summaryrefslogtreecommitdiff
path: root/arch/sparc/lib/memmove.S
diff options
context:
space:
mode:
Diffstat (limited to 'arch/sparc/lib/memmove.S')
-rw-r--r--arch/sparc/lib/memmove.S59
1 files changed, 59 insertions, 0 deletions
diff --git a/arch/sparc/lib/memmove.S b/arch/sparc/lib/memmove.S
new file mode 100644
index 000000000..857ad4f89
--- /dev/null
+++ b/arch/sparc/lib/memmove.S
@@ -0,0 +1,59 @@
+/* memmove.S: Simple memmove implementation.
+ *
+ * Copyright (C) 1997, 2004 David S. Miller (davem@redhat.com)
+ * Copyright (C) 1996, 1997, 1998, 1999 Jakub Jelinek (jj@ultra.linux.cz)
+ */
+
+#include <linux/linkage.h>
+
+ .text
+ENTRY(memmove) /* o0=dst o1=src o2=len */
+ brz,pn %o2, 99f
+ mov %o0, %g1
+
+ cmp %o0, %o1
+ bleu,pt %xcc, 2f
+ add %o1, %o2, %g7
+ cmp %g7, %o0
+ bleu,pt %xcc, memcpy
+ add %o0, %o2, %o5
+ sub %g7, 1, %o1
+
+ sub %o5, 1, %o0
+1: ldub [%o1], %g7
+ subcc %o2, 1, %o2
+ sub %o1, 1, %o1
+ stb %g7, [%o0]
+ bne,pt %icc, 1b
+ sub %o0, 1, %o0
+99:
+ retl
+ mov %g1, %o0
+
+ /* We can't just call memcpy for these memmove cases. On some
+ * chips the memcpy uses cache initializing stores and when dst
+ * and src are close enough, those can clobber the source data
+ * before we've loaded it in.
+ */
+2: or %o0, %o1, %g7
+ or %o2, %g7, %g7
+ andcc %g7, 0x7, %g0
+ bne,pn %xcc, 4f
+ nop
+
+3: ldx [%o1], %g7
+ add %o1, 8, %o1
+ subcc %o2, 8, %o2
+ add %o0, 8, %o0
+ bne,pt %icc, 3b
+ stx %g7, [%o0 - 0x8]
+ ba,a,pt %xcc, 99b
+
+4: ldub [%o1], %g7
+ add %o1, 1, %o1
+ subcc %o2, 1, %o2
+ add %o0, 1, %o0
+ bne,pt %icc, 4b
+ stb %g7, [%o0 - 0x1]
+ ba,a,pt %xcc, 99b
+ENDPROC(memmove)