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-rw-r--r--sysdeps/powerpc/powerpc32/strcpy.S120
1 files changed, 120 insertions, 0 deletions
diff --git a/sysdeps/powerpc/powerpc32/strcpy.S b/sysdeps/powerpc/powerpc32/strcpy.S
new file mode 100644
index 0000000000..ed8eb7298e
--- /dev/null
+++ b/sysdeps/powerpc/powerpc32/strcpy.S
@@ -0,0 +1,120 @@
+/* Optimized strcpy implementation for PowerPC.
+   Copyright (C) 1997, 1999, 2000 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 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 <bp-sym.h>
+#include <bp-asm.h>
+
+/* See strlen.s for comments on how the end-of-string testing works.  */
+
+/* char * [r3] strcpy (char *dest [r3], const char *src [r4])  */
+
+EALIGN (BP_SYM (strcpy), 4, 0)
+
+#define rTMP	r0
+#define rRTN	r3	/* incoming DEST arg preserved as result */
+#if __BOUNDED_POINTERS__
+# define rDEST	r4	/* pointer to previous word in dest */
+# define rSRC	r5	/* pointer to previous word in src */
+# define rLOW	r11
+# define rHIGH	r12
+#else
+# define rSRC	r4	/* pointer to previous word in src */
+# define rDEST	r5	/* pointer to previous word in dest */
+#endif
+#define rWORD	r6	/* current word from src */
+#define rFEFE	r7	/* constant 0xfefefeff (-0x01010101) */
+#define r7F7F	r8	/* constant 0x7f7f7f7f */
+#define rNEG	r9	/* ~(word in s1 | 0x7f7f7f7f) */
+#define rALT	r10	/* alternate word from src */
+
+	CHECK_BOUNDS_LOW (rSRC, rLOW, rHIGH)
+	CHECK_BOUNDS_LOW (rDEST, rLOW, rHIGH)
+	STORE_RETURN_BOUNDS (rLOW, rHIGH)
+
+	or	rTMP, rSRC, rRTN
+	clrlwi.	rTMP, rTMP, 30
+#if __BOUNDED_POINTERS__
+	addi	rDEST, rDEST, -4
+#else
+	addi	rDEST, rRTN, -4
+#endif
+	bne	L(unaligned)
+
+	lis	rFEFE, -0x101
+	lis	r7F7F, 0x7f7f
+	lwz	rWORD, 0(rSRC)
+	addi	rFEFE, rFEFE, -0x101
+	addi	r7F7F, r7F7F, 0x7f7f
+	b	L(g2)
+
+L(g0):	lwzu	rALT, 4(rSRC)
+	stwu	rWORD, 4(rDEST)
+	add	rTMP, rFEFE, rALT
+	nor	rNEG, r7F7F, rALT
+	and.	rTMP, rTMP, rNEG
+	bne-	L(g1)
+	lwzu	rWORD, 4(rSRC)
+	stwu	rALT, 4(rDEST)
+L(g2):	add	rTMP, rFEFE, rWORD
+	nor	rNEG, r7F7F, rWORD
+	and.	rTMP, rTMP, rNEG
+	beq+	L(g0)
+
+	mr	rALT, rWORD
+/* We've hit the end of the string.  Do the rest byte-by-byte.  */
+L(g1):	rlwinm.	rTMP, rALT, 8, 24, 31
+	stb	rTMP, 4(rDEST)
+	beqlr-
+	rlwinm.	rTMP, rALT, 16, 24, 31
+	stb	rTMP, 5(rDEST)
+	beqlr-
+	rlwinm.	rTMP, rALT, 24, 24, 31
+	stb	rTMP, 6(rDEST)
+	beqlr-
+	stb	rALT, 7(rDEST)
+	/* GKM FIXME: check high bound.  */
+	blr
+
+/* Oh well.  In this case, we just do a byte-by-byte copy.  */
+	.align 4
+	nop
+L(unaligned):
+	lbz	rWORD, 0(rSRC)
+	addi	rDEST, rRTN, -1
+	cmpwi	rWORD, 0
+	beq-	L(u2)
+
+L(u0):	lbzu	rALT, 1(rSRC)
+	stbu	rWORD, 1(rDEST)
+	cmpwi	rALT, 0
+	beq-	L(u1)
+	nop		/* Let 601 load start of loop.  */
+	lbzu	rWORD, 1(rSRC)
+	stbu	rALT, 1(rDEST)
+	cmpwi	rWORD, 0
+	bne+	L(u0)
+L(u2):	stb	rWORD, 1(rDEST)
+	/* GKM FIXME: check high bound.  */
+	blr
+L(u1):	stb	rALT, 1(rDEST)
+	/* GKM FIXME: check high bound.  */
+	blr
+
+END (BP_SYM (strcpy))