commit c9afcaaafaf9126a973883528eed8d0058a264c0
Author: H.J. Lu <hjl.tools@gmail.com>
Date:   Tue Dec 15 11:46:54 2015 -0800
 
    Enable Silvermont optimizations for Knights Landing
 
    Knights Landing processor is based on Silvermont.  This patch enables
    Silvermont optimizations for Knights Landing.
 
        * sysdeps/x86/cpu-features.c (init_cpu_features): Enable
        Silvermont optimizations for Knights Landing.
 
diff --git a/sysdeps/x86/cpu-features.c b/sysdeps/x86/cpu-features.c
index fba3ef0..aff894c 100644
--- a/sysdeps/x86/cpu-features.c
+++ b/sysdeps/x86/cpu-features.c
@@ -78,6 +78,9 @@ init_cpu_features (struct cpu_features *cpu_features)
 	      cpu_features->feature[index_Slow_BSF] |= bit_Slow_BSF;
 	      break;
 
+	    case 0x57:
+	      /* Knights Landing.  Enable Silvermont optimizations.  */
+
 	    case 0x37:
 	    case 0x4a:
 	    case 0x4d: