[llvm-commits] [llvm] r49345 - in /llvm/trunk: include/llvm/ADT/SparseBitVector.h lib/Transforms/Scalar/GVN.cpp

[Owen Anderson]

Author: resistor
Date: Mon Apr  7 12:38:23 2008
New Revision: 49345

URL: http://llvm.org/viewvc/llvm-project?rev=49345&view=rev
Log:
Add operator= implementations to SparseBitVector, allowing it to be used in GVN.  This results
in both time and memory savings for GVN.  For example, one testcase went from 10.5s to 6s with
this patch.

Modified:
    llvm/trunk/include/llvm/ADT/SparseBitVector.h
    llvm/trunk/lib/Transforms/Scalar/GVN.cpp

Modified: llvm/trunk/include/llvm/ADT/SparseBitVector.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/ADT/SparseBitVector.h?rev=49345&r1=49344&r2=49345&view=diff

==============================================================================
--- llvm/trunk/include/llvm/ADT/SparseBitVector.h (original)
+++ llvm/trunk/include/llvm/ADT/SparseBitVector.h Mon Apr  7 12:38:23 2008
@@ -89,6 +89,14 @@
     ElementIndex = RHS.ElementIndex;
     std::copy(&RHS.Bits[0], &RHS.Bits[BITWORDS_PER_ELEMENT], Bits);
   }
+  
+  // Assignment 
+  SparseBitVectorElement& operator=(const SparseBitVectorElement& RHS) {
+    ElementIndex = RHS.ElementIndex;
+    std::copy(&RHS.Bits[0], &RHS.Bits[BITWORDS_PER_ELEMENT], Bits);
+    
+    return *this;
+  }
 
   // Comparison.
   bool operator==(const SparseBitVectorElement &RHS) const {
@@ -483,6 +491,21 @@
 
     CurrElementIter = Elements.begin ();
   }
+  
+  // Assignment
+  SparseBitVector& operator=(const SparseBitVector& RHS) {
+    Elements.clear();
+    
+    ElementListConstIter ElementIter = RHS.Elements.begin();
+    while (ElementIter != RHS.Elements.end()) {
+      Elements.push_back(SparseBitVectorElement<ElementSize>(*ElementIter));
+      ++ElementIter;
+    }
+
+    CurrElementIter = Elements.begin ();
+    
+    return *this;
+  }
 
   // Test, Reset, and Set a bit in the bitmap.
   bool test(unsigned Idx) {

Modified: llvm/trunk/lib/Transforms/Scalar/GVN.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/GVN.cpp?rev=49345&r1=49344&r2=49345&view=diff

==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/GVN.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/GVN.cpp Mon Apr  7 12:38:23 2008
@@ -22,11 +22,11 @@
 #include "llvm/Instructions.h"
 #include "llvm/ParameterAttributes.h"
 #include "llvm/Value.h"
-#include "llvm/ADT/BitVector.h"
 #include "llvm/ADT/DenseMap.h"
 #include "llvm/ADT/DepthFirstIterator.h"
 #include "llvm/ADT/SmallPtrSet.h"
 #include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/SparseBitVector.h"
 #include "llvm/ADT/Statistic.h"
 #include "llvm/Analysis/Dominators.h"
 #include "llvm/Analysis/AliasAnalysis.h"
@@ -590,9 +590,9 @@
 class VISIBILITY_HIDDEN ValueNumberedSet {
   private:
     SmallPtrSet<Value*, 8> contents;
-    BitVector numbers;
+    SparseBitVector<64> numbers;
   public:
-    ValueNumberedSet() { numbers.resize(1); }
+    ValueNumberedSet() { }
     ValueNumberedSet(const ValueNumberedSet& other) {
       numbers = other.numbers;
       contents = other.contents;
@@ -610,9 +610,6 @@
     size_t size() { return contents.size(); }
     
     void set(unsigned i)  {
-      if (i >= numbers.size())
-        numbers.resize(i+1);
-      
       numbers.set(i);
     }
     
@@ -622,21 +619,12 @@
     }
     
     void reset(unsigned i)  {
-      if (i < numbers.size())
-        numbers.reset(i);
+      numbers.reset(i);
     }
     
     bool test(unsigned i)  {
-      if (i >= numbers.size())
-        return false;
-      
       return numbers.test(i);
     }
-    
-    void clear() {
-      contents.clear();
-      numbers.clear();
-    }
 };
 }
 
@@ -1598,6 +1586,10 @@
   if (isa<AllocationInst>(I))
     return false;
   
+  // Allocations are always unique, so don't bother value numbering them.
+  if (isa<AllocationInst>(I))
+    return false;
+  
   if (MemCpyInst* M = dyn_cast<MemCpyInst>(I)) {
     MemoryDependenceAnalysis& MD = getAnalysis<MemoryDependenceAnalysis>();