The previous version used memory operands that gcc (probably dependent
on optimization flags and/or version) could address relative to the
stack pointer, but pushing %ebx onto the stack changed it. Here, the
address of the regs array is put into %esi and the individual members
are written into directly.
static void
__cpuid(int regs[4], int cpuid_leaf)
{
static void
__cpuid(int regs[4], int cpuid_leaf)
{
- int eax, ebx, ecx, edx;
asm volatile (
#if defined(__i386__)
"pushl %%ebx;\n\t"
#endif
asm volatile (
#if defined(__i386__)
"pushl %%ebx;\n\t"
#endif
- "movl %%eax, %0;\n\t"
- "movl %%ebx, %1;\n\t"
- "movl %%ecx, %2;\n\t"
- "movl %%edx, %3;\n\t"
+ "movl %%eax, (%1);\n\t"
+ "movl %%ebx, 4(%1);\n\t"
+ "movl %%ecx, 8(%1);\n\t"
+ "movl %%edx, 12(%1);\n\t"
#if defined(__i386__)
"popl %%ebx;\n\t"
#endif
#if defined(__i386__)
"popl %%ebx;\n\t"
#endif
- :"=m" (eax), "=m" (ebx), "=m" (ecx), "=m" (edx)
- :"r" (cpuid_leaf)
- :"%eax",
+ :"=a" (cpuid_leaf) /* %eax clobbered by CPUID */
+ :"S" (regs), "a" (cpuid_leaf)
+ :
#if !defined(__i386__)
"%ebx",
#endif
#if !defined(__i386__)
"%ebx",
#endif
- "%ecx", "%edx");
-
- regs[0] = eax;
- regs[1] = ebx;
- regs[2] = ecx;
- regs[3] = edx;
+ "%ecx", "%edx", "memory");
}
#endif /* !PLATFORM_WINDOWS */
}
#endif /* !PLATFORM_WINDOWS */