ref: a2be120ea93ae67447315da268fa336650cd5149
dir: /sys/src/9/alphapc/memmove.s/
#define QUAD 8 #define ALIGN 64 #define BLOCK 64 TEXT memmove(SB), $0 MOVL from+4(FP), R7 MOVL n+8(FP), R10 MOVQ R0, R6 CMPUGE R7, R0, R5 BNE R5, _forward MOVQ R6, R8 /* end to address */ ADDL R10, R6, R6 /* to+n */ ADDL R10, R7, R7 /* from+n */ CMPUGE $ALIGN, R10, R1 /* need at least ALIGN bytes */ BNE R1, _b1tail _balign: AND $(ALIGN-1), R6, R1 BEQ R1, _baligned MOVBU -1(R7), R2 ADDL $-1, R6, R6 MOVB R2, (R6) ADDL $-1, R7, R7 JMP _balign _baligned: AND $(QUAD-1), R7, R1 /* is the source quad-aligned */ BNE R1, _bunaligned ADDL $(BLOCK-1), R8, R9 _bblock: CMPUGE R9, R6, R1 BNE R1, _b8tail MOVQ -64(R7), R22 MOVQ -56(R7), R23 MOVQ -48(R7), R24 MOVQ -40(R7), R25 MOVQ -32(R7), R2 MOVQ -24(R7), R3 MOVQ -16(R7), R4 MOVQ -8(R7), R5 SUBL $64, R6, R6 SUBL $64, R7, R7 MOVQ R22, (R6) MOVQ R23, 8(R6) MOVQ R24, 16(R6) MOVQ R25, 24(R6) MOVQ R2, 32(R6) MOVQ R3, 40(R6) MOVQ R4, 48(R6) MOVQ R5, 56(R6) JMP _bblock _b8tail: ADDL $(QUAD-1), R8, R9 _b8block: CMPUGE R9, R6, R1 BNE R1, _b1tail MOVQ -8(R7), R2 SUBL $8, R6 MOVQ R2, (R6) SUBL $8, R7 JMP _b8block _b1tail: CMPUGE R8, R6, R1 BNE R1, _ret MOVBU -1(R7), R2 SUBL $1, R6, R6 MOVB R2, (R6) SUBL $1, R7, R7 JMP _b1tail _ret: RET _bunaligned: ADDL $(16-1), R8, R9 _bu8block: CMPUGE R9, R6, R1 BNE R1, _b1tail MOVQU -16(R7), R4 MOVQU -8(R7), R3 MOVQU (R7), R2 SUBL $16, R6 EXTQH R7, R2, R2 EXTQL R7, R3, R5 OR R5, R2, R11 EXTQH R7, R3, R3 EXTQL R7, R4, R4 OR R3, R4, R13 MOVQ R11, 8(R6) MOVQ R13, (R6) SUBL $16, R7 JMP _bu8block _forward: ADDL R10, R6, R8 /* end to address */ CMPUGE $ALIGN, R10, R1 /* need at least ALIGN bytes */ BNE R1, _f1tail _falign: AND $(ALIGN-1), R6, R1 BEQ R1, _faligned MOVBU (R7), R2 ADDL $1, R6, R6 ADDL $1, R7, R7 MOVB R2, -1(R6) JMP _falign _faligned: AND $(QUAD-1), R7, R1 /* is the source quad-aligned */ BNE R1, _funaligned SUBL $(BLOCK-1), R8, R9 _fblock: CMPUGT R9, R6, R1 BEQ R1, _f8tail MOVQ (R7), R2 MOVQ 8(R7), R3 MOVQ 16(R7), R4 MOVQ 24(R7), R5 MOVQ 32(R7), R22 MOVQ 40(R7), R23 MOVQ 48(R7), R24 MOVQ 56(R7), R25 ADDL $64, R6, R6 ADDL $64, R7, R7 MOVQ R2, -64(R6) MOVQ R3, -56(R6) MOVQ R4, -48(R6) MOVQ R5, -40(R6) MOVQ R22, -32(R6) MOVQ R23, -24(R6) MOVQ R24, -16(R6) MOVQ R25, -8(R6) JMP _fblock _f8tail: SUBL $(QUAD-1), R8, R9 _f8block: CMPUGT R9, R6, R1 BEQ R1, _f1tail MOVQ (R7), R2 ADDL $8, R6 ADDL $8, R7 MOVQ R2, -8(R6) JMP _f8block _f1tail: CMPUGT R8, R6, R1 BEQ R1, _fret MOVBU (R7), R2 ADDL $1, R6, R6 ADDL $1, R7, R7 MOVB R2, -1(R6) JMP _f1tail _fret: RET _funaligned: SUBL $(16-1), R8, R9 _fu8block: CMPUGT R9, R6, R1 BEQ R1, _f1tail MOVQU (R7), R2 MOVQU 8(R7), R3 MOVQU 16(R7), R4 EXTQL R7, R2, R2 EXTQH R7, R3, R5 OR R5, R2, R11 EXTQL R7, R3, R3 MOVQ R11, (R6) EXTQH R7, R4, R4 OR R3, R4, R11 MOVQ R11, 8(R6) ADDL $16, R6 ADDL $16, R7 JMP _fu8block