1// Copyright 2015 The Go Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style
3// license that can be found in the LICENSE file.
4
5//go:build mips64 || mips64le
6
7#include "go_asm.h"
8#include "textflag.h"
9
10// See memclrNoHeapPointers Go doc for important implementation constraints.
11
12// func memclrNoHeapPointers(ptr unsafe.Pointer, n uintptr)
13TEXT runtime·memclrNoHeapPointers(SB),NOSPLIT,$0-16
14	MOVV	ptr+0(FP), R1
15	MOVV	n+8(FP), R2
16	ADDV	R1, R2, R4
17
18	// if less than 16 bytes or no MSA, do words check
19	SGTU	$16, R2, R3
20	BNE	R3, no_msa
21	MOVBU	internal∕cpu·MIPS64X+const_offsetMIPS64XHasMSA(SB), R3
22	BEQ	R3, R0, no_msa
23
24	VMOVB	$0, W0
25
26	SGTU	$128, R2, R3
27	BEQ	R3, msa_large
28
29	AND	$15, R2, R5
30	XOR	R2, R5, R6
31	ADDVU	R1, R6
32
33msa_small:
34	VMOVB	W0, (R1)
35	ADDVU	$16, R1
36	SGTU	R6, R1, R3
37	BNE	R3, R0, msa_small
38	BEQ	R5, R0, done
39	VMOVB	W0, -16(R4)
40	JMP	done
41
42msa_large:
43	AND	$127, R2, R5
44	XOR	R2, R5, R6
45	ADDVU	R1, R6
46
47msa_large_loop:
48	VMOVB	W0, (R1)
49	VMOVB	W0, 16(R1)
50	VMOVB	W0, 32(R1)
51	VMOVB	W0, 48(R1)
52	VMOVB	W0, 64(R1)
53	VMOVB	W0, 80(R1)
54	VMOVB	W0, 96(R1)
55	VMOVB	W0, 112(R1)
56
57	ADDVU	$128, R1
58	SGTU	R6, R1, R3
59	BNE	R3, R0, msa_large_loop
60	BEQ	R5, R0, done
61	VMOVB	W0, -128(R4)
62	VMOVB	W0, -112(R4)
63	VMOVB	W0, -96(R4)
64	VMOVB	W0, -80(R4)
65	VMOVB	W0, -64(R4)
66	VMOVB	W0, -48(R4)
67	VMOVB	W0, -32(R4)
68	VMOVB	W0, -16(R4)
69	JMP	done
70
71no_msa:
72	// if less than 8 bytes, do one byte at a time
73	SGTU	$8, R2, R3
74	BNE	R3, out
75
76	// do one byte at a time until 8-aligned
77	AND	$7, R1, R3
78	BEQ	R3, words
79	MOVB	R0, (R1)
80	ADDV	$1, R1
81	JMP	-4(PC)
82
83words:
84	// do 8 bytes at a time if there is room
85	ADDV	$-7, R4, R2
86
87	SGTU	R2, R1, R3
88	BEQ	R3, out
89	MOVV	R0, (R1)
90	ADDV	$8, R1
91	JMP	-4(PC)
92
93out:
94	BEQ	R1, R4, done
95	MOVB	R0, (R1)
96	ADDV	$1, R1
97	JMP	-3(PC)
98done:
99	RET
100