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[committed, PATCH] Correct comments in x86_64/multiarch/memcmp.S
- From: "H.J. Lu" <hongjiu dot lu at intel dot com>
- To: GNU C Library <libc-alpha at sourceware dot org>
- Date: Thu, 18 May 2017 14:03:13 -0700
- Subject: [committed, PATCH] Correct comments in x86_64/multiarch/memcmp.S
- Authentication-results: sourceware.org; auth=none
- Reply-to: "H.J. Lu" <hjl dot tools at gmail dot com>
* sysdeps/x86_64/multiarch/memcmp.S (__GI_memcmp): Correct
comments.
---
ChangeLog | 5 +++++
sysdeps/x86_64/multiarch/memcmp.S | 6 +++---
2 files changed, 8 insertions(+), 3 deletions(-)
diff --git a/ChangeLog b/ChangeLog
index 06ef578..5ebd3a0 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2017-05-18 H.J. Lu <hongjiu.lu@intel.com>
+
+ * sysdeps/x86_64/multiarch/memcmp.S (__GI_memcmp): Correct
+ comments.
+
2017-05-18 Siddhesh Poyarekar <siddhesh@sourceware.org>
* elf/Makefile (tst-env-setuid-ENV): Reduce value of
diff --git a/sysdeps/x86_64/multiarch/memcmp.S b/sysdeps/x86_64/multiarch/memcmp.S
index 8262317..6129820 100644
--- a/sysdeps/x86_64/multiarch/memcmp.S
+++ b/sysdeps/x86_64/multiarch/memcmp.S
@@ -56,9 +56,9 @@ END(memcmp)
# ifdef SHARED
# undef libc_hidden_builtin_def
-/* IFUNC doesn't work with the hidden functions in shared library since
- they will be called without setting up EBX needed for PLT which is
- used by IFUNC. */
+/* It doesn't make sense to send libc-internal memcmp calls through a PLT.
+ The speedup we get from using SSE4 instructions is likely eaten away
+ by the indirect call in the PLT. */
# define libc_hidden_builtin_def(name) \
.globl __GI_memcmp; __GI_memcmp = __memcmp_sse2
# endif
--
2.9.4