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authorH.J. Lu <hongjiu.lu@intel.com>2009-07-26 13:32:28 -0700
committerUlrich Drepper <drepper@redhat.com>2009-07-26 13:32:28 -0700
commit7956a3d27c6552f57c8b1c3893d55e501fe30e14 (patch)
tree06f80fd0fd395cfa8cbe282cf5adc97147deb22c /sysdeps/x86_64/strcmp.S
parent7b7f43bed134db6a0da34282fffcbf0af10d4613 (diff)
downloadglibc-7956a3d27c6552f57c8b1c3893d55e501fe30e14.tar.gz
Add SSE2 support to str{,n}cmp for x86-64.
Diffstat (limited to 'sysdeps/x86_64/strcmp.S')
-rw-r--r--sysdeps/x86_64/strcmp.S1948
1 files changed, 1943 insertions, 5 deletions
diff --git a/sysdeps/x86_64/strcmp.S b/sysdeps/x86_64/strcmp.S
index 119b88e40b..340a64ba35 100644
--- a/sysdeps/x86_64/strcmp.S
+++ b/sysdeps/x86_64/strcmp.S
@@ -1,8 +1,10 @@
/* Highly optimized version for x86-64.
- Copyright (C) 1999, 2000, 2002, 2003, 2005 Free Software Foundation, Inc.
+ Copyright (C) 1999, 2000, 2002, 2003, 2005, 2009
+ Free Software Foundation, Inc.
This file is part of the GNU C Library.
Based on i686 version contributed by Ulrich Drepper
<drepper@cygnus.com>, 1999.
+ Updated with SSE2 support contributed by Intel Corporation.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
@@ -24,8 +26,35 @@
#include "bp-sym.h"
#include "bp-asm.h"
- .text
-ENTRY (BP_SYM (strcmp))
+#undef UPDATE_STRNCMP_COUNTER
+
+#ifndef LABEL
+#define LABEL(l) L(l)
+#endif
+
+#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 LABEL(strcmp_exitz); \
+ test %r9, %r9; \
+ je LABEL(strcmp_exitz); \
+ mov %r9, %r11
+
+#else
+# define UPDATE_STRNCMP_COUNTER
+# ifndef STRCMP
+# define STRCMP strcmp
+# endif
+#endif
+
+ .text
+ENTRY (BP_SYM (STRCMP))
+#ifdef NOT_IN_libc
+/* Simple version since we can't use SSE registers in ld.so. */
L(oop): movb (%rdi), %al
cmpb (%rsi), %al
jne L(neq)
@@ -41,5 +70,1914 @@ L(neq): movl $1, %eax
movl $-1, %ecx
cmovbl %ecx, %eax
ret
-END (BP_SYM (strcmp))
-libc_hidden_builtin_def (strcmp)
+END (BP_SYM (STRCMP))
+#else /* NOT_IN_libc */
+/*
+ * This implementation uses SSE to compare up to 16 bytes at a time.
+ */
+#ifdef USE_AS_STRNCMP
+ test %rdx, %rdx
+ je LABEL(strcmp_exitz)
+ cmp $1, %rdx
+ je LABEL(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 LABEL(crosscache) /* rsi: 16-byte load will cross cache line */
+ cmp $0x30, %eax
+ ja LABEL(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 LABEL(less16bytes) /* If not, find different value or null char */
+#ifdef USE_AS_STRNCMP
+ sub $16, %r11
+ jbe LABEL(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
+LABEL(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 LABEL(ashr_0) /* rsi and rdi relative offset same */
+ ja LABEL(bigger)
+ mov %edx, %r8d /* r8d is offset flag for exit tail */
+ xchg %ecx, %eax
+ xchg %rsi, %rdi
+LABEL(bigger):
+ lea 15(%rax), %r9
+ sub %rcx, %r9
+ lea LABEL(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
+LABEL(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 LABEL(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
+LABEL(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 LABEL(exit) /* mismatch or null char seen */
+
+#ifdef USE_AS_STRNCMP
+ sub $16, %r11
+ jbe LABEL(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 LABEL(exit)
+#ifdef USE_AS_STRNCMP
+ sub $16, %r11
+ jbe LABEL(strcmp_exitz)
+#endif
+ add $16, %rcx
+ jmp LABEL(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
+LABEL(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 LABEL(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
+LABEL(loop_ashr_1):
+ add $16, %r10
+ jg LABEL(nibble_ashr_1) /* cross page boundary */
+
+LABEL(gobble_ashr_1):
+ movdqa (%rsi, %rcx), %xmm1
+ movdqa (%rdi, %rcx), %xmm2
+ movdqa %xmm2, %xmm4 /* store for next cycle */
+
+ psrldq $1, %xmm3
+ pslldq $15, %xmm2
+ por %xmm3, %xmm2 /* merge into one 16byte value */
+
+ pcmpeqb %xmm1, %xmm0
+ pcmpeqb %xmm2, %xmm1
+ psubb %xmm0, %xmm1
+ pmovmskb %xmm1, %edx
+ sub $0xffff, %edx
+ jnz LABEL(exit)
+
+#ifdef USE_AS_STRNCMP
+ sub $16, %r11
+ jbe LABEL(strcmp_exitz)
+#endif
+ add $16, %rcx
+ movdqa %xmm4, %xmm3
+
+ add $16, %r10
+ jg LABEL(nibble_ashr_1) /* cross page boundary */
+
+ movdqa (%rsi, %rcx), %xmm1
+ movdqa (%rdi, %rcx), %xmm2
+ movdqa %xmm2, %xmm4 /* store for next cycle */
+
+ psrldq $1, %xmm3
+ pslldq $15, %xmm2
+ por %xmm3, %xmm2 /* merge into one 16byte value */
+
+ pcmpeqb %xmm1, %xmm0
+ pcmpeqb %xmm2, %xmm1
+ psubb %xmm0, %xmm1
+ pmovmskb %xmm1, %edx
+ sub $0xffff, %edx
+ jnz LABEL(exit)
+
+#ifdef USE_AS_STRNCMP
+ sub $16, %r11
+ jbe LABEL(strcmp_exitz)
+#endif
+ add $16, %rcx
+ movdqa %xmm4, %xmm3
+ jmp LABEL(loop_ashr_1)
+
+ /*
+ * Nibble avoids loads across page boundary. This is to avoid a potential
+ * access into unmapped memory.
+ */
+ .p2align 4
+LABEL(nibble_ashr_1):
+ pcmpeqb %xmm3, %xmm0 /* check nibble for null char*/
+ pmovmskb %xmm0, %edx
+ test $0xfffe, %edx
+ jnz LABEL(ashr_1_exittail) /* find null char*/
+
+#ifdef USE_AS_STRNCMP
+ cmp $14, %r11
+ jbe LABEL(ashr_1_exittail)
+#endif
+
+ pxor %xmm0, %xmm0
+ sub $0x1000, %r10 /* substract 4K from %r10 */
+ jmp LABEL(gobble_ashr_1)
+
+ /*
+ * Once find null char, determine if there is a string mismatch
+ * before the null char.
+ */
+ .p2align 4
+LABEL(ashr_1_exittail):
+ movdqa (%rsi, %rcx), %xmm1
+ psrldq $1, %xmm0
+ psrldq $1, %xmm3
+ jmp LABEL(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
+LABEL(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 LABEL(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
+LABEL(loop_ashr_2):
+ add $16, %r10
+ jg LABEL(nibble_ashr_2)
+
+LABEL(gobble_ashr_2):
+ movdqa (%rsi, %rcx), %xmm1
+ movdqa (%rdi, %rcx), %xmm2
+ movdqa %xmm2, %xmm4
+
+ psrldq $2, %xmm3
+ pslldq $14, %xmm2
+ por %xmm3, %xmm2
+
+ pcmpeqb %xmm1, %xmm0
+ pcmpeqb %xmm2, %xmm1
+ psubb %xmm0, %xmm1
+ pmovmskb %xmm1, %edx
+ sub $0xffff, %edx
+ jnz LABEL(exit)
+
+#ifdef USE_AS_STRNCMP
+ sub $16, %r11
+ jbe LABEL(strcmp_exitz)
+#endif
+
+ add $16, %rcx
+ movdqa %xmm4, %xmm3
+
+ add $16, %r10
+ jg LABEL(nibble_ashr_2) /* cross page boundary */
+
+ movdqa (%rsi, %rcx), %xmm1
+ movdqa (%rdi, %rcx), %xmm2
+ movdqa %xmm2, %xmm4
+
+ psrldq $2, %xmm3
+ pslldq $14, %xmm2
+ por %xmm3, %xmm2
+
+ pcmpeqb %xmm1, %xmm0
+ pcmpeqb %xmm2, %xmm1
+ psubb %xmm0, %xmm1
+ pmovmskb %xmm1, %edx
+ sub $0xffff, %edx
+ jnz LABEL(exit)
+
+#ifdef USE_AS_STRNCMP
+ sub $16, %r11
+ jbe LABEL(strcmp_exitz)
+#endif
+
+ add $16, %rcx
+ movdqa %xmm4, %xmm3
+ jmp LABEL(loop_ashr_2)
+
+ .p2align 4
+LABEL(nibble_ashr_2):
+ pcmpeqb %xmm3, %xmm0 /* check nibble for null char */
+ pmovmskb %xmm0, %edx
+ test $0xfffc, %edx
+ jnz LABEL(ashr_2_exittail)
+
+#ifdef USE_AS_STRNCMP
+ cmp $13, %r11
+ jbe LABEL(ashr_2_exittail)
+#endif
+
+ pxor %xmm0, %xmm0
+ sub $0x1000, %r10
+ jmp LABEL(gobble_ashr_2)
+
+ .p2align 4
+LABEL(ashr_2_exittail):
+ movdqa (%rsi, %rcx), %xmm1
+ psrldq $2, %xmm0
+ psrldq $2, %xmm3
+ jmp LABEL(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
+LABEL(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 LABEL(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
+LABEL(loop_ashr_3):
+ add $16, %r10
+ jg LABEL(nibble_ashr_3)
+
+LABEL(gobble_ashr_3):
+ movdqa (%rsi, %rcx), %xmm1
+ movdqa (%rdi, %rcx), %xmm2
+ movdqa %xmm2, %xmm4
+
+ psrldq $3, %xmm3
+ pslldq $13, %xmm2
+ por %xmm3, %xmm2
+
+ pcmpeqb %xmm1, %xmm0
+ pcmpeqb %xmm2, %xmm1
+ psubb %xmm0, %xmm1
+ pmovmskb %xmm1, %edx
+ sub $0xffff, %edx
+ jnz LABEL(exit)
+
+#ifdef USE_AS_STRNCMP
+ sub $16, %r11
+ jbe LABEL(strcmp_exitz)
+#endif
+
+ add $16, %rcx
+ movdqa %xmm4, %xmm3
+
+ add $16, %r10
+ jg LABEL(nibble_ashr_3) /* cross page boundary */
+
+ movdqa (%rsi, %rcx), %xmm1
+ movdqa (%rdi, %rcx), %xmm2
+ movdqa %xmm2, %xmm4
+
+ psrldq $3, %xmm3
+ pslldq $13, %xmm2
+ por %xmm3, %xmm2
+
+ pcmpeqb %xmm1, %xmm0
+ pcmpeqb %xmm2, %xmm1
+ psubb %xmm0, %xmm1
+ pmovmskb %xmm1, %edx
+ sub $0xffff, %edx
+ jnz LABEL(exit)
+
+#ifdef USE_AS_STRNCMP
+ sub $16, %r11
+ jbe LABEL(strcmp_exitz)
+#endif
+
+ add $16, %rcx
+ movdqa %xmm4, %xmm3
+ jmp LABEL(loop_ashr_3)
+
+ .p2align 4
+LABEL(nibble_ashr_3):
+ pcmpeqb %xmm3, %xmm0 /* check nibble for null char */
+ pmovmskb %xmm0, %edx
+ test $0xfff8, %edx
+ jnz LABEL(ashr_3_exittail)
+
+#ifdef USE_AS_STRNCMP
+ cmp $12, %r11
+ jbe LABEL(ashr_3_exittail)
+#endif
+
+ pxor %xmm0, %xmm0
+ sub $0x1000, %r10
+ jmp LABEL(gobble_ashr_3)
+
+ .p2align 4
+LABEL(ashr_3_exittail):
+ movdqa (%rsi, %rcx), %xmm1
+ psrldq $3, %xmm0
+ psrldq $3, %xmm3
+ jmp LABEL(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
+LABEL(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 LABEL(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
+LABEL(loop_ashr_4):
+ add $16, %r10
+ jg LABEL(nibble_ashr_4)
+
+LABEL(gobble_ashr_4):
+ movdqa (%rsi, %rcx), %xmm1
+ movdqa (%rdi, %rcx), %xmm2
+ movdqa %xmm2, %xmm4
+
+ psrldq $4, %xmm3
+ pslldq $12, %xmm2
+ por %xmm3, %xmm2
+
+ pcmpeqb %xmm1, %xmm0
+ pcmpeqb %xmm2, %xmm1
+ psubb %xmm0, %xmm1
+ pmovmskb %xmm1, %edx
+ sub $0xffff, %edx
+ jnz LABEL(exit)
+
+#ifdef USE_AS_STRNCMP
+ sub $16, %r11
+ jbe LABEL(strcmp_exitz)
+#endif
+
+ add $16, %rcx
+ movdqa %xmm4, %xmm3
+
+ add $16, %r10
+ jg LABEL(nibble_ashr_4) /* cross page boundary */
+
+ movdqa (%rsi, %rcx), %xmm1
+ movdqa (%rdi, %rcx), %xmm2
+ movdqa %xmm2, %xmm4
+
+ psrldq $4, %xmm3
+ pslldq $12, %xmm2
+ por %xmm3, %xmm2
+
+ pcmpeqb %xmm1, %xmm0
+ pcmpeqb %xmm2, %xmm1
+ psubb %xmm0, %xmm1
+ pmovmskb %xmm1, %edx
+ sub $0xffff, %edx
+ jnz LABEL(exit)
+
+#ifdef USE_AS_STRNCMP
+ sub $16, %r11
+ jbe LABEL(strcmp_exitz)
+#endif
+
+ add $16, %rcx
+ movdqa %xmm4, %xmm3
+ jmp LABEL(loop_ashr_4)
+
+ .p2align 4
+LABEL(nibble_ashr_4):
+ pcmpeqb %xmm3, %xmm0 /* check nibble for null char */
+ pmovmskb %xmm0, %edx
+ test $0xfff0, %edx
+ jnz LABEL(ashr_4_exittail)
+
+#ifdef USE_AS_STRNCMP
+ cmp $11, %r11
+ jbe LABEL(ashr_4_exittail)
+#endif
+
+ pxor %xmm0, %xmm0
+ sub $0x1000, %r10
+ jmp LABEL(gobble_ashr_4)
+
+ .p2align 4
+LABEL(ashr_4_exittail):
+ movdqa (%rsi, %rcx), %xmm1
+ psrldq $4, %xmm0
+ psrldq $4, %xmm3
+ jmp LABEL(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
+LABEL(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 LABEL(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
+LABEL(loop_ashr_5):
+ add $16, %r10
+ jg LABEL(nibble_ashr_5)
+
+LABEL(gobble_ashr_5):
+ movdqa (%rsi, %rcx), %xmm1
+ movdqa (%rdi, %rcx), %xmm2
+ movdqa %xmm2, %xmm4
+
+ psrldq $5, %xmm3
+ pslldq $11, %xmm2
+ por %xmm3, %xmm2
+
+ pcmpeqb %xmm1, %xmm0
+ pcmpeqb %xmm2, %xmm1
+ psubb %xmm0, %xmm1
+ pmovmskb %xmm1, %edx
+ sub $0xffff, %edx
+ jnz LABEL(exit)
+
+#ifdef USE_AS_STRNCMP
+ sub $16, %r11
+ jbe LABEL(strcmp_exitz)
+#endif
+
+ add $16, %rcx
+ movdqa %xmm4, %xmm3
+
+ add $16, %r10
+ jg LABEL(nibble_ashr_5) /* cross page boundary */
+
+ movdqa (%rsi, %rcx), %xmm1
+ movdqa (%rdi, %rcx), %xmm2
+ movdqa %xmm2, %xmm4
+
+ psrldq $5, %xmm3
+ pslldq $11, %xmm2
+ por %xmm3, %xmm2
+
+ pcmpeqb %xmm1, %xmm0
+ pcmpeqb %xmm2, %xmm1
+ psubb %xmm0, %xmm1
+ pmovmskb %xmm1, %edx
+ sub $0xffff, %edx
+ jnz LABEL(exit)
+
+#ifdef USE_AS_STRNCMP
+ sub $16, %r11
+ jbe LABEL(strcmp_exitz)
+#endif
+
+ add $16, %rcx
+ movdqa %xmm4, %xmm3
+ jmp LABEL(loop_ashr_5)
+
+ .p2align 4
+LABEL(nibble_ashr_5):
+ pcmpeqb %xmm3, %xmm0 /* check nibble for null char */
+ pmovmskb %xmm0, %edx
+ test $0xffe0, %edx
+ jnz LABEL(ashr_5_exittail)
+
+#ifdef USE_AS_STRNCMP
+ cmp $10, %r11
+ jbe LABEL(ashr_5_exittail)
+#endif
+
+ pxor %xmm0, %xmm0
+ sub $0x1000, %r10
+ jmp LABEL(gobble_ashr_5)
+
+ .p2align 4
+LABEL(ashr_5_exittail):
+ movdqa (%rsi, %rcx), %xmm1
+ psrldq $5, %xmm0
+ psrldq $5, %xmm3
+ jmp LABEL(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
+LABEL(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 LABEL(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
+LABEL(loop_ashr_6):
+ add $16, %r10
+ jg LABEL(nibble_ashr_6)
+
+LABEL(gobble_ashr_6):
+ movdqa (%rsi, %rcx), %xmm1
+ movdqa (%rdi, %rcx), %xmm2
+ movdqa %xmm2, %xmm4
+
+ psrldq $6, %xmm3
+ pslldq $10, %xmm2
+ por %xmm3, %xmm2
+
+ pcmpeqb %xmm1, %xmm0
+ pcmpeqb %xmm2, %xmm1
+ psubb %xmm0, %xmm1
+ pmovmskb %xmm1, %edx
+ sub $0xffff, %edx
+ jnz LABEL(exit)
+
+#ifdef USE_AS_STRNCMP
+ sub $16, %r11
+ jbe LABEL(strcmp_exitz)
+#endif
+
+ add $16, %rcx
+ movdqa %xmm4, %xmm3
+
+ add $16, %r10
+ jg LABEL(nibble_ashr_6) /* cross page boundary */
+
+ movdqa (%rsi, %rcx), %xmm1
+ movdqa (%rdi, %rcx), %xmm2
+ movdqa %xmm2, %xmm4
+
+ psrldq $6, %xmm3
+ pslldq $10, %xmm2
+ por %xmm3, %xmm2
+
+ pcmpeqb %xmm1, %xmm0
+ pcmpeqb %xmm2, %xmm1
+ psubb %xmm0, %xmm1
+ pmovmskb %xmm1, %edx
+ sub $0xffff, %edx
+ jnz LABEL(exit)
+
+#ifdef USE_AS_STRNCMP
+ sub $16, %r11
+ jbe LABEL(strcmp_exitz)
+#endif
+
+ add $16, %rcx
+ movdqa %xmm4, %xmm3
+ jmp LABEL(loop_ashr_6)
+
+ .p2align 4
+LABEL(nibble_ashr_6):
+ pcmpeqb %xmm3, %xmm0 /* check nibble for null char */
+ pmovmskb %xmm0, %edx
+ test $0xffc0, %edx
+ jnz LABEL(ashr_6_exittail)
+
+#ifdef USE_AS_STRNCMP
+ cmp $9, %r11
+ jbe LABEL(ashr_6_exittail)
+#endif
+
+ pxor %xmm0, %xmm0
+ sub $0x1000, %r10
+ jmp LABEL(gobble_ashr_6)
+
+ .p2align 4
+LABEL(ashr_6_exittail):
+ movdqa (%rsi, %rcx), %xmm1
+ psrldq $6, %xmm0
+ psrldq $6, %xmm3
+ jmp LABEL(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
+LABEL(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 LABEL(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
+LABEL(loop_ashr_7):
+ add $16, %r10
+ jg LABEL(nibble_ashr_7)
+
+LABEL(gobble_ashr_7):
+ movdqa (%rsi, %rcx), %xmm1
+ movdqa (%rdi, %rcx), %xmm2
+ movdqa %xmm2, %xmm4
+
+ psrldq $7, %xmm3
+ pslldq $9, %xmm2
+ por %xmm3, %xmm2
+
+ pcmpeqb %xmm1, %xmm0
+ pcmpeqb %xmm2, %xmm1
+ psubb %xmm0, %xmm1
+ pmovmskb %xmm1, %edx
+ sub $0xffff, %edx
+ jnz LABEL(exit)
+
+#ifdef USE_AS_STRNCMP
+ sub $16, %r11
+ jbe LABEL(strcmp_exitz)
+#endif
+
+ add $16, %rcx
+ movdqa %xmm4, %xmm3
+
+ add $16, %r10
+ jg LABEL(nibble_ashr_7) /* cross page boundary */
+
+ movdqa (%rsi, %rcx), %xmm1
+ movdqa (%rdi, %rcx), %xmm2
+ movdqa %xmm2, %xmm4
+
+ psrldq $7, %xmm3
+ pslldq $9, %xmm2
+ por %xmm3, %xmm2
+
+ pcmpeqb %xmm1, %xmm0
+ pcmpeqb %xmm2, %xmm1
+ psubb %xmm0, %xmm1
+ pmovmskb %xmm1, %edx
+ sub $0xffff, %edx
+ jnz LABEL(exit)
+
+#ifdef USE_AS_STRNCMP
+ sub $16, %r11
+ jbe LABEL(strcmp_exitz)
+#endif
+
+ add $16, %rcx
+ movdqa %xmm4, %xmm3
+ jmp LABEL(loop_ashr_7)
+
+ .p2align 4
+LABEL(nibble_ashr_7):
+ pcmpeqb %xmm3, %xmm0 /* check nibble for null char */
+ pmovmskb %xmm0, %edx
+ test $0xff80, %edx
+ jnz LABEL(ashr_7_exittail)
+
+#ifdef USE_AS_STRNCMP
+ cmp $8, %r11
+ jbe LABEL(ashr_7_exittail)
+#endif
+
+ pxor %xmm0, %xmm0
+ sub $0x1000, %r10
+ jmp LABEL(gobble_ashr_7)
+
+ .p2align 4
+LABEL(ashr_7_exittail):
+ movdqa (%rsi, %rcx), %xmm1
+ psrldq $7, %xmm0
+ psrldq $7, %xmm3
+ jmp LABEL(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
+LABEL(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 LABEL(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
+LABEL(loop_ashr_8):
+ add $16, %r10
+ jg LABEL(nibble_ashr_8)
+
+LABEL(gobble_ashr_8):
+ movdqa (%rsi, %rcx), %xmm1
+ movdqa (%rdi, %rcx), %xmm2
+ movdqa %xmm2, %xmm4
+
+ psrldq $8, %xmm3
+ pslldq $8, %xmm2
+ por %xmm3, %xmm2
+
+ pcmpeqb %xmm1, %xmm0
+ pcmpeqb %xmm2, %xmm1
+ psubb %xmm0, %xmm1
+ pmovmskb %xmm1, %edx
+ sub $0xffff, %edx
+ jnz LABEL(exit)
+
+#ifdef USE_AS_STRNCMP
+ sub $16, %r11
+ jbe LABEL(strcmp_exitz)
+#endif
+
+ add $16, %rcx
+ movdqa %xmm4, %xmm3
+
+ add $16, %r10
+ jg LABEL(nibble_ashr_8) /* cross page boundary */
+
+ movdqa (%rsi, %rcx), %xmm1
+ movdqa (%rdi, %rcx), %xmm2
+ movdqa %xmm2, %xmm4
+
+ psrldq $8, %xmm3
+ pslldq $8, %xmm2
+ por %xmm3, %xmm2
+
+ pcmpeqb %xmm1, %xmm0
+ pcmpeqb %xmm2, %xmm1
+ psubb %xmm0, %xmm1
+ pmovmskb %xmm1, %edx
+ sub $0xffff, %edx
+ jnz LABEL(exit)
+
+#ifdef USE_AS_STRNCMP
+ sub $16, %r11
+ jbe LABEL(strcmp_exitz)
+#endif
+
+ add $16, %rcx
+ movdqa %xmm4, %xmm3
+ jmp LABEL(loop_ashr_8)
+
+ .p2align 4
+LABEL(nibble_ashr_8):
+ pcmpeqb %xmm3, %xmm0 /* check nibble for null char */
+ pmovmskb %xmm0, %edx
+ test $0xff00, %edx
+ jnz LABEL(ashr_8_exittail)
+
+#ifdef USE_AS_STRNCMP
+ cmp $7, %r11
+ jbe LABEL(ashr_8_exittail)
+#endif
+
+ pxor %xmm0, %xmm0
+ sub $0x1000, %r10
+ jmp LABEL(gobble_ashr_8)
+
+ .p2align 4
+LABEL(ashr_8_exittail):
+ movdqa (%rsi, %rcx), %xmm1
+ psrldq $8, %xmm0
+ psrldq $8, %xmm3
+ jmp LABEL(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
+LABEL(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 LABEL(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
+LABEL(loop_ashr_9):
+ add $16, %r10
+ jg LABEL(nibble_ashr_9)
+
+LABEL(gobble_ashr_9):
+ movdqa (%rsi, %rcx), %xmm1
+ movdqa (%rdi, %rcx), %xmm2
+ movdqa %xmm2, %xmm4
+
+ psrldq $9, %xmm3
+ pslldq $7, %xmm2
+ por %xmm3, %xmm2
+
+ pcmpeqb %xmm1, %xmm0
+ pcmpeqb %xmm2, %xmm1
+ psubb %xmm0, %xmm1
+ pmovmskb %xmm1, %edx
+ sub $0xffff, %edx
+ jnz LABEL(exit)
+
+#ifdef USE_AS_STRNCMP
+ sub $16, %r11
+ jbe LABEL(strcmp_exitz)
+#endif
+
+ add $16, %rcx
+ movdqa %xmm4, %xmm3
+
+ add $16, %r10
+ jg LABEL(nibble_ashr_9) /* cross page boundary */
+
+ movdqa (%rsi, %rcx), %xmm1
+ movdqa (%rdi, %rcx), %xmm2
+ movdqa %xmm2, %xmm4
+
+ psrldq $9, %xmm3
+ pslldq $7, %xmm2
+ por %xmm3, %xmm2
+
+ pcmpeqb %xmm1, %xmm0
+ pcmpeqb %xmm2, %xmm1
+ psubb %xmm0, %xmm1
+ pmovmskb %xmm1, %edx
+ sub $0xffff, %edx
+ jnz LABEL(exit)
+
+#ifdef USE_AS_STRNCMP
+ sub $16, %r11
+ jbe LABEL(strcmp_exitz)
+#endif
+
+ add $16, %rcx
+ movdqa %xmm4, %xmm3 /* store for next cycle */
+ jmp LABEL(loop_ashr_9)
+
+ .p2align 4
+LABEL(nibble_ashr_9):
+ pcmpeqb %xmm3, %xmm0 /* check nibble for null char */
+ pmovmskb %xmm0, %edx
+ test $0xfe00, %edx
+ jnz LABEL(ashr_9_exittail)
+
+#ifdef USE_AS_STRNCMP
+ cmp $6, %r11
+ jbe LABEL(ashr_9_exittail)
+#endif
+
+ pxor %xmm0, %xmm0
+ sub $0x1000, %r10
+ jmp LABEL(gobble_ashr_9)
+
+ .p2align 4
+LABEL(ashr_9_exittail):
+ movdqa (%rsi, %rcx), %xmm1
+ psrldq $9, %xmm0
+ psrldq $9, %xmm3
+ jmp LABEL(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
+LABEL(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 LABEL(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
+LABEL(loop_ashr_10):
+ add $16, %r10
+ jg LABEL(nibble_ashr_10)
+
+LABEL(gobble_ashr_10):
+ movdqa (%rsi, %rcx), %xmm1
+ movdqa (%rdi, %rcx), %xmm2
+ movdqa %xmm2, %xmm4
+
+ psrldq $10, %xmm3
+ pslldq $6, %xmm2
+ por %xmm3, %xmm2
+
+ pcmpeqb %xmm1, %xmm0
+ pcmpeqb %xmm2, %xmm1
+ psubb %xmm0, %xmm1
+ pmovmskb %xmm1, %edx
+ sub $0xffff, %edx
+ jnz LABEL(exit)
+
+#ifdef USE_AS_STRNCMP
+ sub $16, %r11
+ jbe LABEL(strcmp_exitz)
+#endif
+
+ add $16, %rcx
+ movdqa %xmm4, %xmm3
+
+ add $16, %r10
+ jg LABEL(nibble_ashr_10) /* cross page boundary */
+
+ movdqa (%rsi, %rcx), %xmm1
+ movdqa (%rdi, %rcx), %xmm2
+ movdqa %xmm2, %xmm4
+
+ psrldq $10, %xmm3
+ pslldq $6, %xmm2
+ por %xmm3, %xmm2
+
+ pcmpeqb %xmm1, %xmm0
+ pcmpeqb %xmm2, %xmm1
+ psubb %xmm0, %xmm1
+ pmovmskb %xmm1, %edx
+ sub $0xffff, %edx
+ jnz LABEL(exit)
+
+#ifdef USE_AS_STRNCMP
+ sub $16, %r11
+ jbe LABEL(strcmp_exitz)
+#endif
+
+ add $16, %rcx
+ movdqa %xmm4, %xmm3
+ jmp LABEL(loop_ashr_10)
+
+ .p2align 4
+LABEL(nibble_ashr_10):
+ pcmpeqb %xmm3, %xmm0 /* check nibble for null char */
+ pmovmskb %xmm0, %edx
+ test $0xfc00, %edx
+ jnz LABEL(ashr_10_exittail)
+
+#ifdef USE_AS_STRNCMP
+ cmp $5, %r11
+ jbe LABEL(ashr_10_exittail)
+#endif
+
+ pxor %xmm0, %xmm0
+ sub $0x1000, %r10
+ jmp LABEL(gobble_ashr_10)
+
+ .p2align 4
+LABEL(ashr_10_exittail):
+ movdqa (%rsi, %rcx), %xmm1
+ psrldq $10, %xmm0
+ psrldq $10, %xmm3
+ jmp LABEL(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
+LABEL(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 LABEL(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
+LABEL(loop_ashr_11):
+ add $16, %r10
+ jg LABEL(nibble_ashr_11)
+
+LABEL(gobble_ashr_11):
+ movdqa (%rsi, %rcx), %xmm1
+ movdqa (%rdi, %rcx), %xmm2
+ movdqa %xmm2, %xmm4
+
+ psrldq $11, %xmm3
+ pslldq $5, %xmm2
+ por %xmm3, %xmm2
+
+ pcmpeqb %xmm1, %xmm0
+ pcmpeqb %xmm2, %xmm1
+ psubb %xmm0, %xmm1
+ pmovmskb %xmm1, %edx
+ sub $0xffff, %edx
+ jnz LABEL(exit)
+
+#ifdef USE_AS_STRNCMP
+ sub $16, %r11
+ jbe LABEL(strcmp_exitz)
+#endif
+
+ add $16, %rcx
+ movdqa %xmm4, %xmm3
+
+ add $16, %r10
+ jg LABEL(nibble_ashr_11) /* cross page boundary */
+
+ movdqa (%rsi, %rcx), %xmm1
+ movdqa (%rdi, %rcx), %xmm2
+ movdqa %xmm2, %xmm4
+
+ psrldq $11, %xmm3
+ pslldq $5, %xmm2
+ por %xmm3, %xmm2
+
+ pcmpeqb %xmm1, %xmm0
+ pcmpeqb %xmm2, %xmm1
+ psubb %xmm0, %xmm1
+ pmovmskb %xmm1, %edx
+ sub $0xffff, %edx
+ jnz LABEL(exit)
+
+#ifdef USE_AS_STRNCMP
+ sub $16, %r11
+ jbe LABEL(strcmp_exitz)
+#endif
+
+ add $16, %rcx
+ movdqa %xmm4, %xmm3
+ jmp LABEL(loop_ashr_11)
+
+ .p2align 4
+LABEL(nibble_ashr_11):
+ pcmpeqb %xmm3, %xmm0 /* check nibble for null char */
+ pmovmskb %xmm0, %edx
+ test $0xf800, %edx
+ jnz LABEL(ashr_11_exittail)
+
+#ifdef USE_AS_STRNCMP
+ cmp $4, %r11
+ jbe LABEL(ashr_11_exittail)
+#endif
+
+ pxor %xmm0, %xmm0
+ sub $0x1000, %r10
+ jmp LABEL(gobble_ashr_11)
+
+ .p2align 4
+LABEL(ashr_11_exittail):
+ movdqa (%rsi, %rcx), %xmm1
+ psrldq $11, %xmm0
+ psrldq $11, %xmm3
+ jmp LABEL(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
+LABEL(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 LABEL(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
+LABEL(loop_ashr_12):
+ add $16, %r10
+ jg LABEL(nibble_ashr_12)
+
+LABEL(gobble_ashr_12):
+ movdqa (%rsi, %rcx), %xmm1
+ movdqa (%rdi, %rcx), %xmm2
+ movdqa %xmm2, %xmm4
+
+ psrldq $12, %xmm3
+ pslldq $4, %xmm2
+ por %xmm3, %xmm2
+
+ pcmpeqb %xmm1, %xmm0
+ pcmpeqb %xmm2, %xmm1
+ psubb %xmm0, %xmm1
+ pmovmskb %xmm1, %edx
+ sub $0xffff, %edx
+ jnz LABEL(exit)
+
+#ifdef USE_AS_STRNCMP
+ sub $16, %r11
+ jbe LABEL(strcmp_exitz)
+#endif
+
+ add $16, %rcx
+ movdqa %xmm4, %xmm3
+
+ add $16, %r10
+ jg LABEL(nibble_ashr_12) /* cross page boundary */
+
+ movdqa (%rsi, %rcx), %xmm1
+ movdqa (%rdi, %rcx), %xmm2
+ movdqa %xmm2, %xmm4
+
+ psrldq $12, %xmm3
+ pslldq $4, %xmm2
+ por %xmm3, %xmm2
+
+ pcmpeqb %xmm1, %xmm0
+ pcmpeqb %xmm2, %xmm1
+ psubb %xmm0, %xmm1
+ pmovmskb %xmm1, %edx
+ sub $0xffff, %edx
+ jnz LABEL(exit)
+
+#ifdef USE_AS_STRNCMP
+ sub $16, %r11
+ jbe LABEL(strcmp_exitz)
+#endif
+
+ add $16, %rcx
+ movdqa %xmm4, %xmm3
+ jmp LABEL(loop_ashr_12)
+
+ .p2align 4
+LABEL(nibble_ashr_12):
+ pcmpeqb %xmm3, %xmm0 /* check nibble for null char */
+ pmovmskb %xmm0, %edx
+ test $0xf000, %edx
+ jnz LABEL(ashr_12_exittail)
+
+#ifdef USE_AS_STRNCMP
+ cmp $3, %r11
+ jbe LABEL(ashr_12_exittail)
+#endif
+
+ pxor %xmm0, %xmm0
+ sub $0x1000, %r10
+ jmp LABEL(gobble_ashr_12)
+
+ .p2align 4
+LABEL(ashr_12_exittail):
+ movdqa (%rsi, %rcx), %xmm1
+ psrldq $12, %xmm0
+ psrldq $12, %xmm3
+ jmp LABEL(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
+LABEL(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 LABEL(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
+LABEL(loop_ashr_13):
+ add $16, %r10
+ jg LABEL(nibble_ashr_13)
+
+LABEL(gobble_ashr_13):
+ movdqa (%rsi, %rcx), %xmm1
+ movdqa (%rdi, %rcx), %xmm2
+ movdqa %xmm2, %xmm4
+
+ psrldq $13, %xmm3
+ pslldq $3, %xmm2
+ por %xmm3, %xmm2
+
+ pcmpeqb %xmm1, %xmm0
+ pcmpeqb %xmm2, %xmm1
+ psubb %xmm0, %xmm1
+ pmovmskb %xmm1, %edx
+ sub $0xffff, %edx
+ jnz LABEL(exit)
+
+#ifdef USE_AS_STRNCMP
+ sub $16, %r11
+ jbe LABEL(strcmp_exitz)
+#endif
+
+ add $16, %rcx
+ movdqa %xmm4, %xmm3
+
+ add $16, %r10
+ jg LABEL(nibble_ashr_13) /* cross page boundary */
+
+ movdqa (%rsi, %rcx), %xmm1
+ movdqa (%rdi, %rcx), %xmm2
+ movdqa %xmm2, %xmm4
+
+ psrldq $13, %xmm3
+ pslldq $3, %xmm2
+ por %xmm3, %xmm2
+
+ pcmpeqb %xmm1, %xmm0
+ pcmpeqb %xmm2, %xmm1
+ psubb %xmm0, %xmm1
+ pmovmskb %xmm1, %edx
+ sub $0xffff, %edx
+ jnz LABEL(exit)
+
+#ifdef USE_AS_STRNCMP
+ sub $16, %r11
+ jbe LABEL(strcmp_exitz)
+#endif
+
+ add $16, %rcx
+ movdqa %xmm4, %xmm3
+ jmp LABEL(loop_ashr_13)
+
+ .p2align 4
+LABEL(nibble_ashr_13):
+ pcmpeqb %xmm3, %xmm0 /* check nibble for null char */
+ pmovmskb %xmm0, %edx
+ test $0xe000, %edx
+ jnz LABEL(ashr_13_exittail)
+
+#ifdef USE_AS_STRNCMP
+ cmp $2, %r11
+ jbe LABEL(ashr_13_exittail)
+#endif
+
+ pxor %xmm0, %xmm0
+ sub $0x1000, %r10
+ jmp LABEL(gobble_ashr_13)
+
+ .p2align 4
+LABEL(ashr_13_exittail):
+ movdqa (%rsi, %rcx), %xmm1
+ psrldq $13, %xmm0
+ psrldq $13, %xmm3
+ jmp LABEL(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
+LABEL(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 LABEL(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
+LABEL(loop_ashr_14):
+ add $16, %r10
+ jg LABEL(nibble_ashr_14)
+
+LABEL(gobble_ashr_14):
+ movdqa (%rsi, %rcx), %xmm1
+ movdqa (%rdi, %rcx), %xmm2
+ movdqa %xmm2, %xmm4
+
+ psrldq $14, %xmm3
+ pslldq $2, %xmm2
+ por %xmm3, %xmm2
+
+ pcmpeqb %xmm1, %xmm0
+ pcmpeqb %xmm2, %xmm1
+ psubb %xmm0, %xmm1
+ pmovmskb %xmm1, %edx
+ sub $0xffff, %edx
+ jnz LABEL(exit)
+
+#ifdef USE_AS_STRNCMP
+ sub $16, %r11
+ jbe LABEL(strcmp_exitz)
+#endif
+
+ add $16, %rcx
+ movdqa %xmm4, %xmm3
+
+ add $16, %r10
+ jg LABEL(nibble_ashr_14) /* cross page boundary */
+
+ movdqa (%rsi, %rcx), %xmm1
+ movdqa (%rdi, %rcx), %xmm2
+ movdqa %xmm2, %xmm4
+
+ psrldq $14, %xmm3
+ pslldq $2, %xmm2
+ por %xmm3, %xmm2
+
+ pcmpeqb %xmm1, %xmm0
+ pcmpeqb %xmm2, %xmm1
+ psubb %xmm0, %xmm1
+ pmovmskb %xmm1, %edx
+ sub $0xffff, %edx
+ jnz LABEL(exit)
+
+#ifdef USE_AS_STRNCMP
+ sub $16, %r11
+ jbe LABEL(strcmp_exitz)
+#endif
+
+ add $16, %rcx
+ movdqa %xmm4, %xmm3
+ jmp LABEL(loop_ashr_14)
+
+ .p2align 4
+LABEL(nibble_ashr_14):
+ pcmpeqb %xmm3, %xmm0 /* check nibble for null char */
+ pmovmskb %xmm0, %edx
+ test $0xc000, %edx
+ jnz LABEL(ashr_14_exittail)
+
+#ifdef USE_AS_STRNCMP
+ cmp $1, %r11
+ jbe LABEL(ashr_14_exittail)
+#endif
+
+ pxor %xmm0, %xmm0
+ sub $0x1000, %r10
+ jmp LABEL(gobble_ashr_14)
+
+ .p2align 4
+LABEL(ashr_14_exittail):
+ movdqa (%rsi, %rcx), %xmm1
+ psrldq $14, %xmm0
+ psrldq $14, %xmm3
+ jmp LABEL(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
+LABEL(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 LABEL(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
+LABEL(loop_ashr_15):
+ add $16, %r10
+ jg LABEL(nibble_ashr_15)
+
+LABEL(gobble_ashr_15):
+ movdqa (%rsi, %rcx), %xmm1
+ movdqa (%rdi, %rcx), %xmm2
+ movdqa %xmm2, %xmm4
+
+ psrldq $15, %xmm3
+ pslldq $1, %xmm2
+ por %xmm3, %xmm2
+
+ pcmpeqb %xmm1, %xmm0
+ pcmpeqb %xmm2, %xmm1
+ psubb %xmm0, %xmm1
+ pmovmskb %xmm1, %edx
+ sub $0xffff, %edx
+ jnz LABEL(exit)
+
+#ifdef USE_AS_STRNCMP
+ sub $16, %r11
+ jbe LABEL(strcmp_exitz)
+#endif
+
+ add $16, %rcx
+ movdqa %xmm4, %xmm3
+
+ add $16, %r10
+ jg LABEL(nibble_ashr_15) /* cross page boundary */
+
+ movdqa (%rsi, %rcx), %xmm1
+ movdqa (%rdi, %rcx), %xmm2
+ movdqa %xmm2, %xmm4
+
+ psrldq $15, %xmm3
+ pslldq $1, %xmm2
+ por %xmm3, %xmm2
+
+ pcmpeqb %xmm1, %xmm0
+ pcmpeqb %xmm2, %xmm1
+ psubb %xmm0, %xmm1
+ pmovmskb %xmm1, %edx
+ sub $0xffff, %edx
+ jnz LABEL(exit)
+
+#ifdef USE_AS_STRNCMP
+ sub $16, %r11
+ jbe LABEL(strcmp_exitz)
+#endif
+
+ add $16, %rcx
+ movdqa %xmm4, %xmm3
+ jmp LABEL(loop_ashr_15)
+
+ .p2align 4
+LABEL(nibble_ashr_15):
+ pcmpeqb %xmm3, %xmm0 /* check nibble for null char */
+ pmovmskb %xmm0, %edx
+ test $0x8000, %edx
+ jnz LABEL(ashr_15_exittail)
+
+#ifdef USE_AS_STRNCMP
+ test %r11, %r11
+ je LABEL(ashr_15_exittail)
+#endif
+
+ pxor %xmm0, %xmm0
+ sub $0x1000, %r10
+ jmp LABEL(gobble_ashr_15)
+
+ .p2align 4
+LABEL(ashr_15_exittail):
+ movdqa (%rsi, %rcx), %xmm1
+ psrldq $15, %xmm3
+ psrldq $15, %xmm0
+
+ .p2align 4
+LABEL(aftertail):
+ pcmpeqb %xmm3, %xmm1
+ psubb %xmm0, %xmm1
+ pmovmskb %xmm1, %edx
+ not %edx
+
+ .p2align 4
+LABEL(exit):
+ lea -16(%r9, %rcx), %rax /* locate the exact offset for rdi */
+LABEL(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 LABEL(ret)
+ xchg %rsi, %rdi /* recover original order according to flag(%r8d) */
+
+ .p2align 4
+LABEL(ret):
+LABEL(less16bytes):
+ bsf %rdx, %rdx /* find and store bit index in %rdx */
+
+#ifdef USE_AS_STRNCMP
+ sub %rdx, %r11
+ jbe LABEL(strcmp_exitz)
+#endif
+ movzbl (%rsi, %rdx), %ecx
+ movzbl (%rdi, %rdx), %eax
+
+ sub %ecx, %eax
+ ret
+
+LABEL(strcmp_exitz):
+ xor %eax, %eax
+ ret
+
+ .p2align 4
+LABEL(Byte0):
+ movzx (%rsi), %ecx
+ movzx (%rdi), %eax
+
+ sub %ecx, %eax
+ ret
+END (BP_SYM (STRCMP))
+
+ .section .rodata,"a",@progbits
+ .p2align 3
+LABEL(unaligned_table):
+ .int LABEL(ashr_1) - LABEL(unaligned_table)
+ .int LABEL(ashr_2) - LABEL(unaligned_table)
+ .int LABEL(ashr_3) - LABEL(unaligned_table)
+ .int LABEL(ashr_4) - LABEL(unaligned_table)
+ .int LABEL(ashr_5) - LABEL(unaligned_table)
+ .int LABEL(ashr_6) - LABEL(unaligned_table)
+ .int LABEL(ashr_7) - LABEL(unaligned_table)
+ .int LABEL(ashr_8) - LABEL(unaligned_table)
+ .int LABEL(ashr_9) - LABEL(unaligned_table)
+ .int LABEL(ashr_10) - LABEL(unaligned_table)
+ .int LABEL(ashr_11) - LABEL(unaligned_table)
+ .int LABEL(ashr_12) - LABEL(unaligned_table)
+ .int LABEL(ashr_13) - LABEL(unaligned_table)
+ .int LABEL(ashr_14) - LABEL(unaligned_table)
+ .int LABEL(ashr_15) - LABEL(unaligned_table)
+ .int LABEL(ashr_0) - LABEL(unaligned_table)
+#endif /* NOT_IN_libc */
+libc_hidden_builtin_def (STRCMP)