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-rw-r--r--src/internal/bytealg/indexbyte_arm.s46
1 files changed, 46 insertions, 0 deletions
diff --git a/src/internal/bytealg/indexbyte_arm.s b/src/internal/bytealg/indexbyte_arm.s
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+// Copyright 2018 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 ·IndexByte(SB),NOSPLIT,$0-20
+ MOVW b_base+0(FP), R0
+ MOVW b_len+4(FP), R1
+ MOVBU c+12(FP), R2 // byte to find
+ MOVW $ret+16(FP), R5
+ B indexbytebody<>(SB)
+
+TEXT ·IndexByteString(SB),NOSPLIT,$0-16
+ MOVW s_base+0(FP), R0
+ MOVW s_len+4(FP), R1
+ MOVBU c+8(FP), R2 // byte to find
+ MOVW $ret+12(FP), R5
+ B indexbytebody<>(SB)
+
+// input:
+// R0: data
+// R1: data length
+// R2: byte to find
+// R5: address to put result
+TEXT indexbytebody<>(SB),NOSPLIT,$0-0
+ MOVW R0, R4 // store base for later
+ ADD R0, R1 // end
+
+loop:
+ CMP R0, R1
+ B.EQ notfound
+ MOVBU.P 1(R0), R3
+ CMP R2, R3
+ B.NE loop
+
+ SUB $1, R0 // R0 will be one beyond the position we want
+ SUB R4, R0 // remove base
+ MOVW R0, (R5)
+ RET
+
+notfound:
+ MOVW $-1, R0
+ MOVW R0, (R5)
+ RET