unit FastcodeMinMax;

{Uncomment to Allow Conditional Moves (Pentium Pro and Above)}
//{$DEFINE AllowCMOV}

interface

//Need Functions for ShortInt, SmallInt, Word, Byte

  function Max(A, B: Integer ): Integer;  overload;
  function Max(A, B: Cardinal): Cardinal; overload;
  function Max(A, B: Int64   ): Int64;    overload;
  function Max(A, B: Single  ): Single;   overload;
  function Max(A, B: Double  ): Double;   overload;
  function Max(A, B: Extended): Extended; overload;

  function Min(A, B: Integer ): Integer;  overload;
  function Min(A, B: Cardinal): Cardinal; overload;
  function Min(A, B: Int64   ): Int64;    overload;
  function Min(A, B: Single  ): Single;   overload;
  function Min(A, B: Double  ): Double;   overload;
  function Min(A, B: Extended): Extended; overload;

implementation

function Max(A, B: Integer): Integer; overload;
asm
{$IFDEF AllowCMOV}
  cmp   edx, eax
  cmovg eax, edx
{$ELSE}
  xor   ecx, ecx
  sub   edx, eax
  setl  cl
  sub   ecx, 1
  and   edx, ecx
  add   eax, edx
{$ENDIF}
end;

function Max(A, B: Cardinal): Cardinal; overload;
asm
{$IFDEF AllowCMOV}
  cmp   edx,eax
  cmova eax,edx
{$ELSE}
  xor   ecx, ecx
  sub   eax, edx
  adc   ecx, -1
  and   eax, ecx
  add   eax, edx
{$ENDIF}
end;

function Max(A, B: Int64): Int64; overload;
asm
  xor   ecx, ecx
  mov   eax, [ebp+$08]
  mov   edx, [ebp+$0C]
  sub   eax, [ebp+$10]
  sbb   edx, [ebp+$14]
  setl  cl
  mov   eax, [ebp+8*ecx+$08]
  mov   edx, [ebp+8*ecx+$0C]
end;

function Max(A, B: Single): Single; overload;
asm
  fld   B
  fcomp A
  fstsw ax
  and   eax, $100
  shr   eax, 6 {eax = 0 or 4}
  fld   dword ptr [ebp+eax+8]
end;

function Max(A, B: Double): Double; overload;
asm
  fld   A
  fld   B
  fcomi st(0),st(1)
  jb    @@Done
  ffree st(1)
  pop   ebp
  ret   16
@@Done:
  fxch
  ffree st(1)
end;

function Max(A, B: Extended): Extended; overload;
asm
 fld    A
 fld    B
 fcomi  st(0), st(1)
 jb     @@Done
 ffree  st(1)
 pop    ebp
 ret    $18
@@Done:
 fxch
 ffree  st(1)
end;

function Min(A, B: Integer): Integer; overload;
asm
{$IFDEF AllowCMOV}
  cmp   edx, eax
  cmovl eax, edx
{$ELSE}
  xor   ecx, ecx
  sub   edx, eax
  setge cl
  sub   ecx, 1
  and   edx, ecx
  add   eax, edx
{$ENDIF}
end;

function Min(A, B: Cardinal): Cardinal; overload;
asm
{$IFDEF AllowCMOV}
  cmp   edx,eax
  cmovb eax,edx
{$ELSE}
  sub   edx, eax
  sbb   ecx, ecx
  and   edx, ecx
  add   eax, edx
{$ENDIF}
end;

function Min(A, B: Int64): Int64; overload;
asm
  mov   eax, [ebp+$08]
  xor   ecx, ecx
  mov   edx, [ebp+$0C]
  sub   eax, [ebp+$10]
  sbb   edx, [ebp+$14]
  setge cl
  mov   eax, [ebp+8*ecx+$08]
  mov   edx, [ebp+8*ecx+$0C]
end;

function Min(A, B : Single): Single; overload;
asm
  fld   A
  fcomp B
  fstsw ax
  and   eax, $100
  shr   eax, 6 {eax = 0 or 4}
  fld   dword ptr [ebp+eax+8]
end;

function Min(A, B : Double): Double; overload;
asm
  fld   A
  fld   B
  fcomi st(0),st(1)
  ja    @@Done
  ffree st(1)
  pop   ebp
  ret   16
@@Done:
  fxch
  ffree st(1)
end;

function Min(A, B : Extended): Extended; overload;
asm
 fld    A
 fld    B
 fcomi  st(0), st(1)
 ja     @@Done
 ffree  st(1)
 pop    ebp
 ret    $18
@@Done:
 fxch
 ffree  st(1)
end;

end.