Move i486/strcat.S to strcat.S

Since glibc doesn't support i386 any more, we can move i486/strcat.S
to strcat.S.

	* sysdeps/i386/i486/strcat.S: Moved to ...
	* sysdeps/i386/strcat.S: Here.
	* sysdeps/i386/i686/multiarch/strcat.S: Updated.

1 files changed, 265 insertions, 0 deletions

diff --git a/sysdeps/i386/strcat.S b/sysdeps/i386/strcat.S
new file mode 100644
index 0000000000..88c29fb572
--- /dev/null
+++ b/sysdeps/i386/strcat.S
@@ -0,0 +1,265 @@
+/* strcat(dest, src) -- Append SRC on the end of DEST.
+   For Intel 80x86, x>=4.
+   Copyright (C) 1994-2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@ipd.info.uni-karlsruhe.de>.
+   Optimised a little by Alan Modra <Alan@SPRI.Levels.UniSA.Edu.Au>
+
+   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, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <sysdep.h>
+#include "asm-syntax.h"
+
+#define PARMS	4+4	/* space for 1 saved reg */
+#define RTN	PARMS
+#define DEST	RTN
+#define SRC	DEST+4
+
+	.text
+ENTRY (strcat)
+
+	pushl %edi		/* Save callee-safe register.  */
+	cfi_adjust_cfa_offset (4)
+
+	movl DEST(%esp), %edx
+	movl SRC(%esp), %ecx
+
+	testb $0xff, (%ecx)	/* Is source string empty? */
+	jz L(8)			/* yes => return */
+
+	/* Test the first bytes separately until destination is aligned.  */
+	testl $3, %edx		/* destination pointer aligned? */
+	jz L(1)			/* yes => begin scan loop */
+	testb $0xff, (%edx)	/* is end of string? */
+	jz L(2)			/* yes => start appending */
+	incl %edx		/* increment source pointer */
+
+	testl $3, %edx		/* destination pointer aligned? */
+	jz L(1)			/* yes => begin scan loop */
+	testb $0xff, (%edx)	/* is end of string? */
+	jz L(2)			/* yes => start appending */
+	incl %edx		/* increment source pointer */
+
+	testl $3, %edx		/* destination pointer aligned? */
+	jz L(1)			/* yes => begin scan loop */
+	testb $0xff, (%edx)	/* is end of string? */
+	jz L(2)			/* yes => start appending */
+	incl %edx		/* increment source pointer */
+
+	/* Now we are aligned.  Begin scan loop.  */
+	jmp L(1)
+
+	cfi_rel_offset (edi, 0)
+	ALIGN(4)
+
+L(4):	addl $16,%edx		/* increment destination pointer for round */
+
+L(1):	movl (%edx), %eax	/* get word (= 4 bytes) in question */
+	movl $0xfefefeff, %edi	/* magic value */
+
+	/* If you compare this with the algorithm in memchr.S you will
+	   notice that here is an `xorl' statement missing.  But you must
+	   not forget that we are looking for C == 0 and `xorl $0, %eax'
+	   is a no-op.  */
+
+	addl %eax, %edi		/* add the magic value to the word.  We get
+				   carry bits reported for each byte which
+				   is *not* 0 */
+
+	/* According to the algorithm we had to reverse the effect of the
+	   XOR first and then test the overflow bits.  But because the
+	   following XOR would destroy the carry flag and it would (in a
+	   representation with more than 32 bits) not alter then last
+	   overflow, we can now test this condition.  If no carry is signaled
+	   no overflow must have occurred in the last byte => it was 0.	*/
+	jnc L(3)
+
+	/* We are only interested in carry bits that change due to the
+	   previous add, so remove original bits */
+	xorl %eax, %edi		/* ((word^charmask)+magic)^(word^charmask) */
+
+	/* Now test for the other three overflow bits.  */
+	orl $0xfefefeff, %edi	/* set all non-carry bits */
+	incl %edi		/* add 1: if one carry bit was *not* set
+				   the addition will not result in 0.  */
+
+	/* If at least one byte of the word is C we don't get 0 in %ecx.  */
+	jnz L(3)
+
+	movl 4(%edx), %eax	/* get word from source */
+	movl $0xfefefeff, %edi	/* magic value */
+	addl %eax, %edi		/* add the magic value to the word.  We get
+				   carry bits reported for each byte which
+				   is *not* 0 */
+	jnc L(5)		/* highest byte is C => stop copying */
+	xorl %eax, %edi		/* ((word^charmask)+magic)^(word^charmask) */
+	orl $0xfefefeff, %edi	/* set all non-carry bits */
+	incl %edi		/* add 1: if one carry bit was *not* set
+				   the addition will not result in 0.  */
+	jnz L(5)		/* one byte is NUL => stop copying */
+
+	movl 8(%edx), %eax	/* get word from source */
+	movl $0xfefefeff, %edi	/* magic value */
+	addl %eax, %edi		/* add the magic value to the word.  We get
+				   carry bits reported for each byte which
+				   is *not* 0 */
+	jnc L(6)		/* highest byte is C => stop copying */
+	xorl %eax, %edi		/* ((word^charmask)+magic)^(word^charmask) */
+	orl $0xfefefeff, %edi	/* set all non-carry bits */
+	incl %edi		/* add 1: if one carry bit was *not* set
+				   the addition will not result in 0.  */
+	jnz L(6)		/* one byte is NUL => stop copying */
+
+	movl 12(%edx), %eax	/* get word from source */
+	movl $0xfefefeff, %edi	/* magic value */
+	addl %eax, %edi		/* add the magic value to the word.  We get
+				   carry bits reported for each byte which
+				   is *not* 0 */
+	jnc L(7)		/* highest byte is C => stop copying */
+	xorl %eax, %edi		/* ((word^charmask)+magic)^(word^charmask) */
+	orl $0xfefefeff, %edi	/* set all non-carry bits */
+	incl %edi		/* add 1: if one carry bit was *not* set
+				   the addition will not result in 0.  */
+	jz L(4)			/* no byte is NUL => carry on copying */
+
+L(7):	addl $4, %edx		/* adjust source pointer */
+L(6):	addl $4, %edx
+L(5):	addl $4, %edx
+
+L(3):	testb %al, %al		/* is first byte NUL? */
+	jz L(2)			/* yes => start copying */
+	incl %edx		/* increment source pointer */
+
+	testb %ah, %ah		/* is second byte NUL? */
+	jz L(2)			/* yes => start copying */
+	incl %edx		/* increment source pointer */
+
+	testl $0xff0000, %eax	/* is third byte NUL? */
+	jz L(2)			/* yes => start copying */
+	incl %edx		/* increment source pointer */
+
+L(2):	subl %ecx, %edx		/* reduce number of loop variants */
+
+	/* Now we have to align the source pointer.  */
+	testl $3, %ecx		/* pointer correctly aligned? */
+	jz L(29)		/* yes => start copy loop */
+	movb (%ecx), %al	/* get first byte */
+	movb %al, (%ecx,%edx)	/* and store it */
+	andb %al, %al		/* is byte NUL? */
+	jz L(8)			/* yes => return */
+	incl %ecx		/* increment pointer */
+
+	testl $3, %ecx		/* pointer correctly aligned? */
+	jz L(29)		/* yes => start copy loop */
+	movb (%ecx), %al	/* get first byte */
+	movb %al, (%ecx,%edx)	/* and store it */
+	andb %al, %al		/* is byte NUL? */
+	jz L(8)			/* yes => return */
+	incl %ecx		/* increment pointer */
+
+	testl $3, %ecx		/* pointer correctly aligned? */
+	jz L(29)		/* yes => start copy loop */
+	movb (%ecx), %al	/* get first byte */
+	movb %al, (%ecx,%edx)	/* and store it */
+	andb %al, %al		/* is byte NUL? */
+	jz L(8)			/* yes => return */
+	incl %ecx		/* increment pointer */
+
+	/* Now we are aligned.  */
+	jmp L(29)		/* start copy loop */
+
+	ALIGN(4)
+
+L(28):	movl %eax, 12(%ecx,%edx)/* store word at destination */
+	addl $16, %ecx		/* adjust pointer for full round */
+
+L(29):	movl (%ecx), %eax	/* get word from source */
+	movl $0xfefefeff, %edi	/* magic value */
+	addl %eax, %edi		/* add the magic value to the word.  We get
+				   carry bits reported for each byte which
+				   is *not* 0 */
+	jnc L(9)		/* highest byte is C => stop copying */
+	xorl %eax, %edi		/* ((word^charmask)+magic)^(word^charmask) */
+	orl $0xfefefeff, %edi	/* set all non-carry bits */
+	incl %edi		/* add 1: if one carry bit was *not* set
+				   the addition will not result in 0.  */
+	jnz L(9)		/* one byte is NUL => stop copying */
+	movl %eax, (%ecx,%edx)	/* store word to destination */
+
+	movl 4(%ecx), %eax	/* get word from source */
+	movl $0xfefefeff, %edi	/* magic value */
+	addl %eax, %edi		/* add the magic value to the word.  We get
+				   carry bits reported for each byte which
+				   is *not* 0 */
+	jnc L(91)		/* highest byte is C => stop copying */
+	xorl %eax, %edi		/* ((word^charmask)+magic)^(word^charmask) */
+	orl $0xfefefeff, %edi	/* set all non-carry bits */
+	incl %edi		/* add 1: if one carry bit was *not* set
+				   the addition will not result in 0.  */
+	jnz L(91)		/* one byte is NUL => stop copying */
+	movl %eax, 4(%ecx,%edx)	/* store word to destination */
+
+	movl 8(%ecx), %eax	/* get word from source */
+	movl $0xfefefeff, %edi	/* magic value */
+	addl %eax, %edi		/* add the magic value to the word.  We get
+				   carry bits reported for each byte which
+				   is *not* 0 */
+	jnc L(92)		/* highest byte is C => stop copying */
+	xorl %eax, %edi		/* ((word^charmask)+magic)^(word^charmask) */
+	orl $0xfefefeff, %edi	/* set all non-carry bits */
+	incl %edi		/* add 1: if one carry bit was *not* set
+				   the addition will not result in 0.  */
+	jnz L(92)		/* one byte is NUL => stop copying */
+	movl %eax, 8(%ecx,%edx)	/* store word to destination */
+
+	movl 12(%ecx), %eax	/* get word from source */
+	movl $0xfefefeff, %edi	/* magic value */
+	addl %eax, %edi		/* add the magic value to the word.  We get
+				   carry bits reported for each byte which
+				   is *not* 0 */
+	jnc L(93)		/* highest byte is C => stop copying */
+	xorl %eax, %edi		/* ((word^charmask)+magic)^(word^charmask) */
+	orl $0xfefefeff, %edi	/* set all non-carry bits */
+	incl %edi		/* add 1: if one carry bit was *not* set
+				   the addition will not result in 0.  */
+	jz L(28)		/* no is NUL => carry on copying */
+
+L(93):	addl $4, %ecx		/* adjust pointer */
+L(92):	addl $4, %ecx
+L(91):	addl $4, %ecx
+
+L(9):	movb %al, (%ecx,%edx)	/* store first byte of last word */
+	orb %al, %al		/* is it NUL? */
+	jz L(8)			/* yes => return */
+
+	movb %ah, 1(%ecx,%edx)	/* store second byte of last word */
+	orb %ah, %ah		/* is it NUL? */
+	jz L(8)			/* yes => return */
+
+	shrl $16, %eax		/* make upper bytes accessible */
+	movb %al, 2(%ecx,%edx)	/* store third byte of last word */
+	orb %al, %al		/* is it NUL? */
+	jz L(8)			/* yes => return */
+
+	movb %ah, 3(%ecx,%edx)	/* store fourth byte of last word */
+
+L(8):	movl DEST(%esp), %eax	/* start address of destination is result */
+	popl %edi		/* restore saved register */
+	cfi_adjust_cfa_offset (-4)
+	cfi_restore (edi)
+
+	ret
+END (strcat)
+libc_hidden_builtin_def (strcat)