1 files changed, 115 insertions, 0 deletions
diff --git a/sysdeps/powerpc/strcmp.S b/sysdeps/powerpc/strcmp.S
new file mode 100644
index 0000000..9f4d134
--- /dev/null
+++ b/sysdeps/powerpc/strcmp.S
@@ -0,0 +1,115 @@
+/* Optimized strcmp implementation for PowerPC.
+   Copyright (C) 1997 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 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>
+
+/* See strlen.s for comments on how the end-of-string testing works.  */
+
+EALIGN(strcmp,4,0)
+/* int [r3] strcmp (const char *p1 [r3], const char *p2 [r4])  */
+
+/* General register assignments:
+   r0:	temporary
+   r3:	pointer to previous word in s1
+   r4:	pointer to previous word in s2
+   r5:	current word from s1
+   r6:	current word from s2
+   r7:	0xfefefeff
+   r8:	0x7f7f7f7f
+   r9:	~(word in s1 | 0x7f7f7f7f)  */
+
+/* Register assignments in the prologue:
+   r10:	low 2 bits of p2-p1
+   r11:	mask to orc with r5/r6  */
+
+	or    %r0,%r4,%r3
+	clrlwi. %r0,%r0,30
+	lis   %r7,0xfeff
+	bne   L(unaligned)
+
+	lwz   %r5,0(%r3)
+	lwz   %r6,0(%r4)
+	lis   %r8,0x7f7f
+	addi  %r7,%r7,-0x101
+	addi  %r8,%r8,0x7f7f
+	b     1f
+
+0:	lwzu  %r5,4(%r3)
+	bne   %cr1,L(different)
+	lwzu  %r6,4(%r4)
+1:	add   %r0,%r7,%r5
+	nor   %r9,%r8,%r5
+	and.  %r0,%r0,%r9
+	cmpw  %cr1,%r5,%r6
+	beq+  0b
+L(endstring):
+/* OK. We've hit the end of the string. We need to be careful that
+   we don't compare two strings as different because of gunk beyond
+   the end of the strings...  */
+	and   %r0,%r8,%r5
+	beq   %cr1,L(equal)
+	add   %r0,%r0,%r8
+	xor.  %r10,%r5,%r6
+	andc  %r9,%r9,%r0
+	blt-  L(highbit)
+	cntlzw %r10,%r10
+	cntlzw %r9,%r9
+	addi  %r9,%r9,7
+	cmpw  %cr1,%r9,%r10
+	sub   %r3,%r5,%r6
+	bgelr+ %cr1
+L(equal):
+	li    %r3,0
+	blr
+
+L(different):
+	lwz   %r5,-4(%r3)
+	xor.  %r10,%r5,%r6
+	sub   %r3,%r5,%r6
+	bgelr+
+L(highbit):
+	mr    %r3,%r6
+	blr
+
+
+/* Oh well.  In this case, we just do a byte-by-byte comparison.  */
+	.align 4
+L(unaligned):
+	lbz   %r5,0(%r3)
+	lbz   %r6,0(%r4)
+	b     1f
+
+0:	lbzu  %r5,1(%r3)
+	bne-  4f
+	lbzu  %r6,1(%r4)
+1:	cmpwi %cr1,%r5,0
+	beq-  %cr1,3f
+	cmpw  %r5,%r6
+	bne-  3f
+	lbzu  %r5,1(%r3)
+	lbzu  %r6,1(%r4)
+	cmpwi %cr1,%r5,0
+	cmpw  %r5,%r6
+	bne+  %cr1,0b
+3:	sub   %r3,%r5,%r6
+	blr
+4:	lbz   %r5,-1(%r3)
+	sub   %r3,%r5,%r6
+	blr
+END(strcmp)