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authorAndreas Jaeger <aj@suse.de>2002-08-31 17:45:33 +0000
committerAndreas Jaeger <aj@suse.de>2002-08-31 17:45:33 +0000
commit78df0fcb80247ca7573a8ed07cc992b7031674c1 (patch)
tree339b581727c7ae5782f5118bf98567acda987553 /sysdeps/x86_64/strcpy.S
parent7c9466bc7688e084cfbf9311eb91bdbaed1ea888 (diff)
downloadglibc-78df0fcb80247ca7573a8ed07cc992b7031674c1.tar.gz
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Update.
	* sysdeps/x86_64/dl-machine.h (elf_machine_runtime_setup): Declare
	external functions with hidden attribute.
	(elf_machine_rela): Optimize.

	* sysdeps/x86_64/memset.S: New file.
	* sysdeps/x86_64/bzero.S: New file.
	* sysdeps/x86_64/stpcpy.S: New file.
	* sysdeps/x86_64/strcat.S: New file.
	* sysdeps/x86_64/strchr.S: New file.
	* sysdeps/x86_64/strcpy.S: New file.
	* sysdeps/x86_64/strcspn.S: New file.
	* sysdeps/x86_64/strlen.S: New file.
	* sysdeps/x86_64/strpbrk.S: New file.
	* sysdeps/x86_64/strspn.S: New file.
	* sysdeps/x86_64/strcmp.S: New file.
	* sysdeps/x86_64/strtok_r.S: New file.
	* sysdeps/x86_64/strtok.S: New file.
	* sysdeps/x86_64/memcpy.S: New file.
	* sysdeps/x86_64/mempcpy.S: New file.
Diffstat (limited to 'sysdeps/x86_64/strcpy.S')
-rw-r--r--sysdeps/x86_64/strcpy.S156
1 files changed, 156 insertions, 0 deletions
diff --git a/sysdeps/x86_64/strcpy.S b/sysdeps/x86_64/strcpy.S
new file mode 100644
index 0000000000..f178b9b69c
--- /dev/null
+++ b/sysdeps/x86_64/strcpy.S
@@ -0,0 +1,156 @@
+/* strcpy/stpcpy implementation 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 <sysdep.h>
+#include "asm-syntax.h"
+#include "bp-sym.h"
+#include "bp-asm.h"
+
+#ifndef USE_AS_STPCPY
+# define STRCPY strcpy
+#endif
+
+	.text
+ENTRY (BP_SYM (STRCPY))
+	movq %rsi, %rcx		/* Source register. */
+	andl $7, %ecx		/* mask alignment bits */
+	movq %rdi, %rdx		/* Duplicate destination pointer.  */
+
+	jz 5f			/* aligned => start loop */
+
+	neg %ecx		/* We need to align to 8 bytes.  */
+	addl $8,%ecx
+	/* Search the first bytes directly.  */
+0:
+	movb	(%rsi), %al	/* Fetch a byte */
+	testb	%al, %al	/* Is it NUL? */
+	movb	%al, (%rdx)	/* Store it */
+	jz	4f		/* If it was NUL, done! */
+	incq	%rsi
+	incq	%rdx
+	decl	%ecx
+	jnz	0b
+
+5:
+	movq $0xfefefefefefefeff,%r8
+
+	/* 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
+1:
+	/* 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	3f		/* 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	3f		/* 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	3f		/* 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	3f		/* 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	3f		/* 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	3f		/* 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	3f		/* 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	3f		/* found NUL => return pointer */
+
+	movq	%rax, (%rdx)	/* Write value to destination.  */
+	addq	$8, %rdx	/* Adjust pointer.  */
+	jmp	1b		/* Next iteration.  */
+
+	/* Do the last few bytes. %rax contains the value to write.
+	   The loop is unrolled twice.  */
+	.p2align 4
+3:
+	/* Note that stpcpy needs to return with the value of the NUL
+	   byte.  */
+	movb	%al, (%rdx)	/* 1st byte.  */
+	testb	%al, %al	/* Is it NUL.  */
+	jz	4f		/* yes, finish.  */
+	incq	%rdx		/* Increment destination.  */
+	movb	%ah, (%rdx)	/* 2nd byte.  */
+	testb	%ah, %ah	/* Is it NUL?.  */
+	jz	4f		/* yes, finish.  */
+	incq	%rdx		/* Increment destination.  */
+	shrq	$16, %rax	/* Shift...  */
+	jmp	3b		/* and look at next two bytes in %rax.  */
+
+4:
+#ifdef USE_AS_STPCPY
+	movq	%rdx, %rax	/* Destination is return value.  */
+#else
+	movq	%rdi, %rax	/* Source is return value.  */
+#endif
+	retq
+END (BP_SYM (STRCPY))