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-rw-r--r--sysdeps/sparc/sparc32/stpcpy.S163
1 files changed, 163 insertions, 0 deletions
diff --git a/sysdeps/sparc/sparc32/stpcpy.S b/sysdeps/sparc/sparc32/stpcpy.S
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+++ b/sysdeps/sparc/sparc32/stpcpy.S
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+/* Copy SRC to DEST returning the address of the terminating '\0' in DEST.
+   For SPARC v7.
+   Copyright (C) 1996, 1999 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Jakub Jelinek <jj@ultra.linux.cz>.
+
+   The GNU C Library 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.
+
+   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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include <sysdep.h>
+
+	/* Normally, this uses ((xword - 0x01010101) & 0x80808080) test
+	   to find out if any byte in xword could be zero. This is fast, but
+	   also gives false alarm for any byte in range 0x81-0xff. It does
+	   not matter for correctness, as if this test tells us there could
+	   be some zero byte, we check it byte by byte, but if bytes with
+	   high bits set are common in the strings, then this will give poor
+	   performance. You can #define EIGHTBIT_NOT_RARE and the algorithm
+	   will use one tick slower, but more precise test
+	   ((xword - 0x01010101) & (~xword) & 0x80808080),
+	   which does not give any false alarms (but if some bits are set,
+	   one cannot assume from it which bytes are zero and which are not).
+	   It is yet to be measured, what is the correct default for glibc
+	   in these days for an average user.
+	 */
+
+	.text
+	.align		4
+10:	ldub		[%o1], %o5
+	stb		%o5, [%o0]
+	cmp		%o5, 0
+	add		%o0, 1, %o0
+	be		1f
+	 add		%o1, 1, %o1
+	andcc		%o1, 3, %g0
+	be		4f
+	 or		%o4, %lo(0x80808080), %o3
+	ldub		[%o1], %o5
+	stb		%o5, [%o0]
+	cmp		%o5, 0
+	add		%o0, 1, %o0
+	be		1f
+	 add		%o1, 1, %o1
+	andcc		%o1, 3, %g0
+	be		5f
+	 sethi		%hi(0x01010101), %o4
+	ldub		[%o1], %o5
+	stb		%o5, [%o0]
+	cmp		%o5, 0
+	add		%o0, 1, %o0
+	be		1f
+	 add		%o1, 1, %o1
+	b		6f
+	 or		%o4, %lo(0x01010101), %o2
+1:	retl
+	 add		%o0, -1, %o0
+
+ENTRY(__stpcpy)
+	andcc		%o1, 3, %g0
+	bne		10b
+	 sethi		%hi(0x80808080), %o4
+	or		%o4, %lo(0x80808080), %o3
+4:	sethi		%hi(0x01010101), %o4
+5:	or		%o4, %lo(0x01010101), %o2
+6:	andcc		%o0, 3, %g0
+	bne		16f
+	 sub		%g0, 4, %g1
+	 
+11:	add		%g1, 4, %g1
+	ld		[%o1 + %g1], %o5
+	sub		%o5, %o2, %o4
+#ifdef EIGHTBIT_NOT_RARE
+	andn		%o4, %o5, %o4
+#endif
+	andcc		%o4, %o3, %g0
+	be,a		11b
+	 st		%o5, [%o0 + %g1]
+
+	/* Check every byte. */
+	srl		%o5, 24, %g5
+	andcc		%g5, 0xff, %g0
+	be		14f
+	 srl		%o5, 16, %g5
+	andcc		%g5, 0xff, %g0
+	be		13f
+	 srl		%o5, 8, %g5
+	andcc		%g5, 0xff, %g0
+	be		12f
+	 andcc		%o5, 0xff, %g0
+	bne		11b
+	 st		%o5, [%o0 + %g1]
+	add		%o0, %g1, %o0
+	retl
+	 add		%o0, 3, %o0
+12:	srl		%o5, 16, %o5
+	sth		%o5, [%o0 + %g1]
+	add		%g1, 2, %g1
+	stb		%g0, [%o0 + %g1]
+	retl
+	 add		%o0, %g1, %o0
+13:	srl		%o5, 16, %o5
+	sth		%o5, [%o0 + %g1]
+	add		%g1, 1, %g1
+	retl
+	 add		%o0, %g1, %o0
+14:	stb		%g0, [%o0 + %g1]
+	retl
+	 add		%o0, %g1, %o0
+
+15:	srl		%o5, 24, %o4
+	srl		%o5, 16, %g1
+	stb		%o4, [%o0]
+	srl		%o5, 8, %g4
+	stb		%g1, [%o0 + 1]
+	stb		%g4, [%o0 + 2]
+	stb		%o5, [%o0 + 3]
+	add		%o0, 4, %o0
+16:	ld		[%o1], %o5
+	sub		%o5, %o2, %o4
+	andcc		%o4, %o3, %g0
+	be		15b
+	 add		%o1, 4, %o1
+
+	/* Check every byte. */
+	srl		%o5, 24, %g5
+	andcc		%g5, 0xff, %g4
+	be		19f
+	 stb		%g4, [%o0]
+	srl		%o5, 16, %g5
+	andcc		%g5, 0xff, %g4
+	be		18f
+	 stb		%g4, [%o0 + 1]
+	srl		%o5, 8, %g5
+	andcc		%g5, 0xff, %g4
+	be		17f
+ 	 stb		%g4, [%o0 + 2]
+	andcc		%o5, 0xff, %g4
+	stb		%g4, [%o0 + 3]
+	bne		16b
+	 add		%o0, 4, %o0
+	retl
+	 sub		%o0, 1, %o0
+17:	retl
+	 add		%o0, 2, %o0
+18:	retl
+	 add		%o0, 1, %o0
+19:	retl
+	 nop
+END(__stpcpy)
+
+weak_alias(__stpcpy, stpcpy)