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Diffstat (limited to 'src/internal/bytealg/count_arm.s')
-rw-r--r-- | src/internal/bytealg/count_arm.s | 43 |
1 files changed, 43 insertions, 0 deletions
diff --git a/src/internal/bytealg/count_arm.s b/src/internal/bytealg/count_arm.s new file mode 100644 index 0000000..f704ea0 --- /dev/null +++ b/src/internal/bytealg/count_arm.s @@ -0,0 +1,43 @@ +// 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 |