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| author | Konstantin Belousov <kostik@pooma.home> | 2010-05-02 17:06:24 +0300 |
|---|---|---|
| committer | Konstantin Belousov <kostik@pooma.home> | 2010-05-02 17:06:24 +0300 |
| commit | c84005e9c8226917747c1e8ba31a13bff25b0c84 (patch) | |
| tree | 01b9e47703350a6c97d4fdd0fbedd8154addcba0 | |
| parent | b73c618a3135e2e98a279c957240d6d00a192166 (diff) | |
| download | libunwind-c84005e9c8226917747c1e8ba31a13bff25b0c84.tar.gz | |
Add unwind annotations for freebsd/x86 getcontext.S.
Rearrange the code to put the slow branch out of main body,
and pinch the fixed amount of stack space to be able to annotate
the code.
| -rw-r--r-- | src/x86/getcontext-freebsd.S | 37 |
1 files changed, 22 insertions, 15 deletions
diff --git a/src/x86/getcontext-freebsd.S b/src/x86/getcontext-freebsd.S index dfeb4328..670eff1a 100644 --- a/src/x86/getcontext-freebsd.S +++ b/src/x86/getcontext-freebsd.S @@ -29,8 +29,10 @@ WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ _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) @@ -59,7 +61,9 @@ _Ux86_getcontext: 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) @@ -77,27 +81,30 @@ _Ux86_getcontext: */ leal FREEBSD_UC_MCONTEXT_FPSTATE_OFF(%eax), %edx testl $0xf, %edx - je 1f - movl %edx, %edi + 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 - subl $512, %esp - andl $~0xf, %esp - fxsave (%esp) - movl %esp, %esi + 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 - movl %edx, %esp + 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 2f -1: fxsave (%edx) -2: + jmp 1b - movl $FREEBSD_UC_MCONTEXT_MC_LEN_VAL,\ - FREEBSD_UC_MCONTEXT_MC_LEN_OFF(%eax) - - xorl %eax, %eax - ret .cfi_endproc .size _Ux86_getcontext, . - _Ux86_getcontext |