[PATCH v4 1/1] Set Prefer_No_AVX512 flag for hygon platform

[Jiamei Xie]

From: Xie jiamei <xiejiamei@hygon.cn>

Benchmarks indicate evex can be more profitable on Hygon hardware
than AVX512. So add Prefer_No_AVX512 to make it run with evex.

Change-Id: Icc59492f71fde7a783a8bd315714ffd6f7ecaf29
Signed-off-by: Li jing <lijing@hygon.cn>
Signed-off-by: Xie jiamei <xiejiamei@hygon.cn>
---
 sysdeps/x86/cpu-features.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/sysdeps/x86/cpu-features.c b/sysdeps/x86/cpu-features.c
index 5d4437ffdf..a404f598ad 100644
--- a/sysdeps/x86/cpu-features.c
+++ b/sysdeps/x86/cpu-features.c
@@ -1129,6 +1129,13 @@ disable_tsx:
 	  cpu_features->preferred[index_arch_AVX_Fast_Unaligned_Load]
 	    &= ~bit_arch_AVX_Fast_Unaligned_Load;
 	}
+      else if (model == 0x7)
+	{
+	  /* Benchmarks indicate evex can be more profitable on Hygon hardware
+	   than AVX512 */
+	  cpu_features->preferred[index_arch_Prefer_No_AVX512]
+	      |= bit_arch_Prefer_No_AVX512;
+	}
     }
   else
     {
-- 
2.42.0