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.text
.syntax unified
.global memset
.func memset
.thumb_func
memset:
/* on entry
* r0 = targ
* r1 = value
* r2 = len (bytes)
* on exit
* r0 = targ (unchanged)
*/
push {r0, r4, lr}
/* If targ is unaligned, drop to byte
* processing. */
movs r3, #3
ands r3, r0
bne L_bytewise
/* Process words */
/* Build r4 by repeating r1. */
uxtb r4, r1
lsls r3, r4, #8
orrs r4, r3
lsls r3, r4, #16
orrs r4, r3
L_wordwise:
cmp r2, #4
blo L_bytewise
str r4, [r0]
adds r0, #4
subs r2, #4
b L_wordwise
/* Process bytes */
L_bytewise:
cmp r2, #0
beq L_fin
strb r1, [r0]
adds r0, #1
subs r2, #1
b L_bytewise
L_fin:
pop {r0, r4, pc}
.endfunc
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