Completely merge the implementation details of DomTree and PostDomTree.

[oota-llvm.git] / lib / VMCore / DominatorCalculation.h

diff --git a/lib/VMCore/DominatorCalculation.h b/lib/VMCore/DominatorCalculation.h
deleted file mode 100644 (file)
index 1d245d4..0000000
--- a/lib/VMCore/DominatorCalculation.h
+++ /dev/null
@@ -1,106 +0,0 @@
-//==- DominatorCalculation.h - Dominator Calculation -------------*- C++ -*-==//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file was developed by Owen Anderson and is distributed under
-// the University of Illinois Open Source License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-
-#ifndef LLVM_VMCORE_DOMINATOR_CALCULATION_H
-#define LLVM_VMCORE_DOMINATOR_CALCULATION_H
-
-#include "llvm/Analysis/Dominators.h"
-#include "llvm/Analysis/DominatorInternals.h"
-
-//===----------------------------------------------------------------------===//
-//
-// DominatorTree construction - This pass constructs immediate dominator
-// information for a flow-graph based on the algorithm described in this
-// document:
-//
-//   A Fast Algorithm for Finding Dominators in a Flowgraph
-//   T. Lengauer & R. Tarjan, ACM TOPLAS July 1979, pgs 121-141.
-//
-// This implements both the O(n*ack(n)) and the O(n*log(n)) versions of EVAL and
-// LINK, but it turns out that the theoretically slower O(n*log(n))
-// implementation is actually faster than the "efficient" algorithm (even for
-// large CFGs) because the constant overheads are substantially smaller.  The
-// lower-complexity version can be enabled with the following #define:
-//
-#define BALANCE_IDOM_TREE 0
-//
-//===----------------------------------------------------------------------===//
-
-namespace llvm {
-  
-void DTcalculate(DominatorTree& DT, Function &F) {
-  BasicBlock* Root = DT.Roots[0];
-
-  // Add a node for the root...
-  DT.DomTreeNodes[Root] = DT.RootNode = new DomTreeNode(Root, 0);
-
-  // Step #1: Number blocks in depth-first order and initialize variables used
-  // in later stages of the algorithm.
-  unsigned N = DFSPass<GraphTraits<BasicBlock*> >(DT, Root, 0);
-
-  for (unsigned i = N; i >= 2; --i) {
-    BasicBlock *W = DT.Vertex[i];
-    DominatorTree::InfoRec &WInfo = DT.Info[W];
-
-    // Step #2: Calculate the semidominators of all vertices
-    for (pred_iterator PI = pred_begin(W), E = pred_end(W); PI != E; ++PI)
-      if (DT.Info.count(*PI)) {  // Only if this predecessor is reachable!
-        unsigned SemiU = DT.Info[Eval<GraphTraits<BasicBlock*> >(DT, *PI)].Semi;
-        if (SemiU < WInfo.Semi)
-          WInfo.Semi = SemiU;
-      }
-
-    DT.Info[DT.Vertex[WInfo.Semi]].Bucket.push_back(W);
-
-    BasicBlock *WParent = WInfo.Parent;
-    Link<GraphTraits<BasicBlock*> >(DT, WParent, W, WInfo);
-
-    // Step #3: Implicitly define the immediate dominator of vertices
-    std::vector<BasicBlock*> &WParentBucket = DT.Info[WParent].Bucket;
-    while (!WParentBucket.empty()) {
-      BasicBlock *V = WParentBucket.back();
-      WParentBucket.pop_back();
-      BasicBlock *U = Eval<GraphTraits<BasicBlock*> >(DT, V);
-      DT.IDoms[V] = DT.Info[U].Semi < DT.Info[V].Semi ? U : WParent;
-    }
-  }
-
-  // Step #4: Explicitly define the immediate dominator of each vertex
-  for (unsigned i = 2; i <= N; ++i) {
-    BasicBlock *W = DT.Vertex[i];
-    BasicBlock *&WIDom = DT.IDoms[W];
-    if (WIDom != DT.Vertex[DT.Info[W].Semi])
-      WIDom = DT.IDoms[WIDom];
-  }
-
-  // Loop over all of the reachable blocks in the function...
-  for (Function::iterator I = F.begin(), E = F.end(); I != E; ++I)
-    if (BasicBlock *ImmDom = DT.getIDom(I)) {  // Reachable block.
-      DomTreeNode *BBNode = DT.DomTreeNodes[I];
-      if (BBNode) continue;  // Haven't calculated this node yet?
-
-      // Get or calculate the node for the immediate dominator
-      DomTreeNode *IDomNode = DT.getNodeForBlock(ImmDom);
-
-      // Add a new tree node for this BasicBlock, and link it as a child of
-      // IDomNode
-      DomTreeNode *C = new DomTreeNode(I, IDomNode);
-      DT.DomTreeNodes[I] = IDomNode->addChild(C);
-    }
-
-  // Free temporary memory used to construct idom's
-  DT.Info.clear();
-  DT.IDoms.clear();
-  std::vector<BasicBlock*>().swap(DT.Vertex);
-
-  DT.updateDFSNumbers();
-}
-
-}
-#endif