ObjFW  Diff

#if defined(OF_X86_64) || defined(OF_X86)
static OF_INLINE struct x86_regs OF_CONST_FUNC
x86_cpuid(uint32_t eax, uint32_t ecx)
{
	struct x86_regs regs;

# if defined(OF_X86_64_ASM)
	__asm__(
	__asm__ (
	    "cpuid"
	    : "=a"(regs.eax), "=b"(regs.ebx), "=c"(regs.ecx), "=d"(regs.edx)
	    : "a"(eax), "c"(ecx)
	);
# elif defined(OF_X86_ASM)
	/*
	 * This workaround is required by GCC when using -fPIC, as ebx is a
	 * special register in PIC code. Yes, GCC is indeed not able to just
	 * push a register onto the stack before the __asm__ block and to pop
	 * it afterwards.
	 */
	__asm__(
	__asm__ (
	    "pushl	%%ebx\n\t"
	    "cpuid\n\t"
	    "movl	%%ebx, %1\n\t"
	    "popl	%%ebx"
	    : "=a"(regs.eax), "=r"(regs.ebx), "=c"(regs.ecx), "=d"(regs.edx)
	    : "a"(eax), "c"(ecx)
	);