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function SmartPosAsm(const substr : AnsiString;

 const s : AnsiString; StartPos : Cardinal) : Integer;

type

  StrRec = packed record

    allocSiz: Longint;

    refCnt: Longint;

    length: Longint;

  end;

const

  skew = sizeof(StrRec);

asm

{     ->EAX     Pointer to substr               }

{       EDX     Pointer to string               }

{     <-EAX     Position of substr in s or 0    }

        TEST    EAX,EAX

        JE      @@noWork

        TEST    EDX,EDX

        JE      @@stringEmpty

        PUSH    EBX

        PUSH    ESI

        PUSH    EDI

        MOV     ESI,EAX         { Point ESI to substr           }

        MOV     EDI,EDX         { Point EDI to s                }

        MOV     EAX,ECX

        MOV     ECX,[EDI-skew].StrRec.length  { ECX = Length(s) }

        ADD     EDI,EAX

        SUB     ECX,EAX

        PUSH    EDI  { remember s position to calculate index     }

        MOV     EDX,[ESI-skew].StrRec.length { EDX = Length(substr)

        DEC     EDX              { EDX = Length(substr) - 1    }

        JS      @@fail           { < 0 ? return 0              }

        MOV     AL,[ESI]         { AL = first char of substr   }

        INC     ESI          { Point ESI to 2'nd char of substr}

        SUB     ECX,EDX       { #positions in s to look at    }

                      { = Length(s) - Length(substr) + 1      }

        JLE     @@fail

@@loop:

        REPNE   SCASB

        JNE     @@fail

        MOV     EBX,ECX          { save outer loop counter    }

        PUSH    ESI              { save outer loop substr pointer}

        PUSH    EDI              { save outer loop s pointer    }

        MOV     ECX,EDX

        REPE    CMPSB

        POP     EDI              { restore outer loop s pointer  }

        POP     ESI           { restore outer loop substr pointer}

        JE      @@found

        MOV     ECX,EBX          { restore outer loop counter    }

        JMP     @@loop

@@fail:

        POP     EDX              { get rid of saved s pointer    }

        XOR     EAX,EAX

        JMP     @@exit

@@stringEmpty:

        XOR     EAX,EAX

        JMP     @@noWork

@@found:

        POP   EDX     { restore pointer to first char of s }

        MOV   EAX,EDI { EDI points of char after match     }

        SUB   EAX,EDX { the difference is the correct index}

@@exit:

        POP     EDI

        POP     ESI

        POP     EBX

@@noWork:

end; //SmartPosAsm

function cnsSmartPos(const substr : AnsiString;

const s : AnsiString; StartPos : Cardinal) : Integer;

begin

  dec(StartPos);

  Result := SmartPosAsm(SubStr,S,StartPos);

  if Result > 0 then Result := Result + StartPos;

end; //cnsSmartPos

function TailPos(const S, SubStr: AnsiString;

 fromPos: integer): integer;

asm

        PUSH EDI

        PUSH ESI

        PUSH EBX

        PUSH EAX

        OR EAX,EAX

        JE @@2

        OR EDX,EDX

        JE @@2

        DEC ECX

        JS @@2

        MOV EBX,[EAX-4]

        SUB EBX,ECX

        JLE @@2

        SUB EBX,[EDX-4]

        JL @@2

        INC EBX

        ADD EAX,ECX

        MOV ECX,EBX

        MOV EBX,[EDX-4]

        DEC EBX

        MOV EDI,EAX

@@1: MOV ESI,EDX

        LODSB

        REPNE SCASB

        JNE @@2

        MOV EAX,ECX

        PUSH EDI

        MOV ECX,EBX

        REPE CMPSB

        POP EDI

        MOV ECX,EAX

        JNE @@1

        LEA EAX,[EDI-1]

        POP EDX

        SUB EAX,EDX

        INC EAX

        JMP @@3

@@2: POP EAX

        XOR EAX,EAX

@@3: POP EBX

        POP ESI

        POP EDI

end;