install copy predefined

did not test 386, but should work
shouldnt matter if copy is not used

R=rsc
https://golang.org/cl/156055

4 files changed, 164 insertions, 0 deletions

diff --git a/src/pkg/runtime/Makefile b/src/pkg/runtime/Makefile
index 08bf278ef4..3c97c495f6 100644
--- a/src/pkg/runtime/Makefile
+++ b/src/pkg/runtime/Makefile
@@ -68,6 +68,7 @@ OFILES=\
 	sys.$O\
 	thread.$O\
 	traceback.$O\
+	memmove_$(GOARCH).$O\
 	$(OFILES_$(GOARCH))\
 
 HFILES=\
diff --git a/src/pkg/runtime/memmove_386.s b/src/pkg/runtime/memmove_386.s
new file mode 100644
index 0000000000..f7bc402590
--- /dev/null
+++ b/src/pkg/runtime/memmove_386.s
@@ -0,0 +1,65 @@
+	TEXT	memmove(SB), $0
+
+	MOVL	to+0(FP), DI
+	MOVL	fr+4(FP), SI
+	MOVL	n+8(FP), BX
+	JLT	fault
+
+/*
+ * check and set for backwards
+ * should we look closer for overlap?
+ */
+	CMPL	SI, DI
+	JLS	back
+
+/*
+ * foreward copy loop
+ */
+	MOVL	BX, CX
+	SHRL	$2, CX
+	ANDL	$3, BX
+
+	REP;	MOVSL
+	MOVL	BX, CX
+	REP;	MOVSB
+
+	MOVL	to+0(FP),AX
+	RET
+/*
+ * whole thing backwards has
+ * adjusted addresses
+ */
+back:
+	ADDL	BX, DI
+	ADDL	BX, SI
+	STD
+
+/*
+ * copy
+ */
+	MOVL	BX, CX
+	SHRL	$2, CX
+	ANDL	$3, BX
+
+	SUBL	$4, DI
+	SUBL	$4, SI
+	REP;	MOVSL
+
+	ADDL	$3, DI
+	ADDL	$3, SI
+	MOVL	BX, CX
+	REP;	MOVSB
+
+	CLD
+	MOVL	to+0(FP),AX
+	RET
+
+/*
+ * if called with negative count,
+ * treat as error rather than
+ * rotating all of memory
+ */
+fault:
+	MOVL	$0,SI
+	MOVL	0(SI), AX
+	RET
diff --git a/src/pkg/runtime/memmove_amd64.s b/src/pkg/runtime/memmove_amd64.s
new file mode 100644
index 0000000000..7444d3bdbf
--- /dev/null
+++ b/src/pkg/runtime/memmove_amd64.s
@@ -0,0 +1,65 @@
+	TEXT	memmove(SB), $0
+
+	MOVQ	to+0(FP), DI
+	MOVQ	fr+8(FP), SI
+	MOVLQSX	n+16(FP), BX
+	JLT	fault
+
+/*
+ * check and set for backwards
+ * should we look closer for overlap?
+ */
+	CMPQ	SI, DI
+	JLS	back
+
+/*
+ * foreward copy loop
+ */
+	MOVQ	BX, CX
+	SHRQ	$3, CX
+	ANDQ	$7, BX
+
+	REP;	MOVSQ
+	MOVQ	BX, CX
+	REP;	MOVSB
+
+	MOVQ	to+0(FP),AX
+	RET
+/*
+ * whole thing backwards has
+ * adjusted addresses
+ */
+back:
+	ADDQ	BX, DI
+	ADDQ	BX, SI
+	STD
+
+/*
+ * copy
+ */
+	MOVQ	BX, CX
+	SHRQ	$3, CX
+	ANDQ	$7, BX
+
+	SUBQ	$8, DI
+	SUBQ	$8, SI
+	REP;	MOVSQ
+
+	ADDQ	$7, DI
+	ADDQ	$7, SI
+	MOVQ	BX, CX
+	REP;	MOVSB
+
+	CLD
+	MOVQ	to+0(FP),AX
+	RET
+
+/*
+ * if called with negative count,
+ * treat as error rather than
+ * rotating all of memory
+ */
+fault:
+	MOVQ	$0,SI
+	MOVQ	0(SI), AX
+	RET
diff --git a/src/pkg/runtime/slice.c b/src/pkg/runtime/slice.c
index 722802c004..00d9724fbe 100644
--- a/src/pkg/runtime/slice.c
+++ b/src/pkg/runtime/slice.c
@@ -177,6 +177,39 @@ runtime·arraytoslice(byte* old, uint32 nel, Slice ret)
 	}
 }
 
+// slicecopy(to any, fr any, wid uint32) int
+void
+runtime·slicecopy(Slice to, Slice fm, uintptr width, int32 ret)
+{
+	if(fm.array == nil || fm.len == 0 ||
+	   to.array == nil || to.len == 0 ||
+	   width == 0) {
+		ret = 0;
+		goto out;
+	}
+
+	ret = fm.len;
+	if(to.len > ret)
+		ret = to.len;
+
+	memmove(to.array, fm.array, ret*width);
+
+out:
+	FLUSH(&ret);
+
+	if(debug) {
+		prints("main·copy: to=");
+		runtime·printslice(to);
+		prints("; fm=");
+		runtime·printslice(fm);
+		prints("; width=");
+		runtime·printint(width);
+		prints("; ret=");
+		runtime·printint(ret);
+		prints("\n");
+	}
+}
+
 void
 runtime·printslice(Slice a)
 {