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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49345 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 23 insertions, 0 deletions

diff --git a/include/llvm/ADT/SparseBitVector.h b/include/llvm/ADT/SparseBitVector.h
index 1ed28607ef..4c28682d39 100644
--- a/include/llvm/ADT/SparseBitVector.h
+++ b/include/llvm/ADT/SparseBitVector.h
@@ -89,6 +89,14 @@ public:
     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 @@ public:
 
     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) {