User talk:PROXiCiDE/MathUtil

Some Small Efficiency Tweaks

This is looking good PROXiCiDE, but I've noticed there's a small efficiency tweak that can be made to the IsNumberEven and IsNumberOdd functions. At the moment, here's the assembly generated by the IsNumberEven function:

.function IsNumberEven 
  .userFlags 0
  .docString ""
  .return Bool
  .paramTable
    .param num Int
  .endParamTable
  .localTable
    .local ::temp0 int
    .local ::temp1 float
    .local ::temp2 bool
  .endLocalTable
  .code
    IMOD ::temp0 num 2 ;@line 4
    CAST ::temp1 ::temp0 ;@line 4
    CALLSTATIC math Floor ::temp0 ::temp1 ;@line 4
    COMPAREEQ ::temp2 ::temp0 0 ;@line 4
    JUMPF ::temp2 label1 ;@line 4
    RETURN True ;@line 5
    JUMP label0
    label1:
    RETURN False ;@line 7
    label0:
  .endCode
.endFunction

By changing the function to this, the generated assembly can be reduced so that it's essentially exactly the same except without the COMPAREEQ operation, and the True/False return statements are switched around:

Bool Function IsNumberEven (Int num)
	If Math.Floor(num % 2)
		Return False
	Else
		Return True
	EndIf
EndFunction

The functionality hasn't changed, and now the assembly code generated for this function looks like this:

.code
  IMOD ::temp3 num 2 ;@line 12
  CAST ::temp4 ::temp3 ;@line 12
  CALLSTATIC math Floor ::temp3 ::temp4 ;@line 12
  JUMPF ::temp3 label3 ;@line 12
  RETURN False ;@line 13
  JUMP label2
  label3:
  RETURN True ;@line 15
  label2:
.endCode

Of course, the same optimisation can also be applied to the IsNumberOdd function:

Bool Function IsNumberEven (Int num)
	If Math.Floor(num % 2)
		Return True 
	Else 
		Return False 
	EndIf
EndFunction

Another tweak can be made to make InRange significantly shorter and more efficient too:

Bool Function InRange(Float x,Float min,Float max)
	Return (min <= x && x <= max)
EndFunction

-- Cipscis (talk) 2013-02-10T15:03:06 (EST)