[llvm-branch-commits] [llvm-branch] r91831 - in /llvm/branches/Apple/Zoidberg: include/llvm/ADT/DenseMap.h lib/Transforms/Utils/SSAUpdater.cpp test/Transforms/LoopRotate/phi-duplicate.ll

[Bill Wendling]

Author: void
Date: Mon Dec 21 13:04:38 2009
New Revision: 91831

URL: http://llvm.org/viewvc/llvm-project?rev=91831&view=rev
Log:
$ svn merge -c 91819 https://llvm.org/svn/llvm-project/llvm/trunk
--- Merging r91819 into '.':
U    include/llvm/ADT/DenseMap.h
$ svn merge -c 91820 https://llvm.org/svn/llvm-project/llvm/trunk
--- Merging r91820 into '.':
A    test/Transforms/LoopRotate/phi-duplicate.ll
U    lib/Transforms/Utils/SSAUpdater.cpp


Added:
    llvm/branches/Apple/Zoidberg/test/Transforms/LoopRotate/phi-duplicate.ll
      - copied unchanged from r91820, llvm/trunk/test/Transforms/LoopRotate/phi-duplicate.ll
Modified:
    llvm/branches/Apple/Zoidberg/include/llvm/ADT/DenseMap.h
    llvm/branches/Apple/Zoidberg/lib/Transforms/Utils/SSAUpdater.cpp

Modified: llvm/branches/Apple/Zoidberg/include/llvm/ADT/DenseMap.h
URL: http://llvm.org/viewvc/llvm-project/llvm/branches/Apple/Zoidberg/include/llvm/ADT/DenseMap.h?rev=91831&r1=91830&r2=91831&view=diff

==============================================================================
--- llvm/branches/Apple/Zoidberg/include/llvm/ADT/DenseMap.h (original)
+++ llvm/branches/Apple/Zoidberg/include/llvm/ADT/DenseMap.h Mon Dec 21 13:04:38 2009
@@ -46,7 +46,7 @@
   typedef ValueT mapped_type;
   typedef BucketT value_type;
 
-  DenseMap(const DenseMap& other) {
+  DenseMap(const DenseMap &other) {
     NumBuckets = 0;
     CopyFrom(other);
   }
@@ -55,6 +55,12 @@
     init(NumInitBuckets);
   }
 
+  template<typename InputIt>
+  DenseMap(const InputIt &I, const InputIt &E) {
+    init(64);
+    insert(I, E);
+  }
+  
   ~DenseMap() {
     const KeyT EmptyKey = getEmptyKey(), TombstoneKey = getTombstoneKey();
     for (BucketT *P = Buckets, *E = Buckets+NumBuckets; P != E; ++P) {

Modified: llvm/branches/Apple/Zoidberg/lib/Transforms/Utils/SSAUpdater.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/branches/Apple/Zoidberg/lib/Transforms/Utils/SSAUpdater.cpp?rev=91831&r1=91830&r2=91831&view=diff

==============================================================================
--- llvm/branches/Apple/Zoidberg/lib/Transforms/Utils/SSAUpdater.cpp (original)
+++ llvm/branches/Apple/Zoidberg/lib/Transforms/Utils/SSAUpdater.cpp Mon Dec 21 13:04:38 2009
@@ -149,7 +149,29 @@
   if (SingularValue != 0)
     return SingularValue;
 
-  // Otherwise, we do need a PHI: insert one now.
+  // Otherwise, we do need a PHI: check to see if we already have one available
+  // in this block that produces the right value.
+  if (isa<PHINode>(BB->begin())) {
+    DenseMap<BasicBlock*, Value*> ValueMapping(PredValues.begin(),
+                                               PredValues.end());
+    PHINode *SomePHI;
+    for (BasicBlock::iterator It = BB->begin();
+         (SomePHI = dyn_cast<PHINode>(It)); ++It) {
+      // Scan this phi to see if it is what we need.
+      bool Equal = true;
+      for (unsigned i = 0, e = SomePHI->getNumIncomingValues(); i != e; ++i)
+        if (ValueMapping[SomePHI->getIncomingBlock(i)] !=
+            SomePHI->getIncomingValue(i)) {
+          Equal = false;
+          break;
+        }
+         
+      if (Equal)
+        return SomePHI;
+    }
+  }
+  
+  // Ok, we have no way out, insert a new one now.
   PHINode *InsertedPHI = PHINode::Create(PrototypeValue->getType(),
                                          PrototypeValue->getName(),
                                          &BB->front());