[llvm-commits] CVS: llvm/lib/Transforms/Scalar/LoopPreheaders.cpp

[Chris Lattner]

Changes in directory llvm/lib/Transforms/Scalar:

LoopPreheaders.cpp updated: 1.2 -> 1.3

---
Log message:

Fix major bugs in dominator set & tree information updating


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Diffs of the changes:

Index: llvm/lib/Transforms/Scalar/LoopPreheaders.cpp
diff -u llvm/lib/Transforms/Scalar/LoopPreheaders.cpp:1.2 llvm/lib/Transforms/Scalar/LoopPreheaders.cpp:1.3
--- llvm/lib/Transforms/Scalar/LoopPreheaders.cpp:1.2	Thu Sep 26 11:37:37 2002
+++ llvm/lib/Transforms/Scalar/LoopPreheaders.cpp	Sun Sep 29 16:41:38 2002
@@ -153,14 +153,18 @@
   
   // Update dominator information if it is around...
   if (DominatorSet *DS = getAnalysisToUpdate<DominatorSet>()) {
-    // We need to add information about the fact that NewBB dominates Header.
-    DS->addDominator(Header, NewBB);
-    
     // The blocks that dominate NewBB are the blocks that dominate Header,
     // minus Header, plus NewBB.
     DominatorSet::DomSetType DomSet = DS->getDominators(Header);
+    DomSet.insert(NewBB);  // We dominate ourself
     DomSet.erase(Header);  // Header does not dominate us...
     DS->addBasicBlock(NewBB, DomSet);
+
+    // The newly created basic block dominates all nodes dominated by Header.
+    for (Function::iterator I = Header->getParent()->begin(),
+           E = Header->getParent()->end(); I != E; ++I)
+      if (DS->dominates(Header, I))
+        DS->addDominator(I, NewBB);
   }
   
   // Update immediate dominator information if we have it...
@@ -178,11 +182,10 @@
     // the old header.
     //
     DominatorTree::Node *HeaderNode = DT->getNode(Header);
-    DominatorTree::Node *PHNode = DT->createNewNode(NewBB, HeaderNode);
+    DominatorTree::Node *PHNode = DT->createNewNode(NewBB,
+                                                    HeaderNode->getIDom());
     
     // Change the header node so that PNHode is the new immediate dominator
     DT->changeImmediateDominator(HeaderNode, PHNode);
   }
 }
-
-