static void __inline__ v3_cpuid(uint32_t target,
uint32_t * eax, uint32_t * ebx,
uint32_t * ecx, uint32_t * edx) {
+#ifdef __V3_64BIT__
+ // avoid rbx on -FPIC - gcc likes to own rbx even on 64 bit PIC code
__asm__ __volatile__ (
+ "pushq %%rbx\n\t"
+ "movq %%rdi, %%rbx\n\t"
"cpuid\n\t"
- : "=a" (*eax), "=b" (*ebx), "=c" (*ecx), "=d" (*edx)
+ "movq %%rbx, %%rdi\n\t"
+ "popq %%rbx\n\t"
+ : "=a" (*eax), "=D" (*ebx), "=c" (*ecx), "=d" (*edx)
: "0" (target), "2" (*ecx)
);
+#elif __V3_32BIT__
+ // 32 bit code compiled with -fPIC, cannot use ebx as an ouput reg. Fantastic.
+ __asm__ __volatile__ (
+ "pushl %%ebx\n\t"
+ "movl %%edi, %%ebx\n\t"
+ "cpuid\n\t"
+ "movl %%ebx, %%edi\n\t"
+ "popl %%ebx\n\t"
+ : "=a" (*eax), "=D" (*ebx), "=c" (*ecx), "=d" (*edx)
+ : "0" (target), "2" (*ecx)
+ );
+#endif
return;
}