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-rw-r--r--sysdeps/powerpc/strcpy.S100
1 files changed, 100 insertions, 0 deletions
diff --git a/sysdeps/powerpc/strcpy.S b/sysdeps/powerpc/strcpy.S
new file mode 100644
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+++ b/sysdeps/powerpc/strcpy.S
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+/* Optimized strcpy 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(strcpy,4,0)
+/* char * [r3] strcpy (char *dest [r3], const char *src [r4]) */
+
+/* General register assignments:
+ r0: temporary
+ r3: saved `dest'
+ r4: pointer to previous word in src
+ r5: pointer to previous word in dest
+ r6: current word from src
+ r7: 0xfefefeff
+ r8: 0x7f7f7f7f
+ r9: ~(word in src | 0x7f7f7f7f)
+ r10: alternate word from src. */
+
+ or %r0,%r4,%r3
+ clrlwi. %r0,%r0,30
+ addi %r5,%r3,-4
+ bne L(unaligned)
+
+ lis %r7,0xfeff
+ lis %r8,0x7f7f
+ lwz %r6,0(%r4)
+ addi %r7,%r7,-0x101
+ addi %r8,%r8,0x7f7f
+ b 2f
+
+0: lwzu %r10,4(%r4)
+ stwu %r6,4(%r5)
+ add %r0,%r7,%r10
+ nor %r9,%r8,%r10
+ and. %r0,%r0,%r9
+ bne- 1f
+ lwzu %r6,4(%r4)
+ stwu %r10,4(%r5)
+2: add %r0,%r7,%r6
+ nor %r9,%r8,%r6
+ and. %r0,%r0,%r9
+ beq+ 0b
+
+ mr %r10,%r6
+/* We've hit the end of the string. Do the rest byte-by-byte. */
+1: rlwinm. %r0,%r10,8,24,31
+ stb %r0,4(%r5)
+ beqlr-
+ rlwinm. %r0,%r10,16,24,31
+ stb %r0,5(%r5)
+ beqlr-
+ rlwinm. %r0,%r10,24,24,31
+ stb %r0,6(%r5)
+ beqlr-
+ stb %r10,7(%r5)
+ blr
+
+/* Oh well. In this case, we just do a byte-by-byte copy. */
+ .align 4
+ nop
+L(unaligned):
+ lbz %r6,0(%r4)
+ addi %r5,%r3,-1
+ cmpwi %r6,0
+ beq- 2f
+
+0: lbzu %r10,1(%r4)
+ stbu %r6,1(%r5)
+ cmpwi %r10,0
+ beq- 1f
+ nop /* Let 601 load start of loop. */
+ lbzu %r6,1(%r4)
+ stbu %r10,1(%r5)
+ cmpwi %r6,0
+ bne+ 0b
+2: stb %r6,1(%r5)
+ blr
+1: stb %r10,1(%r5)
+ blr
+
+END(strcpy)