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Diffstat (limited to 'sysdeps/x86/cpu-features.c')
-rw-r--r--sysdeps/x86/cpu-features.c14
1 files changed, 14 insertions, 0 deletions
diff --git a/sysdeps/x86/cpu-features.c b/sysdeps/x86/cpu-features.c
index 9ce4b495a5..11b9af2231 100644
--- a/sysdeps/x86/cpu-features.c
+++ b/sysdeps/x86/cpu-features.c
@@ -205,6 +205,20 @@ init_cpu_features (struct cpu_features *cpu_features)
if (CPU_FEATURES_ARCH_P (cpu_features, AVX2_Usable))
cpu_features->feature[index_arch_AVX_Fast_Unaligned_Load]
|= bit_arch_AVX_Fast_Unaligned_Load;
+
+ /* To avoid SSE transition penalty, use _dl_runtime_resolve_slow.
+ If XGETBV suports ECX == 1, use _dl_runtime_resolve_opt. */
+ cpu_features->feature[index_arch_Use_dl_runtime_resolve_slow]
+ |= bit_arch_Use_dl_runtime_resolve_slow;
+ if (cpu_features->max_cpuid >= 0xd)
+ {
+ unsigned int eax;
+
+ __cpuid_count (0xd, 1, eax, ebx, ecx, edx);
+ if ((eax & (1 << 2)) != 0)
+ cpu_features->feature[index_arch_Use_dl_runtime_resolve_opt]
+ |= bit_arch_Use_dl_runtime_resolve_opt;
+ }
}
/* This spells out "AuthenticAMD". */
else if (ebx == 0x68747541 && ecx == 0x444d4163 && edx == 0x69746e65)