| // 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 |
