From f7637252da4a202fc8468cb7441e244fee32f1be Mon Sep 17 00:00:00 2001 From: David Carlier Date: Sat, 9 Mar 2024 12:19:36 +0000 Subject: [PATCH] [openmp] __kmp_x86_cpuid fix for i386/PIC builds. --- openmp/runtime/src/kmp.h | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/openmp/runtime/src/kmp.h b/openmp/runtime/src/kmp.h index 1fc31779a217e..7213994f7e75d 100644 --- a/openmp/runtime/src/kmp.h +++ b/openmp/runtime/src/kmp.h @@ -1404,9 +1404,19 @@ extern void __kmp_query_cpuid(kmp_cpuinfo_t *p); // subleaf is only needed for cache and topology discovery and can be set to // zero in most cases static inline void __kmp_x86_cpuid(int leaf, int subleaf, struct kmp_cpuid *p) { +#if KMP_ARCH_X86 && (defined(__pic__) || defined(__PIC__)) + // on i386 arch, the ebx reg. is used by pic, thus we need to preserve from + // being trashed beforehand + __asm__ __volatile__("mov %%ebx, %%edi\n" + "cpuid\n" + "xchg %%edi, %%ebx\n" + : "=a"(p->eax), "=b"(p->ebx), "=c"(p->ecx), "=d"(p->edx) + : "a"(leaf), "c"(subleaf)); +#else __asm__ __volatile__("cpuid" : "=a"(p->eax), "=b"(p->ebx), "=c"(p->ecx), "=d"(p->edx) : "a"(leaf), "c"(subleaf)); +#endif } // Load p into FPU control word static inline void __kmp_load_x87_fpu_control_word(const kmp_int16 *p) {