255 lines
		
	
	
	
		
			3.9 KiB
			
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
		
		
			
		
	
	
			255 lines
		
	
	
	
		
			3.9 KiB
			
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
|   | /* $Id: memmove.S,v 1.2 2001/07/27 11:51:09 gniibe Exp $ | ||
|  |  * | ||
|  |  * "memmove" implementation of SuperH | ||
|  |  * | ||
|  |  * Copyright (C) 1999  Niibe Yutaka | ||
|  |  * | ||
|  |  */ | ||
|  | 
 | ||
|  | /* | ||
|  |  * void *memmove(void *dst, const void *src, size_t n);
 | ||
|  |  * The memory areas may overlap. | ||
|  |  */ | ||
|  | 
 | ||
|  | #include <linux/linkage.h> | ||
|  | ENTRY(memmove) | ||
|  | 	! if dest > src, call memcpy (it copies in decreasing order) | ||
|  | 	cmp/hi	r5,r4 | ||
|  | 	bf	1f | ||
|  | 	mov.l	2f,r0 | ||
|  | 	jmp	@r0
 | ||
|  | 	 nop | ||
|  | 	.balign 4
 | ||
|  | 2:	.long	memcpy | ||
|  | 1: | ||
|  | 	sub	r5,r4		! From here, r4 has the distance to r0 | ||
|  | 	tst	r6,r6 | ||
|  | 	bt/s	9f		! if n=0, do nothing | ||
|  | 	 mov	r5,r0 | ||
|  | 	add	r6,r5 | ||
|  | 	mov	#12,r1 | ||
|  | 	cmp/gt	r6,r1 | ||
|  | 	bt/s	8f		! if it's too small, copy a byte at once | ||
|  | 	 add	#-1,r4 | ||
|  | 	add	#1,r4 | ||
|  | 	! | ||
|  | 	!                [ ...  ] DST             [ ...  ] SRC | ||
|  | 	!	         [ ...  ]                 [ ...  ] | ||
|  | 	!	           :                        : | ||
|  | 	!      r0+r4-->  [ ...  ]       r0    --> [ ...  ] | ||
|  | 	!	           :                        : | ||
|  | 	!	         [ ...  ]                 [ ...  ] | ||
|  | 	!			        r5    --> | ||
|  | 	! | ||
|  | 	mov	r4,r1 | ||
|  | 	mov	#3,r2 | ||
|  | 	and	r2,r1 | ||
|  | 	shll2	r1 | ||
|  | 	mov	r0,r3		! Save the value on R0 to R3 | ||
|  | 	mova	jmptable,r0 | ||
|  | 	add	r1,r0 | ||
|  | 	mov.l	@r0,r1
 | ||
|  | 	jmp	@r1
 | ||
|  | 	 mov	r3,r0		! and back to R0 | ||
|  | 	.balign	4
 | ||
|  | jmptable: | ||
|  | 	.long	case0
 | ||
|  | 	.long	case1
 | ||
|  | 	.long	case2
 | ||
|  | 	.long	case3
 | ||
|  | 
 | ||
|  | 	! copy a byte at once | ||
|  | 8:	mov.b	@r0+,r1
 | ||
|  | 	cmp/hs	r5,r0 | ||
|  | 	bf/s	8b			! while (r0<r5) | ||
|  | 	 mov.b	r1,@(r0,r4)
 | ||
|  | 	add	#1,r4 | ||
|  | 9: | ||
|  | 	add	r4,r0 | ||
|  | 	rts | ||
|  | 	 sub	r6,r0 | ||
|  | 
 | ||
|  | case_none: | ||
|  | 	bra	8b | ||
|  | 	 add	#-1,r4 | ||
|  | 
 | ||
|  | case0: | ||
|  | 	! | ||
|  | 	!	GHIJ KLMN OPQR -->  GHIJ KLMN OPQR | ||
|  | 	! | ||
|  | 	! First, align to long word boundary | ||
|  | 	mov	r0,r3 | ||
|  | 	and	r2,r3 | ||
|  | 	tst	r3,r3 | ||
|  | 	bt/s	2f | ||
|  | 	 add	#-1,r4 | ||
|  | 	mov	#4,r2 | ||
|  | 	sub	r3,r2 | ||
|  | 1:	dt	r2 | ||
|  | 	mov.b	@r0+,r1
 | ||
|  | 	bf/s	1b | ||
|  | 	 mov.b	r1,@(r0,r4)
 | ||
|  | 	! | ||
|  | 2:	! Second, copy a long word at once | ||
|  | 	add	#-3,r4 | ||
|  | 	add	#-3,r5 | ||
|  | 3:	mov.l	@r0+,r1
 | ||
|  | 	cmp/hs	r5,r0 | ||
|  | 	bf/s	3b | ||
|  | 	 mov.l	r1,@(r0,r4)
 | ||
|  | 	add	#3,r5 | ||
|  | 	! | ||
|  | 	! Third, copy a byte at once, if necessary | ||
|  | 	cmp/eq	r5,r0 | ||
|  | 	bt/s	9b | ||
|  | 	 add	#4,r4 | ||
|  | 	bra	8b | ||
|  | 	 add	#-1,r4 | ||
|  | 
 | ||
|  | case3: | ||
|  | 	! | ||
|  | 	!	GHIJ KLMN OPQR -->  ...G HIJK LMNO PQR. | ||
|  | 	! | ||
|  | 	! First, align to long word boundary | ||
|  | 	mov	r0,r3 | ||
|  | 	and	r2,r3 | ||
|  | 	tst	r3,r3 | ||
|  | 	bt/s	2f | ||
|  | 	 add	#-1,r4 | ||
|  | 	mov	#4,r2 | ||
|  | 	sub	r3,r2 | ||
|  | 1:	dt	r2 | ||
|  | 	mov.b	@r0+,r1
 | ||
|  | 	bf/s	1b | ||
|  | 	 mov.b	r1,@(r0,r4)
 | ||
|  | 	! | ||
|  | 2:	! Second, read a long word and write a long word at once | ||
|  | 	add	#-2,r4 | ||
|  | 	mov.l	@(r0,r4),r1
 | ||
|  | 	add	#-7,r5 | ||
|  | 	add	#-4,r4 | ||
|  | 	! | ||
|  | #ifdef __LITTLE_ENDIAN__ | ||
|  | 	shll8	r1 | ||
|  | 3:	mov	r1,r3		! JIHG | ||
|  | 	shlr8	r3		! xJIH | ||
|  | 	mov.l	@r0+,r1		! NMLK
 | ||
|  | 	mov	r1,r2 | ||
|  | 	shll16	r2 | ||
|  | 	shll8	r2		! Kxxx | ||
|  | 	or	r2,r3		! KJIH | ||
|  | 	cmp/hs	r5,r0 | ||
|  | 	bf/s	3b | ||
|  | 	 mov.l	r3,@(r0,r4)
 | ||
|  | #else | ||
|  | 	shlr8	r1 | ||
|  | 3:	mov	r1,r3		! GHIJ | ||
|  | 	shll8	r3		! HIJx | ||
|  | 	mov.l	@r0+,r1		! KLMN
 | ||
|  | 	mov	r1,r2 | ||
|  | 	shlr16	r2 | ||
|  | 	shlr8	r2		! xxxK | ||
|  | 	or	r2,r3		! HIJK | ||
|  | 	cmp/hs	r5,r0 | ||
|  | 	bf/s	3b | ||
|  | 	 mov.l	r3,@(r0,r4)
 | ||
|  | #endif | ||
|  | 	add	#7,r5 | ||
|  | 	! | ||
|  | 	! Third, copy a byte at once, if necessary | ||
|  | 	cmp/eq	r5,r0 | ||
|  | 	bt/s	9b | ||
|  | 	 add	#7,r4 | ||
|  | 	add	#-3,r0 | ||
|  | 	bra	8b | ||
|  | 	 add	#-1,r4 | ||
|  | 
 | ||
|  | case2: | ||
|  | 	! | ||
|  | 	!	GHIJ KLMN OPQR -->  ..GH IJKL MNOP QR.. | ||
|  | 	! | ||
|  | 	! First, align to word boundary | ||
|  | 	tst	#1,r0 | ||
|  | 	bt/s	2f | ||
|  | 	 add	#-1,r4 | ||
|  | 	mov.b	@r0+,r1
 | ||
|  | 	mov.b	r1,@(r0,r4)
 | ||
|  | 	! | ||
|  | 2:	! Second, read a word and write a word at once | ||
|  | 	add	#-1,r4 | ||
|  | 	add	#-1,r5 | ||
|  | 	! | ||
|  | 3:	mov.w	@r0+,r1
 | ||
|  | 	cmp/hs	r5,r0 | ||
|  | 	bf/s	3b | ||
|  | 	 mov.w	r1,@(r0,r4)
 | ||
|  | 	add	#1,r5 | ||
|  | 	! | ||
|  | 	! Third, copy a byte at once, if necessary | ||
|  | 	cmp/eq	r5,r0 | ||
|  | 	bt/s	9b | ||
|  | 	 add	#2,r4 | ||
|  | 	mov.b	@r0,r1
 | ||
|  | 	mov.b	r1,@(r0,r4)
 | ||
|  | 	bra	9b | ||
|  | 	 add	#1,r0 | ||
|  | 
 | ||
|  | case1: | ||
|  | 	! | ||
|  | 	!	GHIJ KLMN OPQR -->  .GHI JKLM NOPQ R... | ||
|  | 	! | ||
|  | 	! First, align to long word boundary | ||
|  | 	mov	r0,r3 | ||
|  | 	and	r2,r3 | ||
|  | 	tst	r3,r3 | ||
|  | 	bt/s	2f | ||
|  | 	 add	#-1,r4 | ||
|  | 	mov	#4,r2 | ||
|  | 	sub	r3,r2 | ||
|  | 1:	dt	r2 | ||
|  | 	mov.b	@r0+,r1
 | ||
|  | 	bf/s	1b | ||
|  | 	 mov.b	r1,@(r0,r4)
 | ||
|  | 	! | ||
|  | 2:	! Second, read a long word and write a long word at once | ||
|  | 	mov.l	@(r0,r4),r1
 | ||
|  | 	add	#-7,r5 | ||
|  | 	add	#-4,r4 | ||
|  | 	! | ||
|  | #ifdef __LITTLE_ENDIAN__ | ||
|  | 	shll16	r1 | ||
|  | 	shll8	r1 | ||
|  | 3:	mov	r1,r3		! JIHG | ||
|  | 	shlr16	r3 | ||
|  | 	shlr8	r3		! xxxJ | ||
|  | 	mov.l	@r0+,r1		! NMLK
 | ||
|  | 	mov	r1,r2 | ||
|  | 	shll8	r2		! MLKx | ||
|  | 	or	r2,r3		! MLKJ | ||
|  | 	cmp/hs	r5,r0 | ||
|  | 	bf/s	3b | ||
|  | 	 mov.l	r3,@(r0,r4)
 | ||
|  | #else | ||
|  | 	shlr16	r1 | ||
|  | 	shlr8	r1 | ||
|  | 3:	mov	r1,r3		! GHIJ | ||
|  | 	shll16	r3 | ||
|  | 	shll8	r3		! Jxxx | ||
|  | 	mov.l	@r0+,r1		! KLMN
 | ||
|  | 	mov	r1,r2 | ||
|  | 	shlr8	r2		! xKLM | ||
|  | 	or	r2,r3		! JKLM | ||
|  | 	cmp/hs	r5,r0 | ||
|  | 	bf/s	3b		! while(r0<r5) | ||
|  | 	 mov.l	r3,@(r0,r4)
 | ||
|  | #endif | ||
|  | 	add	#7,r5 | ||
|  | 	! | ||
|  | 	! Third, copy a byte at once, if necessary | ||
|  | 	cmp/eq	r5,r0 | ||
|  | 	bt/s	9b | ||
|  | 	 add	#5,r4 | ||
|  | 	add	#-3,r0 | ||
|  | 	bra	8b | ||
|  | 	 add	#-1,r4 |