Fix some null checks to actually test the part that needs checking.

[oota-llvm.git] / include / llvm / Analysis / PostDominators.h

diff --git a/include/llvm/Analysis/PostDominators.h b/include/llvm/Analysis/PostDominators.h
index 992a0cef7af684c0a14406cc45e2c07a9b02a108..359f19daf881f283397fab1e28b07d12f94bc21d 100644 (file)
--- a/include/llvm/Analysis/PostDominators.h
+++ b/include/llvm/Analysis/PostDominators.h
@@ -18,69 +18,56 @@
 
 namespace llvm {
 
-/// PostDominatorSet Class - Concrete subclass of DominatorSetBase that is used
-/// to compute the post-dominator set.  Because there can be multiple exit nodes
-/// in an LLVM function, we calculate post dominators with a special null block
-/// which is the virtual exit node that the real exit nodes all virtually branch
-/// to.  Clients should be prepared to see an entry in the dominator sets with a
-/// null BasicBlock*.
-///
-struct PostDominatorSet : public DominatorSetBase {
-  PostDominatorSet() : DominatorSetBase(true) {}
-
-  virtual bool runOnFunction(Function &F);
-
-  /// getAnalysisUsage - This pass does not modify the function at all.
-  ///
-  virtual void getAnalysisUsage(AnalysisUsage &AU) const {
-    AU.setPreservesAll();
-  }
-};
-
-
-/// ImmediatePostDominators Class - Concrete subclass of ImmediateDominatorsBase
-/// that is used to compute the immediate post-dominators.
+/// PostDominatorTree Class - Concrete subclass of DominatorTree that is used to
+/// compute the a post-dominator tree.
 ///
-struct ImmediatePostDominators : public ImmediateDominatorsBase {
-  ImmediatePostDominators() : ImmediateDominatorsBase(true) {}
+struct PostDominatorTree : public DominatorTreeBase {
+  PostDominatorTree() : DominatorTreeBase(true) {}
 
   virtual bool runOnFunction(Function &F) {
-    IDoms.clear();     // Reset from the last time we were run...
-    PostDominatorSet &DS = getAnalysis<PostDominatorSet>();
-    Roots = DS.getRoots();
-    calcIDoms(DS);
+    reset();     // Reset from the last time we were run...
+    calculate(F);
     return false;
   }
 
   virtual void getAnalysisUsage(AnalysisUsage &AU) const {
     AU.setPreservesAll();
-    AU.addRequired<PostDominatorSet>();
   }
 private:
-  void calcIDoms(const DominatorSetBase &DS);
+  void calculate(Function &F);
+  Node *getNodeForBlock(BasicBlock *BB);
+  unsigned DFSPass(BasicBlock *V, InfoRec &VInfo,unsigned N);
+  void Compress(BasicBlock *V, InfoRec &VInfo);
+  BasicBlock *Eval(BasicBlock *V);
+  void Link(BasicBlock *V, BasicBlock *W, InfoRec &WInfo);
+
+  inline BasicBlock *getIDom(BasicBlock *BB) const {
+    std::map<BasicBlock*, BasicBlock*>::const_iterator I = IDoms.find(BB);
+    return I != IDoms.end() ? I->second : 0;
+  }
 };
 
 
-/// PostDominatorTree Class - Concrete subclass of DominatorTree that is used to
-/// compute the a post-dominator tree.
-///
-struct PostDominatorTree : public DominatorTreeBase {
-  PostDominatorTree() : DominatorTreeBase(true) {}
+/// PostETForest Class - Concrete subclass of ETForestBase that is used to
+/// compute a forwards post-dominator ET-Forest.
+struct PostETForest : public ETForestBase {
+  PostETForest() : ETForestBase(true) {}
+
+  virtual void getAnalysisUsage(AnalysisUsage &AU) const {
+    AU.setPreservesAll();
+    AU.addRequired<PostDominatorTree>();
+  }
 
   virtual bool runOnFunction(Function &F) {
     reset();     // Reset from the last time we were run...
-    PostDominatorSet &DS = getAnalysis<PostDominatorSet>();
-    Roots = DS.getRoots();
-    calculate(DS);
+    PostDominatorTree &DT = getAnalysis<PostDominatorTree>();
+    Roots = DT.getRoots();
+    calculate(DT);
     return false;
   }
 
-  virtual void getAnalysisUsage(AnalysisUsage &AU) const {
-    AU.setPreservesAll();
-    AU.addRequired<PostDominatorSet>();
-  }
-private:
-  void calculate(const PostDominatorSet &DS);
+  void calculate(const PostDominatorTree &DT);
+  ETNode *getNodeForBlock(BasicBlock *BB);
 };
 
 
@@ -104,18 +91,14 @@ struct PostDominanceFrontier : public DominanceFrontierBase {
     AU.addRequired<PostDominatorTree>();
   }
 
-  // stub - dummy function, just ignore it
-  static void stub();
-
 private:
   const DomSetType &calculate(const PostDominatorTree &DT,
                               const DominatorTree::Node *Node);
 };
 
-// Make sure that any clients of this file link in PostDominators.cpp
-static IncludeFile
-POST_DOMINATOR_INCLUDE_FILE((void*)&PostDominanceFrontier::stub);
-
 } // End llvm namespace
 
+// Make sure that any clients of this file link in PostDominators.cpp
+FORCE_DEFINING_FILE_TO_BE_LINKED(PostDominanceFrontier)
+
 #endif