| /* Set current context. |
| |
| Copyright (C) 2009-2018 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 "ucontext_i.h" |
| #include "ucontext-internal.h" |
| |
| /* int __setcontext (const ucontext_t *ucp) |
| |
| Restores the machine context in UCP and thereby resumes execution |
| in that context. |
| |
| This implementation is intended to be used for *synchronous* context |
| switches only. Therefore, it does not have to restore anything |
| other than the PRESERVED state. */ |
| |
| .text |
| |
| ENTRY (__setcontext) |
| DELOUSE (0) |
| /* Save a copy of UCP. */ |
| mov x9, x0 |
| |
| /* Set the signal mask with |
| rt_sigprocmask (SIG_SETMASK, mask, NULL, _NSIG/8). */ |
| mov x0, #SIG_SETMASK |
| add x1, x9, #UCONTEXT_SIGMASK |
| mov x2, #0 |
| mov x3, #_NSIG8 |
| mov x8, SYS_ify (rt_sigprocmask) |
| svc 0 |
| cbz x0, 1f |
| b C_SYMBOL_NAME (__syscall_error) |
| 1: |
| /* Restore the general purpose registers. */ |
| mov x0, x9 |
| cfi_def_cfa (x0, 0) |
| cfi_offset (x18, oX0 + 18 * SZREG) |
| cfi_offset (x19, oX0 + 19 * SZREG) |
| cfi_offset (x20, oX0 + 20 * SZREG) |
| cfi_offset (x21, oX0 + 21 * SZREG) |
| cfi_offset (x22, oX0 + 22 * SZREG) |
| cfi_offset (x23, oX0 + 23 * SZREG) |
| cfi_offset (x24, oX0 + 24 * SZREG) |
| cfi_offset (x25, oX0 + 25 * SZREG) |
| cfi_offset (x26, oX0 + 26 * SZREG) |
| cfi_offset (x27, oX0 + 27 * SZREG) |
| cfi_offset (x28, oX0 + 28 * SZREG) |
| cfi_offset (x29, oX0 + 29 * SZREG) |
| cfi_offset (x30, oX0 + 30 * SZREG) |
| |
| cfi_offset ( d8, oV0 + 8 * SZVREG) |
| cfi_offset ( d9, oV0 + 9 * SZVREG) |
| cfi_offset (d10, oV0 + 10 * SZVREG) |
| cfi_offset (d11, oV0 + 11 * SZVREG) |
| cfi_offset (d12, oV0 + 12 * SZVREG) |
| cfi_offset (d13, oV0 + 13 * SZVREG) |
| cfi_offset (d14, oV0 + 14 * SZVREG) |
| cfi_offset (d15, oV0 + 15 * SZVREG) |
| ldp x18, x19, [x0, oX0 + 18 * SZREG] |
| ldp x20, x21, [x0, oX0 + 20 * SZREG] |
| ldp x22, x23, [x0, oX0 + 22 * SZREG] |
| ldp x24, x25, [x0, oX0 + 24 * SZREG] |
| ldp x26, x27, [x0, oX0 + 26 * SZREG] |
| ldp x28, x29, [x0, oX0 + 28 * SZREG] |
| ldr x30, [x0, oX0 + 30 * SZREG] |
| ldr x2, [x0, oSP] |
| mov sp, x2 |
| |
| /* Check for FP SIMD context. We don't support restoring |
| contexts created by the kernel, so this context must have |
| been created by getcontext. Hence we can rely on the |
| first extension block being the FP SIMD context. */ |
| add x2, x0, #oEXTENSION |
| |
| mov w3, #(FPSIMD_MAGIC & 0xffff) |
| movk w3, #(FPSIMD_MAGIC >> 16), lsl #16 |
| ldr w1, [x2, #oHEAD + oMAGIC] |
| cmp w1, w3 |
| b.ne 2f |
| |
| /* Restore the FP SIMD context. */ |
| add x3, x2, #oV0 + 8 * SZVREG |
| ldp q8, q9, [x3], #2 * SZVREG |
| ldp q10, q11, [x3], #2 * SZVREG |
| ldp q12, q13, [x3], #2 * SZVREG |
| ldp q14, q15, [x3], #2 * SZVREG |
| |
| add x3, x2, oFPSR |
| |
| ldr w4, [x3] |
| msr fpsr, x4 |
| |
| ldr w4, [x3, oFPCR - oFPSR] |
| msr fpcr, x4 |
| |
| 2: |
| ldr x16, [x0, oPC] |
| /* Restore arg registers. */ |
| ldp x2, x3, [x0, oX0 + 2 * SZREG] |
| ldp x4, x5, [x0, oX0 + 4 * SZREG] |
| ldp x6, x7, [x0, oX0 + 6 * SZREG] |
| ldp x0, x1, [x0, oX0 + 0 * SZREG] |
| /* Jump to the new pc value. */ |
| br x16 |
| PSEUDO_END (__setcontext) |
| weak_alias (__setcontext, setcontext) |
| |
| ENTRY (__startcontext) |
| mov x0, x19 |
| cbnz x0, __setcontext |
| 1: b HIDDEN_JUMPTARGET (exit) |
| END (__startcontext) |
