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Diffstat (limited to 'src/runtime/memmove_mipsx.s')
| -rw-r--r-- | src/runtime/memmove_mipsx.s | 260 |
1 files changed, 260 insertions, 0 deletions
diff --git a/src/runtime/memmove_mipsx.s b/src/runtime/memmove_mipsx.s new file mode 100644 index 0000000..494288c --- /dev/null +++ b/src/runtime/memmove_mipsx.s @@ -0,0 +1,260 @@ +// Copyright 2016 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 mips || mipsle + +#include "textflag.h" + +#ifdef GOARCH_mips +#define MOVWHI MOVWL +#define MOVWLO MOVWR +#else +#define MOVWHI MOVWR +#define MOVWLO MOVWL +#endif + +// See memmove Go doc for important implementation constraints. + +// func memmove(to, from unsafe.Pointer, n uintptr) +TEXT runtime·memmove(SB),NOSPLIT,$-0-12 + MOVW n+8(FP), R3 + MOVW from+4(FP), R2 + MOVW to+0(FP), R1 + + ADDU R3, R2, R4 // end pointer for source + ADDU R3, R1, R5 // end pointer for destination + + // if destination is ahead of source, start at the end of the buffer and go backward. + SGTU R1, R2, R6 + BNE R6, backward + + // if less than 4 bytes, use byte by byte copying + SGTU $4, R3, R6 + BNE R6, f_small_copy + + // align destination to 4 bytes + AND $3, R1, R6 + BEQ R6, f_dest_aligned + SUBU R1, R0, R6 + AND $3, R6 + MOVWHI 0(R2), R7 + SUBU R6, R3 + MOVWLO 3(R2), R7 + ADDU R6, R2 + MOVWHI R7, 0(R1) + ADDU R6, R1 + +f_dest_aligned: + AND $31, R3, R7 + AND $3, R3, R6 + SUBU R7, R5, R7 // end pointer for 32-byte chunks + SUBU R6, R5, R6 // end pointer for 4-byte chunks + + // if source is not aligned, use unaligned reads + AND $3, R2, R8 + BNE R8, f_large_ua + +f_large: + BEQ R1, R7, f_words + ADDU $32, R1 + MOVW 0(R2), R8 + MOVW 4(R2), R9 + MOVW 8(R2), R10 + MOVW 12(R2), R11 + MOVW 16(R2), R12 + MOVW 20(R2), R13 + MOVW 24(R2), R14 + MOVW 28(R2), R15 + ADDU $32, R2 + MOVW R8, -32(R1) + MOVW R9, -28(R1) + MOVW R10, -24(R1) + MOVW R11, -20(R1) + MOVW R12, -16(R1) + MOVW R13, -12(R1) + MOVW R14, -8(R1) + MOVW R15, -4(R1) + JMP f_large + +f_words: + BEQ R1, R6, f_tail + ADDU $4, R1 + MOVW 0(R2), R8 + ADDU $4, R2 + MOVW R8, -4(R1) + JMP f_words + +f_tail: + BEQ R1, R5, ret + MOVWLO -1(R4), R8 + MOVWLO R8, -1(R5) + +ret: + RET + +f_large_ua: + BEQ R1, R7, f_words_ua + ADDU $32, R1 + MOVWHI 0(R2), R8 + MOVWHI 4(R2), R9 + MOVWHI 8(R2), R10 + MOVWHI 12(R2), R11 + MOVWHI 16(R2), R12 + MOVWHI 20(R2), R13 + MOVWHI 24(R2), R14 + MOVWHI 28(R2), R15 + MOVWLO 3(R2), R8 + MOVWLO 7(R2), R9 + MOVWLO 11(R2), R10 + MOVWLO 15(R2), R11 + MOVWLO 19(R2), R12 + MOVWLO 23(R2), R13 + MOVWLO 27(R2), R14 + MOVWLO 31(R2), R15 + ADDU $32, R2 + MOVW R8, -32(R1) + MOVW R9, -28(R1) + MOVW R10, -24(R1) + MOVW R11, -20(R1) + MOVW R12, -16(R1) + MOVW R13, -12(R1) + MOVW R14, -8(R1) + MOVW R15, -4(R1) + JMP f_large_ua + +f_words_ua: + BEQ R1, R6, f_tail_ua + MOVWHI 0(R2), R8 + ADDU $4, R1 + MOVWLO 3(R2), R8 + ADDU $4, R2 + MOVW R8, -4(R1) + JMP f_words_ua + +f_tail_ua: + BEQ R1, R5, ret + MOVWHI -4(R4), R8 + MOVWLO -1(R4), R8 + MOVWLO R8, -1(R5) + JMP ret + +f_small_copy: + BEQ R1, R5, ret + ADDU $1, R1 + MOVB 0(R2), R6 + ADDU $1, R2 + MOVB R6, -1(R1) + JMP f_small_copy + +backward: + SGTU $4, R3, R6 + BNE R6, b_small_copy + + AND $3, R5, R6 + BEQ R6, b_dest_aligned + MOVWHI -4(R4), R7 + SUBU R6, R3 + MOVWLO -1(R4), R7 + SUBU R6, R4 + MOVWLO R7, -1(R5) + SUBU R6, R5 + +b_dest_aligned: + AND $31, R3, R7 + AND $3, R3, R6 + ADDU R7, R1, R7 + ADDU R6, R1, R6 + + AND $3, R4, R8 + BNE R8, b_large_ua + +b_large: + BEQ R5, R7, b_words + ADDU $-32, R5 + MOVW -4(R4), R8 + MOVW -8(R4), R9 + MOVW -12(R4), R10 + MOVW -16(R4), R11 + MOVW -20(R4), R12 + MOVW -24(R4), R13 + MOVW -28(R4), R14 + MOVW -32(R4), R15 + ADDU $-32, R4 + MOVW R8, 28(R5) + MOVW R9, 24(R5) + MOVW R10, 20(R5) + MOVW R11, 16(R5) + MOVW R12, 12(R5) + MOVW R13, 8(R5) + MOVW R14, 4(R5) + MOVW R15, 0(R5) + JMP b_large + +b_words: + BEQ R5, R6, b_tail + ADDU $-4, R5 + MOVW -4(R4), R8 + ADDU $-4, R4 + MOVW R8, 0(R5) + JMP b_words + +b_tail: + BEQ R5, R1, ret + MOVWHI 0(R2), R8 // R2 and R1 have the same alignment so we don't need to load a whole word + MOVWHI R8, 0(R1) + JMP ret + +b_large_ua: + BEQ R5, R7, b_words_ua + ADDU $-32, R5 + MOVWHI -4(R4), R8 + MOVWHI -8(R4), R9 + MOVWHI -12(R4), R10 + MOVWHI -16(R4), R11 + MOVWHI -20(R4), R12 + MOVWHI -24(R4), R13 + MOVWHI -28(R4), R14 + MOVWHI -32(R4), R15 + MOVWLO -1(R4), R8 + MOVWLO -5(R4), R9 + MOVWLO -9(R4), R10 + MOVWLO -13(R4), R11 + MOVWLO -17(R4), R12 + MOVWLO -21(R4), R13 + MOVWLO -25(R4), R14 + MOVWLO -29(R4), R15 + ADDU $-32, R4 + MOVW R8, 28(R5) + MOVW R9, 24(R5) + MOVW R10, 20(R5) + MOVW R11, 16(R5) + MOVW R12, 12(R5) + MOVW R13, 8(R5) + MOVW R14, 4(R5) + MOVW R15, 0(R5) + JMP b_large_ua + +b_words_ua: + BEQ R5, R6, b_tail_ua + MOVWHI -4(R4), R8 + ADDU $-4, R5 + MOVWLO -1(R4), R8 + ADDU $-4, R4 + MOVW R8, 0(R5) + JMP b_words_ua + +b_tail_ua: + BEQ R5, R1, ret + MOVWHI (R2), R8 + MOVWLO 3(R2), R8 + MOVWHI R8, 0(R1) + JMP ret + +b_small_copy: + BEQ R5, R1, ret + ADDU $-1, R5 + MOVB -1(R4), R6 + ADDU $-1, R4 + MOVB R6, 0(R5) + JMP b_small_copy |