merge x86_64 optimized string support

16 files changed, 2875 insertions, 15 deletions

diff --git a/libc/string/Makefile b/libc/string/Makefile
index 600f3b81d..576f915af 100644
--- a/libc/string/Makefile
+++ b/libc/string/Makefile
@@ -1,20 +1,9 @@
 # Makefile for uClibc
 #
-# Copyright (C) 2000-2003 Erik Andersen <andersen@uclibc.org>
+# Copyright (C) 2000-2005 Erik Andersen <andersen@uclibc.org>
 #
-# This program is free software; you can redistribute it and/or modify it under
-# the terms of the GNU Library General Public License as published by the Free
-# Software Foundation; either version 2 of the License, or (at your option) any
-# later version.
-#
-# This program is distributed in the hope that it will be useful, but WITHOUT
-# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
-# FOR A PARTICULAR PURPOSE. See the GNU Library General Public License for more
-# details.
-#
-# You should have received a copy of the GNU Library General Public License
-# along with this program; if not, write to the Free Software Foundation, Inc.,
-# 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+# Licensed under the GNU Library General Public License version 2 or later.
+# See the COPYING.LIB file in the toplevel for more information.
 
 TOPDIR=../../
 include $(TOPDIR)Rules.mak
@@ -31,7 +20,7 @@ DIRS += $(TARGET_ARCH)
 endif
 endif
 
-ALL_SUBDIRS = generic arm frv i386 mips powerpc sh64 sparc
+ALL_SUBDIRS = generic arm frv i386 mips powerpc sh64 sparc x86_64
 
 MSRC= wstring.c
 MOBJ=  basename.o bcopy.o bzero.o dirname.o ffs.o memccpy.o memchr.o memcmp.o \
diff --git a/libc/string/x86_64/Makefile b/libc/string/x86_64/Makefile
new file mode 100644
index 000000000..2215a6025
--- /dev/null
+++ b/libc/string/x86_64/Makefile
@@ -0,0 +1,31 @@
+# Makefile for uClibc
+#
+# Copyright (C) 2000-2005 Erik Andersen <andersen@uclibc.org>
+#
+# Licensed under the GNU Library General Public License version 2 or later.
+# See the COPYING.LIB file in the toplevel for more information.
+
+TOPDIR=../../../
+include $(TOPDIR)Rules.mak
+
+CSRCS = $(wildcard *.c)
+COBJS = $(patsubst %.c,%.o,$(CSRCS))
+
+SSRCS = $(wildcard *.S)
+SOBJS = $(patsubst %.S,%.o,$(SSRCS))
+
+OBJS = $(COBJS) $(SOBJS)
+
+OBJ_LIST = ../../obj.string.$(TARGET_ARCH)
+
+all: $(OBJ_LIST)
+
+$(OBJ_LIST): $(OBJS)
+	echo $(patsubst %, string/$(TARGET_ARCH)/%, $(OBJS)) > $(OBJ_LIST)
+
+$(COBJS): %.o : %.c
+	$(CC) $(CFLAGS) -c $< -o $@
+	$(STRIPTOOL) -x -R .note -R .comment $*.o
+
+clean:
+	$(RM) *.[oa] *~ core
diff --git a/libc/string/x86_64/_glibc_inc.h b/libc/string/x86_64/_glibc_inc.h
new file mode 100644
index 000000000..f14b23c94
--- /dev/null
+++ b/libc/string/x86_64/_glibc_inc.h
@@ -0,0 +1,33 @@
+/*
+ * Setup some glibc defines so we can just drop in the
+ * asm files from glibc without any modification.
+ */
+
+#include <features.h>
+#include <bits/wordsize.h>
+
+#if __WORDSIZE == 32
+# define ENTRY_ALIGN 4
+#else
+# define ENTRY_ALIGN 2
+#endif
+
+#define ENTRY(sym) \
+	.global sym; \
+	.align  ENTRY_ALIGN; \
+	.type   sym,%function; \
+	sym:
+
+#define BP_SYM(sym) sym
+
+#define L(sym) LOC(sym)
+#define LOC(sym) \
+	.L ## sym
+
+#define END(sym) \
+	.size sym,.-sym;
+
+#undef weak_alias
+#define weak_alias(sym, alias) \
+	.weak alias; \
+    alias = sym;
diff --git a/libc/string/x86_64/bzero.S b/libc/string/x86_64/bzero.S
new file mode 100644
index 000000000..abd252e7b
--- /dev/null
+++ b/libc/string/x86_64/bzero.S
@@ -0,0 +1,3 @@
+#define memset __bzero
+#include "memset.S"
+weak_alias (__bzero, bzero)
diff --git a/libc/string/x86_64/memcpy.S b/libc/string/x86_64/memcpy.S
new file mode 100644
index 000000000..4fa38a640
--- /dev/null
+++ b/libc/string/x86_64/memcpy.S
@@ -0,0 +1,95 @@
+/* Highly optimized version for x86-64.
+   Copyright (C) 1997, 2000, 2002, 2003, 2004 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Based on i586 version contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include "_glibc_inc.h"
+
+/* BEWARE: `#ifdef memcpy' means that memcpy is redefined as `mempcpy',
+   and the return value is the byte after the last one copied in
+   the destination. */
+#define MEMPCPY_P (defined memcpy)
+
+        .text
+#if defined PIC && !defined NOT_IN_libc
+ENTRY (__memcpy_chk)
+	cmpq	%rdx, %rcx
+	jb	HIDDEN_JUMPTARGET (__chk_fail)
+END (__memcpy_chk)
+#endif
+ENTRY (BP_SYM (memcpy))
+	/* Cutoff for the big loop is a size of 32 bytes since otherwise
+	   the loop will never be entered.  */
+	cmpq	$32, %rdx
+	movq	%rdx, %rcx
+#if !MEMPCPY_P
+	movq	%rdi, %r10	/* Save value. */
+#endif
+
+	/* We need this in any case.  */
+	cld
+
+	jbe	1f
+
+	/* Align destination.  */
+	movq	%rdi, %rax
+	negq	%rax
+	andq	$7, %rax
+	subq	%rax, %rcx
+	xchgq	%rax, %rcx
+
+	rep; movsb
+
+	movq	%rax, %rcx
+	subq	$32, %rcx
+	js	2f
+
+	.p2align 4
+3:
+
+	/* Now correct the loop counter.  Please note that in the following
+	   code the flags are not changed anymore.  */
+	subq	$32, %rcx
+
+	movq	(%rsi), %rax
+	movq	8(%rsi), %rdx
+	movq	16(%rsi), %r8
+	movq	24(%rsi), %r9
+	movq	%rax, (%rdi)
+	movq	%rdx, 8(%rdi)
+	movq	%r8, 16(%rdi)
+	movq	%r9, 24(%rdi)
+
+	leaq	32(%rsi), %rsi
+	leaq	32(%rdi), %rdi
+
+	jns	3b
+
+	/* Correct extra loop counter modification.  */
+2:	addq	$32, %rcx
+1:	rep; movsb
+
+#if MEMPCPY_P
+	movq	%rdi, %rax		/* Set return value.  */
+#else
+	movq	%r10, %rax		/* Set return value.  */
+	
+#endif
+	ret
+
+END (BP_SYM (memcpy))
diff --git a/libc/string/x86_64/memset.S b/libc/string/x86_64/memset.S
new file mode 100644
index 000000000..d74ec8ccb
--- /dev/null
+++ b/libc/string/x86_64/memset.S
@@ -0,0 +1,138 @@
+/* memset/bzero -- set memory area to CH/0
+   Optimized version for x86-64.
+   Copyright (C) 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Andreas Jaeger <aj@suse.de>.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include "_glibc_inc.h"
+
+/* BEWARE: `#ifdef memset' means that memset is redefined as `bzero' */
+#define BZERO_P (defined memset)
+
+/* This is somehow experimental and could made dependend on the cache
+   size.  */
+#define LARGE $120000
+
+        .text
+#if !BZERO_P && defined PIC && !defined NOT_IN_libc
+ENTRY (__memset_chk)
+	cmpq	%rdx, %rcx
+	jb	HIDDEN_JUMPTARGET (__chk_fail)
+END (__memset_chk)
+#endif
+ENTRY (memset)
+#if BZERO_P
+	mov	%rsi,%rdx	/* Adjust parameter.  */
+	xorl	%esi,%esi	/* Fill with 0s.  */
+#endif
+	cmp	$0x7,%rdx	/* Check for small length.  */
+	mov	%rdi,%rcx	/* Save ptr as return value.  */
+	jbe	7f
+
+#if BZERO_P
+	mov	%rsi,%r8	/* Just copy 0.  */
+#else
+	/* Populate 8 bit data to full 64-bit.  */
+	movabs	$0x0101010101010101,%r8
+	movzbl	%sil,%eax
+	imul	%rax,%r8
+#endif
+	test	$0x7,%edi	/* Check for alignment.  */
+	je	2f
+
+	.p2align 4
+1:	/* Align ptr to 8 byte.  */
+	mov	%sil,(%rcx)
+	dec	%rdx
+	inc	%rcx
+	test	$0x7,%ecx
+	jne	1b
+
+2:	/* Check for really large regions.  */
+	mov	%rdx,%rax
+	shr	$0x6,%rax
+	je	4f
+	cmp	LARGE, %rdx
+	jae	11f
+
+	.p2align 4
+3:	/* Copy 64 bytes.  */
+	mov	%r8,(%rcx)
+	mov	%r8,0x8(%rcx)
+	mov	%r8,0x10(%rcx)
+	mov	%r8,0x18(%rcx)
+	mov	%r8,0x20(%rcx)
+	mov	%r8,0x28(%rcx)
+	mov	%r8,0x30(%rcx)
+	mov	%r8,0x38(%rcx)
+	add	$0x40,%rcx
+	dec	%rax
+	jne	3b
+
+4:	/* Copy final bytes.  */
+	and	$0x3f,%edx
+	mov	%rdx,%rax
+	shr	$0x3,%rax
+	je	6f
+
+5:	/* First in chunks of 8 bytes.  */
+	mov	%r8,(%rcx)
+	add	$0x8,%rcx
+	dec	%rax
+	jne	5b
+6:
+	and	$0x7,%edx
+7:
+	test	%rdx,%rdx
+	je	9f
+8:	/* And finally as bytes (up to 7).  */
+	mov	%sil,(%rcx)
+	inc	%rcx
+	dec	%rdx
+	jne	8b
+9:
+#if BZERO_P
+	nop
+#else
+	/* Load result (only if used as memset).  */
+	mov	%rdi,%rax	/* start address of destination is result */
+#endif
+	retq
+
+	.p2align 4
+11:	/* Copy 64 bytes without polluting the cache.  */
+	/* We could use	movntdq    %xmm0,(%rcx) here to further
+	   speed up for large cases but let's not use XMM registers.  */
+	movnti	%r8,(%rcx)
+	movnti  %r8,0x8(%rcx)
+	movnti  %r8,0x10(%rcx)
+	movnti  %r8,0x18(%rcx)
+	movnti  %r8,0x20(%rcx)
+	movnti  %r8,0x28(%rcx)
+	movnti  %r8,0x30(%rcx)
+	movnti  %r8,0x38(%rcx)
+	add	$0x40,%rcx
+	dec	%rax
+	jne	11b
+	jmp	4b
+
+END (memset)
+
+#if !BZERO_P && defined PIC && !defined NOT_IN_libc
+strong_alias (__memset_chk, __memset_zero_constant_len_parameter)
+#endif
diff --git a/libc/string/x86_64/stpcpy.S b/libc/string/x86_64/stpcpy.S
new file mode 100644
index 000000000..83294e1a8
--- /dev/null
+++ b/libc/string/x86_64/stpcpy.S
@@ -0,0 +1,6 @@
+#define USE_AS_STPCPY
+#define STRCPY __stpcpy
+
+#include "strcpy.S"
+
+weak_alias (__stpcpy, stpcpy)
diff --git a/libc/string/x86_64/strcat.S b/libc/string/x86_64/strcat.S
new file mode 100644
index 000000000..1106cb4ed
--- /dev/null
+++ b/libc/string/x86_64/strcat.S
@@ -0,0 +1,256 @@
+/* strcat(dest, src) -- Append SRC on the end of DEST.
+   Optimized for x86-64.
+   Copyright (C) 2002 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Andreas Jaeger <aj@suse.de>, 2002.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include "_glibc_inc.h"
+
+
+	.text
+ENTRY (BP_SYM (strcat))
+	movq %rdi, %rcx		/* Dest. register. */
+	andl $7, %ecx		/* mask alignment bits */
+	movq %rdi, %rax		/* Duplicate destination pointer.  */
+	movq $0xfefefefefefefeff,%r8
+
+	/* First step: Find end of destination.  */
+	jz 4f			/* aligned => start loop */
+
+	neg %ecx		/* We need to align to 8 bytes.  */
+	addl $8,%ecx
+	/* Search the first bytes directly.  */
+0:	cmpb $0x0,(%rax)	/* is byte NUL? */
+	je 2f			/* yes => start copy */
+	incq %rax		/* increment pointer */
+	decl %ecx
+	jnz 0b
+
+
+
+	/* Now the source is aligned.  Scan for NUL byte.  */
+	.p2align 4
+4:
+	/* First unroll.  */
+	movq (%rax), %rcx	/* get double word (= 8 bytes) in question */
+	addq $8,%rax		/* adjust pointer for next word */
+	movq %r8, %rdx		/* magic value */
+	addq %rcx, %rdx		/* add the magic value to the word.  We get
+				   carry bits reported for each byte which
+				   is *not* 0 */
+	jnc 3f			/* highest byte is NUL => return pointer */
+	xorq %rcx, %rdx		/* (word+magic)^word */
+	orq %r8, %rdx		/* set all non-carry bits */
+	incq %rdx		/* add 1: if one carry bit was *not* set
+				   the addition will not result in 0.  */
+	jnz 3f			/* found NUL => return pointer */
+
+	/* Second unroll.  */
+	movq (%rax), %rcx	/* get double word (= 8 bytes) in question */
+	addq $8,%rax		/* adjust pointer for next word */
+	movq %r8, %rdx		/* magic value */
+	addq %rcx, %rdx		/* add the magic value to the word.  We get
+				   carry bits reported for each byte which
+				   is *not* 0 */
+	jnc 3f			/* highest byte is NUL => return pointer */
+	xorq %rcx, %rdx		/* (word+magic)^word */
+	orq %r8, %rdx		/* set all non-carry bits */
+	incq %rdx		/* add 1: if one carry bit was *not* set
+				   the addition will not result in 0.  */
+	jnz 3f			/* found NUL => return pointer */
+
+	/* Third unroll.  */
+	movq (%rax), %rcx	/* get double word (= 8 bytes) in question */
+	addq $8,%rax		/* adjust pointer for next word */
+	movq %r8, %rdx		/* magic value */
+	addq %rcx, %rdx		/* add the magic value to the word.  We get
+				   carry bits reported for each byte which
+				   is *not* 0 */
+	jnc 3f			/* highest byte is NUL => return pointer */
+	xorq %rcx, %rdx		/* (word+magic)^word */
+	orq %r8, %rdx		/* set all non-carry bits */
+	incq %rdx		/* add 1: if one carry bit was *not* set
+				   the addition will not result in 0.  */
+	jnz 3f			/* found NUL => return pointer */
+
+	/* Fourth unroll.  */
+	movq (%rax), %rcx	/* get double word (= 8 bytes) in question */
+	addq $8,%rax		/* adjust pointer for next word */
+	movq %r8, %rdx		/* magic value */
+	addq %rcx, %rdx		/* add the magic value to the word.  We get
+				   carry bits reported for each byte which
+				   is *not* 0 */
+	jnc 3f			/* highest byte is NUL => return pointer */
+	xorq %rcx, %rdx		/* (word+magic)^word */
+	orq %r8, %rdx		/* set all non-carry bits */
+	incq %rdx		/* add 1: if one carry bit was *not* set
+				   the addition will not result in 0.  */
+	jz 4b			/* no NUL found => continue loop */
+
+	.p2align 4		/* Align, it's a jump target.  */
+3:	subq $8,%rax		/* correct pointer increment.  */
+
+	testb %cl, %cl		/* is first byte NUL? */
+	jz 2f			/* yes => return */
+	incq %rax		/* increment pointer */
+
+	testb %ch, %ch		/* is second byte NUL? */
+	jz 2f			/* yes => return */
+	incq %rax		/* increment pointer */
+
+	testl $0x00ff0000, %ecx /* is third byte NUL? */
+	jz 2f			/* yes => return pointer */
+	incq %rax		/* increment pointer */
+
+	testl $0xff000000, %ecx /* is fourth byte NUL? */
+	jz 2f			/* yes => return pointer */
+	incq %rax		/* increment pointer */
+
+	shrq $32, %rcx		/* look at other half.  */
+
+	testb %cl, %cl		/* is first byte NUL? */
+	jz 2f			/* yes => return */
+	incq %rax		/* increment pointer */
+
+	testb %ch, %ch		/* is second byte NUL? */
+	jz 2f			/* yes => return */
+	incq %rax		/* increment pointer */
+
+	testl $0xff0000, %ecx	/* is third byte NUL? */
+	jz 2f			/* yes => return pointer */
+	incq %rax		/* increment pointer */
+
+2:
+	/* Second step: Copy source to destination.  */
+
+	movq	%rsi, %rcx	/* duplicate  */
+	andl	$7,%ecx		/* mask alignment bits */
+	movq	%rax, %rdx	/* move around */
+	jz	22f		/* aligned => start loop */
+
+	neg	%ecx		/* align to 8 bytes.  */
+	addl	$8, %ecx
+	/* Align the source pointer.  */
+21:
+	movb	(%rsi), %al	/* Fetch a byte */
+	testb	%al, %al	/* Is it NUL? */
+	movb	%al, (%rdx)	/* Store it */
+	jz	24f		/* If it was NUL, done! */
+	incq	%rsi
+	incq	%rdx
+	decl	%ecx
+	jnz	21b
+
+	/* Now the sources is aligned.  Unfortunatly we cannot force
+	   to have both source and destination aligned, so ignore the
+	   alignment of the destination.  */
+	.p2align 4
+22:
+	/* 1st unroll.  */
+	movq	(%rsi), %rax	/* Read double word (8 bytes).  */
+	addq	$8, %rsi	/* Adjust pointer for next word.  */
+	movq	%rax, %r9	/* Save a copy for NUL finding.  */
+	addq	%r8, %r9	/* add the magic value to the word.  We get
+				   carry bits reported for each byte which
+				   is *not* 0 */
+	jnc	23f		/* highest byte is NUL => return pointer */
+	xorq	%rax, %r9	/* (word+magic)^word */
+	orq	%r8, %r9	/* set all non-carry bits */
+	incq	%r9		/* add 1: if one carry bit was *not* set
+				   the addition will not result in 0.  */
+
+	jnz	23f		/* found NUL => return pointer */
+
+	movq	%rax, (%rdx)	/* Write value to destination.  */
+	addq	$8, %rdx	/* Adjust pointer.  */
+
+	/* 2nd unroll.  */
+	movq	(%rsi), %rax	/* Read double word (8 bytes).  */
+	addq	$8, %rsi	/* Adjust pointer for next word.  */
+	movq	%rax, %r9	/* Save a copy for NUL finding.  */
+	addq	%r8, %r9	/* add the magic value to the word.  We get
+				   carry bits reported for each byte which
+				   is *not* 0 */
+	jnc	23f		/* highest byte is NUL => return pointer */
+	xorq	%rax, %r9	/* (word+magic)^word */
+	orq	%r8, %r9	/* set all non-carry bits */
+	incq	%r9		/* add 1: if one carry bit was *not* set
+				   the addition will not result in 0.  */
+
+	jnz	23f		/* found NUL => return pointer */
+
+	movq	%rax, (%rdx)	/* Write value to destination.  */
+	addq	$8, %rdx	/* Adjust pointer.  */
+
+	/* 3rd unroll.  */
+	movq	(%rsi), %rax	/* Read double word (8 bytes).  */
+	addq	$8, %rsi	/* Adjust pointer for next word.  */
+	movq	%rax, %r9	/* Save a copy for NUL finding.  */
+	addq	%r8, %r9	/* add the magic value to the word.  We get
+				   carry bits reported for each byte which
+				   is *not* 0 */
+	jnc	23f		/* highest byte is NUL => return pointer */
+	xorq	%rax, %r9	/* (word+magic)^word */
+	orq	%r8, %r9	/* set all non-carry bits */
+	incq	%r9		/* add 1: if one carry bit was *not* set
+				   the addition will not result in 0.  */
+
+	jnz	23f		/* found NUL => return pointer */
+
+	movq	%rax, (%rdx)	/* Write value to destination.  */
+	addq	$8, %rdx	/* Adjust pointer.  */
+
+	/* 4th unroll.  */
+	movq	(%rsi), %rax	/* Read double word (8 bytes).  */
+	addq	$8, %rsi	/* Adjust pointer for next word.  */
+	movq	%rax, %r9	/* Save a copy for NUL finding.  */
+	addq	%r8, %r9	/* add the magic value to the word.  We get
+				   carry bits reported for each byte which
+				   is *not* 0 */
+	jnc	23f		/* highest byte is NUL => return pointer */
+	xorq	%rax, %r9	/* (word+magic)^word */
+	orq	%r8, %r9	/* set all non-carry bits */
+	incq	%r9		/* add 1: if one carry bit was *not* set
+				   the addition will not result in 0.  */
+
+	jnz	23f		/* found NUL => return pointer */
+
+	movq	%rax, (%rdx)	/* Write value to destination.  */
+	addq	$8, %rdx	/* Adjust pointer.  */
+	jmp	22b		/* Next iteration.  */
+
+	/* Do the last few bytes. %rax contains the value to write.
+	   The loop is unrolled twice.  */
+	.p2align 4
+23:
+	movb	%al, (%rdx)	/* 1st byte.  */
+	testb	%al, %al	/* Is it NUL.  */
+	jz	24f		/* yes, finish.  */
+	incq	%rdx		/* Increment destination.  */
+	movb	%ah, (%rdx)	/* 2nd byte.  */
+	testb	%ah, %ah	/* Is it NUL?.  */
+	jz	24f		/* yes, finish.  */
+	incq	%rdx		/* Increment destination.  */
+	shrq	$16, %rax	/* Shift...  */
+	jmp	23b		/* and look at next two bytes in %rax.  */
+
+
+24:
+	movq	%rdi, %rax	/* Source is return value.  */
+	retq
+END (BP_SYM (strcat))
diff --git a/libc/string/x86_64/strchr.S b/libc/string/x86_64/strchr.S
new file mode 100644
index 000000000..b84b012b2
--- /dev/null
+++ b/libc/string/x86_64/strchr.S
@@ -0,0 +1,287 @@
+/* strchr (str, ch) -- Return pointer to first occurrence of CH in STR.
+   For AMD x86-64.
+   Copyright (C) 2002, 2005 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include "_glibc_inc.h"
+
+
+	.text
+ENTRY (BP_SYM (strchr))
+
+	/* Before we start with the main loop we process single bytes
+	   until the source pointer is aligned.  This has two reasons:
+	   1. aligned 64-bit memory access is faster
+	   and (more important)
+	   2. we process in the main loop 64 bit in one step although
+	      we don't know the end of the string.  But accessing at
+	      8-byte alignment guarantees that we never access illegal
+	      memory if this would not also be done by the trivial
+	      implementation (this is because all processor inherent
+	      boundaries are multiples of 8).  */
+
+	movq	%rdi, %rdx
+	andl	$7, %edx	/* Mask alignment bits  */
+	movq	%rdi, %rax	/* duplicate destination.  */
+	jz	1f		/* aligned => start loop */
+	neg	%edx
+	addl	$8, %edx	/* Align to 8 bytes.  */
+
+	/* Search the first bytes directly.  */
+0:	movb	(%rax), %cl	/* load byte  */
+	cmpb	%cl,%sil	/* compare byte.  */
+	je	6f		/* target found */
+	testb	%cl,%cl		/* is byte NUL? */
+	je	7f		/* yes => return NULL */
+	incq	%rax		/* increment pointer */
+	decl	%edx
+	jnz	0b
+
+
+1:
+	/* At the moment %rsi contains C.  What we need for the
+	   algorithm is C in all bytes of the register.  Avoid
+	   operations on 16 bit words because these require an
+	   prefix byte (and one more cycle).  */
+	/* Populate 8 bit data to full 64-bit.  */
+	movabs	$0x0101010101010101,%r9
+	movzbl	%sil,%edx
+	imul	%rdx,%r9
+
+	movq $0xfefefefefefefeff, %r8 /* Save magic.  */
+
+      /* We exit the loop if adding MAGIC_BITS to LONGWORD fails to
+	 change any of the hole bits of LONGWORD.
+
+	 1) Is this safe?  Will it catch all the zero bytes?
+	 Suppose there is a byte with all zeros.  Any carry bits
+	 propagating from its left will fall into the hole at its
+	 least significant bit and stop.  Since there will be no
+	 carry from its most significant bit, the LSB of the
+	 byte to the left will be unchanged, and the zero will be
+	 detected.
+
+	 2) Is this worthwhile?  Will it ignore everything except
+	 zero bytes?  Suppose every byte of QUARDWORD has a bit set
+	 somewhere.  There will be a carry into bit 8.	If bit 8
+	 is set, this will carry into bit 16.  If bit 8 is clear,
+	 one of bits 9-15 must be set, so there will be a carry
+	 into bit 16.  Similarly, there will be a carry into bit
+	 24 tec..  If one of bits 54-63 is set, there will be a carry
+	 into bit 64 (=carry flag), so all of the hole bits will
+	 be changed.
+
+	 3) But wait!  Aren't we looking for C, not zero?
+	 Good point.  So what we do is XOR LONGWORD with a longword,
+	 each of whose bytes is C.  This turns each byte that is C
+	 into a zero.  */
+
+	.p2align 4
+4:
+	/* Main Loop is unrolled 4 times.  */
+	/* First unroll.  */
+	movq (%rax), %rcx	/* get double word (= 8 bytes) in question */
+	addq $8,%rax		/* adjust pointer for next word */
+	movq %r8, %rdx		/* magic value */
+	xorq %r9, %rcx		/* XOR with qword c|...|c => bytes of str == c
+				   are now 0 */
+	addq %rcx, %rdx		/* add the magic value to the word.  We get
+				   carry bits reported for each byte which
+				   is *not* 0 */
+	jnc 3f			/* highest byte is NUL => return pointer */
+	xorq %rcx, %rdx		/* (word+magic)^word */
+	orq %r8, %rdx		/* set all non-carry bits */
+	incq %rdx		/* add 1: if one carry bit was *not* set
+				   the addition will not result in 0.  */
+	jnz 3f			/* found c => return pointer */
+
+	/* The quadword we looked at does not contain the value we're looking
+	   for.  Let's search now whether we have reached the end of the
+	   string.  */
+	xorq %r9, %rcx		/* restore original dword without reload */
+	movq %r8, %rdx		/* magic value */
+	addq %rcx, %rdx		/* add the magic value to the word.  We get
+				   carry bits reported for each byte which
+				   is *not* 0 */
+	jnc 7f			/* highest byte is NUL => return NULL */
+	xorq %rcx, %rdx		/* (word+magic)^word */
+	orq %r8, %rdx		/* set all non-carry bits */
+	incq %rdx		/* add 1: if one carry bit was *not* set
+				   the addition will not result in 0.  */
+	jnz 7f			/* found NUL => return NULL */
+
+	/* Second unroll.  */
+	movq (%rax), %rcx	/* get double word (= 8 bytes) in question */
+	addq $8,%rax		/* adjust pointer for next word */
+	movq %r8, %rdx		/* magic value */
+	xorq %r9, %rcx		/* XOR with qword c|...|c => bytes of str == c
+				   are now 0 */
+	addq %rcx, %rdx		/* add the magic value to the word.  We get
+				   carry bits reported for each byte which
+				   is *not* 0 */
+	jnc 3f			/* highest byte is NUL => return pointer */
+	xorq %rcx, %rdx		/* (word+magic)^word */
+	orq %r8, %rdx		/* set all non-carry bits */
+	incq %rdx		/* add 1: if one carry bit was *not* set
+				   the addition will not result in 0.  */
+	jnz 3f			/* found c => return pointer */
+
+	/* The quadword we looked at does not contain the value we're looking
+	   for.  Let's search now whether we have reached the end of the
+	   string.  */
+	xorq %r9, %rcx		/* restore original dword without reload */
+	movq %r8, %rdx		/* magic value */
+	addq %rcx, %rdx		/* add the magic value to the word.  We get
+				   carry bits reported for each byte which
+				   is *not* 0 */
+	jnc 7f			/* highest byte is NUL => return NULL */
+	xorq %rcx, %rdx		/* (word+magic)^word */
+	orq %r8, %rdx		/* set all non-carry bits */
+	incq %rdx		/* add 1: if one carry bit was *not* set
+				   the addition will not result in 0.  */
+	jnz 7f			/* found NUL => return NULL */
+	/* Third unroll.  */
+	movq (%rax), %rcx	/* get double word (= 8 bytes) in question */
+	addq $8,%rax		/* adjust pointer for next word */
+	movq %r8, %rdx		/* magic value */
+	xorq %r9, %rcx		/* XOR with qword c|...|c => bytes of str == c
+				   are now 0 */
+	addq %rcx, %rdx		/* add the magic value to the word.  We get
+				   carry bits reported for each byte which
+				   is *not* 0 */
+	jnc 3f			/* highest byte is NUL => return pointer */
+	xorq %rcx, %rdx		/* (word+magic)^word */
+	orq %r8, %rdx		/* set all non-carry bits */
+	incq %rdx		/* add 1: if one carry bit was *not* set
+				   the addition will not result in 0.  */
+	jnz 3f			/* found c => return pointer */
+
+	/* The quadword we looked at does not contain the value we're looking
+	   for.  Let's search now whether we have reached the end of the
+	   string.  */
+	xorq %r9, %rcx		/* restore original dword without reload */
+	movq %r8, %rdx		/* magic value */
+	addq %rcx, %rdx		/* add the magic value to the word.  We get
+				   carry bits reported for each byte which
+				   is *not* 0 */
+	jnc 7f			/* highest byte is NUL => return NULL */
+	xorq %rcx, %rdx		/* (word+magic)^word */
+	orq %r8, %rdx		/* set all non-carry bits */
+	incq %rdx		/* add 1: if one carry bit was *not* set
+				   the addition will not result in 0.  */
+	jnz 7f			/* found NUL => return NULL */
+	/* Fourth unroll.  */
+	movq (%rax), %rcx	/* get double word (= 8 bytes) in question */
+	addq $8,%rax		/* adjust pointer for next word */
+	movq %r8, %rdx		/* magic value */
+	xorq %r9, %rcx		/* XOR with qword c|...|c => bytes of str == c
+				   are now 0 */
+	addq %rcx, %rdx		/* add the magic value to the word.  We get
+				   carry bits reported for each byte which
+				   is *not* 0 */
+	jnc 3f			/* highest byte is NUL => return pointer */
+	xorq %rcx, %rdx		/* (word+magic)^word */
+	orq %r8, %rdx		/* set all non-carry bits */
+	incq %rdx		/* add 1: if one carry bit was *not* set
+				   the addition will not result in 0.  */
+	jnz 3f			/* found c => return pointer */
+
+	/* The quadword we looked at does not contain the value we're looking
+	   for.  Let's search now whether we have reached the end of the
+	   string.  */
+	xorq %r9, %rcx		/* restore original dword without reload */
+	movq %r8, %rdx		/* magic value */
+	addq %rcx, %rdx		/* add the magic value to the word.  We get
+				   carry bits reported for each byte which
+				   is *not* 0 */
+	jnc 7f			/* highest byte is NUL => return NULL */
+	xorq %rcx, %rdx		/* (word+magic)^word */
+	orq %r8, %rdx		/* set all non-carry bits */
+	incq %rdx		/* add 1: if one carry bit was *not* set
+				   the addition will not result in 0.  */
+	jz 4b			/* no NUL found => restart loop */
+
+
+7:	/* Return NULL.  */
+	xorl %eax, %eax
+	retq
+
+
+	/* We now scan for the byte in which the character was matched.
+	   But we have to take care of the case that a NUL char is
+	   found before this in the dword.  Note that we XORed %rcx
+	   with the byte we're looking for, therefore the tests below look
+	   reversed.  */
+
+
+	.p2align 4		/* Align, it's a jump target.  */
+3:	movq	%r9,%rdx	/* move to %rdx so that we can access bytes */
+	subq	$8,%rax		/* correct pointer increment.  */
+	testb %cl, %cl		/* is first byte C? */
+	jz 6f			/* yes => return pointer */
+	cmpb %dl, %cl		/* is first byte NUL? */
+	je 7b			/* yes => return NULL */
+	incq %rax		/* increment pointer */
+
+	testb %ch, %ch		/* is second byte C? */
+	jz 6f			/* yes => return pointer */
+	cmpb %dl, %ch		/* is second byte NUL? */
+	je 7b			/* yes => return NULL? */
+	incq %rax		/* increment pointer */
+
+	shrq $16, %rcx		/* make upper bytes accessible */
+	testb %cl, %cl		/* is third byte C? */
+	jz 6f			/* yes => return pointer */
+	cmpb %dl, %cl		/* is third byte NUL? */
+	je 7b			/* yes => return NULL */
+	incq %rax		/* increment pointer */
+
+	testb %ch, %ch		/* is fourth byte C? */
+	jz 6f			/* yes => return pointer */
+	cmpb %dl, %ch		/* is fourth byte NUL? */
+	je 7b			/* yes => return NULL? */
+	incq %rax		/* increment pointer */
+
+	shrq $16, %rcx		/* make upper bytes accessible */
+	testb %cl, %cl		/* is fifth byte C? */
+	jz 6f			/* yes => return pointer */
+	cmpb %dl, %cl		/* is fifth byte NUL? */
+	je 7b			/* yes => return NULL */
+	incq %rax		/* increment pointer */
+
+	testb %ch, %ch		/* is sixth byte C? */
+	jz 6f			/* yes => return pointer */
+	cmpb %dl, %ch		/* is sixth byte NUL? */
+	je 7b			/* yes => return NULL? */
+	incq %rax		/* increment pointer */
+
+	shrq $16, %rcx		/* make upper bytes accessible */
+	testb %cl, %cl		/* is seventh byte C? */
+	jz 6f			/* yes => return pointer */
+	cmpb %dl, %cl		/* is seventh byte NUL? */
+	je 7b			/* yes => return NULL */
+
+	/* It must be in the eigth byte and it cannot be NUL.  */
+	incq %rax
+
+6:
+	nop
+	retq
+END (BP_SYM (strchr))
+
+weak_alias (BP_SYM (strchr), BP_SYM (index))
diff --git a/libc/string/x86_64/strcmp.S b/libc/string/x86_64/strcmp.S
new file mode 100644
index 000000000..0b401a773
--- /dev/null
+++ b/