Adding upstream version 1.21.8.upstream/1.21.8

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 204 insertions, 0 deletions

diff --git a/src/runtime/memmove_386.s b/src/runtime/memmove_386.s
new file mode 100644
index 0000000..6d7e17f
--- /dev/null
+++ b/src/runtime/memmove_386.s
@@ -0,0 +1,204 @@
+// Inferno's libkern/memmove-386.s
+// https://bitbucket.org/inferno-os/inferno-os/src/master/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.
+
+//go:build !plan9
+
+#include "go_asm.h"
+#include "textflag.h"
+
+// See memmove Go doc for important implementation constraints.
+
+// func memmove(to, from unsafe.Pointer, n uintptr)
+TEXT runtime·memmove(SB), NOSPLIT, $0-12
+	MOVL	to+0(FP), DI
+	MOVL	from+4(FP), SI
+	MOVL	n+8(FP), BX
+
+	// REP instructions have a high startup cost, so we handle small sizes
+	// with some straightline code. The REP MOVSL instruction is really fast
+	// for large sizes. The cutover is approximately 1K.  We implement up to
+	// 128 because that is the maximum SSE register load (loading all data
+	// into registers lets us ignore copy direction).
+tail:
+	// BSR+branch table make almost all memmove/memclr benchmarks worse. Not worth doing.
+	TESTL	BX, BX
+	JEQ	move_0
+	CMPL	BX, $2
+	JBE	move_1or2
+	CMPL	BX, $4
+	JB	move_3
+	JE	move_4
+	CMPL	BX, $8
+	JBE	move_5through8
+	CMPL	BX, $16
+	JBE	move_9through16
+#ifdef GO386_softfloat
+	JMP	nosse2
+#endif
+	CMPL	BX, $32
+	JBE	move_17through32
+	CMPL	BX, $64
+	JBE	move_33through64
+	CMPL	BX, $128
+	JBE	move_65through128
+
+nosse2:
+/*
+ * check and set for backwards
+ */
+	CMPL	SI, DI
+	JLS	back
+
+/*
+ * forward copy loop
+ */
+forward:
+	// If REP MOVSB isn't fast, don't use it
+	CMPB	internal∕cpu·X86+const_offsetX86HasERMS(SB), $1 // enhanced REP MOVSB/STOSB
+	JNE	fwdBy4
+
+	// Check alignment
+	MOVL	SI, AX
+	ORL	DI, AX
+	TESTL	$3, AX
+	JEQ	fwdBy4
+
+	// Do 1 byte at a time
+	MOVL	BX, CX
+	REP;	MOVSB
+	RET
+
+fwdBy4:
+	// Do 4 bytes at a time
+	MOVL	BX, CX
+	SHRL	$2, CX
+	ANDL	$3, BX
+	REP;	MOVSL
+	JMP	tail
+
+/*
+ * check overlap
+ */
+back:
+	MOVL	SI, CX
+	ADDL	BX, CX
+	CMPL	CX, DI
+	JLS	forward
+/*
+ * whole thing backwards has
+ * adjusted addresses
+ */
+
+	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
+
+	CLD
+	ADDL	$4, DI
+	ADDL	$4, SI
+	SUBL	BX, DI
+	SUBL	BX, SI
+	JMP	tail
+
+move_1or2:
+	MOVB	(SI), AX
+	MOVB	-1(SI)(BX*1), CX
+	MOVB	AX, (DI)
+	MOVB	CX, -1(DI)(BX*1)
+	RET
+move_0:
+	RET
+move_3:
+	MOVW	(SI), AX
+	MOVB	2(SI), CX
+	MOVW	AX, (DI)
+	MOVB	CX, 2(DI)
+	RET
+move_4:
+	// We need a separate case for 4 to make sure we write pointers atomically.
+	MOVL	(SI), AX
+	MOVL	AX, (DI)
+	RET
+move_5through8:
+	MOVL	(SI), AX
+	MOVL	-4(SI)(BX*1), CX
+	MOVL	AX, (DI)
+	MOVL	CX, -4(DI)(BX*1)
+	RET
+move_9through16:
+	MOVL	(SI), AX
+	MOVL	4(SI), CX
+	MOVL	-8(SI)(BX*1), DX
+	MOVL	-4(SI)(BX*1), BP
+	MOVL	AX, (DI)
+	MOVL	CX, 4(DI)
+	MOVL	DX, -8(DI)(BX*1)
+	MOVL	BP, -4(DI)(BX*1)
+	RET
+move_17through32:
+	MOVOU	(SI), X0
+	MOVOU	-16(SI)(BX*1), X1
+	MOVOU	X0, (DI)
+	MOVOU	X1, -16(DI)(BX*1)
+	RET
+move_33through64:
+	MOVOU	(SI), X0
+	MOVOU	16(SI), X1
+	MOVOU	-32(SI)(BX*1), X2
+	MOVOU	-16(SI)(BX*1), X3
+	MOVOU	X0, (DI)
+	MOVOU	X1, 16(DI)
+	MOVOU	X2, -32(DI)(BX*1)
+	MOVOU	X3, -16(DI)(BX*1)
+	RET
+move_65through128:
+	MOVOU	(SI), X0
+	MOVOU	16(SI), X1
+	MOVOU	32(SI), X2
+	MOVOU	48(SI), X3
+	MOVOU	-64(SI)(BX*1), X4
+	MOVOU	-48(SI)(BX*1), X5
+	MOVOU	-32(SI)(BX*1), X6
+	MOVOU	-16(SI)(BX*1), X7
+	MOVOU	X0, (DI)
+	MOVOU	X1, 16(DI)
+	MOVOU	X2, 32(DI)
+	MOVOU	X3, 48(DI)
+	MOVOU	X4, -64(DI)(BX*1)
+	MOVOU	X5, -48(DI)(BX*1)
+	MOVOU	X6, -32(DI)(BX*1)
+	MOVOU	X7, -16(DI)(BX*1)
+	RET