| /* Set up a context to call a function. |
| Copyright (C) 2002-2018 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| |
| The GNU C Library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Lesser General Public |
| License as published by the Free Software Foundation; either |
| version 2.1 of the License, or (at your option) any later version. |
| |
| The GNU C Library 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 |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public |
| License along with the GNU C Library; if not, see |
| <http://www.gnu.org/licenses/>. */ |
| |
| #include <sysdep.h> |
| #include <shlib-compat.h> |
| |
| #define __ASSEMBLY__ |
| #include <asm/ptrace.h> |
| #include "ucontext_i.h" |
| |
| ENTRY(__makecontext) |
| /* Set up the first 7 args to the function in its registers */ |
| lwz r11,_UC_REGS_PTR(r3) |
| stw r6,_UC_GREGS+(PT_R3*4)(r11) |
| stw r7,_UC_GREGS+(PT_R4*4)(r11) |
| stw r8,_UC_GREGS+(PT_R5*4)(r11) |
| stw r9,_UC_GREGS+(PT_R6*4)(r11) |
| stw r10,_UC_GREGS+(PT_R7*4)(r11) |
| lwz r8,8(r1) |
| lwz r9,12(r1) |
| stw r8,_UC_GREGS+(PT_R8*4)(r11) |
| stw r9,_UC_GREGS+(PT_R9*4)(r11) |
| |
| /* Set the NIP to the start of the function */ |
| stw r4,_UC_GREGS+(PT_NIP*4)(r11) |
| |
| /* Set the function's r31 to ucp->uc_link for the exitcode below. */ |
| lwz r7,_UC_LINK(r3) |
| stw r7,_UC_GREGS+(PT_R31*4)(r11) |
| |
| /* Set the function's LR to point to the exitcode below. */ |
| #ifdef PIC |
| mflr r0 |
| cfi_register(lr,r0) |
| /* Use this conditional form of branch and link to avoid destroying |
| the cpu link stack used to predict blr return addresses. */ |
| bcl 20,31,1f |
| 1: mflr r6 |
| addi r6,r6,L(exitcode)-1b |
| mtlr r0 |
| cfi_same_value (lr) |
| #else |
| lis r6,L(exitcode)@ha |
| addi r6,r6,L(exitcode)@l |
| #endif |
| stw r6,_UC_GREGS+(PT_LNK*4)(r11) |
| |
| /* |
| * Set up the stack frame for the function. |
| * If we have more than 5 args to the function (8 args to makecontext), |
| * there will be some arguments on the stack which have to end up |
| * in registers. If there are more than 8 args to the function, |
| * we have to copy (argc - 8) args from our stack to the functions' |
| * stack (and allow space for them in the frame). |
| */ |
| lwz r4,_UC_STACK_SP(r3) |
| lwz r8,_UC_STACK_SIZE(r3) |
| add r4,r4,r8 |
| rlwinm r4,r4,0,0,27 /* round down to 16-byte boundary */ |
| addi r7,r4,-16 /* stack frame for fn's caller */ |
| cmpwi r5,8 |
| blt 2f /* less than 8 args is easy */ |
| lwz r10,16(r1) |
| stw r10,_UC_GREGS+(PT_R10*4)(r11) |
| beq 2f /* if exactly 8 args */ |
| subi r9,r5,3 |
| subi r5,r5,8 |
| rlwinm r9,r9,2,0,27 |
| subf r7,r9,r4 |
| mtctr r5 /* copy the 9th and following args */ |
| addi r6,r1,16 |
| addi r8,r7,4 |
| 3: lwzu r10,4(r6) |
| stwu r10,4(r8) |
| bdnz 3b |
| 2: stw r7,_UC_GREGS+(PT_R1*4)(r11) |
| li r6,0 |
| stw r6,0(r7) |
| |
| blr |
| |
| cfi_endproc |
| nop |
| /* |
| * If the function returns, it comes here. We put ucp->uc_link in |
| * r31, which is a callee-saved register. We have to continue with |
| * the context that r31 points to, or exit if it is 0. |
| */ |
| L(exitcode): |
| mr. r3,r31 |
| beq 4f |
| bl __setcontext@local |
| 4: bl HIDDEN_JUMPTARGET(exit) |
| b 4b |
| |
| cfi_startproc |
| END(__makecontext) |
| |
| versioned_symbol (libc, __makecontext, makecontext, GLIBC_2_3_4) |
| |
| #if SHLIB_COMPAT (libc, GLIBC_2_3_3, GLIBC_2_3_4) |
| |
| compat_text_section |
| ENTRY(__novec_makecontext) |
| /* Set up the first 7 args to the function in its registers */ |
| addi r11,r3,_UC_REG_SPACE |
| stw r11,_UC_REGS_PTR(r3) |
| stw r6,_UC_GREGS+(PT_R3*4)(r11) |
| stw r7,_UC_GREGS+(PT_R4*4)(r11) |
| stw r8,_UC_GREGS+(PT_R5*4)(r11) |
| stw r9,_UC_GREGS+(PT_R6*4)(r11) |
| stw r10,_UC_GREGS+(PT_R7*4)(r11) |
| lwz r8,8(r1) |
| lwz r9,12(r1) |
| stw r8,_UC_GREGS+(PT_R8*4)(r11) |
| stw r9,_UC_GREGS+(PT_R9*4)(r11) |
| |
| /* Set the NIP to the start of the function */ |
| stw r4,_UC_GREGS+(PT_NIP*4)(r11) |
| |
| /* Set the function's r31 to ucp->uc_link for the exitcode below. */ |
| lwz r7,_UC_LINK(r3) |
| stw r7,_UC_GREGS+(PT_R31*4)(r11) |
| |
| /* Set the function's LR to point to the exitcode below. */ |
| #ifdef PIC |
| mflr r0 |
| cfi_register(lr,r0) |
| /* Use this conditional form of branch and link to avoid destroying |
| the cpu link stack used to predict blr return addresses. */ |
| bcl 20,31,1f |
| 1: mflr r6 |
| addi r6,r6,L(novec_exitcode)-1b |
| mtlr r0 |
| cfi_same_value (lr) |
| #else |
| lis r6,L(novec_exitcode)@ha |
| addi r6,r6,L(novec_exitcode)@l |
| #endif |
| stw r6,_UC_GREGS+(PT_LNK*4)(r11) |
| |
| /* |
| * Set up the stack frame for the function. |
| * If we have more than 5 args to the function (8 args to makecontext), |
| * there will be some arguments on the stack which have to end up |
| * in registers. If there are more than 8 args to the function, |
| * we have to copy (argc - 8) args from our stack to the functions' |
| * stack (and allow space for them in the frame). |
| */ |
| lwz r4,_UC_STACK_SP(r3) |
| lwz r8,_UC_STACK_SIZE(r3) |
| add r4,r4,r8 |
| rlwinm r4,r4,0,0,27 /* round down to 16-byte boundary */ |
| addi r7,r4,-16 /* stack frame for fn's caller */ |
| cmpwi r5,8 |
| blt 2f /* less than 8 args is easy */ |
| lwz r10,16(r1) |
| stw r10,_UC_GREGS+(PT_R10*4)(r11) |
| beq 2f /* if exactly 8 args */ |
| subi r9,r5,3 |
| subi r5,r5,8 |
| rlwinm r9,r9,2,0,27 |
| subf r7,r9,r4 |
| mtctr r5 /* copy the 9th and following args */ |
| addi r6,r1,16 |
| addi r8,r7,4 |
| 3: lwzu r10,4(r6) |
| stwu r10,4(r8) |
| bdnz 3b |
| 2: stw r7,_UC_GREGS+(PT_R1*4)(r11) |
| li r6,0 |
| stw r6,0(r7) |
| |
| blr |
| |
| cfi_endproc |
| nop |
| /* |
| * If the function returns, it comes here. We put ucp->uc_link in |
| * r31, which is a callee-saved register. We have to continue with |
| * the context that r31 points to, or exit if it is 0. |
| */ |
| L(novec_exitcode): |
| mr. r3,r31 |
| beq 4f |
| bl __novec_setcontext@local |
| 4: bl HIDDEN_JUMPTARGET(exit) |
| b 4b |
| |
| cfi_startproc |
| END(__novec_makecontext) |
| .previous |
| |
| compat_symbol (libc, __novec_makecontext, makecontext, GLIBC_2_3_3) |
| #endif |
| |
| #if SHLIB_COMPAT (libc, GLIBC_2_1, GLIBC_2_3_3) |
| |
| #define _ERRNO_H 1 |
| #include <bits/errno.h> |
| |
| compat_text_section |
| ENTRY (__makecontext_stub) |
| li r3,ENOSYS |
| b __syscall_error@local |
| END (__makecontext_stub) |
| .previous |
| |
| compat_symbol (libc, __makecontext_stub, makecontext, GLIBC_2_1) |
| |
| #endif |