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[PATCH] Set fast unaligned load flag for new Intel microarchitecture.


I have small patch for new Intel Silvermont machines.

http://newsroom.intel.com/community/intel_newsroom/blog/2013/05/06/intel-launches-low-power-high-performance-silvermont-microarchitecture

Ok for 2.18?

I checked this on my machine and see that strcpy, ... unaligned
versions are faster than ssse3 versions.

ChangeLog:

 2013-06-14  Liubov Dmitrieva  <liubov.dmitrieva@intel.com>

        * .sysdeps/x86_64/multiarch/init-arch.c: Set
bit_Fast_Unaligned_Load for new
       Intel Silvermont architecture.


diff --git a/sysdeps/x86_64/multiarch/init-arch.c b/sysdeps/x86_64/multiarch/ini
index 7daaf46..23b1b98 100644
--- a/sysdeps/x86_64/multiarch/init-arch.c
+++ b/sysdeps/x86_64/multiarch/init-arch.c
@@ -77,7 +77,11 @@ __init_cpu_features (void)
              /* BSF is slow on Atom.  */
              __cpu_features.feature[index_Slow_BSF] |= bit_Slow_BSF;
              break;
-
+           case 0x37:
+             /* Silvermont.  */
+             __cpu_features.feature[index_Fast_Unaligned_Load]
+                               |= bit_Fast_Unaligned_Load;
+             break;
            default:
              /* Unknown family 0x06 processors.  Assuming this is one
                 of Core i3/i5/i7 processors if AVX is available.  */



--
Liubov Dmitrieva
Intel Corporation


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