Add SSSE3-optimized implementation of str{,n}cmp for x86-64.

git-mirror · Aug 8, 2009 · 0fda545 · 0fda545
1 parent 9083bcc
commit 0fda545
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Showing 6 changed files with 194 additions and 47 deletions.
diff --git a/ChangeLog b/ChangeLog
@@ -1,5 +1,14 @@
 2009-08-07  Ulrich Drepper  <drepper@redhat.com>
 
+	* sysdeps/x86_64/strcmp.S: Add support to compile with
+	USE_SSSE3.  In this case palignr is used.
+	* sysdeps/x86_64/multiarch/strcmp.S (strcmp): If SSE4.3 is not
+	available but SSSE3 is, pick __str{,n}cmp_ssse3.
+	* sysdeps/x86_64/multiarch/Makefile [subdir=string] (sysdep_routines):
+	Add strcmp-ssse3 and strncmp-ssse3.
+	* sysdeps/x86_64/multiarch/strcmp-ssse3.S: New file.
+	* sysdeps/x86_64/multiarch/strncmp-ssse3.S: New file.
+
 	* sysdeps/x86_64/multiarch/strcspn-c.c (STRCSPN_SSE42): Avoid
 	warning through fake initialization.
 

diff --git a/sysdeps/x86_64/multiarch/Makefile b/sysdeps/x86_64/multiarch/Makefile
@@ -4,7 +4,7 @@ gen-as-const-headers += ifunc-defines.sym
 endif
 
 ifeq ($(subdir),string)
-sysdep_routines += stpncpy-c strncpy-c
+sysdep_routines += stpncpy-c strncpy-c strcmp-ssse3 strncmp-ssse3
 ifeq (yes,$(config-cflags-sse4))
 sysdep_routines += strcspn-c strpbrk-c strspn-c strstr-c strcasestr-c
 CFLAGS-strcspn-c.c += -msse4

diff --git a/sysdeps/x86_64/multiarch/strcmp-ssse3.S b/sysdeps/x86_64/multiarch/strcmp-ssse3.S
@@ -0,0 +1,3 @@
+#define USE_SSSE3 1
+#define STRCMP __strcmp_ssse3
+#include "../strcmp.S"
diff --git a/sysdeps/x86_64/multiarch/strcmp.S b/sysdeps/x86_64/multiarch/strcmp.S
@@ -34,13 +34,15 @@
 	mov	%r9, %r11
 
 #define STRCMP_SSE42	__strncmp_sse42
+#define STRCMP_SSSE3	__strncmp_ssse3
 #define STRCMP_SSE2	__strncmp_sse2
 #define __GI_STRCMP	__GI_strncmp
 #else
 #define UPDATE_STRNCMP_COUNTER
 #ifndef STRCMP
 #define STRCMP		strcmp
 #define STRCMP_SSE42	__strcmp_sse42
+#define STRCMP_SSSE3	__strcmp_ssse3
 #define STRCMP_SSE2	__strcmp_sse2
 #define __GI_STRCMP	__GI_strcmp
 #endif
@@ -60,10 +62,14 @@ ENTRY(STRCMP)
 	cmpl	$0, __cpu_features+KIND_OFFSET(%rip)
 	jne	1f
 	call	__init_cpu_features
-1:	leaq	STRCMP_SSE2(%rip), %rax
-	testl	$(1<<20), __cpu_features+CPUID_OFFSET+COMMON_CPUID_INDEX_1*CPUID_SIZE+CPUID_ECX_OFFSET(%rip)
-	jz	2f
+1:
 	leaq	STRCMP_SSE42(%rip), %rax
+	testl	$(1<<20), __cpu_features+CPUID_OFFSET+COMMON_CPUID_INDEX_1*CPUID_SIZE+CPUID_ECX_OFFSET(%rip)
+	jnz	2f
+	leaq	STRCMP_SSSE3(%rip), %rax
+	testl	$(1<<9), __cpu_features+CPUID_OFFSET+COMMON_CPUID_INDEX_1*CPUID_SIZE+CPUID_ECX_OFFSET(%rip)
+	jnz	2f
+	leaq	STRCMP_SSE2(%rip), %rax
 2:	ret
 END(STRCMP)
 

diff --git a/sysdeps/x86_64/multiarch/strncmp-ssse3.S b/sysdeps/x86_64/multiarch/strncmp-ssse3.S
@@ -0,0 +1,4 @@
+#define USE_SSSE3 1
+#define STRCMP __strncmp_ssse3
+#define USE_AS_STRNCMP
+#include "../strcmp.S"