Add 64-bit Silvermont-optimized string/memory functions.

Add following functions:
bcopy, bzero, memcpy, memmove, memset, stpcpy, stpncpy, strcat, strcpy,
strlen, strncat, strncpy, memcmp, strcmp, strncmp.
Set all these functions as the default ones.

Change-Id: Ic66b250ad8c349a43d25e2d4dea075604f6df6ac
Signed-off-by: Varvara Rainchik <varvara.rainchik@intel.com>
diff --git a/libc/arch-x86_64/string/ssse3-strcmp-slm.S b/libc/arch-x86_64/string/ssse3-strcmp-slm.S
new file mode 100644
index 0000000..0dd8c27
--- /dev/null
+++ b/libc/arch-x86_64/string/ssse3-strcmp-slm.S
@@ -0,0 +1,1925 @@
+/*
+Copyright (c) 2014, Intel Corporation
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+    * Redistributions of source code must retain the above copyright notice,
+    * this list of conditions and the following disclaimer.
+
+    * Redistributions in binary form must reproduce the above copyright notice,
+    * this list of conditions and the following disclaimer in the documentation
+    * and/or other materials provided with the distribution.
+
+    * Neither the name of Intel Corporation nor the names of its contributors
+    * may be used to endorse or promote products derived from this software
+    * without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+#ifdef USE_AS_STRNCMP
+/* Since the counter, %r11, is unsigned, we branch to strcmp_exitz
+   if the new counter > the old one or is 0.  */
+#define UPDATE_STRNCMP_COUNTER				\
+	/* calculate left number to compare */		\
+	lea	-16(%rcx, %r11), %r9;			\
+	cmp	%r9, %r11;				\
+	jb	L(strcmp_exitz);			\
+	test	%r9, %r9;				\
+	je	L(strcmp_exitz);			\
+	mov	%r9, %r11
+
+#else
+#define UPDATE_STRNCMP_COUNTER
+#ifndef STRCMP
+#define STRCMP		strcmp
+#endif
+#endif
+
+#ifndef L
+# define L(label)	.L##label
+#endif
+
+#ifndef cfi_startproc
+# define cfi_startproc			.cfi_startproc
+#endif
+
+#ifndef cfi_endproc
+# define cfi_endproc			.cfi_endproc
+#endif
+
+#ifndef ENTRY
+# define ENTRY(name)			\
+	.type name,  @function; 	\
+	.globl name;			\
+	.p2align 4;			\
+name:					\
+	cfi_startproc
+#endif
+
+#ifndef END
+# define END(name)			\
+	cfi_endproc;			\
+	.size name, .-name
+#endif
+#define RETURN ret
+	.section .text.ssse3,"ax",@progbits
+ENTRY (STRCMP)
+/*
+ * This implementation uses SSE to compare up to 16 bytes at a time.
+ */
+#ifdef USE_AS_STRNCMP
+	test	%rdx, %rdx
+	je	L(strcmp_exitz)
+	cmp	$1, %rdx
+	je	L(Byte0)
+	mov	%rdx, %r11
+#endif
+	mov	%esi, %ecx
+	mov	%edi, %eax
+/* Use 64bit AND here to avoid long NOP padding.  */
+	and	$0x3f, %rcx		/* rsi alignment in cache line */
+	and	$0x3f, %rax		/* rdi alignment in cache line */
+	cmp	$0x30, %ecx
+	ja	L(crosscache)	/* rsi: 16-byte load will cross cache line */
+	cmp	$0x30, %eax
+	ja	L(crosscache)	/* rdi: 16-byte load will cross cache line */
+	movlpd	(%rdi), %xmm1
+	movlpd	(%rsi), %xmm2
+	movhpd	8(%rdi), %xmm1
+	movhpd	8(%rsi), %xmm2
+	pxor	%xmm0, %xmm0		/* clear %xmm0 for null char checks */
+	pcmpeqb	%xmm1, %xmm0		/* Any null chars? */
+	pcmpeqb	%xmm2, %xmm1		/* compare first 16 bytes for equality */
+	psubb	%xmm0, %xmm1		/* packed sub of comparison results*/
+	pmovmskb %xmm1, %edx
+	sub	$0xffff, %edx		/* if first 16 bytes are same, edx == 0xffff */
+	jnz	L(less16bytes)	/* If not, find different value or null char */
+#ifdef USE_AS_STRNCMP
+	sub	$16, %r11
+	jbe	L(strcmp_exitz)	/* finish comparision */
+#endif
+	add	$16, %rsi		/* prepare to search next 16 bytes */
+	add	$16, %rdi		/* prepare to search next 16 bytes */
+
+	/*
+	 * Determine source and destination string offsets from 16-byte alignment.
+	 * Use relative offset difference between the two to determine which case
+	 * below to use.
+	 */
+	.p2align 4
+L(crosscache):
+	and	$0xfffffffffffffff0, %rsi	/* force %rsi is 16 byte aligned */
+	and	$0xfffffffffffffff0, %rdi	/* force %rdi is 16 byte aligned */
+	mov	$0xffff, %edx			/* for equivalent offset */
+	xor	%r8d, %r8d
+	and	$0xf, %ecx			/* offset of rsi */
+	and	$0xf, %eax			/* offset of rdi */
+	cmp	%eax, %ecx
+	je	L(ashr_0)			/* rsi and rdi relative offset same */
+	ja	L(bigger)
+	mov	%edx, %r8d			/* r8d is offset flag for exit tail */
+	xchg	%ecx, %eax
+	xchg	%rsi, %rdi
+L(bigger):
+	lea	15(%rax), %r9
+	sub	%rcx, %r9
+	lea	L(unaligned_table)(%rip), %r10
+	movslq	(%r10, %r9,4), %r9
+	lea	(%r10, %r9), %r10
+	jmp	*%r10				/* jump to corresponding case */
+
+/*
+ * The following cases will be handled by ashr_0
+ *  rcx(offset of rsi)  rax(offset of rdi)  relative offset  corresponding case
+ *        n(0~15)            n(0~15)           15(15+ n-n)         ashr_0
+ */
+	.p2align 4
+L(ashr_0):
+
+	movdqa	(%rsi), %xmm1
+	pxor	%xmm0, %xmm0			/* clear %xmm0 for null char check */
+	pcmpeqb	%xmm1, %xmm0			/* Any null chars? */
+	pcmpeqb	(%rdi), %xmm1			/* compare 16 bytes for equality */
+	psubb	%xmm0, %xmm1			/* packed sub of comparison results*/
+	pmovmskb %xmm1, %r9d
+	shr	%cl, %edx			/* adjust 0xffff for offset */
+	shr	%cl, %r9d			/* adjust for 16-byte offset */
+	sub	%r9d, %edx
+	/*
+	 * edx must be the same with r9d if in left byte (16-rcx) is equal to
+	 * the start from (16-rax) and no null char was seen.
+	 */
+	jne	L(less32bytes)		/* mismatch or null char */
+	UPDATE_STRNCMP_COUNTER
+	mov	$16, %rcx
+	mov	$16, %r9
+	pxor	%xmm0, %xmm0			/* clear xmm0, may have changed above */
+
+	/*
+	 * Now both strings are aligned at 16-byte boundary. Loop over strings
+	 * checking 32-bytes per iteration.
+	 */
+	.p2align 4
+L(loop_ashr_0):
+	movdqa	(%rsi, %rcx), %xmm1
+	movdqa	(%rdi, %rcx), %xmm2
+
+	pcmpeqb	%xmm1, %xmm0
+	pcmpeqb	%xmm2, %xmm1
+	psubb	%xmm0, %xmm1
+	pmovmskb %xmm1, %edx
+	sub	$0xffff, %edx
+	jnz	L(exit)		/* mismatch or null char seen */
+
+#ifdef USE_AS_STRNCMP
+	sub	$16, %r11
+	jbe	L(strcmp_exitz)
+#endif
+	add	$16, %rcx
+	movdqa	(%rsi, %rcx), %xmm1
+	movdqa	(%rdi, %rcx), %xmm2
+
+	pcmpeqb	%xmm1, %xmm0
+	pcmpeqb	%xmm2, %xmm1
+	psubb	%xmm0, %xmm1
+	pmovmskb %xmm1, %edx
+	sub	$0xffff, %edx
+	jnz	L(exit)
+#ifdef USE_AS_STRNCMP
+	sub	$16, %r11
+	jbe	L(strcmp_exitz)
+#endif
+	add	$16, %rcx
+	jmp	L(loop_ashr_0)
+
+/*
+ * The following cases will be handled by ashr_1
+ * rcx(offset of rsi)  rax(offset of rdi)   relative offset   	corresponding case
+ *        n(15)            n -15            0(15 +(n-15) - n)         ashr_1
+ */
+	.p2align 4
+L(ashr_1):
+	pxor	%xmm0, %xmm0
+	movdqa	(%rdi), %xmm2
+	movdqa	(%rsi), %xmm1
+	pcmpeqb	%xmm1, %xmm0		/* Any null chars? */
+	pslldq	$15, %xmm2		/* shift first string to align with second */
+	pcmpeqb	%xmm1, %xmm2		/* compare 16 bytes for equality */
+	psubb	%xmm0, %xmm2		/* packed sub of comparison results*/
+	pmovmskb %xmm2, %r9d
+	shr	%cl, %edx		/* adjust 0xffff for offset */
+	shr	%cl, %r9d		/* adjust for 16-byte offset */
+	sub	%r9d, %edx
+	jnz	L(less32bytes)	/* mismatch or null char seen */
+	movdqa	(%rdi), %xmm3
+	UPDATE_STRNCMP_COUNTER
+
+	pxor	%xmm0, %xmm0
+	mov	$16, %rcx		/* index for loads*/
+	mov	$1, %r9d		/* byte position left over from less32bytes case */
+	/*
+	 * Setup %r10 value allows us to detect crossing a page boundary.
+	 * When %r10 goes positive we have crossed a page boundary and
+	 * need to do a nibble.
+	 */
+	lea	1(%rdi), %r10
+	and	$0xfff, %r10		/* offset into 4K page */
+	sub	$0x1000, %r10		/* subtract 4K pagesize */
+
+	.p2align 4
+L(loop_ashr_1):
+	add	$16, %r10
+	jg	L(nibble_ashr_1)	/* cross page boundary */
+
+L(gobble_ashr_1):
+	movdqa	(%rsi, %rcx), %xmm1
+	movdqa	(%rdi, %rcx), %xmm2
+	movdqa	%xmm2, %xmm4		 /* store for next cycle */
+
+	palignr $1, %xmm3, %xmm2        /* merge into one 16byte value */
+
+	pcmpeqb	%xmm1, %xmm0
+	pcmpeqb	%xmm2, %xmm1
+	psubb	%xmm0, %xmm1
+	pmovmskb %xmm1, %edx
+	sub	$0xffff, %edx
+	jnz	L(exit)
+
+#ifdef USE_AS_STRNCMP
+	sub	$16, %r11
+	jbe	L(strcmp_exitz)
+#endif
+	add	$16, %rcx
+	movdqa	%xmm4, %xmm3
+
+	add	$16, %r10
+	jg	L(nibble_ashr_1)	/* cross page boundary */
+
+	movdqa	(%rsi, %rcx), %xmm1
+	movdqa	(%rdi, %rcx), %xmm2
+	movdqa	%xmm2, %xmm4		/* store for next cycle */
+
+	palignr $1, %xmm3, %xmm2        /* merge into one 16byte value */
+
+	pcmpeqb	%xmm1, %xmm0
+	pcmpeqb	%xmm2, %xmm1
+	psubb	%xmm0, %xmm1
+	pmovmskb %xmm1, %edx
+	sub	$0xffff, %edx
+	jnz	L(exit)
+
+#ifdef USE_AS_STRNCMP
+	sub	$16, %r11
+	jbe	L(strcmp_exitz)
+#endif
+	add	$16, %rcx
+	movdqa	%xmm4, %xmm3
+	jmp	L(loop_ashr_1)
+
+	/*
+	 * Nibble avoids loads across page boundary. This is to avoid a potential
+	 * access into unmapped memory.
+	 */
+	.p2align 4
+L(nibble_ashr_1):
+	pcmpeqb	%xmm3, %xmm0		 /* check nibble for null char*/
+	pmovmskb %xmm0, %edx
+	test	$0xfffe, %edx
+	jnz	L(ashr_1_exittail)	/* find null char*/
+
+#ifdef USE_AS_STRNCMP
+	cmp	$14, %r11
+	jbe	L(ashr_1_exittail)
+#endif
+
+	pxor	%xmm0, %xmm0
+	sub	$0x1000, %r10		/* substract 4K from %r10 */
+	jmp	L(gobble_ashr_1)
+
+	/*
+	 * Once find null char, determine if there is a string mismatch
+	 * before the null char.
+	 */
+	.p2align 4
+L(ashr_1_exittail):
+	movdqa	(%rsi, %rcx), %xmm1
+	psrldq	$1, %xmm0
+	psrldq	$1, %xmm3
+	jmp	L(aftertail)
+
+/*
+ * The following cases will be handled by ashr_2
+ * rcx(offset of rsi)  rax(offset of rdi)   relative offset   	corresponding case
+ *        n(14~15)            n -14         1(15 +(n-14) - n)         ashr_2
+ */
+	.p2align 4
+L(ashr_2):
+	pxor	%xmm0, %xmm0
+	movdqa	(%rdi), %xmm2
+	movdqa	(%rsi), %xmm1
+	pcmpeqb	%xmm1, %xmm0
+	pslldq	$14, %xmm2
+	pcmpeqb	%xmm1, %xmm2
+	psubb	%xmm0, %xmm2
+	pmovmskb %xmm2, %r9d
+	shr	%cl, %edx
+	shr	%cl, %r9d
+	sub	%r9d, %edx
+	jnz	L(less32bytes)
+	movdqa	(%rdi), %xmm3
+	UPDATE_STRNCMP_COUNTER
+
+	pxor	%xmm0, %xmm0
+	mov	$16, %rcx	/* index for loads */
+	mov	$2, %r9d	/* byte position left over from less32bytes case */
+	/*
+	 * Setup %r10 value allows us to detect crossing a page boundary.
+	 * When %r10 goes positive we have crossed a page boundary and
+	 * need to do a nibble.
+	 */
+	lea	2(%rdi), %r10
+	and	$0xfff, %r10	/* offset into 4K page */
+	sub	$0x1000, %r10	/* subtract 4K pagesize */
+
+	.p2align 4
+L(loop_ashr_2):
+	add	$16, %r10
+	jg	L(nibble_ashr_2)
+
+L(gobble_ashr_2):
+	movdqa	(%rsi, %rcx), %xmm1
+	movdqa	(%rdi, %rcx), %xmm2
+	movdqa	%xmm2, %xmm4
+
+	palignr $2, %xmm3, %xmm2        /* merge into one 16byte value */
+
+	pcmpeqb	%xmm1, %xmm0
+	pcmpeqb	%xmm2, %xmm1
+	psubb	%xmm0, %xmm1
+	pmovmskb %xmm1, %edx
+	sub	$0xffff, %edx
+	jnz	L(exit)
+
+#ifdef USE_AS_STRNCMP
+	sub	$16, %r11
+	jbe	L(strcmp_exitz)
+#endif
+
+	add	$16, %rcx
+	movdqa	%xmm4, %xmm3
+
+	add	$16, %r10
+	jg	L(nibble_ashr_2)	/* cross page boundary */
+
+	movdqa	(%rsi, %rcx), %xmm1
+	movdqa	(%rdi, %rcx), %xmm2
+	movdqa	%xmm2, %xmm4
+
+	palignr $2, %xmm3, %xmm2        /* merge into one 16byte value */
+
+	pcmpeqb	%xmm1, %xmm0
+	pcmpeqb	%xmm2, %xmm1
+	psubb	%xmm0, %xmm1
+	pmovmskb %xmm1, %edx
+	sub	$0xffff, %edx
+	jnz	L(exit)
+
+#ifdef USE_AS_STRNCMP
+	sub	$16, %r11
+	jbe	L(strcmp_exitz)
+#endif
+
+	add	$16, %rcx
+	movdqa	%xmm4, %xmm3
+	jmp	L(loop_ashr_2)
+
+	.p2align 4
+L(nibble_ashr_2):
+	pcmpeqb	%xmm3, %xmm0		/* check nibble for null char */
+	pmovmskb %xmm0, %edx
+	test	$0xfffc, %edx
+	jnz	L(ashr_2_exittail)
+
+#ifdef USE_AS_STRNCMP
+	cmp	$13, %r11
+	jbe	L(ashr_2_exittail)
+#endif
+
+	pxor	%xmm0, %xmm0
+	sub	$0x1000, %r10
+	jmp	L(gobble_ashr_2)
+
+	.p2align 4
+L(ashr_2_exittail):
+	movdqa	(%rsi, %rcx), %xmm1
+	psrldq	$2, %xmm0
+	psrldq	$2, %xmm3
+	jmp	L(aftertail)
+
+/*
+ * The following cases will be handled by ashr_3
+ *  rcx(offset of rsi)  rax(offset of rdi)  relative offset	 corresponding case
+ *        n(13~15)            n -13         2(15 +(n-13) - n)         ashr_3
+ */
+	.p2align 4
+L(ashr_3):
+	pxor	%xmm0, %xmm0
+	movdqa	(%rdi), %xmm2
+	movdqa	(%rsi), %xmm1
+	pcmpeqb	%xmm1, %xmm0
+	pslldq	$13, %xmm2
+	pcmpeqb	%xmm1, %xmm2
+	psubb	%xmm0, %xmm2
+	pmovmskb %xmm2, %r9d
+	shr	%cl, %edx
+	shr	%cl, %r9d
+	sub	%r9d, %edx
+	jnz	L(less32bytes)
+	movdqa	(%rdi), %xmm3
+
+	UPDATE_STRNCMP_COUNTER
+
+	pxor	%xmm0, %xmm0
+	mov	$16, %rcx	/* index for loads */
+	mov	$3, %r9d	/* byte position left over from less32bytes case */
+	/*
+	 * Setup %r10 value allows us to detect crossing a page boundary.
+	 * When %r10 goes positive we have crossed a page boundary and
+	 * need to do a nibble.
+	 */
+	lea	3(%rdi), %r10
+	and	$0xfff, %r10	/* offset into 4K page */
+	sub	$0x1000, %r10	/* subtract 4K pagesize */
+
+	.p2align 4
+L(loop_ashr_3):
+	add	$16, %r10
+	jg	L(nibble_ashr_3)
+
+L(gobble_ashr_3):
+	movdqa	(%rsi, %rcx), %xmm1
+	movdqa	(%rdi, %rcx), %xmm2
+	movdqa	%xmm2, %xmm4
+
+	palignr $3, %xmm3, %xmm2        /* merge into one 16byte value */
+
+	pcmpeqb	%xmm1, %xmm0
+	pcmpeqb	%xmm2, %xmm1
+	psubb	%xmm0, %xmm1
+	pmovmskb %xmm1, %edx
+	sub	$0xffff, %edx
+	jnz	L(exit)
+
+#ifdef USE_AS_STRNCMP
+	sub	$16, %r11
+	jbe	L(strcmp_exitz)
+#endif
+
+	add	$16, %rcx
+	movdqa	%xmm4, %xmm3
+
+	add	$16, %r10
+	jg	L(nibble_ashr_3)	/* cross page boundary */
+
+	movdqa	(%rsi, %rcx), %xmm1
+	movdqa	(%rdi, %rcx), %xmm2
+	movdqa	%xmm2, %xmm4
+
+	palignr $3, %xmm3, %xmm2        /* merge into one 16byte value */
+
+	pcmpeqb	%xmm1, %xmm0
+	pcmpeqb	%xmm2, %xmm1
+	psubb	%xmm0, %xmm1
+	pmovmskb %xmm1, %edx
+	sub	$0xffff, %edx
+	jnz	L(exit)
+
+#ifdef USE_AS_STRNCMP
+	sub	$16, %r11
+	jbe	L(strcmp_exitz)
+#endif
+
+	add	$16, %rcx
+	movdqa	%xmm4, %xmm3
+	jmp	L(loop_ashr_3)
+
+	.p2align 4
+L(nibble_ashr_3):
+	pcmpeqb	%xmm3, %xmm0		/* check nibble for null char */
+	pmovmskb %xmm0, %edx
+	test	$0xfff8, %edx
+	jnz	L(ashr_3_exittail)
+
+#ifdef USE_AS_STRNCMP
+	cmp	$12, %r11
+	jbe	L(ashr_3_exittail)
+#endif
+
+	pxor	%xmm0, %xmm0
+	sub	$0x1000, %r10
+	jmp	L(gobble_ashr_3)
+
+	.p2align 4
+L(ashr_3_exittail):
+	movdqa	(%rsi, %rcx), %xmm1
+	psrldq	$3, %xmm0
+	psrldq	$3, %xmm3
+	jmp	L(aftertail)
+
+/*
+ * The following cases will be handled by ashr_4
+ *  rcx(offset of rsi)  rax(offset of rdi)  relative offset	 corresponding case
+ *        n(12~15)            n -12         3(15 +(n-12) - n)         ashr_4
+ */
+	.p2align 4
+L(ashr_4):
+	pxor	%xmm0, %xmm0
+	movdqa	(%rdi), %xmm2
+	movdqa	(%rsi), %xmm1
+	pcmpeqb	%xmm1, %xmm0
+	pslldq	$12, %xmm2
+	pcmpeqb	%xmm1, %xmm2
+	psubb	%xmm0, %xmm2
+	pmovmskb %xmm2, %r9d
+	shr	%cl, %edx
+	shr	%cl, %r9d
+	sub	%r9d, %edx
+	jnz	L(less32bytes)
+	movdqa	(%rdi), %xmm3
+
+	UPDATE_STRNCMP_COUNTER
+
+	pxor	%xmm0, %xmm0
+	mov	$16, %rcx	/* index for loads */
+	mov	$4, %r9d	/* byte position left over from less32bytes case */
+	/*
+	 * Setup %r10 value allows us to detect crossing a page boundary.
+	 * When %r10 goes positive we have crossed a page boundary and
+	 * need to do a nibble.
+	 */
+	lea	4(%rdi), %r10
+	and	$0xfff, %r10	/* offset into 4K page */
+	sub	$0x1000, %r10	/* subtract 4K pagesize */
+
+	.p2align 4
+L(loop_ashr_4):
+	add	$16, %r10
+	jg	L(nibble_ashr_4)
+
+L(gobble_ashr_4):
+	movdqa	(%rsi, %rcx), %xmm1
+	movdqa	(%rdi, %rcx), %xmm2
+	movdqa	%xmm2, %xmm4
+
+	palignr $4, %xmm3, %xmm2        /* merge into one 16byte value */
+
+	pcmpeqb	%xmm1, %xmm0
+	pcmpeqb	%xmm2, %xmm1
+	psubb	%xmm0, %xmm1
+	pmovmskb %xmm1, %edx
+	sub	$0xffff, %edx
+	jnz	L(exit)
+
+#ifdef USE_AS_STRNCMP
+	sub	$16, %r11
+	jbe	L(strcmp_exitz)
+#endif
+
+	add	$16, %rcx
+	movdqa	%xmm4, %xmm3
+
+	add	$16, %r10
+	jg	L(nibble_ashr_4)	/* cross page boundary */
+
+	movdqa	(%rsi, %rcx), %xmm1
+	movdqa	(%rdi, %rcx), %xmm2
+	movdqa	%xmm2, %xmm4
+
+	palignr $4, %xmm3, %xmm2        /* merge into one 16byte value */
+
+	pcmpeqb	%xmm1, %xmm0
+	pcmpeqb	%xmm2, %xmm1
+	psubb	%xmm0, %xmm1
+	pmovmskb %xmm1, %edx
+	sub	$0xffff, %edx
+	jnz	L(exit)
+
+#ifdef USE_AS_STRNCMP
+	sub	$16, %r11
+	jbe	L(strcmp_exitz)
+#endif
+
+	add	$16, %rcx
+	movdqa	%xmm4, %xmm3
+	jmp	L(loop_ashr_4)
+
+	.p2align 4
+L(nibble_ashr_4):
+	pcmpeqb	%xmm3, %xmm0		/* check nibble for null char */
+	pmovmskb %xmm0, %edx
+	test	$0xfff0, %edx
+	jnz	L(ashr_4_exittail)
+
+#ifdef USE_AS_STRNCMP
+	cmp	$11, %r11
+	jbe	L(ashr_4_exittail)
+#endif
+
+	pxor	%xmm0, %xmm0
+	sub	$0x1000, %r10
+	jmp	L(gobble_ashr_4)
+
+	.p2align 4
+L(ashr_4_exittail):
+	movdqa	(%rsi, %rcx), %xmm1
+	psrldq	$4, %xmm0
+	psrldq	$4, %xmm3
+	jmp	L(aftertail)
+
+/*
+ * The following cases will be handled by ashr_5
+ *  rcx(offset of rsi)  rax(offset of rdi)        relative offset      corresponding case
+ *        n(11~15)          n - 11      	  4(15 +(n-11) - n)         ashr_5
+ */
+	.p2align 4
+L(ashr_5):
+	pxor	%xmm0, %xmm0
+	movdqa	(%rdi), %xmm2
+	movdqa	(%rsi), %xmm1
+	pcmpeqb	%xmm1, %xmm0
+	pslldq	$11, %xmm2
+	pcmpeqb	%xmm1, %xmm2
+	psubb	%xmm0, %xmm2
+	pmovmskb %xmm2, %r9d
+	shr	%cl, %edx
+	shr	%cl, %r9d
+	sub	%r9d, %edx
+	jnz	L(less32bytes)
+	movdqa	(%rdi), %xmm3
+
+	UPDATE_STRNCMP_COUNTER
+
+	pxor	%xmm0, %xmm0
+	mov	$16, %rcx	/* index for loads */
+	mov	$5, %r9d	/* byte position left over from less32bytes case */
+	/*
+	 * Setup %r10 value allows us to detect crossing a page boundary.
+	 * When %r10 goes positive we have crossed a page boundary and
+	 * need to do a nibble.
+	 */
+	lea	5(%rdi), %r10
+	and	$0xfff, %r10	/* offset into 4K page */
+	sub	$0x1000, %r10	/* subtract 4K pagesize */
+
+	.p2align 4
+L(loop_ashr_5):
+	add	$16, %r10
+	jg	L(nibble_ashr_5)
+
+L(gobble_ashr_5):
+	movdqa	(%rsi, %rcx), %xmm1
+	movdqa	(%rdi, %rcx), %xmm2
+	movdqa	%xmm2, %xmm4
+
+	palignr $5, %xmm3, %xmm2        /* merge into one 16byte value */
+
+	pcmpeqb	%xmm1, %xmm0
+	pcmpeqb	%xmm2, %xmm1
+	psubb	%xmm0, %xmm1
+	pmovmskb %xmm1, %edx
+	sub	$0xffff, %edx
+	jnz	L(exit)
+
+#ifdef USE_AS_STRNCMP
+	sub	$16, %r11
+	jbe	L(strcmp_exitz)
+#endif
+
+	add	$16, %rcx
+	movdqa	%xmm4, %xmm3
+
+	add	$16, %r10
+	jg	L(nibble_ashr_5)	/* cross page boundary */
+
+	movdqa	(%rsi, %rcx), %xmm1
+	movdqa	(%rdi, %rcx), %xmm2
+	movdqa	%xmm2, %xmm4
+
+	palignr $5, %xmm3, %xmm2        /* merge into one 16byte value */
+
+	pcmpeqb	%xmm1, %xmm0
+	pcmpeqb	%xmm2, %xmm1
+	psubb	%xmm0, %xmm1
+	pmovmskb %xmm1, %edx
+	sub	$0xffff, %edx
+	jnz	L(exit)
+
+#ifdef USE_AS_STRNCMP
+	sub	$16, %r11
+	jbe	L(strcmp_exitz)
+#endif
+
+	add	$16, %rcx
+	movdqa	%xmm4, %xmm3
+	jmp	L(loop_ashr_5)
+
+	.p2align 4
+L(nibble_ashr_5):
+	pcmpeqb	%xmm3, %xmm0		/* check nibble for null char */
+	pmovmskb %xmm0, %edx
+	test	$0xffe0, %edx
+	jnz	L(ashr_5_exittail)
+
+#ifdef USE_AS_STRNCMP
+	cmp	$10, %r11
+	jbe	L(ashr_5_exittail)
+#endif
+
+	pxor	%xmm0, %xmm0
+	sub	$0x1000, %r10
+	jmp	L(gobble_ashr_5)
+
+	.p2align 4
+L(ashr_5_exittail):
+	movdqa	(%rsi, %rcx), %xmm1
+	psrldq	$5, %xmm0
+	psrldq	$5, %xmm3
+	jmp	L(aftertail)
+
+/*
+ * The following cases will be handled by ashr_6
+ *  rcx(offset of rsi)  rax(offset of rdi)        relative offset      corresponding case
+ *        n(10~15)          n - 10      	  5(15 +(n-10) - n)         ashr_6
+ */
+	.p2align 4
+L(ashr_6):
+	pxor	%xmm0, %xmm0
+	movdqa	(%rdi), %xmm2
+	movdqa	(%rsi), %xmm1
+	pcmpeqb	%xmm1, %xmm0
+	pslldq	$10, %xmm2
+	pcmpeqb	%xmm1, %xmm2
+	psubb	%xmm0, %xmm2
+	pmovmskb %xmm2, %r9d
+	shr	%cl, %edx
+	shr	%cl, %r9d
+	sub	%r9d, %edx
+	jnz	L(less32bytes)
+	movdqa	(%rdi), %xmm3
+
+	UPDATE_STRNCMP_COUNTER
+
+	pxor	%xmm0, %xmm0
+	mov	$16, %rcx	/* index for loads */
+	mov	$6, %r9d	/* byte position left over from less32bytes case */
+	/*
+	 * Setup %r10 value allows us to detect crossing a page boundary.
+	 * When %r10 goes positive we have crossed a page boundary and
+	 * need to do a nibble.
+	 */
+	lea	6(%rdi), %r10
+	and	$0xfff, %r10	/* offset into 4K page */
+	sub	$0x1000, %r10	/* subtract 4K pagesize */
+
+	.p2align 4
+L(loop_ashr_6):
+	add	$16, %r10
+	jg	L(nibble_ashr_6)
+
+L(gobble_ashr_6):
+	movdqa	(%rsi, %rcx), %xmm1
+	movdqa	(%rdi, %rcx), %xmm2
+	movdqa	%xmm2, %xmm4
+
+	palignr $6, %xmm3, %xmm2        /* merge into one 16byte value */
+
+	pcmpeqb	%xmm1, %xmm0
+	pcmpeqb	%xmm2, %xmm1
+	psubb	%xmm0, %xmm1
+	pmovmskb %xmm1, %edx
+	sub	$0xffff, %edx
+	jnz	L(exit)
+
+#ifdef USE_AS_STRNCMP
+	sub	$16, %r11
+	jbe	L(strcmp_exitz)
+#endif
+
+	add	$16, %rcx
+	movdqa	%xmm4, %xmm3
+
+	add	$16, %r10
+	jg	L(nibble_ashr_6)	/* cross page boundary */
+
+	movdqa	(%rsi, %rcx), %xmm1
+	movdqa	(%rdi, %rcx), %xmm2
+	movdqa	%xmm2, %xmm4
+
+	palignr $6, %xmm3, %xmm2        /* merge into one 16byte value */
+
+	pcmpeqb	%xmm1, %xmm0
+	pcmpeqb	%xmm2, %xmm1
+	psubb	%xmm0, %xmm1
+	pmovmskb %xmm1, %edx
+	sub	$0xffff, %edx
+	jnz	L(exit)
+
+#ifdef USE_AS_STRNCMP
+	sub	$16, %r11
+	jbe	L(strcmp_exitz)
+#endif
+
+	add	$16, %rcx
+	movdqa	%xmm4, %xmm3
+	jmp	L(loop_ashr_6)
+
+	.p2align 4
+L(nibble_ashr_6):
+	pcmpeqb	%xmm3, %xmm0		/* check nibble for null char */
+	pmovmskb %xmm0, %edx
+	test	$0xffc0, %edx
+	jnz	L(ashr_6_exittail)
+
+#ifdef USE_AS_STRNCMP
+	cmp	$9, %r11
+	jbe	L(ashr_6_exittail)
+#endif
+
+	pxor	%xmm0, %xmm0
+	sub	$0x1000, %r10
+	jmp	L(gobble_ashr_6)
+
+	.p2align 4
+L(ashr_6_exittail):
+	movdqa	(%rsi, %rcx), %xmm1
+	psrldq	$6, %xmm0
+	psrldq	$6, %xmm3
+	jmp	L(aftertail)
+
+/*
+ * The following cases will be handled by ashr_7
+ *  rcx(offset of rsi)  rax(offset of rdi)        relative offset      corresponding case
+ *        n(9~15)          n - 9      	        6(15 +(n - 9) - n)         ashr_7
+ */
+	.p2align 4
+L(ashr_7):
+	pxor	%xmm0, %xmm0
+	movdqa	(%rdi), %xmm2
+	movdqa	(%rsi), %xmm1
+	pcmpeqb	%xmm1, %xmm0
+	pslldq	$9, %xmm2
+	pcmpeqb	%xmm1, %xmm2
+	psubb	%xmm0, %xmm2
+	pmovmskb %xmm2, %r9d
+	shr	%cl, %edx
+	shr	%cl, %r9d
+	sub	%r9d, %edx
+	jnz	L(less32bytes)
+	movdqa	(%rdi), %xmm3
+
+	UPDATE_STRNCMP_COUNTER
+
+	pxor	%xmm0, %xmm0
+	mov	$16, %rcx	/* index for loads */
+	mov	$7, %r9d	/* byte position left over from less32bytes case */
+	/*
+	 * Setup %r10 value allows us to detect crossing a page boundary.
+	 * When %r10 goes positive we have crossed a page boundary and
+	 * need to do a nibble.
+	 */
+	lea	7(%rdi), %r10
+	and	$0xfff, %r10	/* offset into 4K page */
+	sub	$0x1000, %r10	/* subtract 4K pagesize */
+
+	.p2align 4
+L(loop_ashr_7):
+	add	$16, %r10
+	jg	L(nibble_ashr_7)
+
+L(gobble_ashr_7):
+	movdqa	(%rsi, %rcx), %xmm1
+	movdqa	(%rdi, %rcx), %xmm2
+	movdqa	%xmm2, %xmm4
+
+	palignr $7, %xmm3, %xmm2        /* merge into one 16byte value */
+
+	pcmpeqb	%xmm1, %xmm0
+	pcmpeqb	%xmm2, %xmm1
+	psubb	%xmm0, %xmm1
+	pmovmskb %xmm1, %edx
+	sub	$0xffff, %edx
+	jnz	L(exit)
+
+#ifdef USE_AS_STRNCMP
+	sub	$16, %r11
+	jbe	L(strcmp_exitz)
+#endif
+
+	add	$16, %rcx
+	movdqa	%xmm4, %xmm3
+
+	add	$16, %r10
+	jg	L(nibble_ashr_7)	/* cross page boundary */
+
+	movdqa	(%rsi, %rcx), %xmm1
+	movdqa	(%rdi, %rcx), %xmm2
+	movdqa	%xmm2, %xmm4
+
+	palignr $7, %xmm3, %xmm2        /* merge into one 16byte value */
+
+	pcmpeqb	%xmm1, %xmm0
+	pcmpeqb	%xmm2, %xmm1
+	psubb	%xmm0, %xmm1
+	pmovmskb %xmm1, %edx
+	sub	$0xffff, %edx
+	jnz	L(exit)
+
+#ifdef USE_AS_STRNCMP
+	sub	$16, %r11
+	jbe	L(strcmp_exitz)
+#endif
+
+	add	$16, %rcx
+	movdqa	%xmm4, %xmm3
+	jmp	L(loop_ashr_7)
+
+	.p2align 4
+L(nibble_ashr_7):
+	pcmpeqb	%xmm3, %xmm0		/* check nibble for null char */
+	pmovmskb %xmm0, %edx
+	test	$0xff80, %edx
+	jnz	L(ashr_7_exittail)
+
+#ifdef USE_AS_STRNCMP
+	cmp	$8, %r11
+	jbe	L(ashr_7_exittail)
+#endif
+
+	pxor	%xmm0, %xmm0
+	sub	$0x1000, %r10
+	jmp	L(gobble_ashr_7)
+
+	.p2align 4
+L(ashr_7_exittail):
+	movdqa	(%rsi, %rcx), %xmm1
+	psrldq	$7, %xmm0
+	psrldq	$7, %xmm3
+	jmp	L(aftertail)
+
+/*
+ *  The following cases will be handled by ashr_8
+ *  rcx(offset of rsi)  rax(offset of rdi)        relative offset	 corresponding case
+ *        n(8~15)          n - 8      	        7(15 +(n - 8) - n)         ashr_8
+ */
+	.p2align 4
+L(ashr_8):
+	pxor	%xmm0, %xmm0
+	movdqa	(%rdi), %xmm2
+	movdqa	(%rsi), %xmm1
+	pcmpeqb	%xmm1, %xmm0
+	pslldq	$8, %xmm2
+	pcmpeqb	%xmm1, %xmm2
+	psubb	%xmm0, %xmm2
+	pmovmskb %xmm2, %r9d
+	shr	%cl, %edx
+	shr	%cl, %r9d
+	sub	%r9d, %edx
+	jnz	L(less32bytes)
+	movdqa	(%rdi), %xmm3
+
+	UPDATE_STRNCMP_COUNTER
+
+	pxor	%xmm0, %xmm0
+	mov	$16, %rcx	/* index for loads */
+	mov	$8, %r9d	/* byte position left over from less32bytes case */
+	/*
+	 * Setup %r10 value allows us to detect crossing a page boundary.
+	 * When %r10 goes positive we have crossed a page boundary and
+	 * need to do a nibble.
+	 */
+	lea	8(%rdi), %r10
+	and	$0xfff, %r10	/* offset into 4K page */
+	sub	$0x1000, %r10	/* subtract 4K pagesize */
+
+	.p2align 4
+L(loop_ashr_8):
+	add	$16, %r10
+	jg	L(nibble_ashr_8)
+
+L(gobble_ashr_8):
+	movdqa	(%rsi, %rcx), %xmm1
+	movdqa	(%rdi, %rcx), %xmm2
+	movdqa	%xmm2, %xmm4
+
+	palignr $8, %xmm3, %xmm2        /* merge into one 16byte value */
+
+	pcmpeqb	%xmm1, %xmm0
+	pcmpeqb	%xmm2, %xmm1
+	psubb	%xmm0, %xmm1
+	pmovmskb %xmm1, %edx
+	sub	$0xffff, %edx
+	jnz	L(exit)
+
+#ifdef USE_AS_STRNCMP
+	sub	$16, %r11
+	jbe	L(strcmp_exitz)
+#endif
+
+	add	$16, %rcx
+	movdqa	%xmm4, %xmm3
+
+	add	$16, %r10
+	jg	L(nibble_ashr_8)	/* cross page boundary */
+
+	movdqa	(%rsi, %rcx), %xmm1
+	movdqa	(%rdi, %rcx), %xmm2
+	movdqa	%xmm2, %xmm4
+
+	palignr $8, %xmm3, %xmm2        /* merge into one 16byte value */
+
+	pcmpeqb	%xmm1, %xmm0
+	pcmpeqb	%xmm2, %xmm1
+	psubb	%xmm0, %xmm1
+	pmovmskb %xmm1, %edx
+	sub	$0xffff, %edx
+	jnz	L(exit)
+
+#ifdef USE_AS_STRNCMP
+	sub	$16, %r11
+	jbe	L(strcmp_exitz)
+#endif
+
+	add	$16, %rcx
+	movdqa	%xmm4, %xmm3
+	jmp	L(loop_ashr_8)
+
+	.p2align 4
+L(nibble_ashr_8):
+	pcmpeqb	%xmm3, %xmm0		/* check nibble for null char */
+	pmovmskb %xmm0, %edx
+	test	$0xff00, %edx
+	jnz	L(ashr_8_exittail)
+
+#ifdef USE_AS_STRNCMP
+	cmp	$7, %r11
+	jbe	L(ashr_8_exittail)
+#endif
+
+	pxor	%xmm0, %xmm0
+	sub	$0x1000, %r10
+	jmp	L(gobble_ashr_8)
+
+	.p2align 4
+L(ashr_8_exittail):
+	movdqa	(%rsi, %rcx), %xmm1
+	psrldq	$8, %xmm0
+	psrldq	$8, %xmm3
+	jmp	L(aftertail)
+
+/*
+ *  The following cases will be handled by ashr_9
+ *  rcx(offset of rsi)  rax(offset of rdi)        relative offset	 corresponding case
+ *        n(7~15)          n - 7      	        8(15 +(n - 7) - n)         ashr_9
+ */
+	.p2align 4
+L(ashr_9):
+	pxor	%xmm0, %xmm0
+	movdqa	(%rdi), %xmm2
+	movdqa	(%rsi), %xmm1
+	pcmpeqb	%xmm1, %xmm0
+	pslldq	$7, %xmm2
+	pcmpeqb	%xmm1, %xmm2
+	psubb	%xmm0, %xmm2
+	pmovmskb %xmm2, %r9d
+	shr	%cl, %edx
+	shr	%cl, %r9d
+	sub	%r9d, %edx
+	jnz	L(less32bytes)
+	movdqa	(%rdi), %xmm3
+
+	UPDATE_STRNCMP_COUNTER
+
+	pxor	%xmm0, %xmm0
+	mov	$16, %rcx	/* index for loads */
+	mov	$9, %r9d	/* byte position left over from less32bytes case */
+	/*
+	 * Setup %r10 value allows us to detect crossing a page boundary.
+	 * When %r10 goes positive we have crossed a page boundary and
+	 * need to do a nibble.
+	 */
+	lea	9(%rdi), %r10
+	and	$0xfff, %r10	/* offset into 4K page */
+	sub	$0x1000, %r10	/* subtract 4K pagesize */
+
+	.p2align 4
+L(loop_ashr_9):
+	add	$16, %r10
+	jg	L(nibble_ashr_9)
+
+L(gobble_ashr_9):
+	movdqa	(%rsi, %rcx), %xmm1
+	movdqa	(%rdi, %rcx), %xmm2
+	movdqa	%xmm2, %xmm4
+
+	palignr $9, %xmm3, %xmm2        /* merge into one 16byte value */
+
+	pcmpeqb	%xmm1, %xmm0
+	pcmpeqb	%xmm2, %xmm1
+	psubb	%xmm0, %xmm1
+	pmovmskb %xmm1, %edx
+	sub	$0xffff, %edx
+	jnz	L(exit)
+
+#ifdef USE_AS_STRNCMP
+	sub	$16, %r11
+	jbe	L(strcmp_exitz)
+#endif
+
+	add	$16, %rcx
+	movdqa	%xmm4, %xmm3
+
+	add	$16, %r10
+	jg	L(nibble_ashr_9)	/* cross page boundary */
+
+	movdqa	(%rsi, %rcx), %xmm1
+	movdqa	(%rdi, %rcx), %xmm2
+	movdqa	%xmm2, %xmm4
+
+	palignr $9, %xmm3, %xmm2        /* merge into one 16byte value */
+
+	pcmpeqb	%xmm1, %xmm0
+	pcmpeqb	%xmm2, %xmm1
+	psubb	%xmm0, %xmm1
+	pmovmskb %xmm1, %edx
+	sub	$0xffff, %edx
+	jnz	L(exit)
+
+#ifdef USE_AS_STRNCMP
+	sub	$16, %r11
+	jbe	L(strcmp_exitz)
+#endif
+
+	add	$16, %rcx
+	movdqa	%xmm4, %xmm3		/* store for next cycle */
+	jmp	L(loop_ashr_9)
+
+	.p2align 4
+L(nibble_ashr_9):
+	pcmpeqb	%xmm3, %xmm0		/* check nibble for null char */
+	pmovmskb %xmm0, %edx
+	test	$0xfe00, %edx
+	jnz	L(ashr_9_exittail)
+
+#ifdef USE_AS_STRNCMP
+	cmp	$6, %r11
+	jbe	L(ashr_9_exittail)
+#endif
+
+	pxor	%xmm0, %xmm0
+	sub	$0x1000, %r10
+	jmp	L(gobble_ashr_9)
+
+	.p2align 4
+L(ashr_9_exittail):
+	movdqa	(%rsi, %rcx), %xmm1
+	psrldq	$9, %xmm0
+	psrldq	$9, %xmm3
+	jmp	L(aftertail)
+
+/*
+ *  The following cases will be handled by ashr_10
+ *  rcx(offset of rsi)  rax(offset of rdi)        relative offset	 corresponding case
+ *        n(6~15)          n - 6      	        9(15 +(n - 6) - n)         ashr_10
+ */
+	.p2align 4
+L(ashr_10):
+	pxor	%xmm0, %xmm0
+	movdqa	(%rdi), %xmm2
+	movdqa	(%rsi), %xmm1
+	pcmpeqb	%xmm1, %xmm0
+	pslldq	$6, %xmm2
+	pcmpeqb	%xmm1, %xmm2
+	psubb	%xmm0, %xmm2
+	pmovmskb %xmm2, %r9d
+	shr	%cl, %edx
+	shr	%cl, %r9d
+	sub	%r9d, %edx
+	jnz	L(less32bytes)
+	movdqa	(%rdi), %xmm3
+
+	UPDATE_STRNCMP_COUNTER
+
+	pxor	%xmm0, %xmm0
+	mov	$16, %rcx	/* index for loads */
+	mov	$10, %r9d	/* byte position left over from less32bytes case */
+	/*
+	 * Setup %r10 value allows us to detect crossing a page boundary.
+	 * When %r10 goes positive we have crossed a page boundary and
+	 * need to do a nibble.
+	 */
+	lea	10(%rdi), %r10
+	and	$0xfff, %r10	/* offset into 4K page */
+	sub	$0x1000, %r10	/* subtract 4K pagesize */
+
+	.p2align 4
+L(loop_ashr_10):
+	add	$16, %r10
+	jg	L(nibble_ashr_10)
+
+L(gobble_ashr_10):
+	movdqa	(%rsi, %rcx), %xmm1
+	movdqa	(%rdi, %rcx), %xmm2
+	movdqa	%xmm2, %xmm4
+
+	palignr $10, %xmm3, %xmm2        /* merge into one 16byte value */
+
+	pcmpeqb	%xmm1, %xmm0
+	pcmpeqb	%xmm2, %xmm1
+	psubb	%xmm0, %xmm1
+	pmovmskb %xmm1, %edx
+	sub	$0xffff, %edx
+	jnz	L(exit)
+
+#ifdef USE_AS_STRNCMP
+	sub	$16, %r11
+	jbe	L(strcmp_exitz)
+#endif
+
+	add	$16, %rcx
+	movdqa	%xmm4, %xmm3
+
+	add	$16, %r10
+	jg	L(nibble_ashr_10)	/* cross page boundary */
+
+	movdqa	(%rsi, %rcx), %xmm1
+	movdqa	(%rdi, %rcx), %xmm2
+	movdqa	%xmm2, %xmm4
+
+	palignr $10, %xmm3, %xmm2        /* merge into one 16byte value */
+
+	pcmpeqb	%xmm1, %xmm0
+	pcmpeqb	%xmm2, %xmm1
+	psubb	%xmm0, %xmm1
+	pmovmskb %xmm1, %edx
+	sub	$0xffff, %edx
+	jnz	L(exit)
+
+#ifdef USE_AS_STRNCMP
+	sub	$16, %r11
+	jbe	L(strcmp_exitz)
+#endif
+
+	add	$16, %rcx
+	movdqa	%xmm4, %xmm3
+	jmp	L(loop_ashr_10)
+
+	.p2align 4
+L(nibble_ashr_10):
+	pcmpeqb	%xmm3, %xmm0		/* check nibble for null char */
+	pmovmskb %xmm0, %edx
+	test	$0xfc00, %edx
+	jnz	L(ashr_10_exittail)
+
+#ifdef USE_AS_STRNCMP
+	cmp	$5, %r11
+	jbe	L(ashr_10_exittail)
+#endif
+
+	pxor	%xmm0, %xmm0
+	sub	$0x1000, %r10
+	jmp	L(gobble_ashr_10)
+
+	.p2align 4
+L(ashr_10_exittail):
+	movdqa	(%rsi, %rcx), %xmm1
+	psrldq	$10, %xmm0
+	psrldq	$10, %xmm3
+	jmp	L(aftertail)
+
+/*
+ *  The following cases will be handled by ashr_11
+ *  rcx(offset of rsi)  rax(offset of rdi)        relative offset	 corresponding case
+ *        n(5~15)          n - 5      	        10(15 +(n - 5) - n)         ashr_11
+ */
+	.p2align 4
+L(ashr_11):
+	pxor	%xmm0, %xmm0
+	movdqa	(%rdi), %xmm2
+	movdqa	(%rsi), %xmm1
+	pcmpeqb	%xmm1, %xmm0
+	pslldq	$5, %xmm2
+	pcmpeqb	%xmm1, %xmm2
+	psubb	%xmm0, %xmm2
+	pmovmskb %xmm2, %r9d
+	shr	%cl, %edx
+	shr	%cl, %r9d
+	sub	%r9d, %edx
+	jnz	L(less32bytes)
+	movdqa	(%rdi), %xmm3
+
+	UPDATE_STRNCMP_COUNTER
+
+	pxor	%xmm0, %xmm0
+	mov	$16, %rcx	/* index for loads */
+	mov	$11, %r9d	/* byte position left over from less32bytes case */
+	/*
+	 * Setup %r10 value allows us to detect crossing a page boundary.
+	 * When %r10 goes positive we have crossed a page boundary and
+	 * need to do a nibble.
+	 */
+	lea	11(%rdi), %r10
+	and	$0xfff, %r10	/* offset into 4K page */
+	sub	$0x1000, %r10	/* subtract 4K pagesize */
+
+	.p2align 4
+L(loop_ashr_11):
+	add	$16, %r10
+	jg	L(nibble_ashr_11)
+
+L(gobble_ashr_11):
+	movdqa	(%rsi, %rcx), %xmm1
+	movdqa	(%rdi, %rcx), %xmm2
+	movdqa	%xmm2, %xmm4
+
+	palignr $11, %xmm3, %xmm2        /* merge into one 16byte value */
+
+	pcmpeqb	%xmm1, %xmm0
+	pcmpeqb	%xmm2, %xmm1
+	psubb	%xmm0, %xmm1
+	pmovmskb %xmm1, %edx
+	sub	$0xffff, %edx
+	jnz	L(exit)
+
+#ifdef USE_AS_STRNCMP
+	sub	$16, %r11
+	jbe	L(strcmp_exitz)
+#endif
+
+	add	$16, %rcx
+	movdqa	%xmm4, %xmm3
+
+	add	$16, %r10
+	jg	L(nibble_ashr_11)	/* cross page boundary */
+
+	movdqa	(%rsi, %rcx), %xmm1
+	movdqa	(%rdi, %rcx), %xmm2
+	movdqa	%xmm2, %xmm4
+
+	palignr $11, %xmm3, %xmm2        /* merge into one 16byte value */
+
+	pcmpeqb	%xmm1, %xmm0
+	pcmpeqb	%xmm2, %xmm1
+	psubb	%xmm0, %xmm1
+	pmovmskb %xmm1, %edx
+	sub	$0xffff, %edx
+	jnz	L(exit)
+
+#ifdef USE_AS_STRNCMP
+	sub	$16, %r11
+	jbe	L(strcmp_exitz)
+#endif
+
+	add	$16, %rcx
+	movdqa	%xmm4, %xmm3
+	jmp	L(loop_ashr_11)
+
+	.p2align 4
+L(nibble_ashr_11):
+	pcmpeqb	%xmm3, %xmm0		/* check nibble for null char */
+	pmovmskb %xmm0, %edx
+	test	$0xf800, %edx
+	jnz	L(ashr_11_exittail)
+
+#ifdef USE_AS_STRNCMP
+	cmp	$4, %r11
+	jbe	L(ashr_11_exittail)
+#endif
+
+	pxor	%xmm0, %xmm0
+	sub	$0x1000, %r10
+	jmp	L(gobble_ashr_11)
+
+	.p2align 4
+L(ashr_11_exittail):
+	movdqa	(%rsi, %rcx), %xmm1
+	psrldq	$11, %xmm0
+	psrldq	$11, %xmm3
+	jmp	L(aftertail)
+
+/*
+ *  The following cases will be handled by ashr_12
+ *  rcx(offset of rsi)  rax(offset of rdi)        relative offset	 corresponding case
+ *        n(4~15)          n - 4      	        11(15 +(n - 4) - n)         ashr_12
+ */
+	.p2align 4
+L(ashr_12):
+	pxor	%xmm0, %xmm0
+	movdqa	(%rdi), %xmm2
+	movdqa	(%rsi), %xmm1
+	pcmpeqb	%xmm1, %xmm0
+	pslldq	$4, %xmm2
+	pcmpeqb	%xmm1, %xmm2
+	psubb	%xmm0, %xmm2
+	pmovmskb %xmm2, %r9d
+	shr	%cl, %edx
+	shr	%cl, %r9d
+	sub	%r9d, %edx
+	jnz	L(less32bytes)
+	movdqa	(%rdi), %xmm3
+
+	UPDATE_STRNCMP_COUNTER
+
+	pxor	%xmm0, %xmm0
+	mov	$16, %rcx	/* index for loads */
+	mov	$12, %r9d	/* byte position left over from less32bytes case */
+	/*
+	 * Setup %r10 value allows us to detect crossing a page boundary.
+	 * When %r10 goes positive we have crossed a page boundary and
+	 * need to do a nibble.
+	 */
+	lea	12(%rdi), %r10
+	and	$0xfff, %r10	/* offset into 4K page */
+	sub	$0x1000, %r10	/* subtract 4K pagesize */
+
+	.p2align 4
+L(loop_ashr_12):
+	add	$16, %r10
+	jg	L(nibble_ashr_12)
+
+L(gobble_ashr_12):
+	movdqa	(%rsi, %rcx), %xmm1
+	movdqa	(%rdi, %rcx), %xmm2
+	movdqa	%xmm2, %xmm4
+
+	palignr $12, %xmm3, %xmm2        /* merge into one 16byte value */
+
+	pcmpeqb	%xmm1, %xmm0
+	pcmpeqb	%xmm2, %xmm1
+	psubb	%xmm0, %xmm1
+	pmovmskb %xmm1, %edx
+	sub	$0xffff, %edx
+	jnz	L(exit)
+
+#ifdef USE_AS_STRNCMP
+	sub	$16, %r11
+	jbe	L(strcmp_exitz)
+#endif
+
+	add	$16, %rcx
+	movdqa	%xmm4, %xmm3
+
+	add	$16, %r10
+	jg	L(nibble_ashr_12)	/* cross page boundary */
+
+	movdqa	(%rsi, %rcx), %xmm1
+	movdqa	(%rdi, %rcx), %xmm2
+	movdqa	%xmm2, %xmm4
+
+	palignr $12, %xmm3, %xmm2        /* merge into one 16byte value */
+
+	pcmpeqb	%xmm1, %xmm0
+	pcmpeqb	%xmm2, %xmm1
+	psubb	%xmm0, %xmm1
+	pmovmskb %xmm1, %edx
+	sub	$0xffff, %edx
+	jnz	L(exit)
+
+#ifdef USE_AS_STRNCMP
+	sub	$16, %r11
+	jbe	L(strcmp_exitz)
+#endif
+
+	add	$16, %rcx
+	movdqa	%xmm4, %xmm3
+	jmp	L(loop_ashr_12)
+
+	.p2align 4
+L(nibble_ashr_12):
+	pcmpeqb	%xmm3, %xmm0		/* check nibble for null char */
+	pmovmskb %xmm0, %edx
+	test	$0xf000, %edx
+	jnz	L(ashr_12_exittail)
+
+#ifdef USE_AS_STRNCMP
+	cmp	$3, %r11
+	jbe	L(ashr_12_exittail)
+#endif
+
+	pxor	%xmm0, %xmm0
+	sub	$0x1000, %r10
+	jmp	L(gobble_ashr_12)
+
+	.p2align 4
+L(ashr_12_exittail):
+	movdqa	(%rsi, %rcx), %xmm1
+	psrldq	$12, %xmm0
+	psrldq	$12, %xmm3
+	jmp	L(aftertail)
+
+/*
+ *  The following cases will be handled by ashr_13
+ *  rcx(offset of rsi)  rax(offset of rdi)        relative offset	 corresponding case
+ *        n(3~15)          n - 3      	        12(15 +(n - 3) - n)         ashr_13
+ */
+	.p2align 4
+L(ashr_13):
+	pxor	%xmm0, %xmm0
+	movdqa	(%rdi), %xmm2
+	movdqa	(%rsi), %xmm1
+	pcmpeqb	%xmm1, %xmm0
+	pslldq	$3, %xmm2
+	pcmpeqb	%xmm1, %xmm2
+	psubb	%xmm0, %xmm2
+	pmovmskb %xmm2, %r9d
+	shr	%cl, %edx
+	shr	%cl, %r9d
+	sub	%r9d, %edx
+	jnz	L(less32bytes)
+	movdqa	(%rdi), %xmm3
+
+	UPDATE_STRNCMP_COUNTER
+
+	pxor	%xmm0, %xmm0
+	mov	$16, %rcx	/* index for loads */
+	mov	$13, %r9d	/* byte position left over from less32bytes case */
+	/*
+	 * Setup %r10 value allows us to detect crossing a page boundary.
+	 * When %r10 goes positive we have crossed a page boundary and
+	 * need to do a nibble.
+	 */
+	lea	13(%rdi), %r10
+	and	$0xfff, %r10	/* offset into 4K page */
+	sub	$0x1000, %r10	/* subtract 4K pagesize */
+
+	.p2align 4
+L(loop_ashr_13):
+	add	$16, %r10
+	jg	L(nibble_ashr_13)
+
+L(gobble_ashr_13):
+	movdqa	(%rsi, %rcx), %xmm1
+	movdqa	(%rdi, %rcx), %xmm2
+	movdqa	%xmm2, %xmm4
+
+	palignr $13, %xmm3, %xmm2        /* merge into one 16byte value */
+
+	pcmpeqb	%xmm1, %xmm0
+	pcmpeqb	%xmm2, %xmm1
+	psubb	%xmm0, %xmm1
+	pmovmskb %xmm1, %edx
+	sub	$0xffff, %edx
+	jnz	L(exit)
+
+#ifdef USE_AS_STRNCMP
+	sub	$16, %r11
+	jbe	L(strcmp_exitz)
+#endif
+
+	add	$16, %rcx
+	movdqa	%xmm4, %xmm3
+
+	add	$16, %r10
+	jg	L(nibble_ashr_13)	/* cross page boundary */
+
+	movdqa	(%rsi, %rcx), %xmm1
+	movdqa	(%rdi, %rcx), %xmm2
+	movdqa	%xmm2, %xmm4
+
+	palignr $13, %xmm3, %xmm2        /* merge into one 16byte value */
+
+	pcmpeqb	%xmm1, %xmm0
+	pcmpeqb	%xmm2, %xmm1
+	psubb	%xmm0, %xmm1
+	pmovmskb %xmm1, %edx
+	sub	$0xffff, %edx
+	jnz	L(exit)
+
+#ifdef USE_AS_STRNCMP
+	sub	$16, %r11
+	jbe	L(strcmp_exitz)
+#endif
+
+	add	$16, %rcx
+	movdqa	%xmm4, %xmm3
+	jmp	L(loop_ashr_13)
+
+	.p2align 4
+L(nibble_ashr_13):
+	pcmpeqb	%xmm3, %xmm0		/* check nibble for null char */
+	pmovmskb %xmm0, %edx
+	test	$0xe000, %edx
+	jnz	L(ashr_13_exittail)
+
+#ifdef USE_AS_STRNCMP
+	cmp	$2, %r11
+	jbe	L(ashr_13_exittail)
+#endif
+
+	pxor	%xmm0, %xmm0
+	sub	$0x1000, %r10
+	jmp	L(gobble_ashr_13)
+
+	.p2align 4
+L(ashr_13_exittail):
+	movdqa	(%rsi, %rcx), %xmm1
+	psrldq  $13, %xmm0
+	psrldq  $13, %xmm3
+	jmp	L(aftertail)
+
+/*
+ *  The following cases will be handled by ashr_14
+ *  rcx(offset of rsi)  rax(offset of rdi)        relative offset	 corresponding case
+ *        n(2~15)          n - 2      	        13(15 +(n - 2) - n)         ashr_14
+ */
+	.p2align 4
+L(ashr_14):
+	pxor	%xmm0, %xmm0
+	movdqa	(%rdi), %xmm2
+	movdqa	(%rsi), %xmm1
+	pcmpeqb	%xmm1, %xmm0
+	pslldq  $2, %xmm2
+	pcmpeqb	%xmm1, %xmm2
+	psubb	%xmm0, %xmm2
+	pmovmskb %xmm2, %r9d
+	shr	%cl, %edx
+	shr	%cl, %r9d
+	sub	%r9d, %edx
+	jnz	L(less32bytes)
+	movdqa	(%rdi), %xmm3
+
+	UPDATE_STRNCMP_COUNTER
+
+	pxor	%xmm0, %xmm0
+	mov	$16, %rcx	/* index for loads */
+	mov	$14, %r9d	/* byte position left over from less32bytes case */
+	/*
+	 * Setup %r10 value allows us to detect crossing a page boundary.
+	 * When %r10 goes positive we have crossed a page boundary and
+	 * need to do a nibble.
+	 */
+	lea	14(%rdi), %r10
+	and	$0xfff, %r10	/* offset into 4K page */
+	sub	$0x1000, %r10	/* subtract 4K pagesize */
+
+	.p2align 4
+L(loop_ashr_14):
+	add	$16, %r10
+	jg	L(nibble_ashr_14)
+
+L(gobble_ashr_14):
+	movdqa	(%rsi, %rcx), %xmm1
+	movdqa	(%rdi, %rcx), %xmm2
+	movdqa	%xmm2, %xmm4
+
+	palignr $14, %xmm3, %xmm2        /* merge into one 16byte value */
+
+	pcmpeqb	%xmm1, %xmm0
+	pcmpeqb	%xmm2, %xmm1
+	psubb	%xmm0, %xmm1
+	pmovmskb %xmm1, %edx
+	sub	$0xffff, %edx
+	jnz	L(exit)
+
+#ifdef USE_AS_STRNCMP
+	sub	$16, %r11
+	jbe	L(strcmp_exitz)
+#endif
+
+	add	$16, %rcx
+	movdqa	%xmm4, %xmm3
+
+	add	$16, %r10
+	jg	L(nibble_ashr_14)	/* cross page boundary */
+
+	movdqa	(%rsi, %rcx), %xmm1
+	movdqa	(%rdi, %rcx), %xmm2
+	movdqa	%xmm2, %xmm4
+
+	palignr $14, %xmm3, %xmm2        /* merge into one 16byte value */
+
+	pcmpeqb	%xmm1, %xmm0
+	pcmpeqb	%xmm2, %xmm1
+	psubb	%xmm0, %xmm1
+	pmovmskb %xmm1, %edx
+	sub	$0xffff, %edx
+	jnz	L(exit)
+
+#ifdef USE_AS_STRNCMP
+	sub	$16, %r11
+	jbe	L(strcmp_exitz)
+#endif
+
+	add	$16, %rcx
+	movdqa	%xmm4, %xmm3
+	jmp	L(loop_ashr_14)
+
+	.p2align 4
+L(nibble_ashr_14):
+	pcmpeqb	%xmm3, %xmm0		/* check nibble for null char */
+	pmovmskb %xmm0, %edx
+	test	$0xc000, %edx
+	jnz	L(ashr_14_exittail)
+
+#ifdef USE_AS_STRNCMP
+	cmp	$1, %r11
+	jbe	L(ashr_14_exittail)
+#endif
+
+	pxor	%xmm0, %xmm0
+	sub	$0x1000, %r10
+	jmp	L(gobble_ashr_14)
+
+	.p2align 4
+L(ashr_14_exittail):
+	movdqa	(%rsi, %rcx), %xmm1
+	psrldq	$14, %xmm0
+	psrldq	$14, %xmm3
+	jmp	L(aftertail)
+
+/*
+ *  The following cases will be handled by ashr_15
+ *  rcx(offset of rsi)  rax(offset of rdi)        relative offset	 corresponding case
+ *        n(1~15)          n - 1      	        14(15 +(n - 1) - n)         ashr_15
+ */
+	.p2align 4
+L(ashr_15):
+	pxor	%xmm0, %xmm0
+	movdqa	(%rdi), %xmm2
+	movdqa	(%rsi), %xmm1
+	pcmpeqb	%xmm1, %xmm0
+	pslldq	$1, %xmm2
+	pcmpeqb	%xmm1, %xmm2
+	psubb	%xmm0, %xmm2
+	pmovmskb %xmm2, %r9d
+	shr	%cl, %edx
+	shr	%cl, %r9d
+	sub	%r9d, %edx
+	jnz	L(less32bytes)
+
+	movdqa	(%rdi), %xmm3
+
+	UPDATE_STRNCMP_COUNTER
+
+	pxor	%xmm0, %xmm0
+	mov	$16, %rcx	/* index for loads */
+	mov	$15, %r9d	/* byte position left over from less32bytes case */
+	/*
+	 * Setup %r10 value allows us to detect crossing a page boundary.
+	 * When %r10 goes positive we have crossed a page boundary and
+	 * need to do a nibble.
+	 */
+	lea	15(%rdi), %r10
+	and	$0xfff, %r10	/* offset into 4K page */
+
+	sub	$0x1000, %r10	/* subtract 4K pagesize */
+
+	.p2align 4
+L(loop_ashr_15):
+	add	$16, %r10
+	jg	L(nibble_ashr_15)
+
+L(gobble_ashr_15):
+	movdqa	(%rsi, %rcx), %xmm1
+	movdqa	(%rdi, %rcx), %xmm2
+	movdqa	%xmm2, %xmm4
+
+	palignr $15, %xmm3, %xmm2        /* merge into one 16byte value */
+
+	pcmpeqb	%xmm1, %xmm0
+	pcmpeqb	%xmm2, %xmm1
+	psubb	%xmm0, %xmm1
+	pmovmskb %xmm1, %edx
+	sub	$0xffff, %edx
+	jnz	L(exit)
+
+#ifdef USE_AS_STRNCMP
+	sub	$16, %r11
+	jbe	L(strcmp_exitz)
+#endif
+
+	add	$16, %rcx
+	movdqa	%xmm4, %xmm3
+
+	add	$16, %r10
+	jg	L(nibble_ashr_15)	/* cross page boundary */
+
+	movdqa	(%rsi, %rcx), %xmm1
+	movdqa	(%rdi, %rcx), %xmm2
+	movdqa	%xmm2, %xmm4
+
+	palignr $15, %xmm3, %xmm2        /* merge into one 16byte value */
+
+	pcmpeqb	%xmm1, %xmm0
+	pcmpeqb	%xmm2, %xmm1
+	psubb	%xmm0, %xmm1
+	pmovmskb %xmm1, %edx
+	sub	$0xffff, %edx
+	jnz	L(exit)
+
+#ifdef USE_AS_STRNCMP
+	sub	$16, %r11
+	jbe	L(strcmp_exitz)
+#endif
+
+	add	$16, %rcx
+	movdqa	%xmm4, %xmm3
+	jmp	L(loop_ashr_15)
+
+	.p2align 4
+L(nibble_ashr_15):
+	pcmpeqb	%xmm3, %xmm0		/* check nibble for null char */
+	pmovmskb %xmm0, %edx
+	test	$0x8000, %edx
+	jnz	L(ashr_15_exittail)
+
+#ifdef USE_AS_STRNCMP
+	test	%r11, %r11
+	je	L(ashr_15_exittail)
+#endif
+
+	pxor	%xmm0, %xmm0
+	sub	$0x1000, %r10
+	jmp	L(gobble_ashr_15)
+
+	.p2align 4
+L(ashr_15_exittail):
+	movdqa	(%rsi, %rcx), %xmm1
+	psrldq	$15, %xmm3
+	psrldq	$15, %xmm0
+
+	.p2align 4
+L(aftertail):
+	pcmpeqb	%xmm3, %xmm1
+	psubb	%xmm0, %xmm1
+	pmovmskb %xmm1, %edx
+	not	%edx
+
+	.p2align 4
+L(exit):
+	lea	-16(%r9, %rcx), %rax	/* locate the exact offset for rdi */
+L(less32bytes):
+	lea	(%rdi, %rax), %rdi	/* locate the exact address for first operand(rdi) */
+	lea	(%rsi, %rcx), %rsi	/* locate the exact address for second operand(rsi) */
+	test	%r8d, %r8d
+	jz	L(ret)
+	xchg	%rsi, %rdi		/* recover original order according to flag(%r8d) */
+
+	.p2align 4
+L(ret):
+L(less16bytes):
+	bsf	%rdx, %rdx		/* find and store bit index in %rdx */
+
+#ifdef USE_AS_STRNCMP
+	sub	%rdx, %r11
+	jbe	L(strcmp_exitz)
+#endif
+	movzbl	(%rsi, %rdx), %ecx
+	movzbl	(%rdi, %rdx), %eax
+
+	sub	%ecx, %eax
+	ret
+
+L(strcmp_exitz):
+	xor	%eax, %eax
+	ret
+
+	.p2align 4
+L(Byte0):
+	movzx	(%rsi), %ecx
+	movzx	(%rdi), %eax
+
+	sub	%ecx, %eax
+	ret
+END (STRCMP)
+
+	.section .rodata,"a",@progbits
+	.p2align 3
+L(unaligned_table):
+	.int	L(ashr_1) - L(unaligned_table)
+	.int	L(ashr_2) - L(unaligned_table)
+	.int	L(ashr_3) - L(unaligned_table)
+	.int	L(ashr_4) - L(unaligned_table)
+	.int	L(ashr_5) - L(unaligned_table)
+	.int	L(ashr_6) - L(unaligned_table)
+	.int	L(ashr_7) - L(unaligned_table)
+	.int	L(ashr_8) - L(unaligned_table)
+	.int	L(ashr_9) - L(unaligned_table)
+	.int	L(ashr_10) - L(unaligned_table)
+	.int	L(ashr_11) - L(unaligned_table)
+	.int	L(ashr_12) - L(unaligned_table)
+	.int	L(ashr_13) - L(unaligned_table)
+	.int	L(ashr_14) - L(unaligned_table)
+	.int	L(ashr_15) - L(unaligned_table)
+	.int	L(ashr_0) - L(unaligned_table)