Mega Code Archive

Split a string very fast using delimiters [function] [part2]

// after optimizations with delphi it comes a // time for some assembler; also the memory // management (slow result allocation) has been // taken care of... // note : You MUST have the following global // variables : // var // Splitresult : Array[0..1023] of Char; // P_SplitResArray : Pointer; // then on form1.create assign Pointer : // P_SplitResArray := @SplitResult; // variable Splitresult will contain // the result after procedure has been completed procedure split5(const input: string; schar: Char; s: Byte); register; asm PUSH ECX PUSH EAX //registers : PUSH EDX //EAX = input PUSH EDI //DH = s TEST EAX, EAX //if input = '' then JZ @NoWords // goto @NoInput @WeHaveIt:MOV DH, CL //DL = schar MOV EDI, EAX //EDI := Addr(input); MOV ECX, [EDI-4] //ECX := length(input); @GoGo: MOV AL, DL //AL := Schar; CMP DH, 2 //IF DH = 2 then JE @StartCo // goto @StartCo MOV AH, 2 //AH (upper 8 bits of AX) will be our separator counter initial value is 2, max 256 @Lop: INC AH //AH := AH + 1 REPNE SCASB //while (EDI^<>AL) and (ECX>0) begin INC EDI; DEC ECX; end; CMP AH, DH //if AH < DH then JB @Lop // goto @Lop TEST ECX, ECX //IF ECX > 0 then JG @StartCo // goto @StartCp @NoWords: MOV EDI,[P_SplitResArray] //result := MOV BYTE PTR [EDI], $0 // '' JMP @TotalEnd @StartCo: PUSH ESI MOV ESI, EDI MOV EDI, [P_SplitResArray] @CopyLoop:MOV AH, BYTE PTR[ESI+0] //32 bit aligned loop.. hopefully :) CMP AH, DL //1. test, 8 bits JE @Endword MOV BYTE PTR [EDI+0], AH INC EDI MOV AH, BYTE PTR[ESI+1] CMP AH, DL //2. test, 8 bits -> 16 bits.. JE @Endword MOV BYTE PTR [EDI+0], AH INC EDI MOV AH, BYTE PTR[ESI+2] CMP AH, DL //3. test, 8 bits -> 24 bits.. JE @Endword MOV BYTE PTR [EDI+0], AH INC EDI MOV AH, BYTE PTR[ESI+3] CMP AH, DL //4. test, 8 bits -> 32 bits.. JE @Endword MOV BYTE PTR [EDI+0], AH INC EDI ADD ESI, 4 SUB ECX, 4 CMP ECX, 0 JG @Copyloop @EndWord: MOV BYTE PTR [EDI], $0 //lisää nolla POP ESI @TotalEnd:POP EDI POP EDX POP EAX POP ECX @Final: RET