Initial import

1 files changed, 227 insertions, 0 deletions

diff --git a/arch/sh/lib/memcpy.S b/arch/sh/lib/memcpy.S
new file mode 100644
index 000000000..232fab34c
--- /dev/null
+++ b/arch/sh/lib/memcpy.S
@@ -0,0 +1,227 @@
+/* $Id: memcpy.S,v 1.3 2001/07/27 11:50:52 gniibe Exp $
+ *
+ * "memcpy" implementation of SuperH
+ *
+ * Copyright (C) 1999  Niibe Yutaka
+ *
+ */
+
+/*
+ * void *memcpy(void *dst, const void *src, size_t n);
+ * No overlap between the memory of DST and of SRC are assumed.
+ */
+
+#include <linux/linkage.h>
+ENTRY(memcpy)
+	tst	r6,r6
+	bt/s	9f		! if n=0, do nothing
+	 mov	r4,r0
+	sub	r4,r5		! From here, r5 has the distance to r0
+	add	r6,r0		! From here, r0 points the end of copying point
+	mov	#12,r1
+	cmp/gt	r6,r1
+	bt/s	7f		! if it's too small, copy a byte at once
+	 add	#-1,r5
+	add	#1,r5
+	!			From here, r6 is free
+	!
+	!      r4   -->  [ ...  ] DST             [ ...  ] SRC
+	!	         [ ...  ]                 [ ...  ]
+	!	           :                        :
+	!      r0   -->  [ ...  ]       r0+r5 --> [ ...  ]
+	!
+	!
+	mov	r5,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
+7:	mov	r4,r2
+	add	#1,r2
+8:
+	cmp/hi	r2,r0
+	mov.b	@(r0,r5),r1
+	bt/s	8b			! while (r0>r2)
+	 mov.b	r1,@-r0
+9:
+	rts
+	 nop
+
+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	#-4,r5
+	add	#3,r5
+1:	dt	r3
+	mov.b	@(r0,r5),r1
+	bf/s	1b
+	 mov.b	r1,@-r0
+	!
+	add	#-3,r5
+2:	! Second, copy a long word at once
+	mov	r4,r2
+	add	#7,r2
+3:	mov.l	@(r0,r5),r1
+	cmp/hi	r2,r0
+	bt/s	3b
+	 mov.l	r1,@-r0
+	!
+	! Third, copy a byte at once, if necessary
+	cmp/eq	r4,r0
+	bt/s	9b
+	 add	#3,r5
+	bra	8b
+	 add	#-6,r2
+
+case1:
+	!
+	!	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,r5
+1:	dt	r3
+	mov.b	@(r0,r5),r1
+	bf/s	1b
+	 mov.b	r1,@-r0
+	!
+2:	! Second, read a long word and write a long word at once
+	mov.l	@(r0,r5),r1
+	add	#-4,r5
+	mov	r4,r2
+	add	#7,r2
+	!
+#ifdef __LITTLE_ENDIAN__
+3:	mov	r1,r3		! RQPO
+	shll16	r3
+	shll8	r3		! Oxxx
+	mov.l	@(r0,r5),r1	! NMLK
+	mov	r1,r6
+	shlr8	r6		! xNML
+	or	r6,r3		! ONML
+	cmp/hi	r2,r0
+	bt/s	3b
+	 mov.l	r3,@-r0
+#else
+3:	mov	r1,r3		! OPQR
+	shlr16	r3
+	shlr8	r3		! xxxO
+	mov.l	@(r0,r5),r1	! KLMN
+	mov	r1,r6
+	shll8	r6		! LMNx
+	or	r6,r3		! LMNO
+	cmp/hi	r2,r0
+	bt/s	3b
+	 mov.l	r3,@-r0
+#endif
+	!
+	! Third, copy a byte at once, if necessary
+	cmp/eq	r4,r0
+	bt/s	9b
+	 add	#4,r5
+	bra	8b
+	 add	#-6,r2
+
+case2:
+	!
+	!	GHIJ KLMN OPQR -->  ..GH IJKL MNOP QR..
+	!
+	! First, align to word boundary
+	tst	#1,r0
+	bt/s	2f
+	 add	#-1,r5
+	mov.b	@(r0,r5),r1
+	mov.b	r1,@-r0
+	!
+2:	! Second, read a word and write a word at once
+	add	#-1,r5
+	mov	r4,r2
+	add	#3,r2
+	!
+3:	mov.w	@(r0,r5),r1
+	cmp/hi	r2,r0
+	bt/s	3b
+	 mov.w	r1,@-r0
+	!
+	! Third, copy a byte at once, if necessary
+	cmp/eq	r4,r0
+	bt/s	9b
+	 add	#1,r5
+	mov.b	@(r0,r5),r1
+	rts
+	 mov.b	r1,@-r0
+
+case3:
+	!
+	!	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,r5
+1:	dt	r3
+	mov.b	@(r0,r5),r1
+	bf/s	1b
+	 mov.b	r1,@-r0
+	!
+2:	! Second, read a long word and write a long word at once
+	add	#-2,r5
+	mov.l	@(r0,r5),r1
+	add	#-4,r5
+	mov	r4,r2
+	add	#7,r2
+	!
+#ifdef __LITTLE_ENDIAN__
+3:	mov	r1,r3		! RQPO
+	shll8	r3		! QPOx
+	mov.l	@(r0,r5),r1	! NMLK
+	mov	r1,r6
+	shlr16	r6
+	shlr8	r6		! xxxN
+	or	r6,r3		! QPON
+	cmp/hi	r2,r0
+	bt/s	3b
+	 mov.l	r3,@-r0
+#else
+3:	mov	r1,r3		! OPQR
+	shlr8	r3		! xOPQ
+	mov.l	@(r0,r5),r1	! KLMN
+	mov	r1,r6
+	shll16	r6
+	shll8	r6		! Nxxx
+	or	r6,r3		! NOPQ
+	cmp/hi	r2,r0
+	bt/s	3b
+	 mov.l	r3,@-r0
+#endif
+	!
+	! Third, copy a byte at once, if necessary
+	cmp/eq	r4,r0
+	bt/s	9b
+	 add	#6,r5
+	bra	8b
+	 add	#-6,r2