WSL2-Linux-Kernel/arch/sh/lib64/strcpy.S

99 строки
1.9 KiB
ArmAsm

/* SPDX-License-Identifier: GPL-2.0 */
/* Cloned and hacked for uClibc by Paul Mundt, December 2003 */
/* Modified by SuperH, Inc. September 2003 */
! Entry: arg0: destination
! arg1: source
! Exit: result: destination
!
! SH5 code Copyright 2002 SuperH Ltd.
#if __BYTE_ORDER == __LITTLE_ENDIAN
#define SHHI shlld
#define SHLO shlrd
#else
#define SHHI shlrd
#define SHLO shlld
#endif
.section .text..SHmedia32,"ax"
.globl strcpy
.type strcpy, @function
.align 5
strcpy:
pta/l shortstring,tr1
ldlo.q r3,0,r4
ptabs r18,tr4
shlli r3,3,r7
addi r2, 8, r0
mcmpeq.b r4,r63,r6
SHHI r6,r7,r6
bnei/u r6,0,tr1 // shortstring
pta/l no_lddst, tr2
ori r3,-8,r23
sub r2, r23, r0
sub r3, r2, r21
addi r21, 8, r20
ldx.q r0, r21, r5
pta/l loop, tr0
ori r2,-8,r22
mcmpeq.b r5, r63, r6
bgt/u r22, r23, tr2 // no_lddst
// r22 < r23 : Need to do a load from the destination.
// r22 == r23 : Doesn't actually need to load from destination,
// but still can be handled here.
ldlo.q r2, 0, r9
movi -1, r8
SHLO r8, r7, r8
mcmv r4, r8, r9
stlo.q r2, 0, r9
beqi/l r6, 0, tr0 // loop
add r5, r63, r4
addi r0, 8, r0
blink tr1, r63 // shortstring
no_lddst:
// r22 > r23: note that for r22 == r23 the sthi.q would clobber
// bytes before the destination region.
stlo.q r2, 0, r4
SHHI r4, r7, r4
sthi.q r0, -1, r4
beqi/l r6, 0, tr0 // loop
add r5, r63, r4
addi r0, 8, r0
shortstring:
#if __BYTE_ORDER != __LITTLE_ENDIAN
pta/l shortstring2,tr1
byterev r4,r4
#endif
shortstring2:
st.b r0,-8,r4
andi r4,0xff,r5
shlri r4,8,r4
addi r0,1,r0
bnei/l r5,0,tr1
blink tr4,r63 // return
.balign 8
loop:
stlo.q r0, 0, r5
ldx.q r0, r20, r4
addi r0, 16, r0
sthi.q r0, -9, r5
mcmpeq.b r4, r63, r6
bnei/u r6, 0, tr1 // shortstring
ldx.q r0, r21, r5
stlo.q r0, -8, r4
sthi.q r0, -1, r4
mcmpeq.b r5, r63, r6
beqi/l r6, 0, tr0 // loop
add r5, r63, r4
addi r0, 8, r0
blink tr1, r63 // shortstring
.size strcpy,.-strcpy