Adding upstream version 1.21.8.upstream/1.21.8

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

1 files changed, 126 insertions, 0 deletions

diff --git a/src/internal/bytealg/equal_riscv64.s b/src/internal/bytealg/equal_riscv64.s
new file mode 100644
index 0000000..503aac5
--- /dev/null
+++ b/src/internal/bytealg/equal_riscv64.s
@@ -0,0 +1,126 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "go_asm.h"
+#include "textflag.h"
+
+#define	CTXT	S10
+
+// func memequal(a, b unsafe.Pointer, size uintptr) bool
+TEXT runtime·memequal<ABIInternal>(SB),NOSPLIT|NOFRAME,$0-25
+	// X10 = a_base
+	// X11 = b_base
+	// X12 = size
+	JMP	memequal<>(SB)
+
+// func memequal_varlen(a, b unsafe.Pointer) bool
+TEXT runtime·memequal_varlen<ABIInternal>(SB),NOSPLIT|NOFRAME,$0-17
+	MOV	8(CTXT), X12    // compiler stores size at offset 8 in the closure
+	// X10 = a_base
+	// X11 = b_base
+	JMP	memequal<>(SB)
+
+// On entry X10 and X11 contain pointers, X12 contains length.
+// For non-regabi X13 contains address for return value.
+// For regabi return value in X10.
+TEXT memequal<>(SB),NOSPLIT|NOFRAME,$0
+	BEQ	X10, X11, eq
+
+	MOV	$32, X23
+	BLT	X12, X23, loop4_check
+
+	// Check alignment - if alignment differs we have to do one byte at a time.
+	AND	$7, X10, X9
+	AND	$7, X11, X19
+	BNE	X9, X19, loop4_check
+	BEQZ	X9, loop32_check
+
+	// Check one byte at a time until we reach 8 byte alignment.
+	SUB	X9, X0, X9
+	ADD	$8, X9, X9
+	SUB	X9, X12, X12
+align:
+	ADD	$-1, X9
+	MOVBU	0(X10), X19
+	MOVBU	0(X11), X20
+	BNE	X19, X20, not_eq
+	ADD	$1, X10
+	ADD	$1, X11
+	BNEZ	X9, align
+
+loop32_check:
+	MOV	$32, X9
+	BLT	X12, X9, loop16_check
+loop32:
+	MOV	0(X10), X19
+	MOV	0(X11), X20
+	MOV	8(X10), X21
+	MOV	8(X11), X22
+	BNE	X19, X20, not_eq
+	BNE	X21, X22, not_eq
+	MOV	16(X10), X14
+	MOV	16(X11), X15
+	MOV	24(X10), X16
+	MOV	24(X11), X17
+	BNE	X14, X15, not_eq
+	BNE	X16, X17, not_eq
+	ADD	$32, X10
+	ADD	$32, X11
+	ADD	$-32, X12
+	BGE	X12, X9, loop32
+	BEQZ	X12, eq
+
+loop16_check:
+	MOV	$16, X23
+	BLT	X12, X23, loop4_check
+loop16:
+	MOV	0(X10), X19
+	MOV	0(X11), X20
+	MOV	8(X10), X21
+	MOV	8(X11), X22
+	BNE	X19, X20, not_eq
+	BNE	X21, X22, not_eq
+	ADD	$16, X10
+	ADD	$16, X11
+	ADD	$-16, X12
+	BGE	X12, X23, loop16
+	BEQZ	X12, eq
+
+loop4_check:
+	MOV	$4, X23
+	BLT	X12, X23, loop1
+loop4:
+	MOVBU	0(X10), X19
+	MOVBU	0(X11), X20
+	MOVBU	1(X10), X21
+	MOVBU	1(X11), X22
+	BNE	X19, X20, not_eq
+	BNE	X21, X22, not_eq
+	MOVBU	2(X10), X14
+	MOVBU	2(X11), X15
+	MOVBU	3(X10), X16
+	MOVBU	3(X11), X17
+	BNE	X14, X15, not_eq
+	BNE	X16, X17, not_eq
+	ADD	$4, X10
+	ADD	$4, X11
+	ADD	$-4, X12
+	BGE	X12, X23, loop4
+
+loop1:
+	BEQZ	X12, eq
+	MOVBU	0(X10), X19
+	MOVBU	0(X11), X20
+	BNE	X19, X20, not_eq
+	ADD	$1, X10
+	ADD	$1, X11
+	ADD	$-1, X12
+	JMP	loop1
+
+not_eq:
+	MOVB	ZERO, X10
+	RET
+eq:
+	MOV	$1, X10
+	RET