musicdsp.org source code archive - WSInf

END;
{$ELSE}
BEGIN
RESULT:=(Value SHR Shift) OR (($FFFFFFFF+(1-((Value AND (1 SHL 31)) SHR 31) AND ORD(Shift0))) SHL (32-Shift));
END;
{$ENDIF}
from : bero@0ok.de
comment : Ny branchless clipping functions (the first is faster than the second)
FUNCTION Clip(Value,Min,Max:SINGLE):SINGLE; ASSEMBLER; STDCALL;
CONST Constant0Dot5:SINGLE=0.5;
ASM
FLD DWORD PTR Value
FLD DWORD PTR Min
FLD DWORD PTR Max
FLD ST(2)
FSUB ST(0),ST(2)
FABS
FADD ST(0),ST(2)
FADD ST(0),ST(1)
FLD ST(3)
FSUB ST(0),ST(2)
FABS
FSUBP ST(1),ST(0)
FMUL DWORD PTR Constant0Dot5
FFREE ST(4)
FFREE ST(3)
FFREE ST(2)
FFREE ST(1)
END;
FUNCTION ClipDSP(Value:SINGLE):SINGLE; {$IFDEF CPU386} ASSEMBLER; REGISTER;
ASM
MOV EAX,DWORD PTR Value
AND EAX,$80000000
AND DWORD PTR Value,$7FFFFFFF
FLD DWORD PTR Value
FLD1
FSUBP ST(1),ST(0)
FSTP DWORD PTR Value
MOV EDX,DWORD PTR Value
AND EDX,$80000000
SHR EDX,31
NEG EDX
AND DWORD PTR Value,EDX
FLD DWORD PTR Value
FLD1
FADDP ST(1),ST(0)
FSTP DWORD PTR Value
OR DWORD PTR Value,EAX
FLD DWORD PTR Value
END;
{$ELSE}
VAR ValueCasted:LONGWORD ABSOLUTE Value;
Sign:LONGWORD;
BEGIN
Sign:=ValueCasted AND $80000000;
ValueCasted:=ValueCasted AND $7FFFFFFF;
Value:=Value-1;
ValueCasted:=ValueCasted AND (-LONGWORD((ValueCasted AND $80000000) SHR 31));
Value:=Value+1;
ValueCasted:=ValueCasted OR Sign;
RESULT:=Value;
END;
{$ENDIF}
from : stevenaajp4709@super-fast-email.com
comment : I liked your site