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// 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"
TEXT ·Count(SB),NOSPLIT,$0-20
MOVW b_base+0(FP), R0
MOVW b_len+4(FP), R1
MOVBU c+12(FP), R2
MOVW $ret+16(FP), R7
B countbytebody<>(SB)
TEXT ·CountString(SB),NOSPLIT,$0-16
MOVW s_base+0(FP), R0
MOVW s_len+4(FP), R1
MOVBU c+8(FP), R2
MOVW $ret+12(FP), R7
B countbytebody<>(SB)
// Input:
// R0: data
// R1: data length
// R2: byte to find
// R7: address to put result
//
// On exit:
// R4 and R8 are clobbered
TEXT countbytebody<>(SB),NOSPLIT,$0
MOVW $0, R8 // R8 = count of byte to search
CMP $0, R1
B.EQ done // short path to handle 0-byte case
ADD R0, R1 // R1 is the end of the range
byte_loop:
MOVBU.P 1(R0), R4
CMP R4, R2
ADD.EQ $1, R8
CMP R0, R1
B.NE byte_loop
done:
MOVW R8, (R7)
RET
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