1 /* libunwind - a platform-independent unwind library 2 Copyright (C) 2007 Google, Inc 3 Contributed by Arun Sharma <arun.sharma (at) google.com> 4 Copyright (C) 2010 Konstantin Belousov <kib (at) freebsd.org> 5 6 This file is part of libunwind. 7 8 Permission is hereby granted, free of charge, to any person obtaining 9 a copy of this software and associated documentation files (the 10 "Software"), to deal in the Software without restriction, including 11 without limitation the rights to use, copy, modify, merge, publish, 12 distribute, sublicense, and/or sell copies of the Software, and to 13 permit persons to whom the Software is furnished to do so, subject to 14 the following conditions: 15 16 The above copyright notice and this permission notice shall be 17 included in all copies or substantial portions of the Software. 18 19 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 20 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 21 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 22 NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE 23 LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION 24 OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION 25 WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ 26 27 #include "ucontext_i.h" 28 #if defined __linux__ 29 #include <asm/unistd.h> 30 #define SIG_SETMASK 2 31 #define SIGSET_BYTE_SIZE (64/8) 32 #elif defined __FreeBSD__ 33 #include <sys/syscall.h> 34 #endif 35 36 /* int _Ux86_64_setcontext (const ucontext_t *ucp) 37 38 Restores the machine context provided. 39 Unlike the libc implementation, doesn't clobber %rax 40 41 */ 42 .global _Ux86_64_setcontext 43 .type _Ux86_64_setcontext, @function 44 45 _Ux86_64_setcontext: 46 47 #if defined __linux__ 48 /* restore signal mask 49 sigprocmask(SIG_SETMASK, ucp->uc_sigmask, NULL, sizeof(sigset_t)) */ 50 push %rdi 51 mov $__NR_rt_sigprocmask, %rax 52 lea UC_SIGMASK(%rdi), %rsi 53 mov $SIG_SETMASK, %rdi 54 xor %rdx, %rdx 55 mov $SIGSET_BYTE_SIZE, %r10 56 syscall 57 pop %rdi 58 59 /* restore fp state */ 60 mov UC_MCONTEXT_FPREGS_PTR(%rdi),%r8 61 fldenv (%r8) 62 ldmxcsr FPREGS_OFFSET_MXCSR(%r8) 63 #elif defined __FreeBSD__ 64 /* restore signal mask */ 65 pushq %rdi 66 xorl %edx,%edx 67 leaq UC_SIGMASK(%rdi),%rsi 68 movl $3,%edi/* SIG_SETMASK */ 69 movl $SYS_sigprocmask,%eax 70 movq %rcx,%r10 71 syscall 72 popq %rdi 73 74 /* restore fp state */ 75 cmpq $UC_MCONTEXT_FPOWNED_FPU,UC_MCONTEXT_OWNEDFP(%rdi) 76 jne 1f 77 cmpq $UC_MCONTEXT_FPFMT_XMM,UC_MCONTEXT_FPFORMAT(%rdi) 78 jne 1f 79 fxrstor UC_MCONTEXT_FPSTATE(%rdi) 80 1: 81 #else 82 #error Port me 83 #endif 84 85 /* restore the rest of the state */ 86 mov UC_MCONTEXT_GREGS_R8(%rdi),%r8 87 mov UC_MCONTEXT_GREGS_R9(%rdi),%r9 88 mov UC_MCONTEXT_GREGS_RBX(%rdi),%rbx 89 mov UC_MCONTEXT_GREGS_RBP(%rdi),%rbp 90 mov UC_MCONTEXT_GREGS_R12(%rdi),%r12 91 mov UC_MCONTEXT_GREGS_R13(%rdi),%r13 92 mov UC_MCONTEXT_GREGS_R14(%rdi),%r14 93 mov UC_MCONTEXT_GREGS_R15(%rdi),%r15 94 mov UC_MCONTEXT_GREGS_RSI(%rdi),%rsi 95 mov UC_MCONTEXT_GREGS_RDX(%rdi),%rdx 96 mov UC_MCONTEXT_GREGS_RAX(%rdi),%rax 97 mov UC_MCONTEXT_GREGS_RCX(%rdi),%rcx 98 mov UC_MCONTEXT_GREGS_RSP(%rdi),%rsp 99 100 /* push the return address on the stack */ 101 mov UC_MCONTEXT_GREGS_RIP(%rdi),%rcx 102 push %rcx 103 104 mov UC_MCONTEXT_GREGS_RCX(%rdi),%rcx 105 mov UC_MCONTEXT_GREGS_RDI(%rdi),%rdi 106 retq 107 108 .size _Ux86_64_setcontext, . - _Ux86_64_setcontext 109 110 /* We do not need executable stack. */ 111 .section .note.GNU-stack,"",@progbits 112
