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MiNT 0.95 pl13

|

| quickmove(char *dst, char *src, long nbytes):

| quickly copy "nbytes" bytes from src to dst. Assumes that both

| src and dst are word aligned.

|

	.text

	.globl	_quickmove

_quickmove:

	movel	sp@(4), a0		| get dst

	movel	sp@(8), a1		| get src

	movel	sp@(12), d0		| get nbytes

	lsrl	#8, d0			| 

	lsrl	#1, d0			| d0 = nbytes / 512

	subql	#1, d0			| prepare for dbra loop

	bmi	Leftover		| if < 0, skip

	moveml	d1-d7/a2-a6, sp@-	| save regs

L1:

	moveml	a1@+, d1-d7/a2-a6	| read 12*4 = 48 bytes

	moveml	d1-d7/a2-a6, a0@	|

	moveml	a1@+, d1-d7/a2-a6	| 2nd read

	moveml	d1-d7/a2-a6, a0@(48)	|

	moveml	a1@+, d1-d7/a2-a6	| 3rd read

	moveml	d1-d7/a2-a6, a0@(96)	|

	moveml	a1@+, d1-d7/a2-a6	| 4th read

	moveml	d1-d7/a2-a6, a0@(144)	|

	moveml	a1@+, d1-d7/a2-a6	| 5th

	moveml	d1-d7/a2-a6, a0@(192)	|

	moveml	a1@+, d1-d7/a2-a6	| 6th

	moveml	d1-d7/a2-a6, a0@(240)	|

	moveml	a1@+, d1-d7/a2-a6	| 7th

	moveml	d1-d7/a2-a6, a0@(288)	|

	moveml	a1@+, d1-d7/a2-a6	| 8th

	moveml	d1-d7/a2-a6, a0@(336)	|

	moveml	a1@+, d1-d7/a2-a6	| 9th

	moveml	d1-d7/a2-a6, a0@(384)	|

	moveml	a1@+, d1-d7/a2-a6	| 10th

	moveml	d1-d7/a2-a6, a0@(432)	| At this point, 480 bytes done

	moveml	a1@+, d1-d7/a2		| Only do 32 more bytes

	moveml	d1-d7/a2, a0@(480)	| for a total of 512



	lea	a0@(512), a0

	subql	#1, d0

	bge	L1



	moveml	sp@+, d1-d7/a2-a6	| pop registers



Leftover:				| do the remaining bytes

	movel	sp@(12), d1

	andl	#0x01ff, d1		| d1 = nbytes % 512

	subql	#1, d1			| prepare for dbra loop

	bmi	Ldone

L2:

	moveb	a1@+, a0@+

	dbra	d1, L2

Ldone:

	rts				| return

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