[SOLVED] Improved CPU cache usage at procedure TFPCustomImage.Assign
lazarus / 64-FPC development

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lagprogramming · 2023-04-23 12:25

packages/fcl-image/src/fpimage.inc has procedure
TFPCustomImage.Assign(Source: TPersistent);
Code: Pascal  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i Procedure
TFPCustomImage.Assign(Source: TPersistent); Var  Src :
TFPCustomImage;  X,Y : Integer; begin  If Source is TFPCustomImage
then    begin    Src:=TFPCustomImage(Source);    // Copy extra info  
FExtra.Assign(Src.Fextra);    // Copy palette if needed.   
SetSize(0,0); { avoid side-effects in descendant classes }   
UsePalette:=Src.UsePalette;    If UsePalette then      begin     
Palette.Count:=0;      Palette.Merge(Src.Palette);      end;    //
Copy image.    SetSize(Src.Width,Src.height);    If UsePalette then  
  For x:=0 to Src.Width-1 do        For y:=0 to src.Height-1 do      
  pixels[X,Y]:=src.pixels[X,Y]    else      For x:=0 to Src.Width-1
do        For y:=0 to src.Height-1 do          self[X,Y]:=src[X,Y];  
end  else    Inherited Assign(Source);end;
The following patch improves CPU cache usage by switching the x and y
loops. In addition, some cosmetics: two empty lines have been removed,
"Var" has been changed to "var" and "[X,Y]" has been changed to
"[x,y]".
Code: Pascal  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i diff --git
a/packages/fcl-image/src/fpimage.inc b/packages/fcl-
image/src/fpimage.incindex 3e2075900d..54be93074c 100644---
a/packages/fcl-image/src/fpimage.inc+++ b/packages/fcl-
image/src/fpimage.inc@@ -460,11 +460,9 @@ procedure
TFPCustomImage.CheckIndex (x,y:integer); end;  Procedure
TFPCustomImage.Assign(Source: TPersistent);--Var+var   Src :
TFPCustomImage;-  X,Y : Integer;-+  x,y : Integer; begin   If Source
is TFPCustomImage then     begin@@ -482,13 +480,13 @@ procedure
TFPCustomImage.CheckIndex (x,y:integer);     // Copy image.   
 SetSize(Src.Width,Src.height);     If UsePalette then-      For x:=0
to Src.Width-1 do-        For y:=0 to src.Height-1 do-        
 pixels[X,Y]:=src.pixels[X,Y]+      For y:=0 to src.Height-1 do+     
 For x:=0 to Src.Width-1 do+          pixels[x,y]:=src.pixels[x,y]   
 else-      For x:=0 to Src.Width-1 do-        For y:=0 to
src.Height-1 do-          self[X,Y]:=src[X,Y];+      For y:=0 to
src.Height-1 do+        For x:=0 to Src.Width-1 do+        
 self[x,y]:=src[x,y];     end   else     Inherited Assign(Source);

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marcov · 2023-04-23 13:55

Fixed.