[llvm-commits] CVS: llvm/lib/VMCore/AsmWriter.cpp

[Reid Spencer]

Changes in directory llvm/lib/VMCore:

AsmWriter.cpp updated: 1.153 -> 1.154
---
Log message:

Fix PR422: http://llvm.cs.uiuc.edu/PR422 .
Ouch! Changes in the lazy initialization code caused each incorporated 
function to reprocess the entire function on every lookup of a value's 
slot number. This caused a horrible slowdown in all functions. This
fix made llvm-dis go from "longer than I care to wait" (minutes) on a large 
test case to 0.53 seconds.


---
Diffs of the changes:  (+11 -2)

Index: llvm/lib/VMCore/AsmWriter.cpp
diff -u llvm/lib/VMCore/AsmWriter.cpp:1.153 llvm/lib/VMCore/AsmWriter.cpp:1.154
--- llvm/lib/VMCore/AsmWriter.cpp:1.153	Thu Jul 29 11:53:53 2004
+++ llvm/lib/VMCore/AsmWriter.cpp	Mon Aug 16 02:46:33 2004
@@ -92,7 +92,10 @@
 public:
   /// If you'd like to deal with a function instead of just a module, use 
   /// this method to get its data into the SlotMachine.
-  void incorporateFunction(const Function *F) { TheFunction = F; }
+  void incorporateFunction(const Function *F) { 
+    TheFunction = F;  
+    FunctionProcessed = false;
+  }
 
   /// After calling incorporateFunction, use this method to remove the 
   /// most recently incorporated function from the SlotMachine. This 
@@ -138,6 +141,7 @@
 
   /// @brief The function for which we are holding slot numbers
   const Function* TheFunction;
+  bool FunctionProcessed;
 
   /// @brief The TypePlanes map for the module level data
   TypedPlanes mMap;
@@ -1263,6 +1267,7 @@
 SlotMachine::SlotMachine(const Module *M) 
   : TheModule(M)    ///< Saved for lazy initialization.
   , TheFunction(0)
+  , FunctionProcessed(false)
   , mMap()
   , mTypes()
   , fMap()
@@ -1275,6 +1280,7 @@
 SlotMachine::SlotMachine(const Function *F ) 
   : TheModule( F ? F->getParent() : 0 ) ///< Saved for lazy initialization
   , TheFunction(F) ///< Saved for lazy initialization
+  , FunctionProcessed(false)
   , mMap()
   , mTypes()
   , fMap()
@@ -1287,7 +1293,7 @@
     processModule(); 
     TheModule = 0; ///< Prevent re-processing next time we're called.
   }
-  if ( TheFunction ) { 
+  if ( TheFunction && ! FunctionProcessed) { 
     processFunction(); 
   }
 }
@@ -1331,6 +1337,8 @@
     }
   }
 
+  FunctionProcessed = true;
+
   SC_DEBUG("end processFunction!\n");
 }
 
@@ -1343,6 +1351,7 @@
   fMap.clear(); // Simply discard the function level map
   fTypes.clear();
   TheFunction = 0;
+  FunctionProcessed = false;
   SC_DEBUG("end purgeFunction!\n");
 }