linux/arch/powerpc/lib/mem_64.S
Anton Blanchard be54c1216f powerpc/64: Remove static branch hints from memset()
Static branch hints override dynamic branch prediction on recent
POWER CPUs. We should only use them when we are overwhelmingly
sure of the direction.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-09-17 21:17:25 +10:00

142 lines
2.3 KiB
ArmAsm

/*
* String handling functions for PowerPC.
*
* Copyright (C) 1996 Paul Mackerras.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <asm/processor.h>
#include <asm/errno.h>
#include <asm/ppc_asm.h>
#include <asm/export.h>
_GLOBAL(__memset16)
rlwimi r4,r4,16,0,15
/* fall through */
_GLOBAL(__memset32)
rldimi r4,r4,32,0
/* fall through */
_GLOBAL(__memset64)
neg r0,r3
andi. r0,r0,7
cmplw cr1,r5,r0
b .Lms
EXPORT_SYMBOL(__memset16)
EXPORT_SYMBOL(__memset32)
EXPORT_SYMBOL(__memset64)
_GLOBAL(memset)
neg r0,r3
rlwimi r4,r4,8,16,23
andi. r0,r0,7 /* # bytes to be 8-byte aligned */
rlwimi r4,r4,16,0,15
cmplw cr1,r5,r0 /* do we get that far? */
rldimi r4,r4,32,0
.Lms: PPC_MTOCRF(1,r0)
mr r6,r3
blt cr1,8f
beq 3f /* if already 8-byte aligned */
subf r5,r0,r5
bf 31,1f
stb r4,0(r6)
addi r6,r6,1
1: bf 30,2f
sth r4,0(r6)
addi r6,r6,2
2: bf 29,3f
stw r4,0(r6)
addi r6,r6,4
3: srdi. r0,r5,6
clrldi r5,r5,58
mtctr r0
beq 5f
.balign 16
4: std r4,0(r6)
std r4,8(r6)
std r4,16(r6)
std r4,24(r6)
std r4,32(r6)
std r4,40(r6)
std r4,48(r6)
std r4,56(r6)
addi r6,r6,64
bdnz 4b
5: srwi. r0,r5,3
clrlwi r5,r5,29
PPC_MTOCRF(1,r0)
beq 8f
bf 29,6f
std r4,0(r6)
std r4,8(r6)
std r4,16(r6)
std r4,24(r6)
addi r6,r6,32
6: bf 30,7f
std r4,0(r6)
std r4,8(r6)
addi r6,r6,16
7: bf 31,8f
std r4,0(r6)
addi r6,r6,8
8: cmpwi r5,0
PPC_MTOCRF(1,r5)
beqlr
bf 29,9f
stw r4,0(r6)
addi r6,r6,4
9: bf 30,10f
sth r4,0(r6)
addi r6,r6,2
10: bflr 31
stb r4,0(r6)
blr
EXPORT_SYMBOL(memset)
_GLOBAL_TOC(memmove)
cmplw 0,r3,r4
bgt backwards_memcpy
b memcpy
_GLOBAL(backwards_memcpy)
rlwinm. r7,r5,32-3,3,31 /* r0 = r5 >> 3 */
add r6,r3,r5
add r4,r4,r5
beq 2f
andi. r0,r6,3
mtctr r7
bne 5f
.balign 16
1: lwz r7,-4(r4)
lwzu r8,-8(r4)
stw r7,-4(r6)
stwu r8,-8(r6)
bdnz 1b
andi. r5,r5,7
2: cmplwi 0,r5,4
blt 3f
lwzu r0,-4(r4)
subi r5,r5,4
stwu r0,-4(r6)
3: cmpwi 0,r5,0
beqlr
mtctr r5
4: lbzu r0,-1(r4)
stbu r0,-1(r6)
bdnz 4b
blr
5: mtctr r0
6: lbzu r7,-1(r4)
stbu r7,-1(r6)
bdnz 6b
subf r5,r0,r5
rlwinm. r7,r5,32-3,3,31
beq 2b
mtctr r7
b 1b
EXPORT_SYMBOL(memmove)