1// Copyright 2019 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#include "go_asm.h"
6#include "textflag.h"
7
8TEXT ·Count(SB),NOSPLIT,$0-20
9	MOVW	b_base+0(FP), R0
10	MOVW	b_len+4(FP), R1
11	MOVBU	c+12(FP), R2
12	MOVW	$ret+16(FP), R7
13	B	countbytebody<>(SB)
14
15TEXT ·CountString(SB),NOSPLIT,$0-16
16	MOVW	s_base+0(FP), R0
17	MOVW	s_len+4(FP), R1
18	MOVBU	c+8(FP), R2
19	MOVW	$ret+12(FP), R7
20	B	countbytebody<>(SB)
21
22// Input:
23// R0: data
24// R1: data length
25// R2: byte to find
26// R7: address to put result
27//
28// On exit:
29// R4 and R8 are clobbered
30TEXT countbytebody<>(SB),NOSPLIT,$0
31	MOVW	$0, R8	// R8 = count of byte to search
32	CMP	$0, R1
33	B.EQ	done	// short path to handle 0-byte case
34	ADD	R0, R1	// R1 is the end of the range
35byte_loop:
36	MOVBU.P	1(R0), R4
37	CMP	R4, R2
38	ADD.EQ	$1, R8
39	CMP	R0, R1
40	B.NE	byte_loop
41done:
42	MOVW	R8, (R7)
43	RET
44