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-rw-r--r--arch/sh/lib/memset.S57
1 files changed, 57 insertions, 0 deletions
diff --git a/arch/sh/lib/memset.S b/arch/sh/lib/memset.S
new file mode 100644
index 000000000000..95670090680e
--- /dev/null
+++ b/arch/sh/lib/memset.S
@@ -0,0 +1,57 @@
+/* $Id: memset.S,v 1.1 2000/04/14 16:49:01 mjd Exp $
+ *
+ * "memset" implementation of SuperH
+ *
+ * Copyright (C) 1999 Niibe Yutaka
+ *
+ */
+
+/*
+ * void *memset(void *s, int c, size_t n);
+ */
+
+#include <linux/linkage.h>
+
+ENTRY(memset)
+ tst r6,r6
+ bt/s 5f ! if n=0, do nothing
+ add r6,r4
+ mov #12,r0
+ cmp/gt r6,r0
+ bt/s 4f ! if it's too small, set a byte at once
+ mov r4,r0
+ and #3,r0
+ cmp/eq #0,r0
+ bt/s 2f ! It's aligned
+ sub r0,r6
+1:
+ dt r0
+ bf/s 1b
+ mov.b r5,@-r4
+2: ! make VVVV
+ swap.b r5,r0 ! V0
+ or r0,r5 ! VV
+ swap.w r5,r0 ! VV00
+ or r0,r5 ! VVVV
+ !
+ mov r6,r0
+ shlr2 r0
+ shlr r0 ! r0 = r6 >> 3
+3:
+ dt r0
+ mov.l r5,@-r4 ! set 8-byte at once
+ bf/s 3b
+ mov.l r5,@-r4
+ !
+ mov #7,r0
+ and r0,r6
+ tst r6,r6
+ bt 5f
+ ! fill bytes
+4:
+ dt r6
+ bf/s 4b
+ mov.b r5,@-r4
+5:
+ rts
+ mov r4,r0