/* Optimized memcpy implementation for PowerPC64/POWER7.
Copyright (C) 2010-2018 Free Software Foundation, Inc.
Contributed by Luis Machado <luisgpm@br.ibm.com>.
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] memcpy (void *dst [r3], void *src [r4], size_t len [r5]);
Returns 'dst'. */
#ifndef MEMCPY
# define MEMCPY memcpy
#endif
#define dst 11 /* Use r11 so r3 kept unchanged. */
#define src 4
#define cnt 5
.machine power7
ENTRY_TOCLESS (MEMCPY, 5)
CALL_MCOUNT 3
cmpldi cr1,cnt,31
neg 0,3
ble cr1, L(copy_LT_32) /* If move < 32 bytes use short move
code. */
/* Align copies using VSX instructions to quadword. It is to avoid alignment
traps when memcpy is used on non-cacheable memory (for instance, memory
mapped I/O). */
andi. 10,3,15
clrldi 11,4,60
cmpld cr6,10,11 /* SRC and DST alignments match? */
mr dst,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 16 bytes. */
1:
bf 31,2f
lbz 6,0(src)
addi src,src,1
stb 6,0(dst)
addi dst,dst,1
2:
bf 30,4f
lhz 6,0(src)
addi src,src,2
sth 6,0(dst)
addi dst,dst,2
4:
bf 29,8f
lwz 6,0(src)
addi src,src,4
stw 6,0(dst)
addi dst,dst,4
8:
bf 28,16f
ld 6,0(src)
addi src,src,8
std 6,0(dst)
addi dst,dst,8
16:
subf cnt,0,cnt
/* Main aligned copy loop. Copies 128 bytes at a time. */
L(aligned_copy):
li 6,16
li 7,32
li 8,48
mtocrf 0x02,cnt
srdi 12,cnt,7
cmpdi 12,0
beq L(aligned_tail)
lvx 6,0,src
lvx 7,src,6
mtctr 12
b L(aligned_128loop)
.align 4
L(aligned_128head):
/* for the 2nd + iteration of this loop. */
lvx 6,0,src
lvx 7,src,6
L(aligned_128loop):
lvx 8,src,7
lvx 9,src,8
stvx 6,0,dst
addi src,src,64
stvx 7,dst,6
stvx 8,dst,7
stvx 9,dst,8
lvx 6,0,src
lvx 7,src,6
addi dst,dst,64
lvx 8,src,7
lvx 9,src,8
addi src,src,64
stvx 6,0,dst
stvx 7,dst,6
stvx 8,dst,7
stvx 9,dst,8
addi dst,dst,64
bdnz L(aligned_128head)
L(aligned_tail):
mtocrf 0x01,cnt
bf 25,32f
lvx 6,0,src
lvx 7,src,6
lvx 8,src,7
lvx 9,src,8
addi src,src,64
stvx 6,0,dst
stvx 7,dst,6
stvx 8,dst,7
stvx 9,dst,8
addi dst,dst,64
32:
bf 26,16f
lvx 6,0,src
lvx 7,src,6
addi src,src,32
stvx 6,0,dst
stvx 7,dst,6
addi dst,dst,32
16:
bf 27,8f
lvx 6,0,src
addi src,src,16
stvx 6,0,dst
addi dst,dst,16
8:
bf 28,4f
ld 6,0(src)
addi src,src,8
std 6,0(dst)
addi dst,dst,8
4: /* Copies 4~7 bytes. */
bf 29,L(tail2)
lwz 6,0(src)
stw 6,0(dst)
bf 30,L(tail5)
lhz 7,4(src)
sth 7,4(dst)
bflr 31
lbz 8,6(src)
stb 8,6(dst)
/* Return original DST pointer. */
blr
/* Handle copies of 0~31 bytes. */
.align 4
L(copy_LT_32):
mr dst,3
cmpldi cr6,cnt,8
mtocrf 0x01,cnt
ble cr6,L(copy_LE_8)
/* At least 9 bytes to go. */
neg 8,4
andi. 0,8,3
cmpldi cr1,cnt,16
beq L(copy_LT_32_aligned)
/* Force 4-byte alignment for SRC. */
mtocrf 0x01,0
subf cnt,0,cnt
2:
bf 30,1f
lhz 6,0(src)
addi src,src,2
sth 6,0(dst)
addi dst,dst,2
1:
bf 31,L(end_4bytes_alignment)
lbz 6,0(src)
addi src,src,1
stb 6,0(dst)
addi dst,dst,1
.align 4
L(end_4bytes_alignment):
cmpldi cr1,cnt,16
mtocrf 0x01,cnt
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(src)
lwz 7,4(src)
stw 6,0(dst)
lwz 8,8(src)
stw 7,4(dst)
lwz 6,12(src)
addi src,src,16
stw 8,8(dst)
stw 6,12(dst)
addi dst,dst,16
8: /* Copy 8 bytes. */
bf 28,L(tail4)
lwz 6,0(src)
lwz 7,4(src)
addi src,src,8
stw 6,0(dst)
stw 7,4(dst)
addi dst,dst,8
.align 4
/* Copies 4~7 bytes. */
L(tail4):
bf 29,L(tail2)
lwz 6,0(src)
stw 6,0(dst)
bf 30,L(tail5)
lhz 7,4(src)
sth 7,4(dst)
bflr 31
lbz 8,6(src)
stb 8,6(dst)
/* Return original DST pointer. */
blr
.align 4
/* Copies 2~3 bytes. */
L(tail2):
bf 30,1f
lhz 6,0(src)
sth 6,0(dst)
bflr 31
lbz 7,2(src)
stb 7,2(dst)
blr
.align 4
L(tail5):
bflr 31
lbz 6,4(src)
stb 6,4(dst)
blr
.align 4
1:
bflr 31
lbz 6,0(src)
stb 6,0(dst)
/* 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(src)
lwz 7,4(src)
stw 6,0(dst)
stw 7,4(dst)
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 dst quadword. */
srdi 9,cnt,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 cnt,0,cnt
/* 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(src)
addi src,src,1
stb 6,0(dst)
addi dst,dst,1
2:
bf 30,4f
lhz 6,0(src)
addi src,src,2
sth 6,0(dst)
addi dst,dst,2
4:
bf 29,8f
lwz 6,0(src)
addi src,src,4
stw 6,0(dst)
addi dst,dst,4
8:
bf 28,0f
ld 6,0(src)
addi src,src,8
std 6,0(dst)
addi dst,dst,8
0:
srdi 9,cnt,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,cnt,60
li 6,16 /* Index for 16-bytes offsets. */
li 7,32 /* Index for 32-bytes offsets. */
cmpldi cr1,10,0
srdi 8,cnt,5 /* Setup the loop counter. */
mtocrf 0x01,9
cmpldi cr6,9,1
#ifdef __LITTLE_ENDIAN__
lvsr 5,0,src
#else
lvsl 5,0,src
#endif
lvx 3,0,src
li 0,0
bf 31,L(setup_unaligned_loop)
/* Copy another 16 bytes to align to 32-bytes due to the loop. */
lvx 4,src,6
#ifdef __LITTLE_ENDIAN__
vperm 6,4,3,5
#else
vperm 6,3,4,5
#endif
addi src,src,16
stvx 6,0,dst
addi dst,dst,16
vor 3,4,4
clrrdi 0,src,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,src,6
#ifdef __LITTLE_ENDIAN__
vperm 6,4,3,5
#else
vperm 6,3,4,5
#endif
lvx 3,src,7
#ifdef __LITTLE_ENDIAN__
vperm 10,3,4,5
#else
vperm 10,4,3,5
#endif
addi src,src,32
stvx 6,0,dst
stvx 10,dst,6
addi dst,dst,32
bdnz L(unaligned_loop)
clrrdi 0,src,60
.align 4
L(end_unaligned_loop):
/* Check for tail bytes. */
mtocrf 0x01,cnt
beqlr cr1
add src,src,0
/* We have 1~15 tail bytes to copy, and DST is quadword aligned. */
/* Copy 8 bytes. */
bf 28,4f
lwz 6,0(src)
lwz 7,4(src)
addi src,src,8
stw 6,0(dst)
stw 7,4(dst)
addi dst,dst,8
4: /* Copy 4~7 bytes. */
bf 29,L(tail2)
lwz 6,0(src)
stw 6,0(dst)
bf 30,L(tail5)
lhz 7,4(src)
sth 7,4(dst)
bflr 31
lbz 8,6(src)
stb 8,6(dst)
/* Return original DST pointer. */
blr
END_GEN_TB (MEMCPY,TB_TOCLESS)
libc_hidden_builtin_def (memcpy)