| | // 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. |
| |
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| | TEXT 路Compare<ABIInternal>(SB),NOSPLIT|NOFRAME,$0-56 |
| | // R0 = a_base (want in R0) |
| | // R1 = a_len (want in R1) |
| | // R2 = a_cap (unused) |
| | // R3 = b_base (want in R2) |
| | // R4 = b_len (want in R3) |
| | // R5 = b_cap (unused) |
| | MOVD R3, R2 |
| | MOVD R4, R3 |
| | B cmpbody<>(SB) |
| |
|
| | TEXT runtime路cmpstring<ABIInternal>(SB),NOSPLIT|NOFRAME,$0-40 |
| | // R0 = a_base |
| | // R1 = a_len |
| | // R2 = b_base |
| | // R3 = b_len |
| | B cmpbody<>(SB) |
| |
|
| | // On entry: |
| | // R0 points to the start of a |
| | // R1 is the length of a |
| | // R2 points to the start of b |
| | // R3 is the length of b |
| | // |
| | // On exit: |
| | // R0 is the result |
| | // R4, R5, R6, R8, R9 and R10 are clobbered |
| | TEXT cmpbody<>(SB),NOSPLIT|NOFRAME,$0-0 |
| | CMP R0, R2 |
| | BEQ samebytes // same starting pointers; compare lengths |
| | CMP R1, R3 |
| | CSEL LT, R3, R1, R6 // R6 is min(R1, R3) |
| |
|
| | CBZ R6, samebytes |
| | BIC $0xf, R6, R10 |
| | CBZ R10, small // length < 16 |
| | ADD R0, R10 // end of chunk16 |
| | // length >= 16 |
| | chunk16_loop: |
| | LDP.P 16(R0), (R4, R8) |
| | LDP.P 16(R2), (R5, R9) |
| | CMP R4, R5 |
| | BNE cmp |
| | CMP R8, R9 |
| | BNE cmpnext |
| | CMP R10, R0 |
| | BNE chunk16_loop |
| | AND $0xf, R6, R6 |
| | CBZ R6, samebytes |
| | SUBS $8, R6 |
| | BLT tail |
| | // the length of tail > 8 bytes |
| | MOVD.P 8(R0), R4 |
| | MOVD.P 8(R2), R5 |
| | CMP R4, R5 |
| | BNE cmp |
| | SUB $8, R6 |
| | // compare last 8 bytes |
| | tail: |
| | MOVD (R0)(R6), R4 |
| | MOVD (R2)(R6), R5 |
| | CMP R4, R5 |
| | BEQ samebytes |
| | cmp: |
| | REV R4, R4 |
| | REV R5, R5 |
| | CMP R4, R5 |
| | ret: |
| | MOVD $1, R0 |
| | CNEG HI, R0, R0 |
| | RET |
| | small: |
| | TBZ $3, R6, lt_8 |
| | MOVD (R0), R4 |
| | MOVD (R2), R5 |
| | CMP R4, R5 |
| | BNE cmp |
| | SUBS $8, R6 |
| | BEQ samebytes |
| | ADD $8, R0 |
| | ADD $8, R2 |
| | SUB $8, R6 |
| | B tail |
| | lt_8: |
| | TBZ $2, R6, lt_4 |
| | MOVWU (R0), R4 |
| | MOVWU (R2), R5 |
| | CMPW R4, R5 |
| | BNE cmp |
| | SUBS $4, R6 |
| | BEQ samebytes |
| | ADD $4, R0 |
| | ADD $4, R2 |
| | lt_4: |
| | TBZ $1, R6, lt_2 |
| | MOVHU (R0), R4 |
| | MOVHU (R2), R5 |
| | CMPW R4, R5 |
| | BNE cmp |
| | ADD $2, R0 |
| | ADD $2, R2 |
| | lt_2: |
| | TBZ $0, R6, samebytes |
| | one: |
| | MOVBU (R0), R4 |
| | MOVBU (R2), R5 |
| | CMPW R4, R5 |
| | BNE ret |
| | samebytes: |
| | CMP R3, R1 |
| | CSET NE, R0 |
| | CNEG LO, R0, R0 |
| | RET |
| | cmpnext: |
| | REV R8, R4 |
| | REV R9, R5 |
| | CMP R4, R5 |
| | B ret |
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