack, i));
}
return total_push_bytes / 8;
}
// Return the number of dwords popped
int MacroAssembler::pop_p(unsigned int bitset, Register stack) {
bool use_sve = false;
int sve_predicate_size_in_slots = 0;
#ifdef COMPILER2
use_sve = Matcher::supports_scalable_vector();
if (use_sve) {
sve_predicate_size_in_slots = Matcher::scalable_predicate_reg_slots();
}
#endif
if (!use_sve) {
return 0;
}
unsigned char regs[PRegister::number_of_registers];
int count = 0;
for (int reg = 0; reg < PRegister::number_of_registers; reg++) {
if (1 & bitset)
regs[count++] = reg;
bitset >>= 1;
}
if (count == 0) {
return 0;
}
int total_pop_bytes = align_up(sve_predicate_size_in_slots *
VMRegImpl::stack_slot_size * count, 16);
for (int i = count - 1; i >= 0; i--) {
sve_ldr(as_PRegister(regs[i]), Address(stack, i));
}
add(stack, stack, total_pop_bytes);
return total_pop_bytes / 8;
}
#ifdef ASSERT
void MacroAssembler::verify_heapbase(const char* msg) {
#if 0
assert (UseCompressedOops || UseCompressedClassPointers, "should be compressed");
assert (Universe::heap() != nullptr, "java heap should be initialized");
if (!UseCompressedOops || Universe::ptr_base() == nullptr) {
// rheapbase is allocated as general register
return;
}
if (CheckCompressedOops) {
Label ok;
push(1 << rscratch1->encoding(), sp); // cmpptr trashes rscratch1
cmpptr(rheapbase, ExternalAddress(CompressedOops::base_addr()));
br(Assembler::EQ, ok);
stop(msg);
bind(ok);
pop(1 << rscratch1->encoding(), sp);
}
#endif
}
#endif
void MacroAssembler::resolve_jobject(Register value, Register tmp1, Register tmp2) {
assert_different_registers(value, tmp1, tmp2);
Label done, tagged, weak_tagged;
cbz(value, done); // Use null as-is.
tst(value, JNIHandles::tag_mask); // Test for tag.
br(Assembler::NE, tagged);
// Resolve local handle
access_load_at(T_OBJECT, IN_NATIVE | AS_RAW, value, Address(value, 0), tmp1, tmp2);
verify_oop(value);
b(done);
bind(tagged);
STATIC_ASSERT(JNIHandles::TypeTag::weak_global == 0b1);
tbnz(value, 0, weak_tagged); // Test for weak tag.
// Resolve global handle
access_load_at(T_OBJECT, IN_NATIVE, value, Address(value, -JNIHandles::TypeTag::global), tmp1, tmp2);
verify_oop(value);
b(done);
bind(weak_tagged);
// Resolve jweak.
access_load_at(T_OBJECT, IN_NATIVE | ON_PHANTOM_OOP_REF,
value, Address(value, -JNIHandles::TypeTag::weak_global), tmp1, tmp2);
verify_oop(value);
bind(done);
}
void MacroAssembler::resolve_global_jobject(Register value, Register tmp1, Register tmp2) {
assert_different_registers(value, tmp1, tmp2);
Label done;
cbz(value, done); // Use null as-is.
#ifdef ASSERT
{
STATIC_ASSERT(JNIHandles::TypeTag::global == 0b10);
Label valid_global_tag;
tbnz(value, 1, valid_global_tag); // Test for global tag
stop("non global jobject using resolve_global_jobject");
bind(valid_global_tag);
}
#endif
// Resolve global handle
access_load_at(T_OBJECT, IN_NATIVE, value, Address(value, -JNIHandles::TypeTag::global), tmp1, tmp2);
verify_oop(value);
bind(done);
}
void MacroAssembler::stop(const char* msg) {
// Skip AOT caching C strings in scratch buffer.
const char* str = (code_section()->scratch_emit()) ? msg : AOTCodeCache::add_C_string(msg);
BLOCK_COMMENT(str);
// load msg into r0 so we can access it from the signal handler
// ExternalAddress enables saving and restoring via the code cache
lea(c_rarg0, ExternalAddress((address) str));
dcps1(0xdeae);
}
void MacroAssembler::unimplemented(const char* what) {
const char* buf = nullptr;
{
ResourceMark rm;
stringStream ss;
ss.print("unimplemented: %s", what);
buf = code_string(ss.as_string());
}
stop(buf);
}
void MacroAssembler::_assert_asm(Assembler::Condition cc, const char* msg) {
#ifdef ASSERT
Label OK;
br(cc, OK);
stop(msg);
bind(OK);
#endif
}
// If a constant does not fit in an immediate field, generate some
// number of MOV instructions and then perform the operation.
void MacroAssembler::wrap_add_sub_imm_insn(Register Rd, Register Rn, uint64_t imm,
add_sub_imm_insn insn1,
add_sub_reg_insn insn2,
bool is32) {
assert(Rd != zr, "Rd = zr and not setting flags?");
bool fits = operand_valid_for_add_sub_immediate(is32 ? (int32_t)imm : imm);
if (fits) {
(this->*insn1)(Rd, Rn, imm);
} else {
if (g_uabs(imm) < (1 << 24)) {
(this->*insn1)(Rd, Rn, imm & -(1 << 12));
(this->*insn1)(Rd, Rd, imm & ((1 << 12)-1));
} else {
assert_different_registers(Rd, Rn);
mov(Rd, imm);
(this->*insn2)(Rd, Rn, Rd, LSL, 0);
}
}
}
// Separate vsn which sets the flags. Optimisations are more restricted
// because we must set the flags correctly.
void MacroAssembler::wrap_adds_subs_imm_insn(Register Rd, Register Rn, uint64_t imm,
add_sub_imm_insn insn1,
add_sub_reg_insn insn2,
bool is32) {
bool fits = operand_valid_for_add_sub_immediate(is32 ? (int32_t)imm : imm);
if (fits) {
(this->*insn1)(Rd, Rn, imm);
} else {
assert_different_registers(Rd, Rn);
assert(Rd != zr, "overflow in immediate operand");
mov(Rd, imm);
(this->*insn2)(Rd, Rn, Rd, LSL, 0);
}
}
void MacroAssembler::add(Register Rd, Register Rn, RegisterOrConstant increment) {
if (increment.is_register()) {
add(Rd, Rn, increment.as_register());
} else {
add(Rd, Rn, increment.as_constant());
}
}
void MacroAssembler::addw(Register Rd, Register Rn, RegisterOrConstant increment) {
if (increment.is_register()) {
addw(Rd, Rn, increment.as_register());
} else {
addw(Rd, Rn, increment.as_constant());
}
}
void MacroAssembler::sub(Register Rd, Register Rn, RegisterOrConstant decrement) {
if (decrement.is_register()) {
sub(Rd, Rn, decrement.as_register());
} else {
sub(Rd, Rn, decrement.as_constant());
}
}
void MacroAssembler::subw(Register Rd, Register Rn, RegisterOrConstant decrement) {
if (decrement.is_register()) {
subw(Rd, Rn, decrement.as_register());
} else {
subw(Rd, Rn, decrement.as_constant());
}
}
void MacroAssembler::reinit_heapbase()
{
if (UseCompressedOops) {
if (Universe::is_fully_initialized()) {
mov(rheapbase, CompressedOops::base());
} else {
lea(rheapbase, ExternalAddress(CompressedOops::base_addr()));
ldr(rheapbase, Address(rheapbase));
}
}
}
// this simulates the behaviour of the x86 cmpxchg instruction using a
// load linked/store conditional pair. we use the acquire/release
// versions of these instructions so that we flush pending writes as
// per Java semantics.
// n.b the x86 version assumes the old value to be compared against is
// in rax and updates rax with the value located in memory if the
// cmpxchg fails. we supply a register for the old value explicitly
// the aarch64 load linked/store conditional instructions do not
// accept an offset. so, unlike x86, we must provide a plain register
// to identify the memory word to be compared/exchanged rather than a
// register+offset Address.
void MacroAssembler::cmpxchgptr(Register oldv, Register newv, Register addr, Register tmp,
Label &succeed, Label *fail) {
// oldv holds comparison value
// newv holds value to write in exchange
// addr identifies memory word to compare against/update
if (UseLSE) {
mov(tmp, oldv);
casal(Assembler::xword, oldv, newv, addr);
cmp(tmp, oldv);
br(Assembler::EQ, succeed);
membar(AnyAny);
} else {
Label retry_load, nope;
prfm(Address(addr), PSTL1STRM);
bind(retry_load);
// flush and load exclusive from the memory location
// and fail if it is not what we expect
ldaxr(tmp, addr);
cmp(tmp, oldv);
br(Assembler::NE, nope);
// if we store+flush with no intervening write tmp will be zero
stlxr(tmp, newv, addr);
cbzw(tmp, succeed);
// retry so we only ever return after a load fails to compare
// ensures we don't return a stale value after a failed write.
b(retry_load);
// if the memory word differs we return it in oldv and signal a fail
bind(nope);
membar(AnyAny);
mov(oldv, tmp);
}
if (fail)
b(*fail);
}
void MacroAssembler::cmpxchg_obj_header(Register oldv, Register newv, Register obj, Register tmp,
Label &succeed, Label *fail) {
assert(oopDesc::mark_offset_in_bytes() == 0, "assumption");
cmpxchgptr(oldv, newv, obj, tmp, succeed, fail);
}
void MacroAssembler::cmpxchgw(Register oldv, Register newv, Register addr, Register tmp,
Label &succeed, Label *fail) {
// oldv holds comparison value
// newv holds value to write in exchange
// addr identifies memory word to compare against/update
// tmp returns 0/1 for success/failure
if (UseLSE) {
mov(tmp, oldv);
casal(Assembler::word, oldv, newv, addr);
cmp(tmp, oldv);
br(Assembler::EQ, succeed);
membar(AnyAny);
} else {
Label retry_load, nope;
prfm(Address(addr), PSTL1STRM);
bind(retry_load);
// flush and load exclusive from the memory location
// and fail if it is not what we expect
ldaxrw(tmp, addr);
cmp(tmp, oldv);
br(Assembler::NE, nope);
// if we store+flush with no intervening write tmp will be zero
stlxrw(tmp, newv, addr);
cbzw(tmp, succeed);
// retry so we only ever return after a load fails to compare
// ensures we don't return a stale value after a failed write.
b(retry_load);
// if the memory word differs we return it in oldv and signal a fail
bind(nope);
membar(AnyAny);
mov(oldv, tmp);
}
if (fail)
b(*fail);
}
// A generic CAS; success or failure is in the EQ flag. A weak CAS
// doesn't retry and may fail spuriously. If the oldval is wanted,
// Pass a register for the result, otherwise pass noreg.
// Clobbers rscratch1
void MacroAssembler::cmpxchg(Register addr, Register expected,
Register new_val,
enum operand_size size,
bool acquire, bool release,
bool weak,
Register result) {
if (result == noreg) result = rscratch1;
BLOCK_COMMENT("cmpxchg {");
if (UseLSE) {
mov(result, expected);
lse_cas(result, new_val, addr, size, acquire, release, /*not_pair*/ true);
compare_eq(result, expected, size);
#ifdef ASSERT
// Poison rscratch1 which is written on !UseLSE branch
mov(rscratch1, 0x1f1f1f1f1f1f1f1f);
#endif
} else {
Label retry_load, done;
prfm(Address(addr), PSTL1STRM);
bind(retry_load);
load_exclusive(result, addr, size, acquire);
compare_eq(result, expected, size);
br(Assembler::NE, done);
store_exclusive(rscratch1, new_val, addr, size, release);
if (weak) {
cmpw(rscratch1, 0u); // If the store fails, return NE to our caller.
} else {
cbnzw(rscratch1, retry_load);
}
bind(done);
}
BLOCK_COMMENT("} cmpxchg");
}
// A generic comparison. Only compares for equality, clobbers rscratch1.
void MacroAssembler::compare_eq(Register rm, Register rn, enum operand_size size) {
if (size == xword) {
cmp(rm, rn);
} else if (size == word) {
cmpw(rm, rn);
} else if (size == halfword) {
eorw(rscratch1, rm, rn);
ands(zr, rscratch1, 0xffff);
} else if (size == byte) {
eorw(rscratch1, rm, rn);
ands(zr, rscratch1, 0xff);
} else {
ShouldNotReachHere();
}
}
static bool different(Register a, RegisterOrConstant b, Register c) {
if (b.is_constant())
return a != c;
else
return a != b.as_register() && a != c && b.as_register() != c;
}
#define ATOMIC_OP(NAME, LDXR, OP, IOP, AOP, STXR, sz) \
void MacroAssembler::atomic_##NAME(Register prev, RegisterOrConstant incr, Register addr) { \
if (UseLSE) { \
prev = prev->is_valid() ? prev : zr; \
if (incr.is_register()) { \
AOP(sz, incr.as_register(), prev, addr); \
} else { \
mov(rscratch2, incr.as_constant()); \
AOP(sz, rscratch2, prev, addr); \
} \
return; \
} \
Register result = rscratch2; \
if (prev->is_valid()) \
result = different(prev, incr, addr) ? prev : rscratch2; \
\
Label retry_load; \
prfm(Address(addr), PSTL1STRM); \
bind(retry_load); \
LDXR(result, addr); \
OP(rscratch1, result, incr); \
STXR(rscratch2, rscratch1, addr); \
cbnzw(rscratch2, retry_load); \
if (prev->is_valid() && prev != result) { \
IOP(prev, rscratch1, incr); \
} \
}
ATOMIC_OP(add, ldxr, add, sub, ldadd, stxr, Assembler::xword)
ATOMIC_OP(addw, ldxrw, addw, subw, ldadd, stxrw, Assembler::word)
ATOMIC_OP(addal, ldaxr, add, sub, ldaddal, stlxr, Assembler::xword)
ATOMIC_OP(addalw, ldaxrw, addw, subw, ldaddal, stlxrw, Assembler::word)
#undef ATOMIC_OP
#define ATOMIC_XCHG(OP, AOP, LDXR, STXR, sz) \
void MacroAssembler::atomic_##OP(Register prev, Register newv, Register addr) { \
if (UseLSE) { \
prev = prev->is_valid() ? prev : zr; \
AOP(sz, newv, prev, addr); \
return; \
} \
Register result = rscratch2; \
if (prev->is_valid()) \
result = different(prev, newv, addr) ? prev : rscratch2; \
\
Label retry_load; \
prfm(Address(addr), PSTL1STRM); \
bind(retry_load); \
LDXR(result, addr); \
STXR(rscratch1, newv, addr); \
cbnzw(rscratch1, retry_load); \
if (prev->is_valid() && prev != result) \
mov(prev, result); \
}
ATOMIC_XCHG(xchg, swp, ldxr, stxr, Assembler::xword)
ATOMIC_XCHG(xchgw, swp, ldxrw, stxrw, Assembler::word)
ATOMIC_XCHG(xchgl, swpl, ldxr, stlxr, Assembler::xword)
ATOMIC_XCHG(xchglw, swpl, ldxrw, stlxrw, Assembler::word)
ATOMIC_XCHG(xchgal, swpal, ldaxr, stlxr, Assembler::xword)
ATOMIC_XCHG(xchgalw, swpal, ldaxrw, stlxrw, Assembler::word)
#undef ATOMIC_XCHG
#ifndef PRODUCT
extern "C" void findpc(intptr_t x);
#endif
void MacroAssembler::debug64(char* msg, int64_t pc, int64_t regs[])
{
// In order to get locks to work, we need to fake a in_VM state
if (ShowMessageBoxOnError ) {
JavaThread* thread = JavaThread::current();
JavaThreadState saved_state = thread->thread_state();
thread->set_thread_state(_thread_in_vm);
#ifndef PRODUCT
if (CountBytecodes || TraceBytecodes || StopInterpreterAt) {
ttyLocker ttyl;
BytecodeCounter::print();
}
#endif
if (os::message_box(msg, "Execution stopped, print registers?")) {
ttyLocker ttyl;
tty->print_cr(" pc = 0x%016" PRIx64, pc);
#ifndef PRODUCT
tty->cr();
findpc(pc);
tty->cr();
#endif
tty->print_cr(" r0 = 0x%016" PRIx64, regs[0]);
tty->print_cr(" r1 = 0x%016" PRIx64, regs[1]);
tty->print_cr(" r2 = 0x%016" PRIx64, regs[2]);
tty->print_cr(" r3 = 0x%016" PRIx64, regs[3]);
tty->print_cr(" r4 = 0x%016" PRIx64, regs[4]);
tty->print_cr(" r5 = 0x%016" PRIx64, regs[5]);
tty->print_cr(" r6 = 0x%016" PRIx64, regs[6]);
tty->print_cr(" r7 = 0x%016" PRIx64, regs[7]);
tty->print_cr(" r8 = 0x%016" PRIx64, regs[8]);
tty->print_cr(" r9 = 0x%016" PRIx64, regs[9]);
tty->print_cr("r10 = 0x%016" PRIx64, regs[10]);
tty->print_cr("r11 = 0x%016" PRIx64, regs[11]);
tty->print_cr("r12 = 0x%016" PRIx64, regs[12]);
tty->print_cr("r13 = 0x%016" PRIx64, regs[13]);
tty->print_cr("r14 = 0x%016" PRIx64, regs[14]);
tty->print_cr("r15 = 0x%016" PRIx64, regs[15]);
tty->print_cr("r16 = 0x%016" PRIx64, regs[16]);
tty->print_cr("r17 = 0x%016" PRIx64, regs[17]);
tty->print_cr("r18 = 0x%016" PRIx64, regs[18]);
tty->print_cr("r19 = 0x%016" PRIx64, regs[19]);
tty->print_cr("r20 = 0x%016" PRIx64, regs[20]);
tty->print_cr("r21 = 0x%016" PRIx64, regs[21]);
tty->print_cr("r22 = 0x%016" PRIx64, regs[22]);
tty->print_cr("r23 = 0x%016" PRIx64, regs[23]);
tty->print_cr("r24 = 0x%016" PRIx64, regs[24]);
tty->print_cr("r25 = 0x%016" PRIx64, regs[25]);
tty->print_cr("r26 = 0x%016" PRIx64, regs[26]);
tty->print_cr("r27 = 0x%016" PRIx64, regs[27]);
tty->print_cr("r28 = 0x%016" PRIx64, regs[28]);
tty->print_cr("r30 = 0x%016" PRIx64, regs[30]);
tty->print_cr("r31 = 0x%016" PRIx64, regs[31]);
BREAKPOINT;
}
}
fatal("DEBUG MESSAGE: %s", msg);
}
RegSet MacroAssembler::call_clobbered_gp_registers() {
RegSet regs = RegSet::range(r0, r17) - RegSet::of(rscratch1, rscratch2);
#ifndef R18_RESERVED
regs += r18_tls;
#endif
return regs;
}
void MacroAssembler::push_call_clobbered_registers_except(RegSet exclude) {
int step = 4 * wordSize;
push(call_clobbered_gp_registers() - exclude, sp);
sub(sp, sp, step);
mov(rscratch1, -step);
// Push v0-v7, v16-v31.
for (int i = 31; i>= 4; i -= 4) {
if (i <= v7->encoding() || i >= v16->encoding())
st1(as_FloatRegister(i-3), as_FloatRegister(i-2), as_FloatRegister(i-1),
as_FloatRegister(i), T1D, Address(post(sp, rscratch1)));
}
st1(as_FloatRegister(0), as_FloatRegister(1), as_FloatRegister(2),
as_FloatRegister(3), T1D, Address(sp));
}
void MacroAssembler::pop_call_clobbered_registers_except(RegSet exclude) {
for (int i = 0; i < 32; i += 4) {
if (i <= v7->encoding() || i >= v16->encoding())
ld1(as_FloatRegister(i), as_FloatRegister(i+1), as_FloatRegister(i+2),
as_FloatRegister(i+3), T1D, Address(post(sp, 4 * wordSize)));
}
reinitialize_ptrue();
pop(call_clobbered_gp_registers() - exclude, sp);
}
void MacroAssembler::push_CPU_state(bool save_vectors, bool use_sve,
int sve_vector_size_in_bytes, int total_predicate_in_bytes) {
push(RegSet::range(r0, r29), sp); // integer registers except lr & sp
if (save_vectors && use_sve && sve_vector_size_in_bytes > 16) {
sub(sp, sp, sve_vector_size_in_bytes * FloatRegister::number_of_registers);
for (int i = 0; i < FloatRegister::number_of_registers; i++) {
sve_str(as_FloatRegister(i), Address(sp, i));
}
} else {
int step = (save_vectors ? 8 : 4) * wordSize;
mov(rscratch1, -step);
sub(sp, sp, step);
for (int i = 28; i >= 4; i -= 4) {
st1(as_FloatRegister(i), as_FloatRegister(i+1), as_FloatRegister(i+2),
as_FloatRegister(i+3), save_vectors ? T2D : T1D, Address(post(sp, rscratch1)));
}
st1(v0, v1, v2, v3, save_vectors ? T2D : T1D, sp);
}
if (save_vectors && use_sve && total_predicate_in_bytes > 0) {
sub(sp, sp, total_predicate_in_bytes);
for (int i = 0; i < PRegister::number_of_registers; i++) {
sve_str(as_PRegister(i), Address(sp, i));
}
}
}
void MacroAssembler::pop_CPU_state(bool restore_vectors, bool use_sve,
int sve_vector_size_in_bytes, int total_predicate_in_bytes) {
if (restore_vectors && use_sve && total_predicate_in_bytes > 0) {
for (int i = PRegister::number_of_registers - 1; i >= 0; i--) {
sve_ldr(as_PRegister(i), Address(sp, i));
}
add(sp, sp, total_predicate_in_bytes);
}
if (restore_vectors && use_sve && sve_vector_size_in_bytes > 16) {
for (int i = FloatRegister::number_of_registers - 1; i >= 0; i--) {
sve_ldr(as_FloatRegister(i), Address(sp, i));
}
add(sp, sp, sve_vector_size_in_bytes * FloatRegister::number_of_registers);
} else {
int step = (restore_vectors ? 8 : 4) * wordSize;
for (int i = 0; i <= 28; i += 4)
ld1(as_FloatRegister(i), as_FloatRegister(i+1), as_FloatRegister(i+2),
as_FloatRegister(i+3), restore_vectors ? T2D : T1D, Address(post(sp, step)));
}
// We may use predicate registers and rely on ptrue with SVE,
// regardless of wide vector (> 8 bytes) used or not.
if (use_sve) {
reinitialize_ptrue();
}
// integer registers except lr & sp
pop(RegSet::range(r0, r17), sp);
#ifdef R18_RESERVED
ldp(zr, r19, Address(post(sp, 2 * wordSize)));
pop(RegSet::range(r20, r29), sp);
#else
pop(RegSet::range(r18_tls, r29), sp);
#endif
}
/**
* Helpers for multiply_to_len().
*/
void MacroAssembler::add2_with_carry(Register final_dest_hi, Register dest_hi, Register dest_lo,
Register src1, Register src2) {
adds(dest_lo, dest_lo, src1);
adc(dest_hi, dest_hi, zr);
adds(dest_lo, dest_lo, src2);
adc(final_dest_hi, dest_hi, zr);
}
// Generate an address from (r + r1 extend offset). "size" is the
// size of the operand. The result may be in rscratch2.
Address MacroAssembler::offsetted_address(Register r, Register r1,
Address::extend ext, int offset, int size) {
if (offset || (ext.shift() % size != 0)) {
lea(rscratch2, Address(r, r1, ext));
return Address(rscratch2, offset);
} else {
return Address(r, r1, ext);
}
}
Address MacroAssembler::spill_address(int size, int offset, Register tmp)
{
assert(offset >= 0, "spill to negative address?");
// Offset reachable ?
// Not aligned - 9 bits signed offset
// Aligned - 12 bits unsigned offset shifted
Register base = sp;
if ((offset & (size-1)) && offset >= (1<<8)) {
add(tmp, base, offset & ((1<<12)-1));
base = tmp;
offset &= -1u<<12;
}
if (offset >= (1<<12) * size) {
add(tmp, base, offset & (((1<<12)-1)<<12));
base = tmp;
offset &= ~(((1<<12)-1)<<12);
}
return Address(base, offset);
}
Address MacroAssembler::sve_spill_address(int sve_reg_size_in_bytes, int offset, Register tmp) {
assert(offset >= 0, "spill to negative address?");
Register base = sp;
// An immediate offset in the range 0 to 255 which is multiplied
// by the current vector or predicate register size in bytes.
if (offset % sve_reg_size_in_bytes == 0 && offset < ((1<<8)*sve_reg_size_in_bytes)) {
return Address(base, offset / sve_reg_size_in_bytes);
}
add(tmp, base, offset);
return Address(tmp);
}
// Checks whether offset is aligned.
// Returns true if it is, else false.
bool MacroAssembler::merge_alignment_check(Register base,
size_t size,
int64_t cur_offset,
int64_t prev_offset) const {
if (AvoidUnalignedAccesses) {
if (base == sp) {
// Checks whether low offset if aligned to pair of registers.
int64_t pair_mask = size * 2 - 1;
int64_t offset = prev_offset > cur_offset ? cur_offset : prev_offset;
return (offset & pair_mask) == 0;
} else { // If base is not sp, we can't guarantee the access is aligned.
return false;
}
} else {
int64_t mask = size - 1;
// Load/store pair instruction only supports element size aligned offset.
return (cur_offset & mask) == 0 && (prev_offset & mask) == 0;
}
}
// Checks whether current and previous loads/stores can be merged.
// Returns true if it can be merged, else false.
bool MacroAssembler::ldst_can_merge(Register rt,
const Address &adr,
size_t cur_size_in_bytes,
bool is_store) const {
address prev = pc() - NativeInstruction::instruction_size;
address last = code()->last_insn();
if (last == nullptr || !nativeInstruction_at(last)->is_Imm_LdSt()) {
return false;
}
if (adr.getMode() != Address::base_plus_offset || prev != last) {
return false;
}
NativeLdSt* prev_ldst = NativeLdSt_at(prev);
size_t prev_size_in_bytes = prev_ldst->size_in_bytes();
assert(prev_size_in_bytes == 4 || prev_size_in_bytes == 8, "only supports 64/32bit merging.");
assert(cur_size_in_bytes == 4 || cur_size_in_bytes == 8, "only supports 64/32bit merging.");
if (cur_size_in_bytes != prev_size_in_bytes || is_store != prev_ldst->is_store()) {
return false;
}
int64_t max_offset = 63 * prev_size_in_bytes;
int64_t min_offset = -64 * prev_size_in_bytes;
assert(prev_ldst->is_not_pre_post_index(), "pre-index or post-index is not supported to be merged.");
// Only same base can be merged.
if (adr.base() != prev_ldst->base()) {
return false;
}
int64_t cur_offset = adr.offset();
int64_t prev_offset = prev_ldst->offset();
size_t diff = abs(cur_offset - prev_offset);
if (diff != prev_size_in_bytes) {
return false;
}
// Following cases can not be merged:
// ldr x2, [x2, #8]
// ldr x3, [x2, #16]
// or:
// ldr x2, [x3, #8]
// ldr x2, [x3, #16]
// If t1 and t2 is the same in "ldp t1, t2, [xn, #imm]", we'll get SIGILL.
if (!is_store && (adr.base() == prev_ldst->target() || rt == prev_ldst->target())) {
return false;
}
int64_t low_offset = prev_offset > cur_offset ? cur_offset : prev_offset;
// Offset range must be in ldp/stp instruction's range.
if (low_offset > max_offset || low_offset < min_offset) {
return false;
}
if (merge_alignment_check(adr.base(), prev_size_in_bytes, cur_offset, prev_offset)) {
return true;
}
return false;
}
// Merge current load/store with previous load/store into ldp/stp.
void MacroAssembler::merge_ldst(Register rt,
const Address &adr,
size_t cur_size_in_bytes,
bool is_store) {
assert(ldst_can_merge(rt, adr, cur_size_in_bytes, is_store) == true, "cur and prev must be able to be merged.");
Register rt_low, rt_high;
address prev = pc() - NativeInstruction::instruction_size;
NativeLdSt* prev_ldst = NativeLdSt_at(prev);
int64_t offset;
if (adr.offset() < prev_ldst->offset()) {
offset = adr.offset();
rt_low = rt;
rt_high = prev_ldst->target();
} else {
offset = prev_ldst->offset();
rt_low = prev_ldst->target();
rt_high = rt;
}
Address adr_p = Address(prev_ldst->base(), offset);
// Overwrite previous generated binary.
code_section()->set_end(prev);
const size_t sz = prev_ldst->size_in_bytes();
assert(sz == 8 || sz == 4, "only supports 64/32bit merging.");
if (!is_store) {
BLOCK_COMMENT("merged ldr pair");
if (sz == 8) {
ldp(rt_low, rt_high, adr_p);
} else {
ldpw(rt_low, rt_high, adr_p);
}
} else {
BLOCK_COMMENT("merged str pair");
if (sz == 8) {
stp(rt_low, rt_high, adr_p);
} else {
stpw(rt_low, rt_high, adr_p);
}
}
}
/**
* Multiply 64 bit by 64 bit first loop.
*/
void MacroAssembler::multiply_64_x_64_loop(Register x, Register xstart, Register x_xstart,
Register y, Register y_idx, Register z,
Register carry, Register product,
Register idx, Register kdx) {
//
// jlong carry, x[], y[], z[];
// for (int idx=ystart, kdx=ystart+1+xstart; idx >= 0; idx-, kdx--) {
// huge_128 product = y[idx] * x[xstart] + carry;
// z[kdx] = (jlong)product;
// carry = (jlong)(product >>> 64);
// }
// z[xstart] = carry;
//
Label L_first_loop, L_first_loop_exit;
Label L_one_x, L_one_y, L_multiply;
subsw(xstart, xstart, 1);
br(Assembler::MI, L_one_x);
lea(rscratch1, Address(x, xstart, Address::lsl(LogBytesPerInt)));
ldr(x_xstart, Address(rscratch1));
ror(x_xstart, x_xstart, 32); // convert big-endian to little-endian
bind(L_first_loop);
subsw(idx, idx, 1);
br(Assembler::MI, L_first_loop_exit);
subsw(idx, idx, 1);
br(Assembler::MI, L_one_y);
lea(rscratch1, Address(y, idx, Address::uxtw(LogBytesPerInt)));
ldr(y_idx, Address(rscratch1));
ror(y_idx, y_idx, 32); // convert big-endian to little-endian
bind(L_multiply);
// AArch64 has a multiply-accumulate instruction that we can't use
// here because it has no way to process carries, so we have to use
// separate add and adc instructions. Bah.
umulh(rscratch1, x_xstart, y_idx); // x_xstart * y_idx -> rscratch1:product
mul(product, x_xstart, y_idx);
adds(product, product, carry);
adc(carry, rscratch1, zr); // x_xstart * y_idx + carry -> carry:product
subw(kdx, kdx, 2);
ror(product, product, 32); // back to big-endian
str(product, offsetted_address(z, kdx, Address::uxtw(LogBytesPerInt), 0, BytesPerLong));
b(L_first_loop);
bind(L_one_y);
ldrw(y_idx, Address(y, 0));
b(L_multiply);
bind(L_one_x);
ldrw(x_xstart, Address(x, 0));
b(L_first_loop);
bind(L_first_loop_exit);
}
/**
* Multiply 128 bit by 128. Unrolled inner loop.
*
*/
void MacroAssembler::multiply_128_x_128_loop(Register y, Register z,
Register carry, Register carry2,
Register idx, Register jdx,
Register yz_idx1, Register yz_idx2,
Register tmp, Register tmp3, Register tmp4,
Register tmp6, Register product_hi) {
// jlong carry, x[], y[], z[];
// int kdx = ystart+1;
// for (int idx=ystart-2; idx >= 0; idx -= 2) { // Third loop
// huge_128 tmp3 = (y[idx+1] * product_hi) + z[kdx+idx+1] + carry;
// jlong carry2 = (jlong)(tmp3 >>> 64);
// huge_128 tmp4 = (y[idx] * product_hi) + z[kdx+idx] + carry2;
// carry = (jlong)(tmp4 >>> 64);
// z[kdx+idx+1] = (jlong)tmp3;
// z[kdx+idx] = (jlong)tmp4;
// }
// idx += 2;
// if (idx > 0) {
// yz_idx1 = (y[idx] * product_hi) + z[kdx+idx] + carry;
// z[kdx+idx] = (jlong)yz_idx1;
// carry = (jlong)(yz_idx1 >>> 64);
// }
//
Label L_third_loop, L_third_loop_exit, L_post_third_loop_done;
lsrw(jdx, idx, 2);
bind(L_third_loop);
subsw(jdx, jdx, 1);
br(Assembler::MI, L_third_loop_exit);
subw(idx, idx, 4);
lea(rscratch1, Address(y, idx, Address::uxtw(LogBytesPerInt)));
ldp(yz_idx2, yz_idx1, Address(rscratch1, 0));
lea(tmp6, Address(z, idx, Address::uxtw(LogBytesPerInt)));
ror(yz_idx1, yz_idx1, 32); // convert big-endian to little-endian
ror(yz_idx2, yz_idx2, 32);
ldp(rscratch2, rscratch1, Address(tmp6, 0));
mul(tmp3, product_hi, yz_idx1); // yz_idx1 * product_hi -> tmp4:tmp3
umulh(tmp4, product_hi, yz_idx1);
ror(rscratch1, rscratch1, 32); // convert big-endian to little-endian
ror(rscratch2, rscratch2, 32);
mul(tmp, product_hi, yz_idx2); // yz_idx2 * product_hi -> carry2:tmp
umulh(carry2, product_hi, yz_idx2);
// propagate sum of both multiplications into carry:tmp4:tmp3
adds(tmp3, tmp3, carry);
adc(tmp4, tmp4, zr);
adds(tmp3, tmp3, rscratch1);
adcs(tmp4, tmp4, tmp);
adc(carry, carry2, zr);
adds(tmp4, tmp4, rscratch2);
adc(carry, carry, zr);
ror(tmp3, tmp3, 32); // convert little-endian to big-endian
ror(tmp4, tmp4, 32);
stp(tmp4, tmp3, Address(tmp6, 0));
b(L_third_loop);
bind (L_third_loop_exit);
andw (idx, idx, 0x3);
cbz(idx, L_post_third_loop_done);
Label L_check_1;
subsw(idx, idx, 2);
br(Assembler::MI, L_check_1);
lea(rscratch1, Address(y, idx, Address::uxtw(LogBytesPerInt)));
ldr(yz_idx1, Address(rscratch1, 0));
ror(yz_idx1, yz_idx1, 32);
mul(tmp3, product_hi, yz_idx1); // yz_idx1 * product_hi -> tmp4:tmp3
umulh(tmp4, product_hi, yz_idx1);
lea(rscratch1, Address(z, idx, Address::uxtw(LogBytesPerInt)));
ldr(yz_idx2, Address(rscratch1, 0));
ror(yz_idx2, yz_idx2, 32);
add2_with_carry(carry, tmp4, tmp3, carry, yz_idx2);
ror(tmp3, tmp3, 32);
str(tmp3, Address(rscratch1, 0));
bind (L_check_1);
andw (idx, idx, 0x1);
subsw(idx, idx, 1);
br(Assembler::MI, L_post_third_loop_done);
ldrw(tmp4, Address(y, idx, Address::uxtw(LogBytesPerInt)));
mul(tmp3, tmp4, product_hi); // tmp4 * product_hi -> carry2:tmp3
umulh(carry2, tmp4, product_hi);
ldrw(tmp4, Address(z, idx, Address::uxtw(LogBytesPerInt)));
add2_with_carry(carry2, tmp3, tmp4, carry);
strw(tmp3, Address(z, idx, Address::uxtw(LogBytesPerInt)));
extr(carry, carry2, tmp3, 32);
bind(L_post_third_loop_done);
}
/**
* Code for BigInteger::multiplyToLen() intrinsic.
*
* r0: x
* r1: xlen
* r2: y
* r3: ylen
* r4: z
* r5: tmp0
* r10: tmp1
* r11: tmp2
* r12: tmp3
* r13: tmp4
* r14: tmp5
* r15: tmp6
* r16: tmp7
*
*/
void MacroAssembler::multiply_to_len(Register x, Register xlen, Register y, Register ylen,
Register z, Register tmp0,
Register tmp1, Register tmp2, Register tmp3, Register tmp4,
Register tmp5, Register tmp6, Register product_hi) {
assert_different_registers(x, xlen, y, ylen, z, tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, product_hi);
const Register idx = tmp1;
const Register kdx = tmp2;
const Register xstart = tmp3;
const Register y_idx = tmp4;
const Register carry = tmp5;
const Register product = xlen;
const Register x_xstart = tmp0;
// First Loop.
//
// final static long LONG_MASK = 0xffffffffL;
// int xstart = xlen - 1;
// int ystart = ylen - 1;
// long carry = 0;
// for (int idx=ystart, kdx=ystart+1+xstart; idx >= 0; idx-, kdx--) {
// long product = (y[idx] & LONG_MASK) * (x[xstart] & LONG_MASK) + carry;
// z[kdx] = (int)product;
// carry = product >>> 32;
// }
// z[xstart] = (int)carry;
//
movw(idx, ylen); // idx = ylen;
addw(kdx, xlen, ylen); // kdx = xlen+ylen;
mov(carry, zr); // carry = 0;
Label L_done;
movw(xstart, xlen);
subsw(xstart, xstart, 1);
br(Assembler::MI, L_done);
multiply_64_x_64_loop(x, xstart, x_xstart, y, y_idx, z, carry, product, idx, kdx);
Label L_second_loop;
cbzw(kdx, L_second_loop);
Label L_carry;
subw(kdx, kdx, 1);
cbzw(kdx, L_carry);
strw(carry, Address(z, kdx, Address::uxtw(LogBytesPerInt)));
lsr(carry, carry, 32);
subw(kdx, kdx, 1);
bind(L_carry);
strw(carry, Address(z, kdx, Address::uxtw(LogBytesPerInt)));
// Second and third (nested) loops.
//
// for (int i = xstart-1; i >= 0; i--) { // Second loop
// carry = 0;
// for (int jdx=ystart, k=ystart+1+i; jdx >= 0; jdx--, k--) { // Third loop
// long product = (y[jdx] & LONG_MASK) * (x[i] & LONG_MASK) +
// (z[k] & LONG_MASK) + carry;
// z[k] = (int)product;
// carry = product >>> 32;
// }
// z[i] = (int)carry;
// }
//
// i = xlen, j = tmp1, k = tmp2, carry = tmp5, x[i] = product_hi
const Register jdx = tmp1;
bind(L_second_loop);
mov(carry, zr); // carry = 0;
movw(jdx, ylen); // j = ystart+1
subsw(xstart, xstart, 1); // i = xstart-1;
br(Assembler::MI, L_done);
str(z, Address(pre(sp, -4 * wordSize)));
Label L_last_x;
lea(z, offsetted_address(z, xstart, Address::uxtw(LogBytesPerInt), 4, BytesPerInt)); // z = z + k - j
subsw(xstart, xstart, 1); // i = xstart-1;
br(Assembler::MI, L_last_x);
lea(rscratch1, Address(x, xstart, Address::uxtw(LogBytesPerInt)));
ldr(product_hi, Address(rscratch1));
ror(product_hi, product_hi, 32); // convert big-endian to little-endian
Label L_third_loop_prologue;
bind(L_third_loop_prologue);
str(ylen, Address(sp, wordSize));
stp(x, xstart, Address(sp, 2 * wordSize));
multiply_128_x_128_loop(y, z, carry, x, jdx, ylen, product,
tmp2, x_xstart, tmp3, tmp4, tmp6, product_hi);
ldp(z, ylen, Address(post(sp, 2 * wordSize)));
ldp(x, xlen, Address(post(sp, 2 * wordSize))); // copy old xstart -> xlen
addw(tmp3, xlen, 1);
strw(carry, Address(z, tmp3, Address::uxtw(LogBytesPerInt)));
subsw(tmp3, tmp3, 1);
br(Assembler::MI, L_done);
lsr(carry, carry, 32);
strw(carry, Address(z, tmp3, Address::uxtw(LogBytesPerInt)));
b(L_second_loop);
// Next infrequent code is moved outside loops.
bind(L_last_x);
ldrw(product_hi, Address(x, 0));
b(L_third_loop_prologue);
bind(L_done);
}
// Code for BigInteger::mulAdd intrinsic
// out = r0
// in = r1
// offset = r2 (already out.length-offset)
// len = r3
// k = r4
//
// pseudo code from java implementation:
// carry = 0;
// offset = out.length-offset - 1;
// for (int j=len-1; j >= 0; j--) {
// product = (in[j] & LONG_MASK) * kLong + (out[offset] & LONG_MASK) + carry;
// out[offset--] = (int)product;
// carry = product >>> 32;
// }
// return (int)carry;
void MacroAssembler::mul_add(Register out, Register in, Register offset,
Register len, Register k) {
Label LOOP, END;
// pre-loop
cmp(len, zr); // cmp, not cbz/cbnz: to use condition twice => less branches
csel(out, zr, out, Assembler::EQ);
br(Assembler::EQ, END);
add(in, in, len, LSL, 2); // in[j+1] address
add(offset, out, offset, LSL, 2); // out[offset + 1] address
mov(out, zr); // used to keep carry now
BIND(LOOP);
ldrw(rscratch1, Address(pre(in, -4)));
madd(rscratch1, rscratch1, k, out);
ldrw(rscratch2, Address(pre(offset, -4)));
add(rscratch1, rscratch1, rscratch2);
strw(rscratch1, Address(offset));
lsr(out, rscratch1, 32);
subs(len, len, 1);
br(Assembler::NE, LOOP);
BIND(END);
}
/**
* Emits code to update CRC-32 with a byte value according to constants in table
*
* @param [in,out]crc Register containing the crc.
* @param [in]val Register containing the byte to fold into the CRC.
* @param [in]table Register containing the table of crc constants.
*
* uint32_t crc;
* val = crc_table[(val ^ crc) & 0xFF];
* crc = val ^ (crc >> 8);
*
*/
void MacroAssembler::update_byte_crc32(Register crc, Register val, Register table) {
eor(val, val, crc);
andr(val, val, 0xff);
ldrw(val, Address(table, val, Address::lsl(2)));
eor(crc, val, crc, Assembler::LSR, 8);
}
/**
* Emits code to update CRC-32 with a 32-bit value according to tables 0 to 3
*
* @param [in,out]crc Register containing the crc.
* @param [in]v Register containing the 32-bit to fold into the CRC.
* @param [in]table0 Register containing table 0 of crc constants.
* @param [in]table1 Register containing table 1 of crc constants.
* @param [in]table2 Register containing table 2 of crc constants.
* @param [in]table3 Register containing table 3 of crc constants.
*
* uint32_t crc;
* v = crc ^ v
* crc = table3[v&0xff]^table2[(v>>8)&0xff]^table1[(v>>16)&0xff]^table0[v>>24]
*
*/
void MacroAssembler::update_word_crc32(Register crc, Register v, Register tmp,
Register table0, Register table1, Register table2, Register table3,
bool upper) {
eor(v, crc, v, upper ? LSR:LSL, upper ? 32:0);
uxtb(tmp, v);
ldrw(crc, Address(table3, tmp, Address::lsl(2)));
ubfx(tmp, v, 8, 8);
ldrw(tmp, Address(table2, tmp, Address::lsl(2)));
eor(crc, crc, tmp);
ubfx(tmp, v, 16, 8);
ldrw(tmp, Address(table1, tmp, Address::lsl(2)));
eor(crc, crc, tmp);
ubfx(tmp, v, 24, 8);
ldrw(tmp, Address(table0, tmp, Address::lsl(2)));
eor(crc, crc, tmp);
}
void MacroAssembler::kernel_crc32_using_crypto_pmull(Register crc, Register buf,
Register len, Register tmp0, Register tmp1, Register tmp2, Register tmp3) {
Label CRC_by4_loop, CRC_by1_loop, CRC_less128, CRC_by128_pre, CRC_by32_loop, CRC_less32, L_exit;
assert_different_registers(crc, buf, len, tmp0, tmp1, tmp2);
subs(tmp0, len, 384);
mvnw(crc, crc);
br(Assembler::GE, CRC_by128_pre);
BIND(CRC_less128);
subs(len, len, 32);
br(Assembler::GE, CRC_by32_loop);
BIND(CRC_less32);
adds(len, len, 32 - 4);
br(Assembler::GE, CRC_by4_loop);
adds(len, len, 4);
br(Assembler::GT, CRC_by1_loop);
b(L_exit);
BIND(CRC_by32_loop);
ldp(tmp0, tmp1, Address(buf));
crc32x(crc, crc, tmp0);
ldp(tmp2, tmp3, Address(buf, 16));
crc32x(crc, crc, tmp1);
add(buf, buf, 32);
crc32x(crc, crc, tmp2);
subs(len, len, 32);
crc32x(crc, crc, tmp3);
br(Assembler::GE, CRC_by32_loop);
cmn(len, (u1)32);
br(Assembler::NE, CRC_less32);
b(L_exit);
BIND(CRC_by4_loop);
ldrw(tmp0, Address(post(buf, 4)));
subs(len, len, 4);
crc32w(crc, crc, tmp0);
br(Assembler::GE, CRC_by4_loop);
adds(len, len, 4);
br(Assembler::LE, L_exit);
BIND(CRC_by1_loop);
ldrb(tmp0, Address(post(buf, 1)));
subs(len, len, 1);
crc32b(crc, crc, tmp0);
br(Assembler::GT, CRC_by1_loop);
b(L_exit);
BIND(CRC_by128_pre);
kernel_crc32_common_fold_using_crypto_pmull(crc, buf, len, tmp0, tmp1, tmp2,
4*256*sizeof(juint) + 8*sizeof(juint));
mov(crc, 0);
crc32x(crc, crc, tmp0);
crc32x(crc, crc, tmp1);
cbnz(len, CRC_less128);
BIND(L_exit);
mvnw(crc, crc);
}
void MacroAssembler::kernel_crc32_using_crc32(Register crc, Register buf,
Register len, Register tmp0, Register tmp1, Register tmp2,
Register tmp3) {
Label CRC_by64_loop, CRC_by4_loop, CRC_by1_loop, CRC_less64, CRC_by64_pre, CRC_by32_loop, CRC_less32, L_exit;
assert_different_registers(crc, buf, len, tmp0, tmp1, tmp2, tmp3);
mvnw(crc, crc);
subs(len, len, 128);
br(Assembler::GE, CRC_by64_pre);
BIND(CRC_less64);
adds(len, len, 128-32);
br(Assembler::GE, CRC_by32_loop);
BIND(CRC_less32);
adds(len, len, 32-4);
br(Assembler::GE, CRC_by4_loop);
adds(len, len, 4);
br(Assembler::GT, CRC_by1_loop);
b(L_exit);
BIND(CRC_by32_loop);
ldp(tmp0, tmp1, Address(post(buf, 16)));
subs(len, len, 32);
crc32x(crc, crc, tmp0);
ldr(tmp2, Address(post(buf, 8)));
crc32x(crc, crc, tmp1);
ldr(tmp3, Address(post(buf, 8)));
crc32x(crc, crc, tmp2);
crc32x(crc, crc, tmp3);
br(Assembler::GE, CRC_by32_loop);
cmn(len, (u1)32);
br(Assembler::NE, CRC_less32);
b(L_exit);
BIND(CRC_by4_loop);
ldrw(tmp0, Address(post(buf, 4)));
subs(len, len, 4);
crc32w(crc, crc, tmp0);
br(Assembler::GE, CRC_by4_loop);
adds(len, len, 4);
br(Assembler::LE, L_exit);
BIND(CRC_by1_loop);
ldrb(tmp0, Address(post(buf, 1)));
subs(len, len, 1);
crc32b(crc, crc, tmp0);
br(Assembler::GT, CRC_by1_loop);
b(L_exit);
BIND(CRC_by64_pre);
sub(buf, buf, 8);
ldp(tmp0, tmp1, Address(buf, 8));
crc32x(crc, crc, tmp0);
ldr(tmp2, Address(buf, 24));
crc32x(crc, crc, tmp1);
ldr(tmp3, Address(buf, 32));
crc32x(crc, crc, tmp2);
ldr(tmp0, Address(buf, 40));
crc32x(crc, crc, tmp3);
ldr(tmp1, Address(buf, 48));
crc32x(crc, crc, tmp0);
ldr(tmp2, Address(buf, 56));
crc32x(crc, crc, tmp1);
ldr(tmp3, Address(pre(buf, 64)));
b(CRC_by64_loop);
align(CodeEntryAlignment);
BIND(CRC_by64_loop);
subs(len, len, 64);
crc32x(crc, crc, tmp2);
ldr(tmp0, Address(buf, 8));
crc32x(crc, crc, tmp3);
ldr(tmp1, Address(buf, 16));
crc32x(crc, crc, tmp0);
ldr(tmp2, Address(buf, 24));
crc32x(crc, crc, tmp1);
ldr(tmp3, Address(buf, 32));
crc32x(crc, crc, tmp2);
ldr(tmp0, Address(buf, 40));
crc32x(crc, crc, tmp3);
ldr(tmp1, Address(buf, 48));
crc32x(crc, crc, tmp0);
ldr(tmp2, Address(buf, 56));
crc32x(crc, crc, tmp1);
ldr(tmp3, Address(pre(buf, 64)));
br(Assembler::GE, CRC_by64_loop);
// post-loop
crc32x(crc, crc, tmp2);
crc32x(crc, crc, tmp3);
sub(len, len, 64);
add(buf, buf, 8);
cmn(len, (u1)128);
br(Assembler::NE, CRC_less64);
BIND(L_exit);
mvnw(crc, crc);
}
/**
* @param crc register containing existing CRC (32-bit)
* @param buf register pointing to input byte buffer (byte*)
* @param len register containing number of bytes
* @param table register that will contain address of CRC table
* @param tmp scratch register
*/
void MacroAssembler::kernel_crc32(Register crc, Register buf, Register len,
Register table0, Register table1, Register table2, Register table3,
Register tmp, Register tmp2, Register tmp3) {
Label L_by16, L_by16_loop, L_by4, L_by4_loop, L_by1, L_by1_loop, L_exit;
if (UseCryptoPmullForCRC32) {
kernel_crc32_using_crypto_pmull(crc, buf, len, table0, table1, table2, table3);
return;
}
if (UseCRC32) {
kernel_crc32_using_crc32(crc, buf, len, table0, table1, table2, table3);
return;
}
mvnw(crc, crc);
{
uint64_t offset;
adrp(table0, ExternalAddress(StubRoutines::crc_table_addr()), offset);
add(table0, table0, offset);
}
add(table1, table0, 1*256*sizeof(juint));
add(table2, table0, 2*256*sizeof(juint));
add(table3, table0, 3*256*sizeof(juint));
{ // Neon code start
cmp(len, (u1)64);
br(Assembler::LT, L_by16);
eor(v16, T16B, v16, v16);
Label L_fold;
add(tmp, table0, 4*256*sizeof(juint)); // Point at the Neon constants
ld1(v0, v1, T2D, post(buf, 32));
ld1r(v4, T2D, post(tmp, 8));
ld1r(v5, T2D, post(tmp, 8));
ld1r(v6, T2D, post(tmp, 8));
ld1r(v7, T2D, post(tmp, 8));
mov(v16, S, 0, crc);
eor(v0, T16B, v0, v16);
sub(len, len, 64);
BIND(L_fold);
pmull(v22, T8H, v0, v5, T8B);
pmull(v20, T8H, v0, v7, T8B);
pmull(v23, T8H, v0, v4, T8B);
pmull(v21, T8H, v0, v6, T8B);
pmull2(v18, T8H, v0, v5, T16B);
pmull2(v16, T8H, v0, v7, T16B);
pmull2(v19, T8H, v0, v4, T16B);
pmull2(v17, T8H, v0, v6, T16B);
uzp1(v24, T8H, v20, v22);
uzp2(v25, T8H, v20, v22);
eor(v20, T16B, v24, v25);
uzp1(v26, T8H, v16, v18);
uzp2(v27, T8H, v16, v18);
eor(v16, T16B, v26, v27);
ushll2(v22, T4S, v20, T8H, 8);
ushll(v20, T4S, v20, T4H, 8);
ushll2(v18, T4S, v16, T8H, 8);
ushll(v16, T4S, v16, T4H, 8);
eor(v22, T16B, v23, v22);
eor(v18, T16B, v19, v18);
eor(v20, T16B, v21, v20);
eor(v16, T16B, v17, v16);
uzp1(v17, T2D, v16, v20);
uzp2(v21, T2D, v16, v20);
eor(v17, T16B, v17, v21);
ushll2(v20, T2D, v17, T4S, 16);
ushll(v16, T2D, v17, T2S, 16);
eor(v20, T16B, v20, v22);
eor(v16, T16B, v16, v18);
uzp1(v17, T2D, v20, v16);
uzp2(v21, T2D, v20, v16);
eor(v28, T16B, v17, v21);
pmull(v22, T8H, v1, v5, T8B);
pmull(v20, T8H, v1, v7, T8B);
pmull(v23, T8H, v1, v4, T8B);
pmull(v21, T8H, v1, v6, T8B);
pmull2(v18, T8H, v1, v5, T16B);
pmull2(v16, T8H, v1, v7, T16B);
pmull2(v19, T8H, v1, v4, T16B);
pmull2(v17, T8H, v1, v6, T16B);
ld1(v0, v1, T2D, post(buf, 32));
uzp1(v24, T8H, v20, v22);
uzp2(v25, T8H, v20, v22);
eor(v20, T16B, v24, v25);
uzp1(v26, T8H, v16, v18);
uzp2(v27, T8H, v16, v18);
eor(v16, T16B, v26, v27);
ushll2(v22, T4S, v20, T8H, 8);
ushll(v20, T4S, v20, T4H, 8);
ushll2(v18, T4S, v16, T8H, 8);
ushll(v16, T4S, v16, T4H, 8);
eor(v22, T16B, v23, v22);
eor(v18, T16B, v19, v18);
eor(v20, T16B, v21, v20);
eor(v16, T16B, v17, v16);
uzp1(v17, T2D, v16, v20);
uzp2(v21, T2D, v16, v20);
eor(v16, T16B, v17, v21);
ushll2(v20, T2D, v16, T4S, 16);
ushll(v16, T2D, v16, T2S, 16);
eor(v20, T16B, v22, v20);
eor(v16, T16B, v16, v18);
uzp1(v17, T2D, v20, v16);
uzp2(v21, T2D, v20, v16);
eor(v20, T16B, v17, v21);
shl(v16, T2D, v28, 1);
shl(v17, T2D, v20, 1);
eor(v0, T16B, v0, v16);
eor(v1, T16B, v1, v17);
subs(len, len, 32);
br(Assembler::GE, L_fold);
mov(crc, 0);
mov(tmp, v0, D, 0);
update_word_crc32(crc, tmp, tmp2, table0, table1, table2, table3, false);
update_word_crc32(crc, tmp, tmp2, table0, table1, table2, table3, true);
mov(tmp, v0, D, 1);
update_word_crc32(crc, tmp, tmp2, table0, table1, table2, table3, false);
update_word_crc32(crc, tmp, tmp2, table0, table1, table2, table3, true);
mov(tmp, v1, D, 0);
update_word_crc32(crc, tmp, tmp2, table0, table1, table2, table3, false);
update_word_crc32(crc, tmp, tmp2, table0, table1, table2, table3, true);
mov(tmp, v1, D, 1);
update_word_crc32(crc, tmp, tmp2, table0, table1, table2, table3, false);
update_word_crc32(crc, tmp, tmp2, table0, table1, table2, table3, true);
add(len, len, 32);
} // Neon code end
BIND(L_by16);
subs(len, len, 16);
br(Assembler::GE, L_by16_loop);
adds(len, len, 16-4);
br(Assembler::GE, L_by4_loop);
adds(len, len, 4);
br(Assembler::GT, L_by1_loop);
b(L_exit);
BIND(L_by4_loop);
ldrw(tmp, Address(post(buf, 4)));
update_word_crc32(crc, tmp, tmp2, table0, table1, table2, table3);
subs(len, len, 4);
br(Assembler::GE, L_by4_loop);
adds(len, len, 4);
br(Assembler::LE, L_exit);
BIND(L_by1_loop);
subs(len, len, 1);
ldrb(tmp, Address(post(buf, 1)));
update_byte_crc32(crc, tmp, table0);
br(Assembler::GT, L_by1_loop);
b(L_exit);
align(CodeEntryAlignment);
BIND(L_by16_loop);
subs(len, len, 16);
ldp(tmp, tmp3, Address(post(buf, 16)));
update_word_crc32(crc, tmp, tmp2, table0, table1, table2, table3, false);
update_word_crc32(crc, tmp, tmp2, table0, table1, table2, table3, true);
update_word_crc32(crc, tmp3, tmp2, table0, table1, table2, table3, false);
update_word_crc32(crc, tmp3, tmp2, table0, table1, table2, table3, true);
br(Assembler::GE, L_by16_loop);
adds(len, len, 16-4);
br(Assembler::GE, L_by4_loop);
adds(len, len, 4);
br(Assembler::GT, L_by1_loop);
BIND(L_exit);
mvnw(crc, crc);
}
void MacroAssembler::kernel_crc32c_using_crypto_pmull(Register crc, Register buf,
Register len, Register tmp0, Register tmp1, Register tmp2, Register tmp3) {
Label CRC_by4_loop, CRC_by1_loop, CRC_less128, CRC_by128_pre, CRC_by32_loop, CRC_less32, L_exit;
assert_different_registers(crc, buf, len, tmp0, tmp1, tmp2);
subs(tmp0, len, 384);
br(Assembler::GE, CRC_by128_pre);
BIND(CRC_less128);
subs(len, len, 32);
br(Assembler::GE, CRC_by32_loop);
BIND(CRC_less32);
adds(len, len, 32 - 4);
br(Assembler::GE, CRC_by4_loop);
adds(len, len, 4);
br(Assembler::GT, CRC_by1_loop);
b(L_exit);
BIND(CRC_by32_loop);
ldp(tmp0, tmp1, Address(buf));
crc32cx(crc, crc, tmp0);
ldr(tmp2, Address(buf, 16));
crc32cx(crc, crc, tmp1);
ldr(tmp3, Address(buf, 24));
crc32cx(crc, crc, tmp2);
add(buf, buf, 32);
subs(len, len, 32);
crc32cx(crc, crc, tmp3);
br(Assembler::GE, CRC_by32_loop);
cmn(len, (u1)32);
br(Assembler::NE, CRC_less32);
b(L_exit);
BIND(CRC_by4_loop);
ldrw(tmp0, Address(post(buf, 4)));
subs(len, len, 4);
crc32cw(crc, crc, tmp0);
br(Assembler::GE, CRC_by4_loop);
adds(len, len, 4);
br(Assembler::LE, L_exit);
BIND(CRC_by1_loop);
ldrb(tmp0, Address(post(buf, 1)));
subs(len, len, 1);
crc32cb(crc, crc, tmp0);
br(Assembler::GT, CRC_by1_loop);
b(L_exit);
BIND(CRC_by128_pre);
kernel_crc32_common_fold_using_crypto_pmull(crc, buf, len, tmp0, tmp1, tmp2,
4*256*sizeof(juint) + 8*sizeof(juint) + 0x50);
mov(crc, 0);
crc32cx(crc, crc, tmp0);
crc32cx(crc, crc, tmp1);
cbnz(len, CRC_less128);
BIND(L_exit);
}
void MacroAssembler::kernel_crc32c_using_crc32c(Register crc, Register buf,
Register len, Register tmp0, Register tmp1, Register tmp2,
Register tmp3) {
Label CRC_by64_loop, CRC_by4_loop, CRC_by1_loop, CRC_less64, CRC_by64_pre, CRC_by32_loop, CRC_less32, L_exit;
assert_different_registers(crc, buf, len, tmp0, tmp1, tmp2, tmp3);
subs(len, len, 128);
br(Assembler::GE, CRC_by64_pre);
BIND(CRC_less64);
adds(len, len, 128-32);
br(Assembler::GE, CRC_by32_loop);
BIND(CRC_less32);
adds(len, len, 32-4);
br(Assembler::GE, CRC_by4_loop);
adds(len, len, 4);
br(Assembler::GT, CRC_by1_loop);
b(L_exit);
BIND(CRC_by32_loop);
ldp(tmp0, tmp1, Address(post(buf, 16)));
subs(len, len, 32);
crc32cx(crc, crc, tmp0);
ldr(tmp2, Address(post(buf, 8)));
crc32cx(crc, crc, tmp1);
ldr(tmp3, Address(post(buf, 8)));
crc32cx(crc, crc, tmp2);
crc32cx(crc, crc, tmp3);
br(Assembler::GE, CRC_by32_loop);
cmn(len, (u1)32);
br(Assembler::NE, CRC_less32);
b(L_exit);
BIND(CRC_by4_loop);
ldrw(tmp0, Address(post(buf, 4)));
subs(len, len, 4);
crc32cw(crc, crc, tmp0);
br(Assembler::GE, CRC_by4_loop);
adds(len, len, 4);
br(Assembler::LE, L_exit);
BIND(CRC_by1_loop);
ldrb(tmp0, Address(post(buf, 1)));
subs(len, len, 1);
crc32cb(crc, crc, tmp0);
br(Assembler::GT, CRC_by1_loop);
b(L_exit);
BIND(CRC_by64_pre);
sub(buf, buf, 8);
ldp(tmp0, tmp1, Address(buf, 8));
crc32cx(crc, crc, tmp0);
ldr(tmp2, Address(buf, 24));
crc32cx(crc, crc, tmp1);
ldr(tmp3, Address(buf, 32));
crc32cx(crc, crc, tmp2);
ldr(tmp0, Address(buf, 40));
crc32cx(crc, crc, tmp3);
ldr(tmp1, Address(buf, 48));
crc32cx(crc, crc, tmp0);
ldr(tmp2, Address(buf, 56));
crc32cx(crc, crc, tmp1);
ldr(tmp3, Address(pre(buf, 64)));
b(CRC_by64_loop);
align(CodeEntryAlignment);
BIND(CRC_by64_loop);
subs(len, len, 64);
crc32cx(crc, crc, tmp2);
ldr(tmp0, Address(buf, 8));
crc32cx(crc, crc, tmp3);
ldr(tmp1, Address(buf, 16));
crc32cx(crc, crc, tmp0);
ldr(tmp2, Address(buf, 24));
crc32cx(crc, crc, tmp1);
ldr(tmp3, Address(buf, 32));
crc32cx(crc, crc, tmp2);
ldr(tmp0, Address(buf, 40));
crc32cx(crc, crc, tmp3);
ldr(tmp1, Address(buf, 48));
crc32cx(crc, crc, tmp0);
ldr(tmp2, Address(buf, 56));
crc32cx(crc, crc, tmp1);
ldr(tmp3, Address(pre(buf, 64)));
br(Assembler::GE, CRC_by64_loop);
// post-loop
crc32cx(crc, crc, tmp2);
crc32cx(crc, crc, tmp3);
sub(len, len, 64);
add(buf, buf, 8);
cmn(len, (u1)128);
br(Assembler::NE, CRC_less64);
BIND(L_exit);
}
/**
* @param crc register containing existing CRC (32-bit)
* @param buf register pointing to input byte buffer (byte*)
* @param len register containing number of bytes
* @param table register that will contain address of CRC table
* @param tmp scratch register
*/
void MacroAssembler::kernel_crc32c(Register crc, Register buf, Register len,
Register table0, Register table1, Register table2, Register table3,
Register tmp, Register tmp2, Register tmp3) {
if (UseCryptoPmullForCRC32) {
kernel_crc32c_using_crypto_pmull(crc, buf, len, table0, table1, table2, table3);
} else {
kernel_crc32c_using_crc32c(crc, buf, len, table0, table1, table2, table3);
}
}
void MacroAssembler::kernel_crc32_common_fold_using_crypto_pmull(Register crc, Register buf,
Register len, Register tmp0, Register tmp1, Register tmp2, size_t table_offset) {
Label CRC_by128_loop;
assert_different_registers(crc, buf, len, tmp0, tmp1, tmp2);
sub(len, len, 256);
Register table = tmp0;
{
uint64_t offset;
adrp(table, ExternalAddress(StubRoutines::crc_table_addr()), offset);
add(table, table, offset);
}
add(table, table, table_offset);
// Registers v0..v7 are used as data registers.
// Registers v16..v31 are used as tmp registers.
sub(buf, buf, 0x10);
ldrq(v0, Address(buf, 0x10));
ldrq(v1, Address(buf, 0x20));
ldrq(v2, Address(buf, 0x30));
ldrq(v3, Address(buf, 0x40));
ldrq(v4, Address(buf, 0x50));
ldrq(v5, Address(buf, 0x60));
ldrq(v6, Address(buf, 0x70));
ldrq(v7, Address(pre(buf, 0x80)));
movi(v31, T4S, 0);
mov(v31, S, 0, crc);
eor(v0, T16B, v0, v31);
// Register v16 contains constants from the crc table.
ldrq(v16, Address(table));
b(CRC_by128_loop);
align(OptoLoopAlignment);
BIND(CRC_by128_loop);
pmull (v17, T1Q, v0, v16, T1D);
pmull2(v18, T1Q, v0, v16, T2D);
ldrq(v0, Address(buf, 0x10));
eor3(v0, T16B, v17, v18, v0);
pmull (v19, T1Q, v1, v16, T1D);
pmull2(v20, T1Q, v1, v16, T2D);
ldrq(v1, Address(buf, 0x20));
eor3(v1, T16B, v19, v20, v1);
pmull (v21, T1Q, v2, v16, T1D);
pmull2(v22, T1Q, v2, v16, T2D);
ldrq(v2, Address(buf, 0x30));
eor3(v2, T16B, v21, v22, v2);
pmull (v23, T1Q, v3, v16, T1D);
pmull2(v24, T1Q, v3, v16, T2D);
ldrq(v3, Address(buf, 0x40));
eor3(v3, T16B, v23, v24, v3);
pmull (v25, T1Q, v4, v16, T1D);
pmull2(v26, T1Q, v4, v16, T2D);
ldrq(v4, Address(buf, 0x50));
eor3(v4, T16B, v25, v26, v4);
pmull (v27, T1Q, v5, v16, T1D);
pmull2(v28, T1Q, v5, v16, T2D);
ldrq(v5, Address(buf, 0x60));
eor3(v5, T16B, v27, v28, v5);
pmull (v29, T1Q, v6, v16, T1D);
pmull2(v30, T1Q, v6, v16, T2D);
ldrq(v6, Address(buf, 0x70));
eor3(v6, T16B, v29, v30, v6);
// Reuse registers v23, v24.
// Using them won't block the first instruction of the next iteration.
pmull (v23, T1Q, v7, v16, T1D);
pmull2(v24, T1Q, v7, v16, T2D);
ldrq(v7, Address(pre(buf, 0x80)));
eor3(v7, T16B, v23, v24, v7);
subs(len, len, 0x80);
br(Assembler::GE, CRC_by128_loop);
// fold into 512 bits
// Use v31 for constants because v16 can be still in use.
ldrq(v31, Address(table, 0x10));
pmull (v17, T1Q, v0, v31, T1D);
pmull2(v18, T1Q, v0, v31, T2D);
eor3(v0, T16B, v17, v18, v4);
pmull (v19, T1Q, v1, v31, T1D);
pmull2(v20, T1Q, v1, v31, T2D);
eor3(v1, T16B, v19, v20, v5);
pmull (v21, T1Q, v2, v31, T1D);
pmull2(v22, T1Q, v2, v31, T2D);
eor3(v2, T16B, v21, v22, v6);
pmull (v23, T1Q, v3, v31, T1D);
pmull2(v24, T1Q, v3, v31, T2D);
eor3(v3, T16B, v23, v24, v7);
// fold into 128 bits
// Use v17 for constants because v31 can be still in use.
ldrq(v17, Address(table, 0x20));
pmull (v25, T1Q, v0, v17, T1D);
pmull2(v26, T1Q, v0, v17, T2D);
eor3(v3, T16B, v3, v25, v26);
// Use v18 for constants because v17 can be still in use.
ldrq(v18, Address(table, 0x30));
pmull (v27, T1Q, v1, v18, T1D);
pmull2(v28, T1Q, v1, v18, T2D);
eor3(v3, T16B, v3, v27, v28);
// Use v19 for constants because v18 can be still in use.
ldrq(v19, Address(table, 0x40));
pmull (v29, T1Q, v2, v19, T1D);
pmull2(v30, T1Q, v2, v19, T2D);
eor3(v0, T16B, v3, v29, v30);
add(len, len, 0x80);
add(buf, buf, 0x10);
mov(tmp0, v0, D, 0);
mov(tmp1, v0, D, 1);
}
void MacroAssembler::addptr(const Address &dst, int32_t src) {
Address adr;
switch(dst.getMode()) {
case Address::base_plus_offset:
// This is the expected mode, although we allow all the other
// forms below.
adr = form_address(rscratch2, dst.base(), dst.offset(), LogBytesPerWord);
break;
default:
lea(rscratch2, dst);
adr = Address(rscratch2);
break;
}
ldr(rscratch1, adr);
add(rscratch1, rscratch1, src);
str(rscratch1, adr);
}
void MacroAssembler::cmpptr(Register src1, Address src2) {
uint64_t offset;
adrp(rscratch1, src2, offset);
ldr(rscratch1, Address(rscratch1, offset));
cmp(src1, rscratch1);
}
void MacroAssembler::cmpoop(Register obj1, Register obj2) {
cmp(obj1, obj2);
}
void MacroAssembler::load_method_holder_cld(Register rresult, Register rmethod) {
load_method_holder(rresult, rmethod);
ldr(rresult, Address(rresult, InstanceKlass::class_loader_data_offset()));
}
void MacroAssembler::load_method_holder(Register holder, Register method) {
ldr(holder, Address(method, Method::const_offset())); // ConstMethod*
ldr(holder, Address(holder, ConstMethod::constants_offset())); // ConstantPool*
ldr(holder, Address(holder, ConstantPool::pool_holder_offset())); // InstanceKlass*
}
// Loads the obj's Klass* into dst.
// Preserves all registers (incl src, rscratch1 and rscratch2).
// Input:
// src - the oop we want to load the klass from.
// dst - output narrow klass.
void MacroAssembler::load_narrow_klass_compact(Register dst, Register src) {
assert(UseCompactObjectHeaders, "expects UseCompactObjectHeaders");
ldr(dst, Address(src, oopDesc::mark_offset_in_bytes()));
lsr(dst, dst, markWord::klass_shift);
}
void MacroAssembler::load_klass(Register dst, Register src) {
if (UseCompactObjectHeaders) {
load_narrow_klass_compact(dst, src);
decode_klass_not_null(dst);
} else if (UseCompressedClassPointers) {
ldrw(dst, Address(src, oopDesc::klass_offset_in_bytes()));
decode_klass_not_null(dst);
} else {
ldr(dst, Address(src, oopDesc::klass_offset_in_bytes()));
}
}
void MacroAssembler::restore_cpu_control_state_after_jni(Register tmp1, Register tmp2) {
if (RestoreMXCSROnJNICalls) {
Label OK;
get_fpcr(tmp1);
mov(tmp2, tmp1);
// Set FPCR to the state we need. We do want Round to Nearest. We
// don't want non-IEEE rounding modes or floating-point traps.
bfi(tmp1, zr, 22, 4); // Clear DN, FZ, and Rmode
bfi(tmp1, zr, 8, 5); // Clear exception-control bits (8-12)
bfi(tmp1, zr, 0, 2); // Clear AH:FIZ
eor(tmp2, tmp1, tmp2);
cbz(tmp2, OK); // Only reset FPCR if it's wrong
set_fpcr(tmp1);
bind(OK);
}
}
// ((OopHandle)result).resolve();
void MacroAssembler::resolve_oop_handle(Register result, Register tmp1, Register tmp2) {
// OopHandle::resolve is an indirection.
access_load_at(T_OBJECT, IN_NATIVE, result, Address(result, 0), tmp1, tmp2);
}
// ((WeakHandle)result).resolve();
void MacroAssembler::resolve_weak_handle(Register result, Register tmp1, Register tmp2) {
assert_different_registers(result, tmp1, tmp2);
Label resolved;
// A null weak handle resolves to null.
cbz(result, resolved);
// Only 64 bit platforms support GCs that require a tmp register
// WeakHandle::resolve is an indirection like jweak.
access_load_at(T_OBJECT, IN_NATIVE | ON_PHANTOM_OOP_REF,
result, Address(result), tmp1, tmp2);
bind(resolved);
}
void MacroAssembler::load_mirror(Register dst, Register method, Register tmp1, Register tmp2) {
const int mirror_offset = in_bytes(Klass::java_mirror_offset());
ldr(dst, Address(rmethod, Method::const_offset()));
ldr(dst, Address(dst, ConstMethod::constants_offset()));
ldr(dst, Address(dst, ConstantPool::pool_holder_offset()));
ldr(dst, Address(dst, mirror_offset));
resolve_oop_handle(dst, tmp1, tmp2);
}
void MacroAssembler::cmp_klass(Register obj, Register klass, Register tmp) {
assert_different_registers(obj, klass, tmp);
if (UseCompressedClassPointers) {
if (UseCompactObjectHeaders) {
load_narrow_klass_compact(tmp, obj);
} else {
ldrw(tmp, Address(obj, oopDesc::klass_offset_in_bytes()));
}
if (CompressedKlassPointers::base() == nullptr) {
cmp(klass, tmp, LSL, CompressedKlassPointers::shift());
return;
} else if (((uint64_t)CompressedKlassPointers::base() & 0xffffffff) == 0
&& CompressedKlassPointers::shift() == 0) {
// Only the bottom 32 bits matter
cmpw(klass, tmp);
return;
}
decode_klass_not_null(tmp);
} else {
ldr(tmp, Address(obj, oopDesc::klass_offset_in_bytes()));
}
cmp(klass, tmp);
}
void MacroAssembler::cmp_klasses_from_objects(Register obj1, Register obj2, Register tmp1, Register tmp2) {
if (UseCompactObjectHeaders) {
load_narrow_klass_compact(tmp1, obj1);
load_narrow_klass_compact(tmp2, obj2);
cmpw(tmp1, tmp2);
} else if (UseCompressedClassPointers) {
ldrw(tmp1, Address(obj1, oopDesc::klass_offset_in_bytes()));
ldrw(tmp2, Address(obj2, oopDesc::klass_offset_in_bytes()));
cmpw(tmp1, tmp2);
} else {
ldr(tmp1, Address(obj1, oopDesc::klass_offset_in_bytes()));
ldr(tmp2, Address(obj2, oopDesc::klass_offset_in_bytes()));
cmp(tmp1, tmp2);
}
}
void MacroAssembler::store_klass(Register dst, Register src) {
// FIXME: Should this be a store release? concurrent gcs assumes
// klass length is valid if klass field is not null.
assert(!UseCompactObjectHeaders, "not with compact headers");
if (UseCompressedClassPointers) {
encode_klass_not_null(src);
strw(src, Address(dst, oopDesc::klass_offset_in_bytes()));
} else {
str(src, Address(dst, oopDesc::klass_offset_in_bytes()));
}
}
void MacroAssembler::store_klass_gap(Register dst, Register src) {
assert(!UseCompactObjectHeaders, "not with compact headers");
if (UseCompressedClassPointers) {
// Store to klass gap in destination
strw(src, Address(dst, oopDesc::klass_gap_offset_in_bytes()));
}
}
// Algorithm must match CompressedOops::encode.
void MacroAssembler::encode_heap_oop(Register d, Register s) {
#ifdef ASSERT
verify_heapbase("MacroAssembler::encode_heap_oop: heap base corrupted?");
#endif
verify_oop_msg(s, "broken oop in encode_heap_oop");
if (CompressedOops::base() == nullptr) {
if (CompressedOops::shift() != 0) {
assert (LogMinObjAlignmentInBytes == CompressedOops::shift(), "decode alg wrong");
lsr(d, s, LogMinObjAlignmentInBytes);
} else {
mov(d, s);
}
} else {
subs(d, s, rheapbase);
csel(d, d, zr, Assembler::HS);
lsr(d, d, LogMinObjAlignmentInBytes);
/* Old algorithm: is this any worse?
Label nonnull;
cbnz(r, nonnull);
sub(r, r, rheapbase);
bind(nonnull);
lsr(r, r, LogMinObjAlignmentInBytes);
*/
}
}
void MacroAssembler::encode_heap_oop_not_null(Register r) {
#ifdef ASSERT
verify_heapbase("MacroAssembler::encode_heap_oop_not_null: heap base corrupted?");
if (CheckCompressedOops) {
Label ok;
cbnz(r, ok);
stop("null oop passed to encode_heap_oop_not_null");
bind(ok);
}
#endif
verify_oop_msg(r, "broken oop in encode_heap_oop_not_null");
if (CompressedOops::base() != nullptr) {
sub(r, r, rheapbase);
}
if (CompressedOops::shift() != 0) {
assert (LogMinObjAlignmentInBytes == CompressedOops::shift(), "decode alg wrong");
lsr(r, r, LogMinObjAlignmentInBytes);
}
}
void MacroAssembler::encode_heap_oop_not_null(Register dst, Register src) {
#ifdef ASSERT
verify_heapbase("MacroAssembler::encode_heap_oop_not_null2: heap base corrupted?");
if (CheckCompressedOops) {
Label ok;
cbnz(src, ok);
stop("null oop passed to encode_heap_oop_not_null2");
bind(ok);
}
#endif
verify_oop_msg(src, "broken oop in encode_heap_oop_not_null2");
Register data = src;
if (CompressedOops::base() != nullptr) {
sub(dst, src, rheapbase);
data = dst;
}
if (CompressedOops::shift() != 0) {
assert (LogMinObjAlignmentInBytes == CompressedOops::shift(), "decode alg wrong");
lsr(dst, data, LogMinObjAlignmentInBytes);
data = dst;
}
if (data == src)
mov(dst, src);
}
void MacroAssembler::decode_heap_oop(Register d, Register s) {
#ifdef ASSERT
verify_heapbase("MacroAssembler::decode_heap_oop: heap base corrupted?");
#endif
if (CompressedOops::base() == nullptr) {
if (CompressedOops::shift() != 0) {
lsl(d, s, CompressedOops::shift());
} else if (d != s) {
mov(d, s);
}
} else {
Label done;
if (d != s)
mov(d, s);
cbz(s, done);
add(d, rheapbase, s, Assembler::LSL, LogMinObjAlignmentInBytes);
bind(done);
}
verify_oop_msg(d, "broken oop in decode_heap_oop");
}
void MacroAssembler::decode_heap_oop_not_null(Register r) {
assert (UseCompressedOops, "should only be used for compressed headers");
assert (Universe::heap() != nullptr, "java heap should be initialized");
// Cannot assert, unverified entry point counts instructions (see .ad file)
// vtableStubs also counts instructions in pd_code_size_limit.
// Also do not verify_oop as this is called by verify_oop.
if (CompressedOops::shift() != 0) {
assert(LogMinObjAlignmentInBytes == CompressedOops::shift(), "decode alg wrong");
if (CompressedOops::base() != nullptr) {
add(r, rheapbase, r, Assembler::LSL, LogMinObjAlignmentInBytes);
} else {
add(r, zr, r, Assembler::LSL, LogMinObjAlignmentInBytes);
}
} else {
assert (CompressedOops::base() == nullptr, "sanity");
}
}
void MacroAssembler::decode_heap_oop_not_null(Register dst, Register src) {
assert (UseCompressedOops, "should only be used for compressed headers");
assert (Universe::heap() != nullptr, "java heap should be initialized");
// Cannot assert, unverified entry point counts instructions (see .ad file)
// vtableStubs also counts instructions in pd_code_size_limit.
// Also do not verify_oop as this is called by verify_oop.
if (CompressedOops::shift() != 0) {
assert(LogMinObjAlignmentInBytes == CompressedOops::shift(), "decode alg wrong");
if (CompressedOops::base() != nullptr) {
add(dst, rheapbase, src, Assembler::LSL, LogMinObjAlignmentInBytes);
} else {
add(dst, zr, src, Assembler::LSL, LogMinObjAlignmentInBytes);
}
} else {
assert (CompressedOops::base() == nullptr, "sanity");
if (dst != src) {
mov(dst, src);
}
}
}
MacroAssembler::KlassDecodeMode MacroAssembler::_klass_decode_mode(KlassDecodeNone);
MacroAssembler::KlassDecodeMode MacroAssembler::klass_decode_mode() {
assert(Metaspace::initialized(), "metaspace not initialized yet");
assert(_klass_decode_mode != KlassDecodeNone, "should be initialized");
return _klass_decode_mode;
}
MacroAssembler::KlassDecodeMode MacroAssembler::klass_decode_mode(address base, int shift, const size_t range) {
assert(UseCompressedClassPointers, "not using compressed class pointers");
// KlassDecodeMode shouldn't be set already.
assert(_klass_decode_mode == KlassDecodeNone, "set once");
if (base == nullptr) {
return KlassDecodeZero;
}
if (operand_valid_for_logical_immediate(
/*is32*/false, (uint64_t)base)) {
const uint64_t range_mask = right_n_bits(log2i_ceil(range));
if (((uint64_t)base & range_mask) == 0) {
return KlassDecodeXor;
}
}
const uint64_t shifted_base =
(uint64_t)base >> shift;
if ((shifted_base & 0xffff0000ffffffff) == 0) {
return KlassDecodeMovk;
}
// No valid encoding.
return KlassDecodeNone;
}
// Check if one of the above decoding modes will work for given base, shift and range.
bool MacroAssembler::check_klass_decode_mode(address base, int shift, const size_t range) {
return klass_decode_mode(base, shift, range) != KlassDecodeNone;
}
bool MacroAssembler::set_klass_decode_mode(address base, int shift, const size_t range) {
_klass_decode_mode = klass_decode_mode(base, shift, range);
return _klass_decode_mode != KlassDecodeNone;
}
static Register pick_different_tmp(Register dst, Register src) {
auto tmps = RegSet::of(r0, r1, r2) - RegSet::of(src, dst);
return *tmps.begin();
}
void MacroAssembler::encode_klass_not_null_for_aot(Register dst, Register src) {
// we have to load the klass base from the AOT constants area but
// not the shift because it is not allowed to change
int shift = CompressedKlassPointers::shift();
assert(shift >= 0 && shift <= CompressedKlassPointers::max_shift(), "unexpected compressed klass shift!");
if (dst != src) {
// we can load the base into dst, subtract it formthe src and shift down
lea(dst, ExternalAddress(CompressedKlassPointers::base_addr()));
ldr(dst, dst);
sub(dst, src, dst);
lsr(dst, dst, shift);
} else {
// we need an extra register in order to load the coop base
Register tmp = pick_different_tmp(dst, src);
RegSet regs = RegSet::of(tmp);
push(regs, sp);
lea(tmp, ExternalAddress(CompressedKlassPointers::base_addr()));
ldr(tmp, tmp);
sub(dst, src, tmp);
lsr(dst, dst, shift);
pop(regs, sp);
}
}
void MacroAssembler::encode_klass_not_null(Register dst, Register src) {
if (AOTCodeCache::is_on_for_dump()) {
encode_klass_not_null_for_aot(dst, src);
return;
}
switch (klass_decode_mode()) {
case KlassDecodeZero:
if (CompressedKlassPointers::shift() != 0) {
lsr(dst, src, CompressedKlassPointers::shift());
} else {
if (dst != src) mov(dst, src);
}
break;
case KlassDecodeXor:
if (CompressedKlassPointers::shift() != 0) {
eor(dst, src, (uint64_t)CompressedKlassPointers::base());
lsr(dst, dst, CompressedKlassPointers::shift());
} else {
eor(dst, src, (uint64_t)CompressedKlassPointers::base());
}
break;
case KlassDecodeMovk:
if (CompressedKlassPointers::shift() != 0) {
ubfx(dst, src, CompressedKlassPointers::shift(), 32);
} else {
movw(dst, src);
}
break;
case KlassDecodeNone:
ShouldNotReachHere();
break;
}
}
void MacroAssembler::encode_klass_not_null(Register r) {
encode_klass_not_null(r, r);
}
void MacroAssembler::decode_klass_not_null_for_aot(Register dst, Register src) {
// we have to load the klass base from the AOT constants area but
// not the shift because it is not allowed to change
int shift = CompressedKlassPointers::shift();
assert(shift >= 0 && shift <= CompressedKlassPointers::max_shift(), "unexpected compressed klass shift!");
if (dst != src) {
// we can load the base into dst then add the offset with a suitable shift
lea(dst, ExternalAddress(CompressedKlassPointers::base_addr()));
ldr(dst, dst);
add(dst, dst, src, LSL, shift);
} else {
// we need an extra register in order to load the coop base
Register tmp = pick_different_tmp(dst, src);
RegSet regs = RegSet::of(tmp);
push(regs, sp);
lea(tmp, ExternalAddress(CompressedKlassPointers::base_addr()));
ldr(tmp, tmp);
add(dst, tmp, src, LSL, shift);
pop(regs, sp);
}
}
void MacroAssembler::decode_klass_not_null(Register dst, Register src) {
assert (UseCompressedClassPointers, "should only be used for compressed headers");
if (AOTCodeCache::is_on_for_dump()) {
decode_klass_not_null_for_aot(dst, src);
return;
}
switch (klass_decode_mode()) {
case KlassDecodeZero:
if (CompressedKlassPointers::shift() != 0) {
lsl(dst, src, CompressedKlassPointers::shift());
} else {
if (dst != src) mov(dst, src);
}
break;
case KlassDecodeXor:
if (CompressedKlassPointers::shift() != 0) {
lsl(dst, src, CompressedKlassPointers::shift());
eor(dst, dst, (uint64_t)CompressedKlassPointers::base());
} else {
eor(dst, src, (uint64_t)CompressedKlassPointers::base());
}
break;
case KlassDecodeMovk: {
const uint64_t shifted_base =
(uint64_t)CompressedKlassPointers::base() >> CompressedKlassPointers::shift();
if (dst != src) movw(dst, src);
movk(dst, shifted_base >> 32, 32);
if (CompressedKlassPointers::shift() != 0) {
lsl(dst, dst, CompressedKlassPointers::shift());
}
break;
}
case KlassDecodeNone:
ShouldNotReachHere();
break;
}
}
void MacroAssembler::decode_klass_not_null(Register r) {
decode_klass_not_null(r, r);
}
void MacroAssembler::set_narrow_oop(Register dst, jobject obj) {
#ifdef ASSERT
{
ThreadInVMfromUnknown tiv;
assert (UseCompressedOops, "should only be used for compressed oops");
assert (Universe::heap() != nullptr, "java heap should be initialized");
assert (oop_recorder() != nullptr, "this assembler needs an OopRecorder");
assert(Universe::heap()->is_in(JNIHandles::resolve(obj)), "should be real oop");
}
#endif
int oop_index = oop_recorder()->find_index(obj);
InstructionMark im(this);
RelocationHolder rspec = oop_Relocation::spec(oop_index);
code_section()->relocate(inst_mark(), rspec);
movz(dst, 0xDEAD, 16);
movk(dst, 0xBEEF);
}
void MacroAssembler::set_narrow_klass(Register dst, Klass* k) {
assert (UseCompressedClassPointers, "should only be used for compressed headers");
assert (oop_recorder() != nullptr, "this assembler needs an OopRecorder");
int index = oop_recorder()->find_index(k);
assert(! Universe::heap()->is_in(k), "should not be an oop");
InstructionMark im(this);
RelocationHolder rspec = metadata_Relocation::spec(index);
code_section()->relocate(inst_mark(), rspec);
narrowKlass nk = CompressedKlassPointers::encode(k);
movz(dst, (nk >> 16), 16);
movk(dst, nk & 0xffff);
}
void MacroAssembler::access_load_at(BasicType type, DecoratorSet decorators,
Register dst, Address src,
Register tmp1, Register tmp2) {
BarrierSetAssembler *bs = BarrierSet::barrier_set()->barrier_set_assembler();
decorators = AccessInternal::decorator_fixup(decorators, type);
bool as_raw = (decorators & AS_RAW) != 0;
if (as_raw) {
bs->BarrierSetAssembler::load_at(this, decorators, type, dst, src, tmp1, tmp2);
} else {
bs->load_at(this, decorators, type, dst, src, tmp1, tmp2);
}
}
void MacroAssembler::access_store_at(BasicType type, DecoratorSet decorators,
Address dst, Register val,
Register tmp1, Register tmp2, Register tmp3) {
BarrierSetAssembler *bs = BarrierSet::barrier_set()->barrier_set_assembler();
decorators = AccessInternal::decorator_fixup(decorators, type);
bool as_raw = (decorators & AS_RAW) != 0;
if (as_raw) {
bs->BarrierSetAssembler::store_at(this, decorators, type, dst, val, tmp1, tmp2, tmp3);
} else {
bs->store_at(this, decorators, type, dst, val, tmp1, tmp2, tmp3);
}
}
void MacroAssembler::load_heap_oop(Register dst, Address src, Register tmp1,
Register tmp2, DecoratorSet decorators) {
access_load_at(T_OBJECT, IN_HEAP | decorators, dst, src, tmp1, tmp2);
}
void MacroAssembler::load_heap_oop_not_null(Register dst, Address src, Register tmp1,
Register tmp2, DecoratorSet decorators) {
access_load_at(T_OBJECT, IN_HEAP | IS_NOT_NULL | decorators, dst, src, tmp1, tmp2);
}
void MacroAssembler::store_heap_oop(Address dst, Register val, Register tmp1,
Register tmp2, Register tmp3, DecoratorSet decorators) {
access_store_at(T_OBJECT, IN_HEAP | decorators, dst, val, tmp1, tmp2, tmp3);
}
// Used for storing nulls.
void MacroAssembler::store_heap_oop_null(Address dst) {
access_store_at(T_OBJECT, IN_HEAP, dst, noreg, noreg, noreg, noreg);
}
Address MacroAssembler::allocate_metadata_address(Metadata* obj) {
assert(oop_recorder() != nullptr, "this assembler needs a Recorder");
int index = oop_recorder()->allocate_metadata_index(obj);
RelocationHolder rspec = metadata_Relocation::spec(index);
return Address((address)obj, rspec);
}
// Move an oop into a register.
void MacroAssembler::movoop(Register dst, jobject obj) {
int oop_index;
if (obj == nullptr) {
oop_index = oop_recorder()->allocate_oop_index(obj);
} else {
#ifdef ASSERT
{
ThreadInVMfromUnknown tiv;
assert(Universe::heap()->is_in(JNIHandles::resolve(obj)), "should be real oop");
}
#endif
oop_index = oop_recorder()->find_index(obj);
}
RelocationHolder rspec = oop_Relocation::spec(oop_index);
if (BarrierSet::barrier_set()->barrier_set_assembler()->supports_instruction_patching()) {
mov(dst, Address((address)obj, rspec));
} else {
address dummy = address(uintptr_t(pc()) & -wordSize); // A nearby aligned address
ldr(dst, Address(dummy, rspec));
}
}
// Move a metadata address into a register.
void MacroAssembler::mov_metadata(Register dst, Metadata* obj) {
int oop_index;
if (obj == nullptr) {
oop_index = oop_recorder()->allocate_metadata_index(obj);
} else {
oop_index = oop_recorder()->find_index(obj);
}
RelocationHolder rspec = metadata_Relocation::spec(oop_index);
mov(dst, Address((address)obj, rspec));
}
Address MacroAssembler::constant_oop_address(jobject obj) {
#ifdef ASSERT
{
ThreadInVMfromUnknown tiv;
assert(oop_recorder() != nullptr, "this assembler needs an OopRecorder");
assert(Universe::heap()->is_in(JNIHandles::resolve(obj)), "not an oop");
}
#endif
int oop_index = oop_recorder()->find_index(obj);
return Address((address)obj, oop_Relocation::spec(oop_index));
}
// Defines obj, preserves var_size_in_bytes, okay for t2 == var_size_in_bytes.
void MacroAssembler::tlab_allocate(Register obj,
Register var_size_in_bytes,
int con_size_in_bytes,
Register t1,
Register t2,
Label& slow_case) {
BarrierSetAssembler *bs = BarrierSet::barrier_set()->barrier_set_assembler();
bs->tlab_allocate(this, obj, var_size_in_bytes, con_size_in_bytes, t1, t2, slow_case);
}
void MacroAssembler::inc_held_monitor_count(Register tmp) {
Address dst(rthread, JavaThread::held_monitor_count_offset());
#ifdef ASSERT
ldr(tmp, dst);
increment(tmp);
str(tmp, dst);
Label ok;
tbz(tmp, 63, ok);
STOP("assert(held monitor count underflow)");
should_not_reach_here();
bind(ok);
#else
increment(dst);
#endif
}
void MacroAssembler::dec_held_monitor_count(Register tmp) {
Address dst(rthread, JavaThread::held_monitor_count_offset());
#ifdef ASSERT
ldr(tmp, dst);
decrement(tmp);
str(tmp, dst);
Label ok;
tbz(tmp, 63, ok);
STOP("assert(held monitor count underflow)");
should_not_reach_here();
bind(ok);
#else
decrement(dst);
#endif
}
void MacroAssembler::verify_tlab() {
#ifdef ASSERT
if (UseTLAB && VerifyOops) {
Label next, ok;
stp(rscratch2, rscratch1, Address(pre(sp, -16)));
ldr(rscratch2, Address(rthread, in_bytes(JavaThread::tlab_top_offset())));
ldr(rscratch1, Address(rthread, in_bytes(JavaThread::tlab_start_offset())));
cmp(rscratch2, rscratch1);
br(Assembler::HS, next);
STOP("assert(top >= start)");
should_not_reach_here();
bind(next);
ldr(rscratch2, Address(rthread, in_bytes(JavaThread::tlab_end_offset())));
ldr(rscratch1, Address(rthread, in_bytes(JavaThread::tlab_top_offset())));
cmp(rscratch2, rscratch1);
br(Assembler::HS, ok);
STOP("assert(top <= end)");
should_not_reach_here();
bind(ok);
ldp(rscratch2, rscratch1, Address(post(sp, 16)));
}
#endif
}
// Writes to stack successive pages until offset reached to check for
// stack overflow + shadow pages. This clobbers tmp.
void MacroAssembler::bang_stack_size(Register size, Register tmp) {
assert_different_registers(tmp, size, rscratch1);
mov(tmp, sp);
// Bang stack for total size given plus shadow page size.
// Bang one page at a time because large size can bang beyond yellow and
// red zones.
Label loop;
mov(rscratch1, (int)os::vm_page_size());
bind(loop);
lea(tmp, Address(tmp, -(int)os::vm_page_size()));
subsw(size, size, rscratch1);
str(size, Address(tmp));
br(Assembler::GT, loop);
// Bang down shadow pages too.
// At this point, (tmp-0) is the last address touched, so don't
// touch it again. (It was touched as (tmp-pagesize) but then tmp
// was post-decremented.) Skip this address by starting at i=1, and
// touch a few more pages below. N.B. It is important to touch all
// the way down to and including i=StackShadowPages.
for (int i = 0; i < (int)(StackOverflow::stack_shadow_zone_size() / (int)os::vm_page_size()) - 1; i++) {
// this could be any sized move but this is can be a debugging crumb
// so the bigger the better.
lea(tmp, Address(tmp, -(int)os::vm_page_size()));
str(size, Address(tmp));
}
}
// Move the address of the polling page into dest.
void MacroAssembler::get_polling_page(Register dest, relocInfo::relocType rtype) {
ldr(dest, Address(rthread, JavaThread::polling_page_offset()));
}
// Read the polling page. The address of the polling page must
// already be in r.
address MacroAssembler::read_polling_page(Register r, relocInfo::relocType rtype) {
address mark;
{
InstructionMark im(this);
code_section()->relocate(inst_mark(), rtype);
ldrw(zr, Address(r, 0));
mark = inst_mark();
}
verify_cross_modify_fence_not_required();
return mark;
}
void MacroAssembler::adrp(Register reg1, const Address &dest, uint64_t &byte_offset) {
relocInfo::relocType rtype = dest.rspec().reloc()->type();
uint64_t low_page = (uint64_t)CodeCache::low_bound() >> 12;
uint64_t high_page = (uint64_t)(CodeCache::high_bound()-1) >> 12;
uint64_t dest_page = (uint64_t)dest.target() >> 12;
int64_t offset_low = dest_page - low_page;
int64_t offset_high = dest_page - high_page;
assert(is_valid_AArch64_address(dest.target()), "bad address");
assert(dest.getMode() == Address::literal, "ADRP must be applied to a literal address");
InstructionMark im(this);
code_section()->relocate(inst_mark(), dest.rspec());
// 8143067: Ensure that the adrp can reach the dest from anywhere within
// the code cache so that if it is relocated we know it will still reach
if (offset_high >= -(1<<20) && offset_low < (1<<20)) {
_adrp(reg1, dest.target());
} else {
uint64_t target = (uint64_t)dest.target();
uint64_t adrp_target
= (target & 0xffffffffULL) | ((uint64_t)pc() & 0xffff00000000ULL);
_adrp(reg1, (address)adrp_target);
movk(reg1, target >> 32, 32);
}
byte_offset = (uint64_t)dest.target() & 0xfff;
}
void MacroAssembler::load_byte_map_base(Register reg) {
CardTable::CardValue* byte_map_base =
((CardTableBarrierSet*)(BarrierSet::barrier_set()))->card_table()->byte_map_base();
// Strictly speaking the byte_map_base isn't an address at all, and it might
// even be negative. It is thus materialised as a constant.
mov(reg, (uint64_t)byte_map_base);
}
void MacroAssembler::build_frame(int framesize) {
assert(framesize >= 2 * wordSize, "framesize must include space for FP/LR");
assert(framesize % (2*wordSize) == 0, "must preserve 2*wordSize alignment");
protect_return_address();
if (framesize < ((1 << 9) + 2 * wordSize)) {
sub(sp, sp, framesize);
stp(rfp, lr, Address(sp, framesize - 2 * wordSize));
if (PreserveFramePointer) add(rfp, sp, framesize - 2 * wordSize);
} else {
stp(rfp, lr, Address(pre(sp, -2 * wordSize)));
if (PreserveFramePointer) mov(rfp, sp);
if (framesize < ((1 << 12) + 2 * wordSize))
sub(sp, sp, framesize - 2 * wordSize);
else {
mov(rscratch1, framesize - 2 * wordSize);
sub(sp, sp, rscratch1);
}
}
verify_cross_modify_fence_not_required();
}
void MacroAssembler::remove_frame(int framesize) {
assert(framesize >= 2 * wordSize, "framesize must include space for FP/LR");
assert(framesize % (2*wordSize) == 0, "must preserve 2*wordSize alignment");
if (framesize < ((1 << 9) + 2 * wordSize)) {
ldp(rfp, lr, Address(sp, framesize - 2 * wordSize));
add(sp, sp, framesize);
} else {
if (framesize < ((1 << 12) + 2 * wordSize))
add(sp, sp, framesize - 2 * wordSize);
else {
mov(rscratch1, framesize - 2 * wordSize);
add(sp, sp, rscratch1);
}
ldp(rfp, lr, Address(post(sp, 2 * wordSize)));
}
authenticate_return_address();
}
// This method counts leading positive bytes (highest bit not set) in provided byte array
address MacroAssembler::count_positives(Register ary1, Register len, Register result) {
// Simple and most common case of aligned small array which is not at the
// end of memory page is placed here. All other cases are in stub.
Label LOOP, END, STUB, STUB_LONG, SET_RESULT, DONE;
const uint64_t UPPER_BIT_MASK=0x8080808080808080;
assert_different_registers(ary1, len, result);
mov(result, len);
cmpw(len, 0);
br(LE, DONE);
cmpw(len, 4 * wordSize);
br(GE, STUB_LONG); // size > 32 then go to stub
int shift = 64 - exact_log2(os::vm_page_size());
lsl(rscratch1, ary1, shift);
mov(rscratch2, (size_t)(4 * wordSize) << shift);
adds(rscratch2, rscratch1, rscratch2); // At end of page?
br(CS, STUB); // at the end of page then go to stub
subs(len, len, wordSize);
br(LT, END);
BIND(LOOP);
ldr(rscratch1, Address(post(ary1, wordSize)));
tst(rscratch1, UPPER_BIT_MASK);
br(NE, SET_RESULT);
subs(len, len, wordSize);
br(GE, LOOP);
cmpw(len, -wordSize);
br(EQ, DONE);
BIND(END);
ldr(rscratch1, Address(ary1));
sub(rscratch2, zr, len, LSL, 3); // LSL 3 is to get bits from bytes
lslv(rscratch1, rscratch1, rscratch2);
tst(rscratch1, UPPER_BIT_MASK);
br(NE, SET_RESULT);
b(DONE);
BIND(STUB);
RuntimeAddress count_pos = RuntimeAddress(StubRoutines::aarch64::count_positives());
assert(count_pos.target() != nullptr, "count_positives stub has not been generated");
address tpc1 = trampoline_call(count_pos);
if (tpc1 == nullptr) {
DEBUG_ONLY(reset_labels(STUB_LONG, SET_RESULT, DONE));
postcond(pc() == badAddress);
return nullptr;
}
b(DONE);
BIND(STUB_LONG);
RuntimeAddress count_pos_long = RuntimeAddress(StubRoutines::aarch64::count_positives_long());
assert(count_pos_long.target() != nullptr, "count_positives_long stub has not been generated");
address tpc2 = trampoline_call(count_pos_long);
if (tpc2 == nullptr) {
DEBUG_ONLY(reset_labels(SET_RESULT, DONE));
postcond(pc() == badAddress);
return nullptr;
}
b(DONE);
BIND(SET_RESULT);
add(len, len, wordSize);
sub(result, result, len);
BIND(DONE);
postcond(pc() != badAddress);
return pc();
}
// Clobbers: rscratch1, rscratch2, rflags
// May also clobber v0-v7 when (!UseSimpleArrayEquals && UseSIMDForArrayEquals)
address MacroAssembler::arrays_equals(Register a1, Register a2, Register tmp3,
Register tmp4, Register tmp5, Register result,
Register cnt1, int elem_size) {
Label DONE, SAME;
Register tmp1 = rscratch1;
Register tmp2 = rscratch2;
int elem_per_word = wordSize/elem_size;
int log_elem_size = exact_log2(elem_size);
int klass_offset = arrayOopDesc::klass_offset_in_bytes();
int length_offset = arrayOopDesc::length_offset_in_bytes();
int base_offset
= arrayOopDesc::base_offset_in_bytes(elem_size == 2 ? T_CHAR : T_BYTE);
// When the length offset is not aligned to 8 bytes,
// then we align it down. This is valid because the new
// offset will always be the klass which is the same
// for type arrays.
int start_offset = align_down(length_offset, BytesPerWord);
int extra_length = base_offset - start_offset;
assert(start_offset == length_offset || start_offset == klass_offset,
"start offset must be 8-byte-aligned or be the klass offset");
assert(base_offset != start_offset, "must include the length field");
extra_length = extra_length / elem_size; // We count in elements, not bytes.
int stubBytesThreshold = 3 * 64 + (UseSIMDForArrayEquals ? 0 : 16);
assert(elem_size == 1 || elem_size == 2, "must be char or byte");
assert_different_registers(a1, a2, result, cnt1, rscratch1, rscratch2);
#ifndef PRODUCT
{
const char kind = (elem_size == 2) ? 'U' : 'L';
char comment[64];
snprintf(comment, sizeof comment, "array_equals%c{", kind);
BLOCK_COMMENT(comment);
}
#endif
// if (a1 == a2)
// return true;
cmpoop(a1, a2); // May have read barriers for a1 and a2.
br(EQ, SAME);
if (UseSimpleArrayEquals) {
Label NEXT_WORD, SHORT, TAIL03, TAIL01, A_MIGHT_BE_NULL, A_IS_NOT_NULL;
// if (a1 == nullptr || a2 == nullptr)
// return false;
// a1 & a2 == 0 means (some-pointer is null) or
// (very-rare-or-even-probably-impossible-pointer-values)
// so, we can save one branch in most cases
tst(a1, a2);
mov(result, false);
br(EQ, A_MIGHT_BE_NULL);
// if (a1.length != a2.length)
// return false;
bind(A_IS_NOT_NULL);
ldrw(cnt1, Address(a1, length_offset));
// Increase loop counter by diff between base- and actual start-offset.
addw(cnt1, cnt1, extra_length);
lea(a1, Address(a1, start_offset));
lea(a2, Address(a2, start_offset));
// Check for short strings, i.e. smaller than wordSize.
subs(cnt1, cnt1, elem_per_word);
br(Assembler::LT, SHORT);
// Main 8 byte comparison loop.
bind(NEXT_WORD); {
ldr(tmp1, Address(post(a1, wordSize)));
ldr(tmp2, Address(post(a2, wordSize)));
subs(cnt1, cnt1, elem_per_word);
eor(tmp5, tmp1, tmp2);
cbnz(tmp5, DONE);
} br(GT, NEXT_WORD);
// Last longword. In the case where length == 4 we compare the
// same longword twice, but that's still faster than another
// conditional branch.
// cnt1 could be 0, -1, -2, -3, -4 for chars; -4 only happens when
// length == 4.
if (log_elem_size > 0)
lsl(cnt1, cnt1, log_elem_size);
ldr(tmp3, Address(a1, cnt1));
ldr(tmp4, Address(a2, cnt1));
eor(tmp5, tmp3, tmp4);
cbnz(tmp5, DONE);
b(SAME);
bind(A_MIGHT_BE_NULL);
// in case both a1 and a2 are not-null, proceed with loads
cbz(a1, DONE);
cbz(a2, DONE);
b(A_IS_NOT_NULL);
bind(SHORT);
tbz(cnt1, 2 - log_elem_size, TAIL03); // 0-7 bytes left.
{
ldrw(tmp1, Address(post(a1, 4)));
ldrw(tmp2, Address(post(a2, 4)));
eorw(tmp5, tmp1, tmp2);
cbnzw(tmp5, DONE);
}
bind(TAIL03);
tbz(cnt1, 1 - log_elem_size, TAIL01); // 0-3 bytes left.
{
ldrh(tmp3, Address(post(a1, 2)));
ldrh(tmp4, Address(post(a2, 2)));
eorw(tmp5, tmp3, tmp4);
cbnzw(tmp5, DONE);
}
bind(TAIL01);
if (elem_size == 1) { // Only needed when comparing byte arrays.
tbz(cnt1, 0, SAME); // 0-1 bytes left.
{
ldrb(tmp1, a1);
ldrb(tmp2, a2);
eorw(tmp5, tmp1, tmp2);
cbnzw(tmp5, DONE);
}
}
} else {
Label NEXT_DWORD, SHORT, TAIL, TAIL2, STUB,
CSET_EQ, LAST_CHECK;
mov(result, false);
cbz(a1, DONE);
ldrw(cnt1, Address(a1, length_offset));
cbz(a2, DONE);
// Increase loop counter by diff between base- and actual start-offset.
addw(cnt1, cnt1, extra_length);
// on most CPUs a2 is still "locked"(surprisingly) in ldrw and it's
// faster to perform another branch before comparing a1 and a2
cmp(cnt1, (u1)elem_per_word);
br(LE, SHORT); // short or same
ldr(tmp3, Address(pre(a1, start_offset)));
subs(zr, cnt1, stubBytesThreshold);
br(GE, STUB);
ldr(tmp4, Address(pre(a2, start_offset)));
sub(tmp5, zr, cnt1, LSL, 3 + log_elem_size);
// Main 16 byte comparison loop with 2 exits
bind(NEXT_DWORD); {
ldr(tmp1, Address(pre(a1, wordSize)));
ldr(tmp2, Address(pre(a2, wordSize)));
subs(cnt1, cnt1, 2 * elem_per_word);
br(LE, TAIL);
eor(tmp4, tmp3, tmp4);
cbnz(tmp4, DONE);
ldr(tmp3, Address(pre(a1, wordSize)));
ldr(tmp4, Address(pre(a2, wordSize)));
cmp(cnt1, (u1)elem_per_word);
br(LE, TAIL2);
cmp(tmp1, tmp2);
} br(EQ, NEXT_DWORD);
b(DONE);
bind(TAIL);
eor(tmp4, tmp3, tmp4);
eor(tmp2, tmp1, tmp2);
lslv(tmp2, tmp2, tmp5);
orr(tmp5, tmp4, tmp2);
cmp(tmp5, zr);
b(CSET_EQ);
bind(TAIL2);
eor(tmp2, tmp1, tmp2);
cbnz(tmp2, DONE);
b(LAST_CHECK);
bind(STUB);
ldr(tmp4, Address(pre(a2, start_offset)));
if (elem_size == 2) { // convert to byte counter
lsl(cnt1, cnt1, 1);
}
eor(tmp5, tmp3, tmp4);
cbnz(tmp5, DONE);
RuntimeAddress stub = RuntimeAddress(StubRoutines::aarch64::large_array_equals());
assert(stub.target() != nullptr, "array_equals_long stub has not been generated");
address tpc = trampoline_call(stub);
if (tpc == nullptr) {
DEBUG_ONLY(reset_labels(SHORT, LAST_CHECK, CSET_EQ, SAME, DONE));
postcond(pc() == badAddress);
return nullptr;
}
b(DONE);
// (a1 != null && a2 == null) || (a1 != null && a2 != null && a1 == a2)
// so, if a2 == null => return false(0), else return true, so we can return a2
mov(result, a2);
b(DONE);
bind(SHORT);
sub(tmp5, zr, cnt1, LSL, 3 + log_elem_size);
ldr(tmp3, Address(a1, start_offset));
ldr(tmp4, Address(a2, start_offset));
bind(LAST_CHECK);
eor(tmp4, tmp3, tmp4);
lslv(tmp5, tmp4, tmp5);
cmp(tmp5, zr);
bind(CSET_EQ);
cset(result, EQ);
b(DONE);
}
bind(SAME);
mov(result, true);
// That's it.
bind(DONE);
BLOCK_COMMENT("} array_equals");
postcond(pc() != badAddress);
return pc();
}
// Compare Strings
// For Strings we're passed the address of the first characters in a1
// and a2 and the length in cnt1.
// There are two implementations. For arrays >= 8 bytes, all
// comparisons (including the final one, which may overlap) are
// performed 8 bytes at a time. For strings < 8 bytes, we compare a
// halfword, then a short, and then a byte.
void MacroAssembler::string_equals(Register a1, Register a2,
Register result, Register cnt1)
{
Label SAME, DONE, SHORT, NEXT_WORD;
Register tmp1 = rscratch1;
Register tmp2 = rscratch2;
Register cnt2 = tmp2; // cnt2 only used in array length compare
assert_different_registers(a1, a2, result, cnt1, rscratch1, rscratch2);
#ifndef PRODUCT
{
char comment[64];
snprintf(comment, sizeof comment, "{string_equalsL");
BLOCK_COMMENT(comment);
}
#endif
mov(result, false);
// Check for short strings, i.e. smaller than wordSize.
subs(cnt1, cnt1, wordSize);
br(Assembler::LT, SHORT);
// Main 8 byte comparison loop.
bind(NEXT_WORD); {
ldr(tmp1, Address(post(a1, wordSize)));
ldr(tmp2, Address(post(a2, wordSize)));
subs(cnt1, cnt1, wordSize);
eor(tmp1, tmp1, tmp2);
cbnz(tmp1, DONE);
} br(GT, NEXT_WORD);
// Last longword. In the case where length == 4 we compare the
// same longword twice, but that's still faster than another
// conditional branch.
// cnt1 could be 0, -1, -2, -3, -4 for chars; -4 only happens when
// length == 4.
ldr(tmp1, Address(a1, cnt1));
ldr(tmp2, Address(a2, cnt1));
eor(tmp2, tmp1, tmp2);
cbnz(tmp2, DONE);
b(SAME);
bind(SHORT);
Label TAIL03, TAIL01;
tbz(cnt1, 2, TAIL03); // 0-7 bytes left.
{
ldrw(tmp1, Address(post(a1, 4)));
ldrw(tmp2, Address(post(a2, 4)));
eorw(tmp1, tmp1, tmp2);
cbnzw(tmp1, DONE);
}
bind(TAIL03);
tbz(cnt1, 1, TAIL01); // 0-3 bytes left.
{
ldrh(tmp1, Address(post(a1, 2)));
ldrh(tmp2, Address(post(a2, 2)));
eorw(tmp1, tmp1, tmp2);
cbnzw(tmp1, DONE);
}
bind(TAIL01);
tbz(cnt1, 0, SAME); // 0-1 bytes left.
{
ldrb(tmp1, a1);
ldrb(tmp2, a2);
eorw(tmp1, tmp1, tmp2);
cbnzw(tmp1, DONE);
}
// Arrays are equal.
bind(SAME);
mov(result, true);
// That's it.
bind(DONE);
BLOCK_COMMENT("} string_equals");
}
// The size of the blocks erased by the zero_blocks stub. We must
// handle anything smaller than this ourselves in zero_words().
const int MacroAssembler::zero_words_block_size = 8;
// zero_words() is used by C2 ClearArray patterns and by
// C1_MacroAssembler. It is as small as possible, handling small word
// counts locally and delegating anything larger to the zero_blocks
// stub. It is expanded many times in compiled code, so it is
// important to keep it short.
// ptr: Address of a buffer to be zeroed.
// cnt: Count in HeapWords.
//
// ptr, cnt, rscratch1, and rscratch2 are clobbered.
address MacroAssembler::zero_words(Register ptr, Register cnt)
{
assert(is_power_of_2(zero_words_block_size), "adjust this");
BLOCK_COMMENT("zero_words {");
assert(ptr == r10 && cnt == r11, "mismatch in register usage");
RuntimeAddress zero_blocks = RuntimeAddress(StubRoutines::aarch64::zero_blocks());
assert(zero_blocks.target() != nullptr, "zero_blocks stub has not been generated");
subs(rscratch1, cnt, zero_words_block_size);
Label around;
br(LO, around);
{
RuntimeAddress zero_blocks = RuntimeAddress(StubRoutines::aarch64::zero_blocks());
assert(zero_blocks.target() != nullptr, "zero_blocks stub has not been generated");
// Make sure this is a C2 compilation. C1 allocates space only for
// trampoline stubs generated by Call LIR ops, and in any case it
// makes sense for a C1 compilation task to proceed as quickly as
// possible.
CompileTask* task;
if (StubRoutines::aarch64::complete()
&& Thread::current()->is_Compiler_thread()
&& (task = ciEnv::current()->task())
&& is_c2_compile(task->comp_level())) {
address tpc = trampoline_call(zero_blocks);
if (tpc == nullptr) {
DEBUG_ONLY(reset_labels(around));
return nullptr;
}
} else {
far_call(zero_blocks);
}
}
bind(around);
// We have a few words left to do. zero_blocks has adjusted r10 and r11
// for us.
for (int i = zero_words_block_size >> 1; i > 1; i >>= 1) {
Label l;
tbz(cnt, exact_log2(i), l);
for (int j = 0; j < i; j += 2) {
stp(zr, zr, post(ptr, 2 * BytesPerWord));
}
bind(l);
}
{
Label l;
tbz(cnt, 0, l);
str(zr, Address(ptr));
bind(l);
}
BLOCK_COMMENT("} zero_words");
return pc();
}
// base: Address of a buffer to be zeroed, 8 bytes aligned.
// cnt: Immediate count in HeapWords.
//
// r10, r11, rscratch1, and rscratch2 are clobbered.
address MacroAssembler::zero_words(Register base, uint64_t cnt)
{
assert(wordSize <= BlockZeroingLowLimit,
"increase BlockZeroingLowLimit");
address result = nullptr;
if (cnt <= (uint64_t)BlockZeroingLowLimit / BytesPerWord) {
#ifndef PRODUCT
{
char buf[64];
snprintf(buf, sizeof buf, "zero_words (count = %" PRIu64 ") {", cnt);
BLOCK_COMMENT(buf);
}
#endif
if (cnt >= 16) {
uint64_t loops = cnt/16;
if (loops > 1) {
mov(rscratch2, loops - 1);
}
{
Label loop;
bind(loop);
for (int i = 0; i < 16; i += 2) {
stp(zr, zr, Address(base, i * BytesPerWord));
}
add(base, base, 16 * BytesPerWord);
if (loops > 1) {
subs(rscratch2, rscratch2, 1);
br(GE, loop);
}
}
}
cnt %= 16;
int i = cnt & 1; // store any odd word to start
if (i) str(zr, Address(base));
for (; i < (int)cnt; i += 2) {
stp(zr, zr, Address(base, i * wordSize));
}
BLOCK_COMMENT("} zero_words");
result = pc();
} else {
mov(r10, base); mov(r11, cnt);
result = zero_words(r10, r11);
}
return result;
}
// Zero blocks of memory by using DC ZVA.
//
// Aligns the base address first sufficiently for DC ZVA, then uses
// DC ZVA repeatedly for every full block. cnt is the size to be
// zeroed in HeapWords. Returns the count of words left to be zeroed
// in cnt.
//
// NOTE: This is intended to be used in the zero_blocks() stub. If
// you want to use it elsewhere, note that cnt must be >= 2*zva_length.
void MacroAssembler::zero_dcache_blocks(Register base, Register cnt) {
Register tmp = rscratch1;
Register tmp2 = rscratch2;
int zva_length = VM_Version::zva_length();
Label initial_table_end, loop_zva;
Label fini;
// Base must be 16 byte aligned. If not just return and let caller handle it
tst(base, 0x0f);
br(Assembler::NE, fini);
// Align base with ZVA length.
neg(tmp, base);
andr(tmp, tmp, zva_length - 1);
// tmp: the number of bytes to be filled to align the base with ZVA length.
add(base, base, tmp);
sub(cnt, cnt, tmp, Assembler::ASR, 3);
adr(tmp2, initial_table_end);
sub(tmp2, tmp2, tmp, Assembler::LSR, 2);
br(tmp2);
for (int i = -zva_length + 16; i < 0; i += 16)
stp(zr, zr, Address(base, i));
bind(initial_table_end);
sub(cnt, cnt, zva_length >> 3);
bind(loop_zva);
dc(Assembler::ZVA, base);
subs(cnt, cnt, zva_length >> 3);
add(base, base, zva_length);
br(Assembler::GE, loop_zva);
add(cnt, cnt, zva_length >> 3); // count not zeroed by DC ZVA
bind(fini);
}
// base: Address of a buffer to be filled, 8 bytes aligned.
// cnt: Count in 8-byte unit.
// value: Value to be filled with.
// base will point to the end of the buffer after filling.
void MacroAssembler::fill_words(Register base, Register cnt, Register value)
{
// Algorithm:
//
// if (cnt == 0) {
// return;
// }
// if ((p & 8) != 0) {
// *p++ = v;
// }
//
// scratch1 = cnt & 14;
// cnt -= scratch1;
// p += scratch1;
// switch (scratch1 / 2) {
// do {
// cnt -= 16;
// p[-16] = v;
// p[-15] = v;
// case 7:
// p[-14] = v;
// p[-13] = v;
// case 6:
// p[-12] = v;
// p[-11] = v;
// // ...
// case 1:
// p[-2] = v;
// p[-1] = v;
// case 0:
// p += 16;
// } while (cnt);
// }
// if ((cnt & 1) == 1) {
// *p++ = v;
// }
assert_different_registers(base, cnt, value, rscratch1, rscratch2);
Label fini, skip, entry, loop;
const int unroll = 8; // Number of stp instructions we'll unroll
cbz(cnt, fini);
tbz(base, 3, skip);
str(value, Address(post(base, 8)));
sub(cnt, cnt, 1);
bind(skip);
andr(rscratch1, cnt, (unroll-1) * 2);
sub(cnt, cnt, rscratch1);
add(base, base, rscratch1, Assembler::LSL, 3);
adr(rscratch2, entry);
sub(rscratch2, rscratch2, rscratch1, Assembler::LSL, 1);
br(rscratch2);
bind(loop);
add(base, base, unroll * 16);
for (int i = -unroll; i < 0; i++)
stp(value, value, Address(base, i * 16));
bind(entry);
subs(cnt, cnt, unroll * 2);
br(Assembler::GE, loop);
tbz(cnt, 0, fini);
str(value, Address(post(base, 8)));
bind(fini);
}
// Intrinsic for
//
// - sun/nio/cs/ISO_8859_1$Encoder.implEncodeISOArray
// return the number of characters copied.
// - java/lang/StringUTF16.compress
// return index of non-latin1 character if copy fails, otherwise 'len'.
//
// This version always returns the number of characters copied, and does not
// clobber the 'len' register. A successful copy will complete with the post-
// condition: 'res' == 'len', while an unsuccessful copy will exit with the
// post-condition: 0 <= 'res' < 'len'.
//
// NOTE: Attempts to use 'ld2' (and 'umaxv' in the ISO part) has proven to
// degrade performance (on Ampere Altra - Neoverse N1), to an extent
// beyond the acceptable, even though the footprint would be smaller.
// Using 'umaxv' in the ASCII-case comes with a small penalty but does
// avoid additional bloat.
//
// Clobbers: src, dst, res, rscratch1, rscratch2, rflags
void MacroAssembler::encode_iso_array(Register src, Register dst,
Register len, Register res, bool ascii,
FloatRegister vtmp0, FloatRegister vtmp1,
FloatRegister vtmp2, FloatRegister vtmp3,
FloatRegister vtmp4, FloatRegister vtmp5)
{
Register cnt = res;
Register max = rscratch1;
Register chk = rscratch2;
prfm(Address(src), PLDL1STRM);
movw(cnt, len);
#define ASCII(insn) do { if (ascii) { insn; } } while (0)
Label LOOP_32, DONE_32, FAIL_32;
BIND(LOOP_32);
{
cmpw(cnt, 32);
br(LT, DONE_32);
ld1(vtmp0, vtmp1, vtmp2, vtmp3, T8H, Address(post(src, 64)));
// Extract lower bytes.
FloatRegister vlo0 = vtmp4;
FloatRegister vlo1 = vtmp5;
uzp1(vlo0, T16B, vtmp0, vtmp1);
uzp1(vlo1, T16B, vtmp2, vtmp3);
// Merge bits...
orr(vtmp0, T16B, vtmp0, vtmp1);
orr(vtmp2, T16B, vtmp2, vtmp3);
// Extract merged upper bytes.
FloatRegister vhix = vtmp0;
uzp2(vhix, T16B, vtmp0, vtmp2);
// ISO-check on hi-parts (all zero).
// ASCII-check on lo-parts (no sign).
FloatRegister vlox = vtmp1; // Merge lower bytes.
ASCII(orr(vlox, T16B, vlo0, vlo1));
umov(chk, vhix, D, 1); ASCII(cm(LT, vlox, T16B, vlox));
fmovd(max, vhix); ASCII(umaxv(vlox, T16B, vlox));
orr(chk, chk, max); ASCII(umov(max, vlox, B, 0));
ASCII(orr(chk, chk, max));
cbnz(chk, FAIL_32);
subw(cnt, cnt, 32);
st1(vlo0, vlo1, T16B, Address(post(dst, 32)));
b(LOOP_32);
}
BIND(FAIL_32);
sub(src, src, 64);
BIND(DONE_32);
Label LOOP_8, SKIP_8;
BIND(LOOP_8);
{
cmpw(cnt, 8);
br(LT, SKIP_8);
FloatRegister vhi = vtmp0;
FloatRegister vlo = vtmp1;
ld1(vtmp3, T8H, src);
uzp1(vlo, T16B, vtmp3, vtmp3);
uzp2(vhi, T16B, vtmp3, vtmp3);
// ISO-check on hi-parts (all zero).
// ASCII-check on lo-parts (no sign).
ASCII(cm(LT, vtmp2, T16B, vlo));
fmovd(chk, vhi); ASCII(umaxv(vtmp2, T16B, vtmp2));
ASCII(umov(max, vtmp2, B, 0));
ASCII(orr(chk, chk, max));
cbnz(chk, SKIP_8);
strd(vlo, Address(post(dst, 8)));
subw(cnt, cnt, 8);
add(src, src, 16);
b(LOOP_8);
}
BIND(SKIP_8);
#undef ASCII
Label LOOP, DONE;
cbz(cnt, DONE);
BIND(LOOP);
{
Register chr = rscratch1;
ldrh(chr, Address(post(src, 2)));
tst(chr, ascii ? 0xff80 : 0xff00);
br(NE, DONE);
strb(chr, Address(post(dst, 1)));
subs(cnt, cnt, 1);
br(GT, LOOP);
}
BIND(DONE);
// Return index where we stopped.
subw(res, len, cnt);
}
// Inflate byte[] array to char[].
// Clobbers: src, dst, len, rflags, rscratch1, v0-v6
address MacroAssembler::byte_array_inflate(Register src, Register dst, Register len,
FloatRegister vtmp1, FloatRegister vtmp2,
FloatRegister vtmp3, Register tmp4) {
Label big, done, after_init, to_stub;
assert_different_registers(src, dst, len, tmp4, rscratch1);
fmovd(vtmp1, 0.0);
lsrw(tmp4, len, 3);
bind(after_init);
cbnzw(tmp4, big);
// Short string: less than 8 bytes.
{
Label loop, tiny;
cmpw(len, 4);
br(LT, tiny);
// Use SIMD to do 4 bytes.
ldrs(vtmp2, post(src, 4));
zip1(vtmp3, T8B, vtmp2, vtmp1);
subw(len, len, 4);
strd(vtmp3, post(dst, 8));
cbzw(len, done);
// Do the remaining bytes by steam.
bind(loop);
ldrb(tmp4, post(src, 1));
strh(tmp4, post(dst, 2));
subw(len, len, 1);
bind(tiny);
cbnz(len, loop);
b(done);
}
if (SoftwarePrefetchHintDistance >= 0) {
bind(to_stub);
RuntimeAddress stub = RuntimeAddress(StubRoutines::aarch64::large_byte_array_inflate());
assert(stub.target() != nullptr, "large_byte_array_inflate stub has not been generated");
address tpc = trampoline_call(stub);
if (tpc == nullptr) {
DEBUG_ONLY(reset_labels(big, done));
postcond(pc() == badAddress);
return nullptr;
}
b(after_init);
}
// Unpack the bytes 8 at a time.
bind(big);
{
Label loop, around, loop_last, loop_start;
if (SoftwarePrefetchHintDistance >= 0) {
const int large_loop_threshold = (64 + 16)/8;
ldrd(vtmp2, post(src, 8));
andw(len, len, 7);
cmp(tmp4, (u1)large_loop_threshold);
br(GE, to_stub);
b(loop_start);
bind(loop);
ldrd(vtmp2, post(src, 8));
bind(loop_start);
subs(tmp4, tmp4, 1);
br(EQ, loop_last);
zip1(vtmp2, T16B, vtmp2, vtmp1);
ldrd(vtmp3, post(src, 8));
st1(vtmp2, T8H, post(dst, 16));
subs(tmp4, tmp4, 1);
zip1(vtmp3, T16B, vtmp3, vtmp1);
st1(vtmp3, T8H, post(dst, 16));
br(NE, loop);
b(around);
bind(loop_last);
zip1(vtmp2, T16B, vtmp2, vtmp1);
st1(vtmp2, T8H, post(dst, 16));
bind(around);
cbz(len, done);
} else {
andw(len, len, 7);
bind(loop);
ldrd(vtmp2, post(src, 8));
sub(tmp4, tmp4, 1);
zip1(vtmp3, T16B, vtmp2, vtmp1);
st1(vtmp3, T8H, post(dst, 16));
cbnz(tmp4, loop);
}
}
// Do the tail of up to 8 bytes.
add(src, src, len);
ldrd(vtmp3, Address(src, -8));
add(dst, dst, len, ext::uxtw, 1);
zip1(vtmp3, T16B, vtmp3, vtmp1);
strq(vtmp3, Address(dst, -16));
bind(done);
postcond(pc() != badAddress);
return pc();
}
// Compress char[] array to byte[].
// Intrinsic for java.lang.StringUTF16.compress(char[] src, int srcOff, byte[] dst, int dstOff, int len)
// Return the array length if every element in array can be encoded,
// otherwise, the index of first non-latin1 (> 0xff) character.
void MacroAssembler::char_array_compress(Register src, Register dst, Register len,
Register res,
FloatRegister tmp0, FloatRegister tmp1,
FloatRegister tmp2, FloatRegister tmp3,
FloatRegister tmp4, FloatRegister tmp5) {
encode_iso_array(src, dst, len, res, false, tmp0, tmp1, tmp2, tmp3, tmp4, tmp5);
}
// java.math.round(double a)
// Returns the closest long to the argument, with ties rounding to
// positive infinity. This requires some fiddling for corner
// cases. We take care to avoid double rounding in e.g. (jlong)(a + 0.5).
void MacroAssembler::java_round_double(Register dst, FloatRegister src,
FloatRegister ftmp) {
Label DONE;
BLOCK_COMMENT("java_round_double: { ");
fmovd(rscratch1, src);
// Use RoundToNearestTiesAway unless src small and -ve.
fcvtasd(dst, src);
// Test if src >= 0 || abs(src) >= 0x1.0p52
eor(rscratch1, rscratch1, UCONST64(1) << 63); // flip sign bit
mov(rscratch2, julong_cast(0x1.0p52));
cmp(rscratch1, rscratch2);
br(HS, DONE); {
// src < 0 && abs(src) < 0x1.0p52
// src may have a fractional part, so add 0.5
fmovd(ftmp, 0.5);
faddd(ftmp, src, ftmp);
// Convert double to jlong, use RoundTowardsNegative
fcvtmsd(dst, ftmp);
}
bind(DONE);
BLOCK_COMMENT("} java_round_double");
}
void MacroAssembler::java_round_float(Register dst, FloatRegister src,
FloatRegister ftmp) {
Label DONE;
BLOCK_COMMENT("java_round_float: { ");
fmovs(rscratch1, src);
// Use RoundToNearestTiesAway unless src small and -ve.
fcvtassw(dst, src);
// Test if src >= 0 || abs(src) >= 0x1.0p23
eor(rscratch1, rscratch1, 0x80000000); // flip sign bit
mov(rscratch2, jint_cast(0x1.0p23f));
cmp(rscratch1, rscratch2);
br(HS, DONE); {
// src < 0 && |src| < 0x1.0p23
// src may have a fractional part, so add 0.5
fmovs(ftmp, 0.5f);
fadds(ftmp, src, ftmp);
// Convert float to jint, use RoundTowardsNegative
fcvtmssw(dst, ftmp);
}
bind(DONE);
BLOCK_COMMENT("} java_round_float");
}
// get_thread() can be called anywhere inside generated code so we
// need to save whatever non-callee save context might get clobbered
// by the call to JavaThread::aarch64_get_thread_helper() or, indeed,
// the call setup code.
//
// On Linux, aarch64_get_thread_helper() clobbers only r0, r1, and flags.
// On other systems, the helper is a usual C function.
//
void MacroAssembler::get_thread(Register dst) {
RegSet saved_regs =
LINUX_ONLY(RegSet::range(r0, r1) + lr - dst)
NOT_LINUX (RegSet::range(r0, r17) + lr - dst);
protect_return_address();
push(saved_regs, sp);
mov(lr, ExternalAddress(CAST_FROM_FN_PTR(address, JavaThread::aarch64_get_thread_helper)));
blr(lr);
if (dst != c_rarg0) {
mov(dst, c_rarg0);
}
pop(saved_regs, sp);
authenticate_return_address();
}
void MacroAssembler::cache_wb(Address line) {
assert(line.getMode() == Address::base_plus_offset, "mode should be base_plus_offset");
assert(line.index() == noreg, "index should be noreg");
assert(line.offset() == 0, "offset should be 0");
// would like to assert this
// assert(line._ext.shift == 0, "shift should be zero");
if (VM_Version::supports_dcpop()) {
// writeback using clear virtual address to point of persistence
dc(Assembler::CVAP, line.base());
} else {
// no need to generate anything as Unsafe.writebackMemory should
// never invoke this stub
}
}
void MacroAssembler::cache_wbsync(bool is_pre) {
// we only need a barrier post sync
if (!is_pre) {
membar(Assembler::AnyAny);
}
}
void MacroAssembler::verify_sve_vector_length(Register tmp) {
if (!UseSVE || VM_Version::get_max_supported_sve_vector_length() == FloatRegister::sve_vl_min) {
return;
}
// Make sure that native code does not change SVE vector length.
Label verify_ok;
movw(tmp, zr);
sve_inc(tmp, B);
subsw(zr, tmp, VM_Version::get_initial_sve_vector_length());
br(EQ, verify_ok);
stop("Error: SVE vector length has changed since jvm startup");
bind(verify_ok);
}
void MacroAssembler::verify_ptrue() {
Label verify_ok;
if (!UseSVE) {
return;
}
sve_cntp(rscratch1, B, ptrue, ptrue); // get true elements count.
sve_dec(rscratch1, B);
cbz(rscratch1, verify_ok);
stop("Error: the preserved predicate register (p7) elements are not all true");
bind(verify_ok);
}
void MacroAssembler::safepoint_isb() {
isb();
#ifndef PRODUCT
if (VerifyCrossModifyFence) {
// Clear the thread state.
strb(zr, Address(rthread, in_bytes(JavaThread::requires_cross_modify_fence_offset())));
}
#endif
}
#ifndef PRODUCT
void MacroAssembler::verify_cross_modify_fence_not_required() {
if (VerifyCrossModifyFence) {
// Check if thread needs a cross modify fence.
ldrb(rscratch1, Address(rthread, in_bytes(JavaThread::requires_cross_modify_fence_offset())));
Label fence_not_required;
cbz(rscratch1, fence_not_required);
// If it does then fail.
lea(rscratch1, RuntimeAddress(CAST_FROM_FN_PTR(address, JavaThread::verify_cross_modify_fence_failure)));
mov(c_rarg0, rthread);
blr(rscratch1);
bind(fence_not_required);
}
}
#endif
void MacroAssembler::spin_wait() {
for (int i = 0; i < VM_Version::spin_wait_desc().inst_count(); ++i) {
switch (VM_Version::spin_wait_desc().inst()) {
case SpinWait::NOP:
nop();
break;
case SpinWait::ISB:
isb();
break;
case SpinWait::YIELD:
yield();
break;
default:
ShouldNotReachHere();
}
}
}
// Stack frame creation/removal
void MacroAssembler::enter(bool strip_ret_addr) {
if (strip_ret_addr) {
// Addresses can only be signed once. If there are multiple nested frames being created
// in the same function, then the return address needs stripping first.
strip_return_address();
}
protect_return_address();
stp(rfp, lr, Address(pre(sp, -2 * wordSize)));
mov(rfp, sp);
}
void MacroAssembler::leave() {
mov(sp, rfp);
ldp(rfp, lr, Address(post(sp, 2 * wordSize)));
authenticate_return_address();
}
// ROP Protection
// Use the AArch64 PAC feature to add ROP protection for generated code. Use whenever creating/
// destroying stack frames or whenever directly loading/storing the LR to memory.
// If ROP protection is not set then these functions are no-ops.
// For more details on PAC see pauth_aarch64.hpp.
// Sign the LR. Use during construction of a stack frame, before storing the LR to memory.
// Uses value zero as the modifier.
//
void MacroAssembler::protect_return_address() {
if (VM_Version::use_rop_protection()) {
check_return_address();
paciaz();
}
}
// Sign the return value in the given register. Use before updating the LR in the existing stack
// frame for the current function.
// Uses value zero as the modifier.
//
void MacroAssembler::protect_return_address(Register return_reg) {
if (VM_Version::use_rop_protection()) {
check_return_address(return_reg);
paciza(return_reg);
}
}
// Authenticate the LR. Use before function return, after restoring FP and loading LR from memory.
// Uses value zero as the modifier.
//
void MacroAssembler::authenticate_return_address() {
if (VM_Version::use_rop_protection()) {
autiaz();
check_return_address();
}
}
// Authenticate the return value in the given register. Use before updating the LR in the existing
// stack frame for the current function.
// Uses value zero as the modifier.
//
void MacroAssembler::authenticate_return_address(Register return_reg) {
if (VM_Version::use_rop_protection()) {
autiza(return_reg);
check_return_address(return_reg);
}
}
// Strip any PAC data from LR without performing any authentication. Use with caution - only if
// there is no guaranteed way of authenticating the LR.
//
void MacroAssembler::strip_return_address() {
if (VM_Version::use_rop_protection()) {
xpaclri();
}
}
#ifndef PRODUCT
// PAC failures can be difficult to debug. After an authentication failure, a segfault will only
// occur when the pointer is used - ie when the program returns to the invalid LR. At this point
// it is difficult to debug back to the callee function.
// This function simply loads from the address in the given register.
// Use directly after authentication to catch authentication failures.
// Also use before signing to check that the pointer is valid and hasn't already been signed.
//
void MacroAssembler::check_return_address(Register return_reg) {
if (VM_Version::use_rop_protection()) {
ldr(zr, Address(return_reg));
}
}
#endif
// The java_calling_convention describes stack locations as ideal slots on
// a frame with no abi restrictions. Since we must observe abi restrictions
// (like the placement of the register window) the slots must be biased by
// the following value.
static int reg2offset_in(VMReg r) {
// Account for saved rfp and lr
// This should really be in_preserve_stack_slots
return (r->reg2stack() + 4) * VMRegImpl::stack_slot_size;
}
static int reg2offset_out(VMReg r) {
return (r->reg2stack() + SharedRuntime::out_preserve_stack_slots()) * VMRegImpl::stack_slot_size;
}
// On 64bit we will store integer like items to the stack as
// 64bits items (AArch64 ABI) even though java would only store
// 32bits for a parameter. On 32bit it will simply be 32bits
// So this routine will do 32->32 on 32bit and 32->64 on 64bit
void MacroAssembler::move32_64(VMRegPair src, VMRegPair dst, Register tmp) {
if (src.first()->is_stack()) {
if (dst.first()->is_stack()) {
// stack to stack
ldr(tmp, Address(rfp, reg2offset_in(src.first())));
str(tmp, Address(sp, reg2offset_out(dst.first())));
} else {
// stack to reg
ldrsw(dst.first()->as_Register(), Address(rfp, reg2offset_in(src.first())));
}
} else if (dst.first()->is_stack()) {
// reg to stack
str(src.first()->as_Register(), Address(sp, reg2offset_out(dst.first())));
} else {
if (dst.first() != src.first()) {
sxtw(dst.first()->as_Register(), src.first()->as_Register());
}
}
}
// An oop arg. Must pass a handle not the oop itself
void MacroAssembler::object_move(
OopMap* map,
int oop_handle_offset,
int framesize_in_slots,
VMRegPair src,
VMRegPair dst,
bool is_receiver,
int* receiver_offset) {
// must pass a handle. First figure out the location we use as a handle
Register rHandle = dst.first()->is_stack() ? rscratch2 : dst.first()->as_Register();
// See if oop is null if it is we need no handle
if (src.first()->is_stack()) {
// Oop is already on the stack as an argument
int offset_in_older_frame = src.first()->reg2stack() + SharedRuntime::out_preserve_stack_slots();
map->set_oop(VMRegImpl::stack2reg(offset_in_older_frame + framesize_in_slots));
if (is_receiver) {
*receiver_offset = (offset_in_older_frame + framesize_in_slots) * VMRegImpl::stack_slot_size;
}
ldr(rscratch1, Address(rfp, reg2offset_in(src.first())));
lea(rHandle, Address(rfp, reg2offset_in(src.first())));
// conditionally move a null
cmp(rscratch1, zr);
csel(rHandle, zr, rHandle, Assembler::EQ);
} else {
// Oop is in an a register we must store it to the space we reserve
// on the stack for oop_handles and pass a handle if oop is non-null
const Register rOop = src.first()->as_Register();
int oop_slot;
if (rOop == j_rarg0)
oop_slot = 0;
else if (rOop == j_rarg1)
oop_slot = 1;
else if (rOop == j_rarg2)
oop_slot = 2;
else if (rOop == j_rarg3)
oop_slot = 3;
else if (rOop == j_rarg4)
oop_slot = 4;
else if (rOop == j_rarg5)
oop_slot = 5;
else if (rOop == j_rarg6)
oop_slot = 6;
else {
assert(rOop == j_rarg7, "wrong register");
oop_slot = 7;
}
oop_slot = oop_slot * VMRegImpl::slots_per_word + oop_handle_offset;
int offset = oop_slot*VMRegImpl::stack_slot_size;
map->set_oop(VMRegImpl::stack2reg(oop_slot));
// Store oop in handle area, may be null
str(rOop, Address(sp, offset));
if (is_receiver) {
*receiver_offset = offset;
}
cmp(rOop, zr);
lea(rHandle, Address(sp, offset));
// conditionally move a null
csel(rHandle, zr, rHandle, Assembler::EQ);
}
// If arg is on the stack then place it otherwise it is already in correct reg.
if (dst.first()->is_stack()) {
str(rHandle, Address(sp, reg2offset_out(dst.first())));
}
}
// A float arg may have to do float reg int reg conversion
void MacroAssembler::float_move(VMRegPair src, VMRegPair dst, Register tmp) {
if (src.first()->is_stack()) {
if (dst.first()->is_stack()) {
ldrw(tmp, Address(rfp, reg2offset_in(src.first())));
strw(tmp, Address(sp, reg2offset_out(dst.first())));
} else {
ldrs(dst.first()->as_FloatRegister(), Address(rfp, reg2offset_in(src.first())));
}
} else if (src.first() != dst.first()) {
if (src.is_single_phys_reg() && dst.is_single_phys_reg())
fmovs(dst.first()->as_FloatRegister(), src.first()->as_FloatRegister());
else
strs(src.first()->as_FloatRegister(), Address(sp, reg2offset_out(dst.first())));
}
}
// A long move
void MacroAssembler::long_move(VMRegPair src, VMRegPair dst, Register tmp) {
if (src.first()->is_stack()) {
if (dst.first()->is_stack()) {
// stack to stack
ldr(tmp, Address(rfp, reg2offset_in(src.first())));
str(tmp, Address(sp, reg2offset_out(dst.first())));
} else {
// stack to reg
ldr(dst.first()->as_Register(), Address(rfp, reg2offset_in(src.first())));
}
} else if (dst.first()->is_stack()) {
// reg to stack
// Do we really have to sign extend???
// __ movslq(src.first()->as_Register(), src.first()->as_Register());
str(src.first()->as_Register(), Address(sp, reg2offset_out(dst.first())));
} else {
if (dst.first() != src.first()) {
mov(dst.first()->as_Register(), src.first()->as_Register());
}
}
}
// A double move
void MacroAssembler::double_move(VMRegPair src, VMRegPair dst, Register tmp) {
if (src.first()->is_stack()) {
if (dst.first()->is_stack()) {
ldr(tmp, Address(rfp, reg2offset_in(src.first())));
str(tmp, Address(sp, reg2offset_out(dst.first())));
} else {
ldrd(dst.first()->as_FloatRegister(), Address(rfp, reg2offset_in(src.first())));
}
} else if (src.first() != dst.first()) {
if (src.is_single_phys_reg() && dst.is_single_phys_reg())
fmovd(dst.first()->as_FloatRegister(), src.first()->as_FloatRegister());
else
strd(src.first()->as_FloatRegister(), Address(sp, reg2offset_out(dst.first())));
}
}
// Implements lightweight-locking.
//
// - obj: the object to be locked
// - t1, t2, t3: temporary registers, will be destroyed
// - slow: branched to if locking fails, absolute offset may larger than 32KB (imm14 encoding).
void MacroAssembler::lightweight_lock(Register basic_lock, Register obj, Register t1, Register t2, Register t3, Label& slow) {
assert(LockingMode == LM_LIGHTWEIGHT, "only used with new lightweight locking");
assert_different_registers(basic_lock, obj, t1, t2, t3, rscratch1);
Label push;
const Register top = t1;
const Register mark = t2;
const Register t = t3;
// Preload the markWord. It is important that this is the first
// instruction emitted as it is part of C1's null check semantics.
ldr(mark, Address(obj, oopDesc::mark_offset_in_bytes()));
if (UseObjectMonitorTable) {
// Clear cache in case fast locking succeeds or we need to take the slow-path.
str(zr, Address(basic_lock, BasicObjectLock::lock_offset() + in_ByteSize((BasicLock::object_monitor_cache_offset_in_bytes()))));
}
if (DiagnoseSyncOnValueBasedClasses != 0) {
load_klass(t1, obj);
ldrb(t1, Address(t1, Klass::misc_flags_offset()));
tst(t1, KlassFlags::_misc_is_value_based_class);
br(Assembler::NE, slow);
}
// Check if the lock-stack is full.
ldrw(top, Address(rthread, JavaThread::lock_stack_top_offset()));
cmpw(top, (unsigned)LockStack::end_offset());
br(Assembler::GE, slow);
// Check for recursion.
subw(t, top, oopSize);
ldr(t, Address(rthread, t));
cmp(obj, t);
br(Assembler::EQ, push);
// Check header for monitor (0b10).
tst(mark, markWord::monitor_value);
br(Assembler::NE, slow);
// Try to lock. Transition lock bits 0b01 => 0b00
assert(oopDesc::mark_offset_in_bytes() == 0, "required to avoid lea");
orr(mark, mark, markWord::unlocked_value);
eor(t, mark, markWord::unlocked_value);
cmpxchg(/*addr*/ obj, /*expected*/ mark, /*new*/ t, Assembler::xword,
/*acquire*/ true, /*release*/ false, /*weak*/ false, noreg);
br(Assembler::NE, slow);
bind(push);
// After successful lock, push object on lock-stack.
str(obj, Address(rthread, top));
addw(top, top, oopSize);
strw(top, Address(rthread, JavaThread::lock_stack_top_offset()));
}
// Implements lightweight-unlocking.
//
// - obj: the object to be unlocked
// - t1, t2, t3: temporary registers
// - slow: branched to if unlocking fails, absolute offset may larger than 32KB (imm14 encoding).
void MacroAssembler::lightweight_unlock(Register obj, Register t1, Register t2, Register t3, Label& slow) {
assert(LockingMode == LM_LIGHTWEIGHT, "only used with new lightweight locking");
// cmpxchg clobbers rscratch1.
assert_different_registers(obj, t1, t2, t3, rscratch1);
#ifdef ASSERT
{
// Check for lock-stack underflow.
Label stack_ok;
ldrw(t1, Address(rthread, JavaThread::lock_stack_top_offset()));
cmpw(t1, (unsigned)LockStack::start_offset());
br(Assembler::GE, stack_ok);
STOP("Lock-stack underflow");
bind(stack_ok);
}
#endif
Label unlocked, push_and_slow;
const Register top = t1;
const Register mark = t2;
const Register t = t3;
// Check if obj is top of lock-stack.
ldrw(top, Address(rthread, JavaThread::lock_stack_top_offset()));
subw(top, top, oopSize);
ldr(t, Address(rthread, top));
cmp(obj, t);
br(Assembler::NE, slow);
// Pop lock-stack.
DEBUG_ONLY(str(zr, Address(rthread, top));)
strw(top, Address(rthread, JavaThread::lock_stack_top_offset()));
// Check if recursive.
subw(t, top, oopSize);
ldr(t, Address(rthread, t));
cmp(obj, t);
br(Assembler::EQ, unlocked);
// Not recursive. Check header for monitor (0b10).
ldr(mark, Address(obj, oopDesc::mark_offset_in_bytes()));
tbnz(mark, log2i_exact(markWord::monitor_value), push_and_slow);
#ifdef ASSERT
// Check header not unlocked (0b01).
Label not_unlocked;
tbz(mark, log2i_exact(markWord::unlocked_value), not_unlocked);
stop("lightweight_unlock already unlocked");
bind(not_unlocked);
#endif
// Try to unlock. Transition lock bits 0b00 => 0b01
assert(oopDesc::mark_offset_in_bytes() == 0, "required to avoid lea");
orr(t, mark, markWord::unlocked_value);
cmpxchg(obj, mark, t, Assembler::xword,
/*acquire*/ false, /*release*/ true, /*weak*/ false, noreg);
br(Assembler::EQ, unlocked);
bind(push_and_slow);
// Restore lock-stack and handle the unlock in runtime.
DEBUG_ONLY(str(obj, Address(rthread, top));)
addw(top, top, oopSize);
strw(top, Address(rthread, JavaThread::lock_stack_top_offset()));
b(slow);
bind(unlocked);
}