github.com/bir3/gocompiler@v0.9.2202/src/internal/bytealg/equal_riscv64.s (about) 1 // Copyright 2019 The Go Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style 3 // license that can be found in the LICENSE file. 4 5 #include "go_asm.h" 6 #include "textflag.h" 7 8 #define CTXT S10 9 10 // func memequal(a, b unsafe.Pointer, size uintptr) bool 11 TEXT runtime·memequal<ABIInternal>(SB),NOSPLIT|NOFRAME,$0-25 12 // X10 = a_base 13 // X11 = b_base 14 // X12 = size 15 JMP memequal<>(SB) 16 17 // func memequal_varlen(a, b unsafe.Pointer) bool 18 TEXT runtime·memequal_varlen<ABIInternal>(SB),NOSPLIT|NOFRAME,$0-17 19 MOV 8(CTXT), X12 // compiler stores size at offset 8 in the closure 20 // X10 = a_base 21 // X11 = b_base 22 JMP memequal<>(SB) 23 24 // On entry X10 and X11 contain pointers, X12 contains length. 25 // For non-regabi X13 contains address for return value. 26 // For regabi return value in X10. 27 TEXT memequal<>(SB),NOSPLIT|NOFRAME,$0 28 BEQ X10, X11, eq 29 30 MOV $32, X23 31 BLT X12, X23, loop4_check 32 33 // Check alignment - if alignment differs we have to do one byte at a time. 34 AND $7, X10, X9 35 AND $7, X11, X19 36 BNE X9, X19, loop4_check 37 BEQZ X9, loop32_check 38 39 // Check one byte at a time until we reach 8 byte alignment. 40 SUB X9, X0, X9 41 ADD $8, X9, X9 42 SUB X9, X12, X12 43 align: 44 SUB $1, X9 45 MOVBU 0(X10), X19 46 MOVBU 0(X11), X20 47 BNE X19, X20, not_eq 48 ADD $1, X10 49 ADD $1, X11 50 BNEZ X9, align 51 52 loop32_check: 53 MOV $32, X9 54 BLT X12, X9, loop16_check 55 loop32: 56 MOV 0(X10), X19 57 MOV 0(X11), X20 58 MOV 8(X10), X21 59 MOV 8(X11), X22 60 BNE X19, X20, not_eq 61 BNE X21, X22, not_eq 62 MOV 16(X10), X14 63 MOV 16(X11), X15 64 MOV 24(X10), X16 65 MOV 24(X11), X17 66 BNE X14, X15, not_eq 67 BNE X16, X17, not_eq 68 ADD $32, X10 69 ADD $32, X11 70 SUB $32, X12 71 BGE X12, X9, loop32 72 BEQZ X12, eq 73 74 loop16_check: 75 MOV $16, X23 76 BLT X12, X23, loop4_check 77 loop16: 78 MOV 0(X10), X19 79 MOV 0(X11), X20 80 MOV 8(X10), X21 81 MOV 8(X11), X22 82 BNE X19, X20, not_eq 83 BNE X21, X22, not_eq 84 ADD $16, X10 85 ADD $16, X11 86 SUB $16, X12 87 BGE X12, X23, loop16 88 BEQZ X12, eq 89 90 loop4_check: 91 MOV $4, X23 92 BLT X12, X23, loop1 93 loop4: 94 MOVBU 0(X10), X19 95 MOVBU 0(X11), X20 96 MOVBU 1(X10), X21 97 MOVBU 1(X11), X22 98 BNE X19, X20, not_eq 99 BNE X21, X22, not_eq 100 MOVBU 2(X10), X14 101 MOVBU 2(X11), X15 102 MOVBU 3(X10), X16 103 MOVBU 3(X11), X17 104 BNE X14, X15, not_eq 105 BNE X16, X17, not_eq 106 ADD $4, X10 107 ADD $4, X11 108 SUB $4, X12 109 BGE X12, X23, loop4 110 111 loop1: 112 BEQZ X12, eq 113 MOVBU 0(X10), X19 114 MOVBU 0(X11), X20 115 BNE X19, X20, not_eq 116 ADD $1, X10 117 ADD $1, X11 118 SUB $1, X12 119 JMP loop1 120 121 not_eq: 122 MOVB ZERO, X10 123 RET 124 eq: 125 MOV $1, X10 126 RET