* for all optimization levels > 1, all passes are done twice (the

    result improves the most if -Or is used as well)

compiler/aopt386.pas

@@ -40,62 +40,78 @@ Uses
 
 
 Procedure Optimize(AsmL: PAasmOutput);
-Var BlockStart, BlockEnd, HP: Pai;
+Var
+  count, max: longint;
+  BlockStart, BlockEnd, HP: Pai;
 Begin
-{setup labeltable, always necessary}
-  BlockStart := Pai(AsmL^.First);
-  BlockEnd := DFAPass1(AsmL, BlockStart);
-{Blockend now either contains an ait_marker with Kind = AsmBlockStart, or nil}
-  While Assigned(BlockStart) Do
-    Begin
-{peephole optimizations}
-      PeepHoleOptPass1(AsmL, BlockStart, BlockEnd);
-      PeepHoleOptPass1(AsmL, BlockStart, BlockEnd);
-{data flow analyzer}
-      If (cs_slowoptimize in aktglobalswitches) Then
-        Begin
-          If DFAPass2(
+  if (cs_slowoptimize in aktglobalswitches) then
+   { Optimize twice }
+    max := 2
+  else max := 1;
+  for count := 1 to max do
+    begin
+   { Setup labeltable, always necessary }
+     BlockStart := Pai(AsmL^.First);
+     BlockEnd := DFAPass1(AsmL, BlockStart);
+   { Blockend now either contains an ait_marker with Kind = AsmBlockStart, }
+   { or nil                                                                }
+     While Assigned(BlockStart) Do
+       Begin
+        { Peephole optimizations }
+         PeepHoleOptPass1(AsmL, BlockStart, BlockEnd);
+        { Only perform them twice in the first pass }
+         if count = 1 then
+           PeepHoleOptPass1(AsmL, BlockStart, BlockEnd);
+        { Data flow analyzer }
+         If (cs_slowoptimize in aktglobalswitches) Then
+           Begin
+             If DFAPass2(
 {$ifdef statedebug}
-                      AsmL,
+                         AsmL,
 {$endif statedebug}
-                            BlockStart, BlockEnd) Then
-{common subexpression elimination}
-            CSE(AsmL, BlockStart, BlockEnd);
-        End;
-{more peephole optimizations}
-      PeepHoleOptPass2(AsmL, BlockStart, BlockEnd);
-{dispose labeltabel}
-      ShutDownDFA;
-{continue where we left off, BlockEnd is either the start of an assembler
- block or nil}
-      BlockStart := BlockEnd;
-      While Assigned(BlockStart) And
-            (BlockStart^.typ = ait_Marker) And
-            (Pai_Marker(BlockStart)^.Kind = AsmBlockStart) Do
-        Begin
-         {we stopped at an assembler block, so skip it}
-         Repeat
-           BlockStart := Pai(BlockStart^.Next);
-         Until (BlockStart^.Typ = Ait_Marker) And
-               (Pai_Marker(Blockstart)^.Kind = AsmBlockEnd);
-         {blockstart now contains a pai_marker(asmblockend)}
-          If GetNextInstruction(BlockStart, HP) And
-             ((HP^.typ <> ait_Marker) Or
-              (Pai_Marker(HP)^.Kind <> AsmBlockStart)) Then
-           {there is no assembler block anymore after the current one, so
-            optimize the next block of "normal" instructions}
-            BlockEnd := DFAPass1(AsmL, BlockStart)
-           {otherwise, skip the next assembler block}
-          Else BlockStart := HP;
-        End
-   End;
+                               BlockStart, BlockEnd) Then
+              { common subexpression elimination }
+               CSE(AsmL, BlockStart, BlockEnd);
+           End;
+        { More peephole optimizations }
+         PeepHoleOptPass2(AsmL, BlockStart, BlockEnd);
+        { Dispose labeltabel }
+         ShutDownDFA;
+        { Continue where we left off, BlockEnd is either the start of an }
+        { assembler block or nil                                         }
+         BlockStart := BlockEnd;
+         While Assigned(BlockStart) And
+               (BlockStart^.typ = ait_Marker) And
+               (Pai_Marker(BlockStart)^.Kind = AsmBlockStart) Do
+           Begin
+           { We stopped at an assembler block, so skip it }
+            Repeat
+              BlockStart := Pai(BlockStart^.Next);
+            Until (BlockStart^.Typ = Ait_Marker) And
+                  (Pai_Marker(Blockstart)^.Kind = AsmBlockEnd);
+           { Blockstart now contains a pai_marker(asmblockend) }
+             If GetNextInstruction(BlockStart, HP) And
+                ((HP^.typ <> ait_Marker) Or
+                 (Pai_Marker(HP)^.Kind <> AsmBlockStart)) Then
+             { There is no assembler block anymore after the current one, so }
+             { optimize the next block of "normal" instructions              }
+               BlockEnd := DFAPass1(AsmL, BlockStart)
+             { Otherwise, skip the next assembler block }
+             Else BlockStart := HP;
+           End
+      End;
+   end;
 End;
 
 End.
 
 {
   $Log$
-  Revision 1.3  2000-07-14 05:11:48  michael
+  Revision 1.4  2000-08-19 09:10:08  jonas
+    * for all optimization levels > 1, all passes are done twice (the
+      result improves the most if -Or is used as well)
+
+  Revision 1.3  2000/07/14 05:11:48  michael
   + Patch to 1.1
 
   Revision 1.2  2000/07/13 11:32:31  michael