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-rw-r--r--newlib/libc/machine/h8300/memcpy.S48
1 files changed, 48 insertions, 0 deletions
diff --git a/newlib/libc/machine/h8300/memcpy.S b/newlib/libc/machine/h8300/memcpy.S
new file mode 100644
index 00000000000..3465ce55885
--- /dev/null
+++ b/newlib/libc/machine/h8300/memcpy.S
@@ -0,0 +1,48 @@
+#include "defines.h"
+
+#ifdef __H8300H__
+ .h8300h
+#endif
+
+#ifdef __H8300S__
+ .h8300s
+#endif
+
+ .global _memcpy
+_memcpy:
+; MOVP @(2/4,r7),A0P ; dst
+; MOVP @(4/8,r7),A1P ; src
+; MOVP @(6/12,r7),A2P ; len
+
+ MOVP A0P,A3P ; keep copy of final dst
+ ADDP A2P,A0P ; point to end of dst
+ CMPP A0P,A3P ; see if anything to do
+ beq quit
+
+ ADDP A2P,A1P ; point to end of src
+
+ ; lets see if we can do this in words
+ or A0L,A2L ; or in the dst address
+ or A3L,A2L ; or the length
+ or A1L,A2L ; or the src address
+ btst #0,A2L ; see if the lsb is zero
+ bne byteloop
+
+wordloop:
+ subs #2,A1P ; point to word
+ mov.w @A1P,A2 ; get word
+ mov.w A2,@-A0P ; save word
+ CMPP A0P,A3P ; at the front again ?
+ bne wordloop
+ rts
+
+byteloop:
+ subs #1,A1P ; point to byte
+ mov.b @A1P,A2L ; get byte
+ mov.b A2L,@-A0P ; save byte
+ CMPP A0P,A3P ; at the front again ?
+ bne byteloop
+
+ ; return with A0 pointing to dst
+quit: rts
+