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-rw-r--r--sysdeps/x86_64/strchr.S191
1 files changed, 157 insertions, 34 deletions
diff --git a/sysdeps/x86_64/strchr.S b/sysdeps/x86_64/strchr.S
index d89f1eba8f..1900b37e63 100644
--- a/sysdeps/x86_64/strchr.S
+++ b/sysdeps/x86_64/strchr.S
@@ -19,51 +19,174 @@
 
 #include <sysdep.h>
 
+# ifndef ALIGN
+#  define ALIGN(n)	.p2align n
+# endif
+
 
 	.text
 ENTRY (strchr)
 	movd	%esi, %xmm1
-	movq	%rdi, %rcx
-	punpcklbw %xmm1, %xmm1
-	andq	$~15, %rdi
-	pxor	%xmm2, %xmm2
+	movl	%edi, %eax
+	andl	$4095, %eax
 	punpcklbw %xmm1, %xmm1
-	orl	$0xffffffff, %esi
-	movdqa	(%rdi), %xmm0
+	cmpl	$4032, %eax
+	punpcklwd %xmm1, %xmm1
 	pshufd	$0, %xmm1, %xmm1
-	subq	%rdi, %rcx
-	movdqa	%xmm0, %xmm3
-	leaq	16(%rdi), %rdi
+	jg	L(cross_page)
+	movdqu	(%rdi), %xmm0
+	pxor	%xmm3, %xmm3
+	movdqa	%xmm0, %xmm4
 	pcmpeqb	%xmm1, %xmm0
-	pcmpeqb	%xmm2, %xmm3
-	shl	%cl, %esi
-	pmovmskb %xmm0, %edx
-	pmovmskb %xmm3, %ecx
-	andl	%esi, %edx
-	andl	%esi, %ecx
-	orl	%edx, %ecx
-	jnz	1f
+	pcmpeqb	%xmm3, %xmm4
+	por	%xmm4, %xmm0
+	pmovmskb %xmm0, %eax
+	test	%eax, %eax
+	je	L(next_48_bytes)
+	bsf	%eax, %eax
+#ifdef AS_STRCHRNUL
+	leaq	(%rdi,%rax), %rax
+#else
+	movl	$0, %edx
+	leaq	(%rdi,%rax), %rax
+	cmpb	%sil, (%rax)
+	cmovne	%rdx, %rax
+#endif
+	ret
 
-2:	movdqa	(%rdi), %xmm0
-	leaq	16(%rdi), %rdi
-	movdqa	%xmm0, %xmm3
+	ALIGN(3)
+	L(next_48_bytes):
+	movdqu	16(%rdi), %xmm0
+	movdqa	%xmm0, %xmm4
 	pcmpeqb	%xmm1, %xmm0
-	pcmpeqb	%xmm2, %xmm3
-	pmovmskb %xmm0, %edx
-	pmovmskb %xmm3, %ecx
-	orl	%edx, %ecx
-	jz	2b
+	pcmpeqb	%xmm3, %xmm4
+	por	%xmm4, %xmm0
+	pmovmskb %xmm0, %ecx
+	movdqu	32(%rdi), %xmm0
+	movdqa	%xmm0, %xmm4
+	pcmpeqb	%xmm1, %xmm0
+	salq	$16, %rcx
+	pcmpeqb	%xmm3, %xmm4
+	por	%xmm4, %xmm0
+	pmovmskb %xmm0, %eax
+	movdqu	48(%rdi), %xmm0
+	pcmpeqb	%xmm0, %xmm3
+	salq	$32, %rax
+	pcmpeqb	%xmm1, %xmm0
+	orq	%rcx, %rax
+	por	%xmm3, %xmm0
+	pmovmskb %xmm0, %ecx
+	salq	$48, %rcx
+	orq	%rcx, %rax
+	testq	%rax, %rax
+	jne	L(return)
+L(loop_start):
+	/* We use this alignment to force loop be aligned to 8 but not
+	   16 bytes.  This gives better sheduling on AMD processors.  */
+	ALIGN(4)
+	pxor	%xmm6, %xmm6
+	andq	$-64, %rdi
+	ALIGN(3)
+L(loop64):
+	addq	$64, %rdi
+	movdqa	(%rdi), %xmm5
+	movdqa	16(%rdi), %xmm2
+	movdqa	32(%rdi), %xmm3
+	pxor	%xmm1, %xmm5
+	movdqa	48(%rdi), %xmm4
+	pxor	%xmm1, %xmm2
+	pxor	%xmm1, %xmm3
+	pminub	(%rdi), %xmm5
+	pxor	%xmm1, %xmm4
+	pminub	16(%rdi), %xmm2
+	pminub	32(%rdi), %xmm3
+	pminub	%xmm2, %xmm5
+	pminub	48(%rdi), %xmm4
+	pminub	%xmm3, %xmm5
+	pminub	%xmm4, %xmm5
+	pcmpeqb %xmm6, %xmm5
+	pmovmskb %xmm5, %eax
+
+	testl	%eax, %eax
+	je	L(loop64)
+
+	movdqa	(%rdi), %xmm5
+	movdqa	%xmm5, %xmm0
+	pcmpeqb	%xmm1, %xmm5
+	pcmpeqb	%xmm6, %xmm0
+	por	%xmm0, %xmm5
+	pcmpeqb %xmm6, %xmm2
+	pcmpeqb %xmm6, %xmm3
+	pcmpeqb %xmm6, %xmm4
+
+	pmovmskb %xmm5, %ecx
+	pmovmskb %xmm2, %eax
+	salq	$16, %rax
+	pmovmskb %xmm3, %r8d
+	pmovmskb %xmm4, %edx
+	salq	$32, %r8
+	orq	%r8, %rax
+	orq	%rcx, %rax
+	salq	$48, %rdx
+	orq	%rdx, %rax
+	ALIGN(3)
+L(return):
+	bsfq	%rax, %rax
+#ifdef AS_STRCHRNUL
+	leaq	(%rdi,%rax), %rax
+#else
+	movl	$0, %edx
+	leaq	(%rdi,%rax), %rax
+	cmpb	%sil, (%rax)
+	cmovne	%rdx, %rax
+#endif
+	ret
+	ALIGN(4)
+
+L(cross_page):
+	movq	%rdi, %rdx
+	pxor	%xmm2, %xmm2
+	andq	$-64, %rdx
+	movdqa	%xmm1, %xmm0
+	movdqa	(%rdx), %xmm3
+	movdqa	%xmm3, %xmm4
+	pcmpeqb	%xmm1, %xmm3
+	pcmpeqb	%xmm2, %xmm4
+	por	%xmm4, %xmm3
+	pmovmskb %xmm3, %r8d
+	movdqa	16(%rdx), %xmm3
+	movdqa	%xmm3, %xmm4
+	pcmpeqb	%xmm1, %xmm3
+	pcmpeqb	%xmm2, %xmm4
+	por	%xmm4, %xmm3
+	pmovmskb %xmm3, %eax
+	movdqa	32(%rdx), %xmm3
+	movdqa	%xmm3, %xmm4
+	pcmpeqb	%xmm1, %xmm3
+	salq	$16, %rax
+	pcmpeqb	%xmm2, %xmm4
+	por	%xmm4, %xmm3
+	pmovmskb %xmm3, %r9d
+	movdqa	48(%rdx), %xmm3
+	pcmpeqb	%xmm3, %xmm2
+	salq	$32, %r9
+	pcmpeqb	%xmm3, %xmm0
+	orq	%r9, %rax
+	orq	%r8, %rax
+	por	%xmm2, %xmm0
+	pmovmskb %xmm0, %ecx
+	salq	$48, %rcx
+	orq	%rcx, %rax
+	movl	%edi, %ecx
+	subb	%dl, %cl
+	shrq	%cl, %rax
+	testq	%rax, %rax
+	jne	L(return)
+	jmp	L(loop_start)
 
-1:	bsfl	%edx, %edx
-	jz	4f
-	bsfl	%ecx, %ecx
-	leaq	-16(%rdi,%rdx), %rax
-	cmpl	%edx, %ecx
-	je	5f
-4:	xorl	%eax, %eax
-5:	ret
 END (strchr)
 
+#ifndef AS_STRCHRNUL
 weak_alias (strchr, index)
 libc_hidden_builtin_def (strchr)
-
+#endif