的后续是为一个64位的机测试。如果您有32位机器,请删除64位齿轮,然后更改flag64 - > flag32(并使用pushfd
而不是pushfq
)。实际上,我发现我只需要检查标志寄存器中的CY(进位)和OV(溢出)(我通常使用jc
,jnc
,jo
和jno
进行检测)。
#include <stdio.h>
#include <stdint.h>
#define HIGH32(x) ((uint32_t)(((uint64_t)x)>>32))
#define LOW32(x) ((uint32_t)(((uint64_t)x)& 0xFFFFFFFF))
int main(int argc, char** argv)
{
uint32_t eax32, ebx32, ecx32, edx32;
uint64_t rax64, rbx64, rcx64, rdx64;
asm (
"movl %%eax, %[a1] ;"
"movl %%ebx, %[b1] ;"
"movl %%ecx, %[c1] ;"
"movl %%edx, %[d1] ;"
"movq %%rax, %[a2] ;"
"movq %%rbx, %[b2] ;"
"movq %%rcx, %[c2] ;"
"movq %%rdx, %[d2] ;"
:
[a1] "=m" (eax32), [b1] "=m" (ebx32), [c1] "=m" (ecx32), [d1] "=m" (edx32),
[a2] "=m" (rax64), [b2] "=m" (rbx64), [c2] "=m" (rcx64), [d2] "=m" (rdx64)
);
printf("eax=%08x\n", eax32);
printf("ebx=%08x\n", ebx32);
printf("ecx=%08x\n", ecx32);
printf("edx=%08x\n", edx32);
printf("rax=%08x%08x\n", HIGH32(rax64), LOW32(rax64));
printf("bax=%08x%08x\n", HIGH32(rbx64), LOW32(rbx64));
printf("cax=%08x%08x\n", HIGH32(rcx64), LOW32(rcx64));
printf("dax=%08x%08x\n", HIGH32(rdx64), LOW32(rdx64));
uint64_t flags;
asm (
"pushfq ;"
"pop %[f1] ;"
:
[f1] "=m" (flags)
);
printf("flags=%08x%08x", HIGH32(flags), LOW32(flags));
if(flags & (1 << 0)) // Carry
printf(" (C1");
else
printf(" (C0");
if(flags & (1 << 2)) // Parity
printf(" P1");
else
printf(" P0");
if(flags & (1 << 4)) // Adjust
printf(" A1");
else
printf(" A0");
if(flags & (1 << 6)) // Zero
printf(" Z1");
else
printf(" Z0");
if(flags & (1 << 7)) // Sign
printf(" S1");
else
printf(" S0");
if(flags & (1 << 11)) // Overflow
printf(" O1)\n");
else
printf(" O0)\n");
return 0;
}
来源
2011-06-19 20:59:05
jww
如何从jmp_buf结构中重建寄存器并不是很清楚。我在这里找到它的源代码: http://ccrma.stanford.edu/courses/250a/docs/avrgcc/setjmp_8h-source.html 生产不改变寄存器的代码的任何想法?有些PUSH可以帮助... – 2008-11-09 17:55:17
我认为得到整个EFLAGS寄存器,但所有SH *得到正确的位会使它不清楚发生了什么。类似于我想要用Jcc做的事情。 – 2008-11-09 17:57:13