Merge pull request #141 from georges-hatem/main

static arrays are faster? cleanup unnecessary code

Author: gcarreno

entries/ghatem-fpc/src/OneBRCproj.lpi

@@ -15,7 +15,7 @@
       <UseAppBundle Value="False"/>
       <ResourceType Value="res"/>
     </General>
-    <BuildModes Count="7">
+    <BuildModes Count="4">
       <Item1 Name="Default" Default="True"/>
       <Item2 Name="Debug">
         <CompilerOptions>
@@ -108,93 +108,6 @@
           </Other>
         </CompilerOptions>
       </Item4>
-      <Item5 Name="HashMult">
-        <CompilerOptions>
-          <Version Value="11"/>
-          <PathDelim Value="\"/>
-          <Target>
-            <Filename Value="..\..\..\bin\ghatem"/>
-          </Target>
-          <SearchPaths>
-            <IncludeFiles Value="$(ProjOutDir)"/>
-            <UnitOutputDirectory Value="..\..\..\bin\lib\$(TargetCPU)-$(TargetOS)"/>
-          </SearchPaths>
-          <CodeGeneration>
-            <SmartLinkUnit Value="True"/>
-            <Optimizations>
-              <OptimizationLevel Value="3"/>
-            </Optimizations>
-          </CodeGeneration>
-          <Linking>
-            <Debugging>
-              <GenerateDebugInfo Value="False"/>
-              <RunWithoutDebug Value="True"/>
-            </Debugging>
-            <LinkSmart Value="True"/>
-          </Linking>
-          <Other>
-            <CustomOptions Value="-dRELEASE -dHASHMULT"/>
-          </Other>
-        </CompilerOptions>
-      </Item5>
-      <Item6 Name="HashMod">
-        <CompilerOptions>
-          <Version Value="11"/>
-          <PathDelim Value="\"/>
-          <Target>
-            <Filename Value="..\..\..\bin\ghatem"/>
-          </Target>
-          <SearchPaths>
-            <IncludeFiles Value="$(ProjOutDir)"/>
-            <UnitOutputDirectory Value="..\..\..\bin\lib\$(TargetCPU)-$(TargetOS)"/>
-          </SearchPaths>
-          <CodeGeneration>
-            <SmartLinkUnit Value="True"/>
-            <Optimizations>
-              <OptimizationLevel Value="3"/>
-            </Optimizations>
-          </CodeGeneration>
-          <Linking>
-            <Debugging>
-              <GenerateDebugInfo Value="False"/>
-              <RunWithoutDebug Value="True"/>
-            </Debugging>
-            <LinkSmart Value="True"/>
-          </Linking>
-          <Other>
-            <CustomOptions Value="-dRELEASE -dHASHMOD"/>
-          </Other>
-        </CompilerOptions>
-      </Item6>
-      <Item7 Name="LEMIRE">
-        <CompilerOptions>
-          <Version Value="11"/>
-          <PathDelim Value="\"/>
-          <Target>
-            <Filename Value="..\..\..\bin\ghatem"/>
-          </Target>
-          <SearchPaths>
-            <IncludeFiles Value="$(ProjOutDir)"/>
-            <UnitOutputDirectory Value="..\..\..\bin\lib\$(TargetCPU)-$(TargetOS)"/>
-          </SearchPaths>
-          <CodeGeneration>
-            <SmartLinkUnit Value="True"/>
-            <Optimizations>
-              <OptimizationLevel Value="3"/>
-            </Optimizations>
-          </CodeGeneration>
-          <Linking>
-            <Debugging>
-              <GenerateDebugInfo Value="False"/>
-              <RunWithoutDebug Value="True"/>
-            </Debugging>
-            <LinkSmart Value="True"/>
-          </Linking>
-          <Other>
-            <CustomOptions Value="-dRELEASE -dLEMIRE"/>
-          </Other>
-        </CompilerOptions>
-      </Item7>
     </BuildModes>
     <PublishOptions>
       <Version Value="2"/>

entries/ghatem-fpc/src/onebrc.pas

@@ -5,7 +5,7 @@
 interface
 
 uses
-  Classes, SysUtils, Generics.Collections,
+  Classes, SysUtils,
   mormot.core.os, mormot.core.base;
 
 function RoundExDouble(const ATemp: Double): Double; inline;
@@ -25,18 +25,17 @@ function RoundExDouble(const ATemp: Double): Double; inline;
     Name: AnsiString;
   end;
   PStationData = ^TStationData;
-  TStationsDict = specialize TDictionary<Cardinal, PStationData>;
 
-  TKeys = array of Cardinal;
-  TValues = array of PStationData;
+  TKeys = array [0..45006] of Cardinal;
+  TValues = array [0..45006] of PStationData;
 
   { TMyDictionary }
 
   TMyDictionary = class
   private
     FHashes: TKeys;
     FValues: TValues;
-    FRecords: array of TStationData;
+    FRecords: array [0..45006] of TStationData;
     procedure InternalFind(const aKey: Cardinal; out aFound: Boolean; out aIndex: Integer);
   public
     constructor Create;
@@ -128,27 +127,11 @@ function Compare(AList: TStringList; AIndex1, AIndex2: Integer): Integer;
 
 { TMyDictionary }
 
-const
-  cHashConst: Double = (Sqrt(5) - 1) / 2;
-
 procedure TMyDictionary.InternalFind(const aKey: Cardinal; out aFound: Boolean; out aIndex: Integer);
 var vIdx: Integer;
-    vDbl: Double;
     vOffset: Integer;
 begin
-{$IFDEF HASHMULT}
-  vDbl := aKey * cHashConst;
-  vDbl := vDbl - Trunc (vDbl);
-  vIdx := Trunc (vDbl * cDictSize);
-{$ENDIF}
-{$IFDEF LEMIRE}
   vIdx := aKey * cDictSize shr 32;
-{$ENDIF}
-{$IFDEF HASHMOD}
-  vIdx := aKey mod cDictSize;
-{$ENDIF}
-
-  aFound := False;
 
   if FHashes[vIdx] = aKey then begin
     aIndex := vIdx;
@@ -170,8 +153,8 @@ procedure TMyDictionary.InternalFind(const aKey: Cardinal; out aFound: Boolean;
         aIndex := vIdx;
         aFound := True;
         break;
-      end
-      else if FHashes[vIdx] = 0 then begin
+      end;
+      if FHashes[vIdx] = 0 then begin
         // found empty bucket to use
         aIndex := vIdx;
         aFound := False;
@@ -185,10 +168,6 @@ constructor TMyDictionary.Create;
 var
   I: Integer;
 begin
-  SetLength (FHashes, cDictSize);
-  SetLength (FValues, cDictSize);
-  SetLength (FRecords, cDictSize);
-
   for I := 0 to cDictSize - 1 do begin
     FValues[I] := @FRecords[I];
   end;