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Diffstat (limited to 'src/internal/bytealg/compare_wasm.s')
| -rw-r--r-- | src/internal/bytealg/compare_wasm.s | 115 |
1 files changed, 115 insertions, 0 deletions
diff --git a/src/internal/bytealg/compare_wasm.s b/src/internal/bytealg/compare_wasm.s new file mode 100644 index 0000000..dc8fb33 --- /dev/null +++ b/src/internal/bytealg/compare_wasm.s @@ -0,0 +1,115 @@ +// 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 ·Compare(SB), NOSPLIT, $0-56 + Get SP + I64Load a_base+0(FP) + I64Load a_len+8(FP) + I64Load b_base+24(FP) + I64Load b_len+32(FP) + Call cmpbody<>(SB) + I64Store ret+48(FP) + RET + +TEXT runtime·cmpstring(SB), NOSPLIT, $0-40 + Get SP + I64Load a_base+0(FP) + I64Load a_len+8(FP) + I64Load b_base+16(FP) + I64Load b_len+24(FP) + Call cmpbody<>(SB) + I64Store ret+32(FP) + RET + +// params: a, alen, b, blen +// ret: -1/0/1 +TEXT cmpbody<>(SB), NOSPLIT, $0-0 + // len = min(alen, blen) + Get R1 + Get R3 + Get R1 + Get R3 + I64LtU + Select + Set R4 + + Get R0 + I32WrapI64 + Get R2 + I32WrapI64 + Get R4 + I32WrapI64 + Call memcmp<>(SB) + I64ExtendI32S + Tee R5 + + I64Eqz + If + // check length + Get R1 + Get R3 + I64Sub + Set R5 + End + + I64Const $0 + I64Const $-1 + I64Const $1 + Get R5 + I64Const $0 + I64LtS + Select + Get R5 + I64Eqz + Select + Return + +// compiled with emscripten +// params: a, b, len +// ret: <0/0/>0 +TEXT memcmp<>(SB), NOSPLIT, $0-0 + Get R2 + If $1 + Loop + Get R0 + I32Load8S $0 + Tee R3 + Get R1 + I32Load8S $0 + Tee R4 + I32Eq + If + Get R0 + I32Const $1 + I32Add + Set R0 + Get R1 + I32Const $1 + I32Add + Set R1 + I32Const $0 + Get R2 + I32Const $-1 + I32Add + Tee R2 + I32Eqz + BrIf $3 + Drop + Br $1 + End + End + Get R3 + I32Const $255 + I32And + Get R4 + I32Const $255 + I32And + I32Sub + Else + I32Const $0 + End + Return |