ref: 33cf9e2f47067c6545c12a0876af5eb9ce116455
parent: ee6ec6349e7b1d888baa49c064076cef0559b6e4
author: Jonathan Lennox <[email protected]>
date: Mon Aug 3 13:04:23 EDT 2015
Fix cpuid asm on 32-bit PIC.
--- a/celt/x86/x86cpu.c
+++ b/celt/x86/x86cpu.c
@@ -48,14 +48,28 @@
static void cpuid(unsigned int CPUInfo[4], unsigned int InfoType)
{
#if defined(CPU_INFO_BY_ASM)
+#if defined(__i386__) && defined(__PIC__)
+/* %ebx is PIC register in 32-bit, so mustn't clobber it. */
__asm__ __volatile__ (
+ "xchg %%ebx, %1\n"
+ "cpuid\n"
+ "xchg %%ebx, %1\n":
+ "=a" (CPUInfo[0]),
+ "=r" (CPUInfo[1]),
+ "=c" (CPUInfo[2]),
+ "=d" (CPUInfo[3]) :
+ "0" (InfoType)
+ );
+#else
+ __asm__ __volatile__ (
"cpuid":
"=a" (CPUInfo[0]),
"=b" (CPUInfo[1]),
"=c" (CPUInfo[2]),
"=d" (CPUInfo[3]) :
- "a" (InfoType), "c" (0)
+ "0" (InfoType)
);
+#endif
#elif defined(CPU_INFO_BY_C)
__get_cpuid(InfoType, &(CPUInfo[0]), &(CPUInfo[1]), &(CPUInfo[2]), &(CPUInfo[3]));
#endif