From: mayshao <mayshao...@zhaoxin.com>

Hi all:
    We reply in PR104688 that ZHAOXIN guarantees that 16-byte VMOVDQA on 
16-byte aligned address is atomic, if memory type of the address is WB. So 
there is no need to clear bit_AVX on ZHAOXIN CPUs.

    Bootstrapped /regtested X86_64.

    Ok for trunk?
BR
Mayshao

libatomic/ChangeLog:

        PR target/104688
        * config/x86/init.c (__libat_feat1_init): Don't clear
        bit_AVX on ZHAOXIN CPUs.
---
 libatomic/config/x86/init.c | 14 --------------
 1 file changed, 14 deletions(-)

diff --git a/libatomic/config/x86/init.c b/libatomic/config/x86/init.c
index a75be3f175c..3740c88a936 100644
--- a/libatomic/config/x86/init.c
+++ b/libatomic/config/x86/init.c
@@ -34,20 +34,6 @@ __libat_feat1_init (void)
   unsigned int eax, ebx, ecx, edx;
   FEAT1_REGISTER = 0;
   __get_cpuid (1, &eax, &ebx, &ecx, &edx);
-#ifdef __x86_64__
-  if ((FEAT1_REGISTER & (bit_AVX | bit_CMPXCHG16B))
-      == (bit_AVX | bit_CMPXCHG16B))
-    {
-      /* Intel SDM guarantees that 16-byte VMOVDQA on 16-byte aligned address
-        is atomic, and AMD is going to do something similar soon.
-        We don't have a guarantee from vendors of other CPUs with AVX,
-        like Zhaoxin and VIA.  */
-      unsigned int ecx2 = 0;
-      __get_cpuid (0, &eax, &ebx, &ecx2, &edx);
-      if (ecx2 != signature_INTEL_ecx && ecx2 != signature_AMD_ecx)
-       FEAT1_REGISTER &= ~bit_AVX;
-    }
-#endif
   /* See the load in load_feat1.  */
   __atomic_store_n (&__libat_feat1, FEAT1_REGISTER, __ATOMIC_RELAXED);
   return FEAT1_REGISTER;
-- 
2.27.0

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