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-rw-r--r--REORG.TODO/sysdeps/powerpc/powerpc64/power7/memmove.S835
1 files changed, 835 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/powerpc/powerpc64/power7/memmove.S b/REORG.TODO/sysdeps/powerpc/powerpc64/power7/memmove.S
new file mode 100644
index 0000000000..4c0f7c3571
--- /dev/null
+++ b/REORG.TODO/sysdeps/powerpc/powerpc64/power7/memmove.S
@@ -0,0 +1,835 @@
+/* Optimized memmove implementation for PowerPC64/POWER7.
+   Copyright (C) 2014-2017 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, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <sysdep.h>
+
+
+/* void* [r3] memmove (void *dest [r3], const void *src [r4], size_t len [r5])
+
+   This optimization check if memory 'dest'  overlaps with 'src'. If it does
+   not then it calls an optimized memcpy call (similar to memcpy for POWER7,
+   embedded here to gain some cycles).
+   If source and destiny overlaps, a optimized backwards memcpy is used
+   instead.  */
+
+#ifndef MEMMOVE
+# define MEMMOVE memmove
+#endif
+	.machine power7
+EALIGN (MEMMOVE, 5, 0)
+	CALL_MCOUNT 3
+
+L(_memmove):
+	subf    r9,r4,r3
+	cmpld   cr7,r9,r5
+	blt	cr7,L(memmove_bwd)
+
+	cmpldi	cr1,r5,31
+	neg	0,3
+	ble	cr1, L(copy_LT_32)  /* If move < 32 bytes use short move
+				       code.  */
+
+	andi.	10,3,15
+	clrldi	11,4,60
+	cmpld	cr6,10,11	/* SRC and DST alignments match?  */
+
+	mr	r11,3
+	bne	cr6,L(copy_GE_32_unaligned)
+	beq	L(aligned_copy)
+
+	mtocrf	0x01,0
+	clrldi	0,0,60
+
+/* Get the DST and SRC aligned to 8 bytes (16 for little-endian).  */
+1:
+	bf	31,2f
+	lbz	6,0(r4)
+	addi	r4,r4,1
+	stb	6,0(r11)
+	addi	r11,r11,1
+2:
+	bf	30,4f
+	lhz	6,0(r4)
+	addi	r4,r4,2
+	sth	6,0(r11)
+	addi	r11,r11,2
+4:
+	bf	29,8f
+	lwz	6,0(r4)
+	addi	r4,r4,4
+	stw	6,0(r11)
+	addi	r11,r11,4
+8:
+	bf	28,16f
+	ld	6,0(r4)
+	addi	r4,r4,8
+	std	6,0(r11)
+	addi	r11,r11,8
+16:
+	subf	r5,0,r5
+
+/* Main aligned copy loop. Copies 128 bytes at a time. */
+L(aligned_copy):
+	li	6,16
+	li	7,32
+	li	8,48
+	mtocrf	0x02,r5
+	srdi	12,r5,7
+	cmpdi	12,0
+	beq	L(aligned_tail)
+	lxvd2x	6,0,r4
+	lxvd2x	7,r4,6
+	mtctr	12
+	b	L(aligned_128loop)
+
+	.align  4
+L(aligned_128head):
+	/* for the 2nd + iteration of this loop. */
+	lxvd2x	6,0,r4
+	lxvd2x	7,r4,6
+L(aligned_128loop):
+	lxvd2x	8,r4,7
+	lxvd2x	9,r4,8
+	stxvd2x	6,0,r11
+	addi	r4,r4,64
+	stxvd2x	7,r11,6
+	stxvd2x	8,r11,7
+	stxvd2x	9,r11,8
+	lxvd2x	6,0,r4
+	lxvd2x	7,r4,6
+	addi	r11,r11,64
+	lxvd2x	8,r4,7
+	lxvd2x	9,r4,8
+	addi	r4,r4,64
+	stxvd2x	6,0,r11
+	stxvd2x	7,r11,6
+	stxvd2x	8,r11,7
+	stxvd2x	9,r11,8
+	addi	r11,r11,64
+	bdnz	L(aligned_128head)
+
+L(aligned_tail):
+	mtocrf	0x01,r5
+	bf	25,32f
+	lxvd2x	6,0,r4
+	lxvd2x	7,r4,6
+	lxvd2x	8,r4,7
+	lxvd2x	9,r4,8
+	addi	r4,r4,64
+	stxvd2x	6,0,r11
+	stxvd2x	7,r11,6
+	stxvd2x	8,r11,7
+	stxvd2x	9,r11,8
+	addi	r11,r11,64
+32:
+	bf	26,16f
+	lxvd2x	6,0,r4
+	lxvd2x	7,r4,6
+	addi	r4,r4,32
+	stxvd2x	6,0,r11
+	stxvd2x	7,r11,6
+	addi	r11,r11,32
+16:
+	bf	27,8f
+	lxvd2x	6,0,r4
+	addi	r4,r4,16
+	stxvd2x	6,0,r11
+	addi	r11,r11,16
+8:
+	bf	28,4f
+	ld	6,0(r4)
+	addi	r4,r4,8
+	std     6,0(r11)
+	addi	r11,r11,8
+4:	/* Copies 4~7 bytes.  */
+	bf	29,L(tail2)
+	lwz	6,0(r4)
+	stw     6,0(r11)
+	bf      30,L(tail5)
+	lhz     7,4(r4)
+	sth     7,4(r11)
+	bflr	31
+	lbz     8,6(r4)
+	stb     8,6(r11)
+	/* Return original DST pointer.  */
+	blr
+
+/* Handle copies of 0~31 bytes.  */
+	.align	4
+L(copy_LT_32):
+	mr	r11,3
+	cmpldi	cr6,r5,8
+	mtocrf	0x01,r5
+	ble	cr6,L(copy_LE_8)
+
+	/* At least 9 bytes to go.  */
+	neg	8,4
+	andi.	0,8,3
+	cmpldi	cr1,r5,16
+	beq	L(copy_LT_32_aligned)
+
+	/* Force 4-byte alignment for SRC.  */
+	mtocrf	0x01,0
+	subf	r5,0,r5
+2:
+	bf	30,1f
+	lhz	6,0(r4)
+	addi	r4,r4,2
+	sth	6,0(r11)
+	addi	r11,r11,2
+1:
+	bf	31,L(end_4bytes_alignment)
+	lbz	6,0(r4)
+	addi	r4,r4,1
+	stb	6,0(r11)
+	addi	r11,r11,1
+
+	.align	4
+L(end_4bytes_alignment):
+	cmpldi	cr1,r5,16
+	mtocrf	0x01,r5
+
+L(copy_LT_32_aligned):
+	/* At least 6 bytes to go, and SRC is word-aligned.  */
+	blt	cr1,8f
+
+	/* Copy 16 bytes.  */
+	lwz	6,0(r4)
+	lwz	7,4(r4)
+	stw	6,0(r11)
+	lwz	8,8(r4)
+	stw	7,4(r11)
+	lwz	6,12(r4)
+	addi	r4,r4,16
+	stw	8,8(r11)
+	stw	6,12(r11)
+	addi	r11,r11,16
+8:	/* Copy 8 bytes.  */
+	bf	28,L(tail4)
+	lwz	6,0(r4)
+	lwz	7,4(r4)
+	addi	r4,r4,8
+	stw	6,0(r11)
+	stw	7,4(r11)
+	addi	r11,r11,8
+
+	.align	4
+/* Copies 4~7 bytes.  */
+L(tail4):
+	bf	29,L(tail2)
+	lwz	6,0(r4)
+	stw	6,0(r11)
+	bf	30,L(tail5)
+	lhz	7,4(r4)
+	sth	7,4(r11)
+	bflr	31
+	lbz	8,6(r4)
+	stb	8,6(r11)
+	/* Return original DST pointer.  */
+	blr
+
+	.align	4
+/* Copies 2~3 bytes.  */
+L(tail2):
+	bf	30,1f
+	lhz	6,0(r4)
+	sth	6,0(r11)
+	bflr	31
+	lbz	7,2(r4)
+	stb	7,2(r11)
+	blr
+
+	.align	4
+L(tail5):
+	bflr	31
+	lbz	6,4(r4)
+	stb	6,4(r11)
+	blr
+
+	.align	4
+1:
+	bflr	31
+	lbz	6,0(r4)
+	stb	6,0(r11)
+	/* Return original DST pointer.  */
+	blr
+
+/* Handles copies of 0~8 bytes.  */
+	.align	4
+L(copy_LE_8):
+	bne	cr6,L(tail4)
+
+	/* Though we could've used ld/std here, they are still
+	slow for unaligned cases.  */
+
+	lwz	6,0(r4)
+	lwz	7,4(r4)
+	stw	6,0(r11)
+	stw	7,4(r11)
+	blr
+
+
+/* Handle copies of 32+ bytes where DST is aligned (to quadword) but
+   SRC is not.	Use aligned quadword loads from SRC, shifted to realign
+   the data, allowing for aligned DST stores.  */
+	.align	4
+L(copy_GE_32_unaligned):
+	clrldi	0,0,60	      /* Number of bytes until the 1st r11 quadword.  */
+	srdi	9,r5,4	      /* Number of full quadwords remaining.  */
+
+	beq	L(copy_GE_32_unaligned_cont)
+
+	/* DST is not quadword aligned, get it aligned.  */
+
+	mtocrf	0x01,0
+	subf	r5,0,r5
+
+	/* Vector instructions work best when proper alignment (16-bytes)
+	is present.  Move 0~15 bytes as needed to get DST quadword-aligned.  */
+1:
+	bf	31,2f
+	lbz	6,0(r4)
+	addi	r4,r4,1
+	stb	6,0(r11)
+	addi	r11,r11,1
+2:
+	bf	30,4f
+	lhz	6,0(r4)
+	addi	r4,r4,2
+	sth	6,0(r11)
+	addi	r11,r11,2
+4:
+	bf	29,8f
+	lwz	6,0(r4)
+	addi	r4,r4,4
+	stw	6,0(r11)
+	addi	r11,r11,4
+8:
+	bf	28,0f
+	ld	6,0(r4)
+	addi	r4,r4,8
+	std	6,0(r11)
+	addi	r11,r11,8
+0:
+	srdi	9,r5,4	      /* Number of full quadwords remaining.  */
+
+	/* The proper alignment is present, it is OK to copy the bytes now.  */
+L(copy_GE_32_unaligned_cont):
+
+	/* Setup two indexes to speed up the indexed vector operations.  */
+	clrldi	10,r5,60
+	li	6,16	      /* Index for 16-bytes offsets.  */
+	li	7,32	      /* Index for 32-bytes offsets.  */
+	cmpldi	cr1,10,0
+	srdi	8,r5,5	      /* Setup the loop counter.  */
+	mtocrf	0x01,9
+	cmpldi	cr6,9,1
+#ifdef __LITTLE_ENDIAN__
+	lvsr	5,0,r4
+#else
+	lvsl	5,0,r4
+#endif
+	lvx	3,0,r4
+	li	0,0
+	bf	31,L(setup_unaligned_loop)
+
+	/* Copy another 16 bytes to align to 32-bytes due to the loop.  */
+	lvx	4,r4,6
+#ifdef __LITTLE_ENDIAN__
+	vperm	6,4,3,5
+#else
+	vperm	6,3,4,5
+#endif
+	addi	r4,r4,16
+	stvx	6,0,r11
+	addi	r11,r11,16
+	vor	3,4,4
+	clrrdi	0,r4,60
+
+L(setup_unaligned_loop):
+	mtctr	8
+	ble	cr6,L(end_unaligned_loop)
+
+	/* Copy 32 bytes at a time using vector instructions.  */
+	.align	4
+L(unaligned_loop):
+
+	/* Note: vr6/vr10 may contain data that was already copied,
+	but in order to get proper alignment, we may have to copy
+	some portions again. This is faster than having unaligned
+	vector instructions though.  */
+
+	lvx	4,r4,6
+#ifdef __LITTLE_ENDIAN__
+	vperm	6,4,3,5
+#else
+	vperm	6,3,4,5
+#endif
+	lvx	3,r4,7
+#ifdef __LITTLE_ENDIAN__
+	vperm	10,3,4,5
+#else
+	vperm	10,4,3,5
+#endif
+	addi	r4,r4,32
+	stvx	6,0,r11
+	stvx	10,r11,6
+	addi	r11,r11,32
+	bdnz	L(unaligned_loop)
+
+	clrrdi	0,r4,60
+
+	.align	4
+L(end_unaligned_loop):
+
+	/* Check for tail bytes.  */
+	mtocrf	0x01,r5
+	beqlr	cr1
+
+	add	r4,r4,0
+
+	/*  We have 1~15 tail bytes to copy, and DST is quadword aligned.  */
+	/* Copy 8 bytes.  */
+	bf	28,4f
+	lwz	6,0(r4)
+	lwz	7,4(r4)
+	addi	r4,r4,8
+	stw	6,0(r11)
+	stw	7,4(r11)
+	addi	r11,r11,8
+4:	/* Copy 4~7 bytes.  */
+	bf	29,L(tail2)
+	lwz	6,0(r4)
+	stw	6,0(r11)
+	bf	30,L(tail5)
+	lhz	7,4(r4)
+	sth	7,4(r11)
+	bflr	31
+	lbz	8,6(r4)
+	stb	8,6(r11)
+	/* Return original DST pointer.  */
+	blr
+
+	/* Start to memcpy backward implementation: the algorith first check if
+	   src and dest have the same alignment and if it does align both to 16
+	   bytes and copy using VSX instructions.
+	   If does not, align dest to 16 bytes and use VMX (altivec) instruction
+	   to read two 16 bytes at time, shift/permute the bytes read and write
+	   aligned to dest.  */
+L(memmove_bwd):
+	cmpldi	cr1,r5,31
+	/* Copy is done backwards: update the pointers and check alignment.  */
+	add	r11,r3,r5
+	add	r4,r4,r5
+	mr	r0,r11
+	ble	cr1, L(copy_LT_32_bwd)  /* If move < 32 bytes use short move
+				           code.  */
+
+	andi.	r10,r11,15	    /* Check if r11 is aligned to 16 bytes  */
+	clrldi	r9,r4,60	    /* Check if r4 is aligned to 16 bytes  */
+	cmpld	cr6,r10,r9	    /* SRC and DST alignments match?  */
+
+	bne     cr6,L(copy_GE_32_unaligned_bwd)
+	beq     L(aligned_copy_bwd)
+
+	mtocrf	0x01,r0
+	clrldi	r0,r0,60
+
+/* Get the DST and SRC aligned to 16 bytes.  */
+1:
+	bf	31,2f
+	lbz	r6,-1(r4)
+	subi	r4,r4,1
+	stb	r6,-1(r11)
+	subi	r11,r11,1
+2:
+	bf	30,4f
+	lhz	r6,-2(r4)
+	subi	r4,r4,2
+	sth	r6,-2(r11)
+	subi	r11,r11,2
+4:
+	bf	29,8f
+	lwz	r6,-4(r4)
+	subi	r4,r4,4
+	stw	r6,-4(r11)
+	subi	r11,r11,4
+8:
+	bf	28,16f
+	ld	r6,-8(r4)
+	subi	r4,r4,8
+	std	r6,-8(r11)
+	subi	r11,r11,8
+16:
+	subf	r5,0,r5
+
+/* Main aligned copy loop. Copies 128 bytes at a time. */
+L(aligned_copy_bwd):
+	li	r6,-16
+	li	r7,-32
+	li	r8,-48
+	li	r9,-64
+	mtocrf	0x02,r5
+	srdi	r12,r5,7
+	cmpdi	r12,0
+	beq	L(aligned_tail_bwd)
+	lxvd2x	v6,r4,r6
+	lxvd2x	v7,r4,r7
+	mtctr	12
+	b	L(aligned_128loop_bwd)
+
+	.align  4
+L(aligned_128head_bwd):
+	/* for the 2nd + iteration of this loop. */
+	lxvd2x	v6,r4,r6
+	lxvd2x	v7,r4,r7
+L(aligned_128loop_bwd):
+	lxvd2x	v8,r4,r8
+	lxvd2x	v9,r4,r9
+	stxvd2x	v6,r11,r6
+	subi	r4,r4,64
+	stxvd2x	v7,r11,r7
+	stxvd2x	v8,r11,r8
+	stxvd2x	v9,r11,r9
+	lxvd2x	v6,r4,r6
+	lxvd2x	v7,r4,7
+	subi	r11,r11,64
+	lxvd2x	v8,r4,r8
+	lxvd2x	v9,r4,r9
+	subi	r4,r4,64
+	stxvd2x	v6,r11,r6
+	stxvd2x	v7,r11,r7
+	stxvd2x	v8,r11,r8
+	stxvd2x	v9,r11,r9
+	subi	r11,r11,64
+	bdnz	L(aligned_128head_bwd)
+
+L(aligned_tail_bwd):
+	mtocrf	0x01,r5
+	bf	25,32f
+	lxvd2x	v6,r4,r6
+	lxvd2x	v7,r4,r7
+	lxvd2x	v8,r4,r8
+	lxvd2x	v9,r4,r9
+	subi	r4,r4,64
+	stxvd2x	v6,r11,r6
+	stxvd2x	v7,r11,r7
+	stxvd2x	v8,r11,r8
+	stxvd2x	v9,r11,r9
+	subi	r11,r11,64
+32:
+	bf	26,16f
+	lxvd2x	v6,r4,r6
+	lxvd2x	v7,r4,r7
+	subi	r4,r4,32
+	stxvd2x	v6,r11,r6
+	stxvd2x	v7,r11,r7
+	subi	r11,r11,32
+16:
+	bf	27,8f
+	lxvd2x	v6,r4,r6
+	subi	r4,r4,16
+	stxvd2x	v6,r11,r6
+	subi	r11,r11,16
+8:
+	bf	28,4f
+	ld	r6,-8(r4)
+	subi	r4,r4,8
+	std     r6,-8(r11)
+	subi	r11,r11,8
+4:	/* Copies 4~7 bytes.  */
+	bf	29,L(tail2_bwd)
+	lwz	r6,-4(r4)
+	stw     r6,-4(r11)
+	bf      30,L(tail5_bwd)
+	lhz     r7,-6(r4)
+	sth     r7,-6(r11)
+	bflr	31
+	lbz     r8,-7(r4)
+	stb     r8,-7(r11)
+	/* Return original DST pointer.  */
+	blr
+
+/* Handle copies of 0~31 bytes.  */
+	.align	4
+L(copy_LT_32_bwd):
+	cmpldi	cr6,r5,8
+	mtocrf	0x01,r5
+	ble	cr6,L(copy_LE_8_bwd)
+
+	/* At least 9 bytes to go.  */
+	neg	r8,r4
+	andi.	r0,r8,3
+	cmpldi	cr1,r5,16
+	beq	L(copy_LT_32_aligned_bwd)
+
+	/* Force 4-byte alignment for SRC.  */
+	mtocrf	0x01,0
+	subf	r5,0,r5
+2:
+	bf	30,1f
+	lhz	r6,-2(r4)
+	subi	r4,r4,2
+	sth	r6,-2(r11)
+	subi	r11,r11,2
+1:
+	bf	31,L(end_4bytes_alignment_bwd)
+	lbz	6,-1(r4)
+	subi	r4,r4,1
+	stb	6,-1(r11)
+	subi	r11,r11,1
+
+	.align	4
+L(end_4bytes_alignment_bwd):
+	cmpldi	cr1,r5,16
+	mtocrf	0x01,r5
+
+L(copy_LT_32_aligned_bwd):
+	/* At least 6 bytes to go, and SRC is word-aligned.  */
+	blt	cr1,8f
+
+	/* Copy 16 bytes.  */
+	lwz	r6,-4(r4)
+	lwz	r7,-8(r4)
+	stw	r6,-4(r11)
+	lwz	r8,-12(r4)
+	stw	r7,-8(r11)
+	lwz	r6,-16(r4)
+	subi	r4,r4,16
+	stw	r8,-12(r11)
+	stw	r6,-16(r11)
+	subi	r11,r11,16
+8:	/* Copy 8 bytes.  */
+	bf	28,L(tail4_bwd)
+	lwz	r6,-4(r4)
+	lwz	r7,-8(r4)
+	subi	r4,r4,8
+	stw	r6,-4(r11)
+	stw	r7,-8(r11)
+	subi	r11,r11,8
+
+	.align	4
+/* Copies 4~7 bytes.  */
+L(tail4_bwd):
+	bf	29,L(tail2_bwd)
+	lwz	6,-4(r4)
+	stw	6,-4(r11)
+	bf	30,L(tail5_bwd)
+	lhz	7,-6(r4)
+	sth	7,-6(r11)
+	bflr	31
+	lbz	8,-7(r4)
+	stb	8,-7(r11)
+	/* Return original DST pointer.  */
+	blr
+
+	.align	4
+/* Copies 2~3 bytes.  */
+L(tail2_bwd):
+	bf	30,1f
+	lhz	6,-2(r4)
+	sth	6,-2(r11)
+	bflr	31
+	lbz	7,-3(r4)
+	stb	7,-3(r11)
+	blr
+
+	.align	4
+L(tail5_bwd):
+	bflr	31
+	lbz	6,-5(r4)
+	stb	6,-5(r11)
+	blr
+
+	.align	4
+1:
+	bflr	31
+	lbz	6,-1(r4)
+	stb	6,-1(r11)
+	/* Return original DST pointer.  */
+	blr
+
+
+/* Handles copies of 0~8 bytes.  */
+	.align	4
+L(copy_LE_8_bwd):
+	bne	cr6,L(tail4_bwd)
+
+	/* Though we could've used ld/std here, they are still
+	   slow for unaligned cases.  */
+	lwz	6,-8(r4)
+	lwz	7,-4(r4)
+	stw	6,-8(r11)
+	stw	7,-4(r11)
+	blr
+
+
+/* Handle copies of 32+ bytes where DST is aligned (to quadword) but
+   SRC is not.	Use aligned quadword loads from SRC, shifted to realign
+   the data, allowing for aligned DST stores.  */
+	.align	4
+L(copy_GE_32_unaligned_bwd):
+	andi.	r10,r11,15      /* Check alignment of DST against 16 bytes..  */
+	srdi	r9,r5,4		/* Number of full quadwords remaining.  */
+
+	beq	L(copy_GE_32_unaligned_cont_bwd)
+
+	/* DST is not quadword aligned and r10 holds the address masked to
+           compare alignments.  */
+	mtocrf	0x01,r10
+	subf	r5,r10,r5
+
+	/* Vector instructions work best when proper alignment (16-bytes)
+	is present.  Move 0~15 bytes as needed to get DST quadword-aligned.  */
+1:
+	bf	31,2f
+	lbz	r6,-1(r4)
+	subi	r4,r4,1
+	stb	r6,-1(r11)
+	subi	r11,r11,1
+2:
+	bf	30,4f
+	lhz	r6,-2(r4)
+	subi	r4,r4,2
+	sth	r6,-2(r11)
+	subi	r11,r11,2
+4:
+	bf	29,8f
+	lwz	r6,-4(r4)
+	subi	r4,r4,4
+	stw	r6,-4(r11)
+	subi	r11,r11,4
+8:
+	bf	28,0f
+	ld	r6,-8(r4)
+	subi	r4,r4,8
+	std	r6,-8(r11)
+	subi	r11,r11,8
+0:
+	srdi	r9,r5,4	      /* Number of full quadwords remaining.  */
+
+	/* The proper alignment is present, it is OK to copy the bytes now.  */
+L(copy_GE_32_unaligned_cont_bwd):
+
+	/* Setup two indexes to speed up the indexed vector operations.  */
+	clrldi	r10,r5,60
+	li	r6,-16	      /* Index for 16-bytes offsets.  */
+	li	r7,-32	      /* Index for 32-bytes offsets.  */
+	cmpldi	cr1,10,0
+	srdi	r8,r5,5	      /* Setup the loop counter.  */
+	mtocrf	0x01,9
+	cmpldi	cr6,r9,1
+#ifdef __LITTLE_ENDIAN__
+	lvsr	v5,r0,r4
+#else
+	lvsl	v5,r0,r4
+#endif
+	lvx	v3,0,r4
+	li	r0,0
+	bf	31,L(setup_unaligned_loop_bwd)
+
+	/* Copy another 16 bytes to align to 32-bytes due to the loop.  */
+	lvx	v4,r4,r6
+#ifdef __LITTLE_ENDIAN__
+	vperm	v6,v3,v4,v5
+#else
+	vperm	v6,v4,v3,v5
+#endif
+	subi	r4,r4,16
+	stvx	v6,r11,r6
+	subi	r11,r11,16
+	vor	v3,v4,v4
+	clrrdi	r0,r4,60
+
+L(setup_unaligned_loop_bwd):
+	mtctr	r8
+	ble	cr6,L(end_unaligned_loop_bwd)
+
+	/* Copy 32 bytes at a time using vector instructions.  */
+	.align	4
+L(unaligned_loop_bwd):
+
+	/* Note: vr6/vr10 may contain data that was already copied,
+	but in order to get proper alignment, we may have to copy
+	some portions again. This is faster than having unaligned
+	vector instructions though.  */
+
+	lvx	v4,r4,r6
+#ifdef __LITTLE_ENDIAN__
+	vperm	v6,v3,v4,v5
+#else
+	vperm	v6,v4,v3,v5
+#endif
+	lvx	v3,r4,r7
+#ifdef __LITTLE_ENDIAN__
+	vperm	v10,v4,v3,v5
+#else
+	vperm	v10,v3,v4,v5
+#endif
+	subi	r4,r4,32
+	stvx	v6,r11,r6
+	stvx	v10,r11,r7
+	subi	r11,r11,32
+	bdnz	L(unaligned_loop_bwd)
+
+	clrrdi	r0,r4,60
+
+	.align	4
+L(end_unaligned_loop_bwd):
+
+	/* Check for tail bytes.  */
+	mtocrf	0x01,r5
+	beqlr	cr1
+
+	add	r4,r4,0
+
+	/*  We have 1~15 tail bytes to copy, and DST is quadword aligned.  */
+	/* Copy 8 bytes.  */
+	bf	28,4f
+	lwz	r6,-4(r4)
+	lwz	r7,-8(r4)
+	subi	r4,r4,8
+	stw	r6,-4(r11)
+	stw	r7,-8(r11)
+	subi	r11,r11,8
+4:	/* Copy 4~7 bytes.  */
+	bf	29,L(tail2_bwd)
+	lwz	r6,-4(r4)
+	stw	r6,-4(r11)
+	bf	30,L(tail5_bwd)
+	lhz	r7,-6(r4)
+	sth	r7,-6(r11)
+	bflr	31
+	lbz	r8,-7(r4)
+	stb	r8,-7(r11)
+	/* Return original DST pointer.  */
+	blr
+END_GEN_TB (MEMMOVE, TB_TOCLESS)
+libc_hidden_builtin_def (memmove)
+
+
+/* void bcopy(const void *src [r3], void *dest [r4], size_t n [r5])
+   Implemented in this file to avoid linker create a stub function call
+   in the branch to '_memmove'.  */
+ENTRY (__bcopy)
+	mr	r6,r3
+	mr	r3,r4
+	mr	r4,r6
+	b	L(_memmove)
+END (__bcopy)
+weak_alias (__bcopy, bcopy)