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authorH.J. Lu <hjl.tools@gmail.com>2021-03-07 09:44:18 -0800
committerH.J. Lu <hjl.tools@gmail.com>2021-03-29 07:40:17 -0700
commit4e2d8f352774b56078c34648b14a2412c38384f4 (patch)
treecafad171d93e598b9c6a1a0457853f6cdc98bf1d /sysdeps/x86_64/multiarch/ifunc-memset.h
parent4bd660be40967cd69072f69ebc2ad32bfcc1f206 (diff)
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x86-64: Use ZMM16-ZMM31 in AVX512 memset family functions
Update ifunc-memset.h/ifunc-wmemset.h to select the function optimized
with AVX512 instructions using ZMM16-ZMM31 registers to avoid RTM abort
with usable AVX512VL and AVX512BW since VZEROUPPER isn't needed at
function exit.
Diffstat (limited to 'sysdeps/x86_64/multiarch/ifunc-memset.h')
-rw-r--r--sysdeps/x86_64/multiarch/ifunc-memset.h13
1 files changed, 8 insertions, 5 deletions
diff --git a/sysdeps/x86_64/multiarch/ifunc-memset.h b/sysdeps/x86_64/multiarch/ifunc-memset.h
index 43655fb684..502f946a84 100644
--- a/sysdeps/x86_64/multiarch/ifunc-memset.h
+++ b/sysdeps/x86_64/multiarch/ifunc-memset.h
@@ -53,13 +53,16 @@ IFUNC_SELECTOR (void)
   if (CPU_FEATURE_USABLE_P (cpu_features, AVX512F)
       && !CPU_FEATURES_ARCH_P (cpu_features, Prefer_No_AVX512))
     {
-      if (CPU_FEATURES_ARCH_P (cpu_features, Prefer_No_VZEROUPPER))
-	return OPTIMIZE (avx512_no_vzeroupper);
+      if (CPU_FEATURE_USABLE_P (cpu_features, AVX512VL)
+	  && CPU_FEATURE_USABLE_P (cpu_features, AVX512BW))
+	{
+	  if (CPU_FEATURE_USABLE_P (cpu_features, ERMS))
+	    return OPTIMIZE (avx512_unaligned_erms);
 
-      if (CPU_FEATURE_USABLE_P (cpu_features, ERMS))
-	return OPTIMIZE (avx512_unaligned_erms);
+	  return OPTIMIZE (avx512_unaligned);
+	}
 
-      return OPTIMIZE (avx512_unaligned);
+      return OPTIMIZE (avx512_no_vzeroupper);
     }
 
   if (CPU_FEATURE_USABLE_P (cpu_features, AVX2))