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Re: [PATCH] Set fast unaligned load flag for new Intel microarchitecture.
- From: Andreas Jaeger <aj at suse dot com>
- To: Dmitrieva Liubov <liubov dot dmitrieva at gmail dot com>
- Cc: libc-alpha at sourceware dot org
- Date: Fri, 14 Jun 2013 13:13:27 +0200
- Subject: Re: [PATCH] Set fast unaligned load flag for new Intel microarchitecture.
- References: <CAHjhQ92vybopdpv02o+QtW3Gq++nzbb3VJ=+pCzZG3cDMmLokg at mail dot gmail dot com>
On 06/14/2013 12:35 PM, Dmitrieva Liubov wrote:
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.
This needs proper formatting, please check before committing - and name
the function you change like:
* sysdeps/x86_64/multiarch/init-arch.c (__init_cpu_features):
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. */
Say in the comment that unaligned versions are faster than SSSE3.
Otherwise fine,
Andreas
+ __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
--
Andreas Jaeger aj@{suse.com,opensuse.org} Twitter/Identica: jaegerandi
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