| /* libunwind - a platform-independent unwind library |
| Copyright (C) 2010 Konstantin Belousov <kib@freebsd.org> |
| |
| This file is part of libunwind. |
| |
| Permission is hereby granted, free of charge, to any person obtaining |
| a copy of this software and associated documentation files (the |
| "Software"), to deal in the Software without restriction, including |
| without limitation the rights to use, copy, modify, merge, publish, |
| distribute, sublicense, and/or sell copies of the Software, and to |
| permit persons to whom the Software is furnished to do so, subject to |
| the following conditions: |
| |
| The above copyright notice and this permission notice shall be |
| included in all copies or substantial portions of the Software. |
| |
| THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, |
| EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF |
| MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND |
| NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE |
| LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION |
| OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION |
| WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ |
| |
| #include "offsets.h" |
| |
| .global _Ux86_getcontext |
| .type _Ux86_getcontext, @function |
| _Ux86_getcontext: |
| .cfi_startproc |
| pushl %eax |
| .cfi_adjust_cfa_offset 4 |
| mov 8(%esp),%eax /* ucontext_t* */ |
| popl FREEBSD_UC_MCONTEXT_EAX_OFF(%eax) |
| .cfi_adjust_cfa_offset 4 |
| movl %ebx, FREEBSD_UC_MCONTEXT_EBX_OFF(%eax) |
| movl %ecx, FREEBSD_UC_MCONTEXT_ECX_OFF(%eax) |
| movl %edx, FREEBSD_UC_MCONTEXT_EDX_OFF(%eax) |
| movl %edi, FREEBSD_UC_MCONTEXT_EDI_OFF(%eax) |
| movl %esi, FREEBSD_UC_MCONTEXT_ESI_OFF(%eax) |
| movl %ebp, FREEBSD_UC_MCONTEXT_EBP_OFF(%eax) |
| |
| movl (%esp), %ecx |
| movl %ecx, FREEBSD_UC_MCONTEXT_EIP_OFF(%eax) |
| |
| leal 4(%esp), %ecx /* Exclude the return address. */ |
| movl %ecx, FREEBSD_UC_MCONTEXT_ESP_OFF(%eax) |
| |
| xorl %ecx, %ecx |
| movw %fs, %cx |
| movl %ecx, FREEBSD_UC_MCONTEXT_FS_OFF(%eax) |
| movw %gs, %cx |
| movl %ecx, FREEBSD_UC_MCONTEXT_GS_OFF(%eax) |
| movw %ds, %cx |
| movl %ecx, FREEBSD_UC_MCONTEXT_DS_OFF(%eax) |
| movw %es, %cx |
| movl %ecx, FREEBSD_UC_MCONTEXT_ES_OFF(%eax) |
| movw %ss, %cx |
| movl %ecx, FREEBSD_UC_MCONTEXT_SS_OFF(%eax) |
| movw %cs, %cx |
| movl %ecx, FREEBSD_UC_MCONTEXT_CS_OFF(%eax) |
| |
| pushfl |
| .cfi_adjust_cfa_offset 4 |
| popl FREEBSD_UC_MCONTEXT_EFLAGS_OFF(%eax) |
| .cfi_adjust_cfa_offset -4 |
| |
| movl $0, FREEBSD_UC_MCONTEXT_TRAPNO_OFF(%eax) |
| |
| movl $FREEBSD_UC_MCONTEXT_FPOWNED_FPU,\ |
| FREEBSD_UC_MCONTEXT_OWNEDFP_OFF(%eax) |
| movl $FREEBSD_UC_MCONTEXT_FPFMT_XMM,\ |
| FREEBSD_UC_MCONTEXT_FPFORMAT_OFF(%eax) |
| |
| /* |
| * Require CPU with fxsave implemented, and enabled by OS. |
| * |
| * If passed ucontext is not aligned to 16-byte boundary, |
| * save fpu context into temporary aligned location on stack |
| * and then copy. |
| */ |
| leal FREEBSD_UC_MCONTEXT_FPSTATE_OFF(%eax), %edx |
| testl $0xf, %edx |
| jne 2f |
| fxsave (%edx) /* fast path, passed ucontext save area was aligned */ |
| 1: movl $FREEBSD_UC_MCONTEXT_MC_LEN_VAL,\ |
| FREEBSD_UC_MCONTEXT_MC_LEN_OFF(%eax) |
| |
| xorl %eax, %eax |
| ret |
| |
| 2: movl %edx, %edi /* not aligned, do the dance */ |
| subl $512 + 16, %esp /* save area and 16 bytes for alignment */ |
| .cfi_adjust_cfa_offset 512 + 16 |
| movl %esp, %edx |
| orl $0xf, %edx /* align *%edx to 16-byte up */ |
| incl %edx |
| fxsave (%edx) |
| movl %edx, %esi /* copy to the final destination */ |
| movl $512/4,%ecx |
| rep; movsl |
| addl $512 + 16, %esp /* restore the stack */ |
| .cfi_adjust_cfa_offset -512 - 16 |
| movl FREEBSD_UC_MCONTEXT_ESI_OFF(%eax), %esi |
| movl FREEBSD_UC_MCONTEXT_EDI_OFF(%eax), %edi |
| jmp 1b |
| |
| .cfi_endproc |
| .size _Ux86_getcontext, . - _Ux86_getcontext |
| |
| /* We do not need executable stack. */ |
| .section .note.GNU-stack,"",@progbits |
