copy tweaks

  * move memmove to arch-specific subdirectories
  * add memmove for arm
  * add copyright notices marking them as copied from Inferno

R=ken2
https://golang.org/cl/156061

1 files changed, 90 insertions, 0 deletions

diff --git a/src/pkg/runtime/amd64/memmove.s b/src/pkg/runtime/amd64/memmove.s
new file mode 100644
index 0000000000..e0a03d6def
--- /dev/null
+++ b/src/pkg/runtime/amd64/memmove.s
@@ -0,0 +1,90 @@
+// Derived from Inferno's libkern/memmove-386.s (adapted for amd64)
+// http://code.google.com/p/inferno-os/source/browse/libkern/memmove-386.s
+//
+//         Copyright © 1994-1999 Lucent Technologies Inc.  All rights reserved.
+//         Revisions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com).  All rights reserved.
+//         Portions Copyright 2009 The Go Authors. All rights reserved.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+	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