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Issue 923253002:
Use PNaCl's implementation of setjmp/longjmp for x86-64 (Closed)
Base URL: https://chromium.googlesource.com/native_client/nacl-newlib.git@master| OLD | NEW |
|---|---|
| 1 /* | 1 /* |
| 2 * ==================================================== | 2 * Copyright (c) 2011 The Native Client Authors. All rights reserved. |
| 3 * Copyright (C) 2007 by Ellips BV. All rights reserved. | 3 * Use of this source code is governed by a BSD-style license that can be |
| 4 * | 4 * found in the LICENSE file. |
| 5 * Permission to use, copy, modify, and distribute this | |
| 6 * software is freely granted, provided that this notice | |
| 7 * is preserved. | |
| 8 * ==================================================== | |
| 9 */ | 5 */ |
| 10 | 6 |
| 11 /* | 7 /* This file is copied from pnacl/support/setjmp_x86_64.S in the Native Client |
| 12 ** jmp_buf: | 8 * repository. It should be kept in sync. |
|
Mark Seaborn
2015/02/13 23:02:34
add "with minor modifications" (since there are so
Derek Schuff
2015/02/13 23:31:31
Done.
| |
| 13 ** rbx r12 r13 r14 rip ebp esp | |
| 14 ** 0 8 16 24 32 40 44 | |
| 15 */ | 9 */ |
| 16 | 10 |
| 17 #include "x86_64mach.h" | 11 #define NACL_BLOCK_SHIFT 5 |
| 18 | 12 |
| 19 .global SYM (setjmp) | 13 /* |
| 20 .global SYM (longjmp) | 14 * jump_buf is organized as follows |
| 21 SOTYPE_FUNCTION(setjmp) | 15 * rbx, rbp, rsp, r12, r13, r14, pc |
| 22 SOTYPE_FUNCTION(longjmp) | 16 * NOTE: r15 is neither saved nor restored |
| 17 */ | |
| 18 .text | |
| 19 .p2align NACL_BLOCK_SHIFT | |
| 20 .globl setjmp | |
| 21 .type setjmp, @function | |
| 23 | 22 |
| 24 SYM (setjmp): | 23 /* int setjmp(jmp_buf env) */ |
| 25 movq rbx, %nacl: 0 (r15,rdi) | 24 setjmp: |
| 26 movq r12, %nacl: 8 (r15,rdi) | 25 /* edi has env argument*/ |
| 27 movq r13, %nacl: 16 (r15,rdi) | 26 pop %rdx /* return address */ |
| 28 movq r14, %nacl: 24 (r15,rdi) | |
| 29 movq (rsp), rax | |
| 30 movq rax, %nacl: 32 (r15,rdi) | |
| 31 leaq 8 (rsp), rax | |
| 32 movl ebp, %nacl: 40 (r15,rdi) | |
| 33 movl eax, %nacl: 44 (r15,rdi) | |
| 34 movq $0, rax | |
| 35 pop r11 | |
| 36 nacljmp r11d, r15 | |
| 37 | 27 |
| 38 SYM (longjmp): | 28 /* |
| 39 movq rsi, rax /* Return value */ | 29 * We avoid revealing the top 32 bits of rbp and rsp here. |
| 30 * | |
| 31 * Also note that we don't do: | |
| 32 * pop %r11 | |
| 33 * ... | |
| 34 * movq %r11, %nacl:48(%r15,%rdi) / * save pc * / | |
| 35 * because the latter instruction might be reached via a direct or | |
| 36 * indirect jump when r11 contains the sandbox base address in its | |
| 37 * top 32 bits, and this would write the sandbox base address into | |
| 38 * memory. We treat r11 as a write-only register to avoid | |
| 39 * revealing the sandbox base address to user code. | |
| 40 */ | |
| 41 movq %rbx, %nacl:0(%r15,%rdi) /* save rbx */ | |
| 42 movl %ebp, %nacl:8(%r15,%rdi) /* save rbp/ebp */ | |
| 43 movl %esp, %nacl:16(%r15,%rdi) /* save rsp/esp */ | |
| 44 movq %r12, %nacl:24(%r15,%rdi) /* save r12 */ | |
| 45 movq %r13, %nacl:32(%r15,%rdi) /* save r13 */ | |
| 46 movq %r14, %nacl:40(%r15,%rdi) /* save r14 */ | |
| 47 movq %rdx, %nacl:48(%r15,%rdi) /* save pc */ | |
| 40 | 48 |
| 41 naclrestbp %nacl: 40 (r15,rdi), r15 | 49 xorq %rax, %rax |
| 42 | 50 |
| 43 __CLI | 51 movl %edx, %r11d |
| 44 naclrestsp %nacl: 44 (r15,rdi), r15 | 52 nacljmp %r11d, %r15 |
| 45 pushq %nacl: 32 (r15,rdi) | |
| 46 movq %nacl: 0 (r15,rdi), rbx | |
| 47 movq %nacl: 8 (r15,rdi), r12 | |
| 48 movq %nacl: 16 (r15,rdi), r13 | |
| 49 movq %nacl: 24 (r15,rdi), r14 | |
| 50 __STI | |
| 51 | 53 |
| 52 pop r11 | 54 |
| 53 nacljmp r11d, r15 | 55 .text |
| 56 .p2align NACL_BLOCK_SHIFT | |
| 57 .globl longjmp | |
| 58 .type longjmp, @function | |
| 59 | |
| 60 /* void longjmp(jmp_buf env, int val) */ | |
| 61 longjmp: | |
| 62 /* edi has env argument */ | |
| 63 /* esi has val argument */ | |
| 64 movl %esi, %eax | |
| 65 /* if val is zero, we must return 1 -- otherwise return val */ | |
| 66 testl %eax, %eax | |
| 67 jne .Lskip | |
|
Mark Seaborn
2015/02/13 23:02:34
PNaCl's version has ".skip". Can you avoid unnece
Derek Schuff
2015/02/13 23:31:31
I'll change PNaCl's version too. This version uses
| |
| 68 movl $1, %eax | |
| 69 .Lskip: | |
| 70 movq %nacl:0(%r15,%rdi), %rbx /* restore rbx */ | |
| 71 movq %nacl:8(%r15,%rdi), %rdx /* restore rbp */ | |
| 72 naclrestbp %edx, %r15 | |
| 73 movq %nacl:16(%r15,%rdi), %rdx /* restore rsp */ | |
| 74 naclrestsp %edx, %r15 | |
| 75 movq %nacl:24(%r15,%rdi), %r12 /* restore r12 */ | |
| 76 movq %nacl:32(%r15,%rdi), %r13 /* restore r13 */ | |
| 77 movq %nacl:40(%r15,%rdi), %r14 /* restore r14 */ | |
| 78 movq %nacl:48(%r15,%rdi), %r11 | |
| 79 nacljmp %r11d, %r15 | |
| 80 .p2align NACL_BLOCK_SHIFT | |
| OLD | NEW |
