xref: /aosp_15_r20/external/llvm-libc/src/setjmp/x86_64/longjmp.cpp (revision 71db0c75aadcf003ffe3238005f61d7618a3fead)
1 //===-- Implementation of longjmp -----------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "src/setjmp/longjmp.h"
10 #include "include/llvm-libc-macros/offsetof-macro.h"
11 #include "src/__support/common.h"
12 #include "src/__support/macros/config.h"
13 
14 #if !defined(LIBC_TARGET_ARCH_IS_X86)
15 #error "Invalid file include"
16 #endif
17 
18 namespace LIBC_NAMESPACE_DECL {
19 
20 #ifdef __i386__
21 [[gnu::naked]]
22 LLVM_LIBC_FUNCTION(void, longjmp, (jmp_buf, int)) {
23   asm(R"(
24       mov 0x4(%%esp), %%ecx
25       mov 0x8(%%esp), %%eax
26       cmpl $0x1, %%eax
27       adcl $0x0, %%eax
28 
29       mov %c[ebx](%%ecx), %%ebx
30       mov %c[esi](%%ecx), %%esi
31       mov %c[edi](%%ecx), %%edi
32       mov %c[ebp](%%ecx), %%ebp
33       mov %c[esp](%%ecx), %%esp
34 
35       jmp *%c[eip](%%ecx)
36       )" ::[ebx] "i"(offsetof(__jmp_buf, ebx)),
37       [esi] "i"(offsetof(__jmp_buf, esi)), [edi] "i"(offsetof(__jmp_buf, edi)),
38       [ebp] "i"(offsetof(__jmp_buf, ebp)), [esp] "i"(offsetof(__jmp_buf, esp)),
39       [eip] "i"(offsetof(__jmp_buf, eip)));
40 }
41 #else
42 [[gnu::naked]]
43 LLVM_LIBC_FUNCTION(void, longjmp, (jmp_buf, int)) {
44   asm(R"(
45       cmpl $0x1, %%esi
46       adcl $0x0, %%esi
47       movq %%rsi, %%rax
48 
49       movq %c[rbx](%%rdi), %%rbx
50       movq %c[rbp](%%rdi), %%rbp
51       movq %c[r12](%%rdi), %%r12
52       movq %c[r13](%%rdi), %%r13
53       movq %c[r14](%%rdi), %%r14
54       movq %c[r15](%%rdi), %%r15
55       movq %c[rsp](%%rdi), %%rsp
56       jmpq *%c[rip](%%rdi)
57       )" ::[rbx] "i"(offsetof(__jmp_buf, rbx)),
58       [rbp] "i"(offsetof(__jmp_buf, rbp)), [r12] "i"(offsetof(__jmp_buf, r12)),
59       [r13] "i"(offsetof(__jmp_buf, r13)), [r14] "i"(offsetof(__jmp_buf, r14)),
60       [r15] "i"(offsetof(__jmp_buf, r15)), [rsp] "i"(offsetof(__jmp_buf, rsp)),
61       [rip] "i"(offsetof(__jmp_buf, rip)));
62 }
63 #endif
64 
65 } // namespace LIBC_NAMESPACE_DECL
66