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Diffstat (limited to '')
-rw-r--r-- | src/internal/bytealg/compare_mips64x.s | 89 |
1 files changed, 89 insertions, 0 deletions
diff --git a/src/internal/bytealg/compare_mips64x.s b/src/internal/bytealg/compare_mips64x.s new file mode 100644 index 0000000..b472e51 --- /dev/null +++ b/src/internal/bytealg/compare_mips64x.s @@ -0,0 +1,89 @@ +// 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. + +//go:build mips64 || mips64le +// +build mips64 mips64le + +#include "go_asm.h" +#include "textflag.h" + +TEXT ·Compare(SB),NOSPLIT,$0-56 + MOVV a_base+0(FP), R3 + MOVV b_base+24(FP), R4 + MOVV a_len+8(FP), R1 + MOVV b_len+32(FP), R2 + MOVV $ret+48(FP), R9 + JMP cmpbody<>(SB) + +TEXT runtime·cmpstring(SB),NOSPLIT,$0-40 + MOVV a_base+0(FP), R3 + MOVV b_base+16(FP), R4 + MOVV a_len+8(FP), R1 + MOVV b_len+24(FP), R2 + MOVV $ret+32(FP), R9 + JMP cmpbody<>(SB) + +// On entry: +// R1 length of a +// R2 length of b +// R3 points to the start of a +// R4 points to the start of b +// R9 points to the return value (-1/0/1) +TEXT cmpbody<>(SB),NOSPLIT|NOFRAME,$0 + BEQ R3, R4, samebytes // same start of a and b + + SGTU R1, R2, R7 + BNE R0, R7, r2_lt_r1 + MOVV R1, R10 + JMP entry +r2_lt_r1: + MOVV R2, R10 // R10 is min(R1, R2) +entry: + ADDV R3, R10, R8 // R3 start of a, R8 end of a + BEQ R3, R8, samebytes // length is 0 + + SRLV $4, R10 // R10 is number of chunks + BEQ R0, R10, byte_loop + + // make sure both a and b are aligned. + OR R3, R4, R11 + AND $7, R11 + BNE R0, R11, byte_loop + +chunk16_loop: + BEQ R0, R10, byte_loop + MOVV (R3), R6 + MOVV (R4), R7 + BNE R6, R7, byte_loop + MOVV 8(R3), R13 + MOVV 8(R4), R14 + ADDV $16, R3 + ADDV $16, R4 + SUBVU $1, R10 + BEQ R13, R14, chunk16_loop + SUBV $8, R3 + SUBV $8, R4 + +byte_loop: + BEQ R3, R8, samebytes + MOVBU (R3), R6 + ADDVU $1, R3 + MOVBU (R4), R7 + ADDVU $1, R4 + BEQ R6, R7, byte_loop + +byte_cmp: + SGTU R6, R7, R8 // R8 = 1 if (R6 > R7) + BNE R0, R8, ret + MOVV $-1, R8 + JMP ret + +samebytes: + SGTU R1, R2, R6 + SGTU R2, R1, R7 + SUBV R7, R6, R8 + +ret: + MOVV R8, (R9) + RET |