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@ vim:filetype=armasm
@ Generic memory routines.
@ (c) Copyright 2007, Grazvydas "notaz" Ignotas
.global memcpy16 @ unsigned short *dest, unsigned short *src, int count
memcpy16:
eor r3, r0, r1
tst r3, #2
bne mcp16_cant_align
tst r0, #2
ldrneh r3, [r1], #2
subne r2, r2, #1
strneh r3, [r0], #2
subs r2, r2, #4
bmi mcp16_fin
mcp16_loop:
ldmia r1!, {r3,r12}
subs r2, r2, #4
stmia r0!, {r3,r12}
bpl mcp16_loop
mcp16_fin:
tst r2, #2
ldrne r3, [r1], #4
strne r3, [r0], #4
ands r2, r2, #1
bxeq lr
mcp16_cant_align:
ldrh r3, [r1], #2
subs r2, r2, #1
strh r3, [r0], #2
bne mcp16_cant_align
bx lr
@ 0x12345678 -> 0x34127856
@ r4=temp, lr=0x00ff00ff
.macro bswap reg
and r4, \reg, lr
and \reg, lr, \reg, lsr #8
orr \reg, \reg, r4, lsl #8
.endm
@ dest must be halfword aligned, src can be unaligned
.global memcpy16bswap @ unsigned short *dest, void *src, int count
memcpy16bswap:
tst r1, #1
bne mcp16bs_cant_align2
eor r3, r0, r1
tst r3, #2
bne mcp16bs_cant_align
tst r0, #2
beq mcp16bs_aligned
ldrh r3, [r1], #2
sub r2, r2, #1
orr r3, r3, r3, lsl #16
mov r3, r3, lsr #8
strh r3, [r0], #2
mcp16bs_aligned:
stmfd sp!, {r4,lr}
mov lr, #0xff
orr lr, lr, lr, lsl #16
subs r2, r2, #4
bmi mcp16bs_fin4
mcp16bs_loop:
ldmia r1!, {r3,r12}
subs r2, r2, #4
bswap r3
bswap r12
stmia r0!, {r3,r12}
bpl mcp16bs_loop
mcp16bs_fin4:
tst r2, #2
beq mcp16bs_fin2
ldr r3, [r1], #4
bswap r3
str r3, [r0], #4
mcp16bs_fin2:
ldmfd sp!, {r4,lr}
ands r2, r2, #1
bxeq lr
mcp16bs_cant_align:
ldrh r3, [r1], #2
subs r2, r2, #1
orr r3, r3, r3, lsl #16
mov r3, r3, lsr #8
strh r3, [r0], #2
bne mcp16bs_cant_align
bx lr
@ worst case
mcp16bs_cant_align2:
ldrb r3, [r1], #1
ldrb r12,[r1], #1
subs r2, r2, #1
mov r3, r3, lsl #8
orr r3, r3, r12
strh r3, [r0], #2
bne mcp16bs_cant_align2
bx lr
.global memcpy32 @ int *dest, int *src, int count
memcpy32:
stmfd sp!, {r4,lr}
subs r2, r2, #4
bmi mcp32_fin
mcp32_loop:
ldmia r1!, {r3,r4,r12,lr}
subs r2, r2, #4
stmia r0!, {r3,r4,r12,lr}
bpl mcp32_loop
mcp32_fin:
tst r2, #3
ldmeqfd sp!, {r4,pc}
tst r2, #1
ldrne r3, [r1], #4
strne r3, [r0], #4
mcp32_no_unal1:
tst r2, #2
ldmneia r1!, {r3,r12}
ldmfd sp!, {r4,lr}
stmneia r0!, {r3,r12}
bx lr
.global memset32 @ int *dest, int c, int count
memset32:
stmfd sp!, {lr}
mov r3, r1
subs r2, r2, #4
bmi mst32_fin
mov r12,r1
mov lr, r1
mst32_loop:
subs r2, r2, #4
stmia r0!, {r1,r3,r12,lr}
bpl mst32_loop
mst32_fin:
tst r2, #1
strne r1, [r0], #4
tst r2, #2
stmneia r0!, {r1,r3}
ldmfd sp!, {pc}
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