2002-08-02 16:43:03 +00:00
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//===- Dominators.cpp - Dominator Calculation -----------------------------===//
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2005-04-21 23:48:37 +00:00
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//
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2003-10-20 19:43:21 +00:00
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// The LLVM Compiler Infrastructure
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//
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// This file was developed by the LLVM research group and is distributed under
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// the University of Illinois Open Source License. See LICENSE.TXT for details.
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2005-04-21 23:48:37 +00:00
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//
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2003-10-20 19:43:21 +00:00
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//===----------------------------------------------------------------------===//
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2001-07-02 05:46:38 +00:00
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//
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2002-08-02 16:43:03 +00:00
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// This file implements simple dominator construction algorithms for finding
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// forward dominators. Postdominators are available in libanalysis, but are not
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// included in libvmcore, because it's not needed. Forward dominators are
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// needed to support the Verifier pass.
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2001-07-02 05:46:38 +00:00
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//
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//===----------------------------------------------------------------------===//
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#include "llvm/Analysis/Dominators.h"
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2002-02-12 21:07:25 +00:00
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#include "llvm/Support/CFG.h"
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2002-07-27 01:12:17 +00:00
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#include "llvm/Assembly/Writer.h"
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2004-09-01 22:55:40 +00:00
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#include "llvm/ADT/DepthFirstIterator.h"
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#include "llvm/ADT/SetOperations.h"
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2007-03-27 20:50:46 +00:00
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#include "llvm/ADT/SmallPtrSet.h"
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2007-03-26 23:18:28 +00:00
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#include "llvm/Instructions.h"
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2004-06-05 00:24:59 +00:00
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#include <algorithm>
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2003-11-21 20:23:48 +00:00
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using namespace llvm;
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2003-11-11 22:41:34 +00:00
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2003-12-07 00:38:08 +00:00
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//===----------------------------------------------------------------------===//
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// ImmediateDominators Implementation
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//===----------------------------------------------------------------------===//
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//
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// Immediate Dominators construction - This pass constructs immediate dominator
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// information for a flow-graph based on the algorithm described in this
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// document:
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//
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// A Fast Algorithm for Finding Dominators in a Flowgraph
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// T. Lengauer & R. Tarjan, ACM TOPLAS July 1979, pgs 121-141.
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//
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// This implements both the O(n*ack(n)) and the O(n*log(n)) versions of EVAL and
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// LINK, but it turns out that the theoretically slower O(n*log(n))
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// implementation is actually faster than the "efficient" algorithm (even for
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// large CFGs) because the constant overheads are substantially smaller. The
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// lower-complexity version can be enabled with the following #define:
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//
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#define BALANCE_IDOM_TREE 0
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//
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//===----------------------------------------------------------------------===//
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2006-08-27 22:30:17 +00:00
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static RegisterPass<ImmediateDominators>
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2003-12-07 00:38:08 +00:00
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C("idom", "Immediate Dominators Construction", true);
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unsigned ImmediateDominators::DFSPass(BasicBlock *V, InfoRec &VInfo,
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unsigned N) {
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2007-04-09 06:44:42 +00:00
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// This is more understandable as a recursive algorithm, but we can't use the
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// recursive algorithm due to stack depth issues. Keep it here for
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// documentation purposes.
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#if 0
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2003-12-07 00:38:08 +00:00
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VInfo.Semi = ++N;
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VInfo.Label = V;
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Vertex.push_back(V); // Vertex[n] = V;
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//Info[V].Ancestor = 0; // Ancestor[n] = 0
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2007-04-09 06:44:42 +00:00
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//Info[V].Child = 0; // Child[v] = 0
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2003-12-07 00:38:08 +00:00
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VInfo.Size = 1; // Size[v] = 1
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for (succ_iterator SI = succ_begin(V), E = succ_end(V); SI != E; ++SI) {
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InfoRec &SuccVInfo = Info[*SI];
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if (SuccVInfo.Semi == 0) {
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SuccVInfo.Parent = V;
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N = DFSPass(*SI, SuccVInfo, N);
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}
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}
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2007-04-09 06:44:42 +00:00
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#else
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std::vector<std::pair<BasicBlock*, unsigned> > Worklist;
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Worklist.push_back(std::make_pair(V, 0U));
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while (!Worklist.empty()) {
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BasicBlock *BB = Worklist.back().first;
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unsigned NextSucc = Worklist.back().second;
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// First time we visited this BB?
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if (NextSucc == 0) {
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InfoRec &BBInfo = Info[BB];
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BBInfo.Semi = ++N;
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BBInfo.Label = BB;
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Vertex.push_back(BB); // Vertex[n] = V;
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//BBInfo[V].Ancestor = 0; // Ancestor[n] = 0
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//BBInfo[V].Child = 0; // Child[v] = 0
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BBInfo.Size = 1; // Size[v] = 1
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}
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// If we are done with this block, remove it from the worklist.
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if (NextSucc == BB->getTerminator()->getNumSuccessors()) {
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Worklist.pop_back();
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continue;
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}
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// Otherwise, increment the successor number for the next time we get to it.
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++Worklist.back().second;
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// Visit the successor next, if it isn't already visited.
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BasicBlock *Succ = BB->getTerminator()->getSuccessor(NextSucc);
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InfoRec &SuccVInfo = Info[Succ];
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if (SuccVInfo.Semi == 0) {
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SuccVInfo.Parent = BB;
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Worklist.push_back(std::make_pair(Succ, 0U));
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}
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}
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#endif
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2003-12-07 00:38:08 +00:00
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return N;
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}
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void ImmediateDominators::Compress(BasicBlock *V, InfoRec &VInfo) {
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BasicBlock *VAncestor = VInfo.Ancestor;
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InfoRec &VAInfo = Info[VAncestor];
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if (VAInfo.Ancestor == 0)
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return;
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Compress(VAncestor, VAInfo);
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2005-04-21 23:48:37 +00:00
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BasicBlock *VAncestorLabel = VAInfo.Label;
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2003-12-07 00:38:08 +00:00
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BasicBlock *VLabel = VInfo.Label;
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if (Info[VAncestorLabel].Semi < Info[VLabel].Semi)
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VInfo.Label = VAncestorLabel;
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VInfo.Ancestor = VAInfo.Ancestor;
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}
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BasicBlock *ImmediateDominators::Eval(BasicBlock *V) {
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InfoRec &VInfo = Info[V];
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#if !BALANCE_IDOM_TREE
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// Higher-complexity but faster implementation
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if (VInfo.Ancestor == 0)
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return V;
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Compress(V, VInfo);
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return VInfo.Label;
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#else
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// Lower-complexity but slower implementation
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if (VInfo.Ancestor == 0)
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return VInfo.Label;
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Compress(V, VInfo);
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BasicBlock *VLabel = VInfo.Label;
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BasicBlock *VAncestorLabel = Info[VInfo.Ancestor].Label;
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if (Info[VAncestorLabel].Semi >= Info[VLabel].Semi)
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return VLabel;
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else
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return VAncestorLabel;
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#endif
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}
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void ImmediateDominators::Link(BasicBlock *V, BasicBlock *W, InfoRec &WInfo){
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#if !BALANCE_IDOM_TREE
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// Higher-complexity but faster implementation
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WInfo.Ancestor = V;
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#else
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// Lower-complexity but slower implementation
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BasicBlock *WLabel = WInfo.Label;
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unsigned WLabelSemi = Info[WLabel].Semi;
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BasicBlock *S = W;
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InfoRec *SInfo = &Info[S];
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2005-04-21 23:48:37 +00:00
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2003-12-07 00:38:08 +00:00
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BasicBlock *SChild = SInfo->Child;
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InfoRec *SChildInfo = &Info[SChild];
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2005-04-21 23:48:37 +00:00
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2003-12-07 00:38:08 +00:00
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while (WLabelSemi < Info[SChildInfo->Label].Semi) {
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BasicBlock *SChildChild = SChildInfo->Child;
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if (SInfo->Size+Info[SChildChild].Size >= 2*SChildInfo->Size) {
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SChildInfo->Ancestor = S;
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SInfo->Child = SChild = SChildChild;
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SChildInfo = &Info[SChild];
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} else {
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SChildInfo->Size = SInfo->Size;
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S = SInfo->Ancestor = SChild;
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SInfo = SChildInfo;
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SChild = SChildChild;
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SChildInfo = &Info[SChild];
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}
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}
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2005-04-21 23:48:37 +00:00
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2003-12-07 00:38:08 +00:00
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InfoRec &VInfo = Info[V];
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SInfo->Label = WLabel;
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2005-04-21 23:48:37 +00:00
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2003-12-07 00:38:08 +00:00
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assert(V != W && "The optimization here will not work in this case!");
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unsigned WSize = WInfo.Size;
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unsigned VSize = (VInfo.Size += WSize);
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2005-04-21 23:48:37 +00:00
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2003-12-07 00:38:08 +00:00
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if (VSize < 2*WSize)
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std::swap(S, VInfo.Child);
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2005-04-21 23:48:37 +00:00
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2003-12-07 00:38:08 +00:00
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while (S) {
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SInfo = &Info[S];
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SInfo->Ancestor = V;
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S = SInfo->Child;
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}
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#endif
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}
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bool ImmediateDominators::runOnFunction(Function &F) {
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IDoms.clear(); // Reset from the last time we were run...
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BasicBlock *Root = &F.getEntryBlock();
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Roots.clear();
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Roots.push_back(Root);
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Vertex.push_back(0);
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2005-04-21 23:48:37 +00:00
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2003-12-07 00:38:08 +00:00
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// Step #1: Number blocks in depth-first order and initialize variables used
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// in later stages of the algorithm.
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unsigned N = 0;
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for (unsigned i = 0, e = Roots.size(); i != e; ++i)
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N = DFSPass(Roots[i], Info[Roots[i]], 0);
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for (unsigned i = N; i >= 2; --i) {
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BasicBlock *W = Vertex[i];
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InfoRec &WInfo = Info[W];
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// Step #2: Calculate the semidominators of all vertices
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for (pred_iterator PI = pred_begin(W), E = pred_end(W); PI != E; ++PI)
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if (Info.count(*PI)) { // Only if this predecessor is reachable!
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unsigned SemiU = Info[Eval(*PI)].Semi;
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if (SemiU < WInfo.Semi)
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WInfo.Semi = SemiU;
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}
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2005-04-21 23:48:37 +00:00
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2003-12-07 00:38:08 +00:00
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Info[Vertex[WInfo.Semi]].Bucket.push_back(W);
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BasicBlock *WParent = WInfo.Parent;
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Link(WParent, W, WInfo);
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// Step #3: Implicitly define the immediate dominator of vertices
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std::vector<BasicBlock*> &WParentBucket = Info[WParent].Bucket;
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while (!WParentBucket.empty()) {
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BasicBlock *V = WParentBucket.back();
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WParentBucket.pop_back();
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BasicBlock *U = Eval(V);
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IDoms[V] = Info[U].Semi < Info[V].Semi ? U : WParent;
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}
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}
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// Step #4: Explicitly define the immediate dominator of each vertex
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for (unsigned i = 2; i <= N; ++i) {
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BasicBlock *W = Vertex[i];
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BasicBlock *&WIDom = IDoms[W];
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if (WIDom != Vertex[Info[W].Semi])
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WIDom = IDoms[WIDom];
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}
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// Free temporary memory used to construct idom's
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Info.clear();
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std::vector<BasicBlock*>().swap(Vertex);
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return false;
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}
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2006-08-01 22:24:47 +00:00
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/// dominates - Return true if A dominates B.
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///
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bool ImmediateDominatorsBase::dominates(BasicBlock *A, BasicBlock *B) const {
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assert(A && B && "Null pointers?");
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// Walk up the dominator tree from B to determine if A dom B.
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while (A != B && B)
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B = get(B);
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return A == B;
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}
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2004-12-07 04:03:45 +00:00
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void ImmediateDominatorsBase::print(std::ostream &o, const Module* ) const {
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2004-06-19 20:04:47 +00:00
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Function *F = getRoots()[0]->getParent();
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for (Function::iterator I = F->begin(), E = F->end(); I != E; ++I) {
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2003-12-07 00:38:08 +00:00
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o << " Immediate Dominator For Basic Block:";
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2004-06-19 20:04:47 +00:00
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WriteAsOperand(o, I, false);
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2003-12-07 00:38:08 +00:00
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o << " is:";
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2004-06-19 20:04:47 +00:00
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if (BasicBlock *ID = get(I))
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WriteAsOperand(o, ID, false);
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2003-12-07 00:38:08 +00:00
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else
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o << " <<exit node>>";
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o << "\n";
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}
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o << "\n";
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}
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2007-04-07 18:23:27 +00:00
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namespace llvm {
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static std::ostream &operator<<(std::ostream &o,
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const std::set<BasicBlock*> &BBs) {
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for (std::set<BasicBlock*>::const_iterator I = BBs.begin(), E = BBs.end();
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I != E; ++I)
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if (*I)
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WriteAsOperand(o, *I, false);
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else
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o << " <<exit node>>";
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return o;
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}
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}
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2001-07-02 05:46:38 +00:00
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//===----------------------------------------------------------------------===//
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// DominatorTree Implementation
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//===----------------------------------------------------------------------===//
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2006-08-27 22:30:17 +00:00
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static RegisterPass<DominatorTree>
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2002-07-30 16:27:52 +00:00
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E("domtree", "Dominator Tree Construction", true);
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2002-01-31 00:42:27 +00:00
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2002-07-26 18:40:14 +00:00
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// DominatorTreeBase::reset - Free all of the tree node memory.
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2001-07-02 05:46:38 +00:00
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//
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2005-04-21 23:48:37 +00:00
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void DominatorTreeBase::reset() {
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2001-07-02 05:46:38 +00:00
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for (NodeMapType::iterator I = Nodes.begin(), E = Nodes.end(); I != E; ++I)
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delete I->second;
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2002-01-31 00:42:27 +00:00
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Nodes.clear();
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2003-09-10 20:37:51 +00:00
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RootNode = 0;
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2001-07-02 05:46:38 +00:00
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}
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2003-09-11 16:26:13 +00:00
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void DominatorTreeBase::Node::setIDom(Node *NewIDom) {
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2002-09-26 16:14:41 +00:00
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assert(IDom && "No immediate dominator?");
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if (IDom != NewIDom) {
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std::vector<Node*>::iterator I =
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std::find(IDom->Children.begin(), IDom->Children.end(), this);
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assert(I != IDom->Children.end() &&
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"Not in immediate dominator children set!");
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// I am no longer your child...
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|
|
IDom->Children.erase(I);
|
|
|
|
|
|
|
|
// Switch to new dominator
|
|
|
|
IDom = NewIDom;
|
|
|
|
IDom->Children.push_back(this);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2003-12-07 00:38:08 +00:00
|
|
|
DominatorTreeBase::Node *DominatorTree::getNodeForBlock(BasicBlock *BB) {
|
|
|
|
Node *&BBNode = Nodes[BB];
|
|
|
|
if (BBNode) return BBNode;
|
|
|
|
|
|
|
|
// Haven't calculated this node yet? Get or calculate the node for the
|
|
|
|
// immediate dominator.
|
|
|
|
BasicBlock *IDom = getAnalysis<ImmediateDominators>()[BB];
|
|
|
|
Node *IDomNode = getNodeForBlock(IDom);
|
2005-04-21 23:48:37 +00:00
|
|
|
|
2003-12-07 00:38:08 +00:00
|
|
|
// Add a new tree node for this BasicBlock, and link it as a child of
|
|
|
|
// IDomNode
|
|
|
|
return BBNode = IDomNode->addChild(new Node(BB, IDomNode));
|
|
|
|
}
|
2002-09-26 16:14:41 +00:00
|
|
|
|
2003-12-07 00:38:08 +00:00
|
|
|
void DominatorTree::calculate(const ImmediateDominators &ID) {
|
2003-09-10 20:37:51 +00:00
|
|
|
assert(Roots.size() == 1 && "DominatorTree should have 1 root block!");
|
|
|
|
BasicBlock *Root = Roots[0];
|
|
|
|
Nodes[Root] = RootNode = new Node(Root, 0); // Add a node for the root...
|
2001-07-02 05:46:38 +00:00
|
|
|
|
2004-06-19 20:13:48 +00:00
|
|
|
Function *F = Root->getParent();
|
2003-12-07 00:38:08 +00:00
|
|
|
// Loop over all of the reachable blocks in the function...
|
2004-06-19 20:13:48 +00:00
|
|
|
for (Function::iterator I = F->begin(), E = F->end(); I != E; ++I)
|
|
|
|
if (BasicBlock *ImmDom = ID.get(I)) { // Reachable block.
|
|
|
|
Node *&BBNode = Nodes[I];
|
|
|
|
if (!BBNode) { // Haven't calculated this node yet?
|
|
|
|
// Get or calculate the node for the immediate dominator
|
|
|
|
Node *IDomNode = getNodeForBlock(ImmDom);
|
|
|
|
|
|
|
|
// Add a new tree node for this BasicBlock, and link it as a child of
|
|
|
|
// IDomNode
|
|
|
|
BBNode = IDomNode->addChild(new Node(I, IDomNode));
|
|
|
|
}
|
2001-07-02 05:46:38 +00:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2002-07-31 19:32:01 +00:00
|
|
|
static std::ostream &operator<<(std::ostream &o,
|
|
|
|
const DominatorTreeBase::Node *Node) {
|
2003-09-11 16:26:13 +00:00
|
|
|
if (Node->getBlock())
|
|
|
|
WriteAsOperand(o, Node->getBlock(), false);
|
2003-09-10 20:37:51 +00:00
|
|
|
else
|
|
|
|
o << " <<exit node>>";
|
|
|
|
return o << "\n";
|
2002-07-27 01:12:17 +00:00
|
|
|
}
|
|
|
|
|
2002-07-31 19:32:01 +00:00
|
|
|
static void PrintDomTree(const DominatorTreeBase::Node *N, std::ostream &o,
|
2002-07-27 01:12:17 +00:00
|
|
|
unsigned Lev) {
|
2003-09-10 20:37:51 +00:00
|
|
|
o << std::string(2*Lev, ' ') << "[" << Lev << "] " << N;
|
2005-04-21 23:48:37 +00:00
|
|
|
for (DominatorTreeBase::Node::const_iterator I = N->begin(), E = N->end();
|
2003-09-10 20:37:51 +00:00
|
|
|
I != E; ++I)
|
2002-07-27 01:12:17 +00:00
|
|
|
PrintDomTree(*I, o, Lev+1);
|
|
|
|
}
|
|
|
|
|
2004-12-07 04:03:45 +00:00
|
|
|
void DominatorTreeBase::print(std::ostream &o, const Module* ) const {
|
2002-07-27 01:12:17 +00:00
|
|
|
o << "=============================--------------------------------\n"
|
|
|
|
<< "Inorder Dominator Tree:\n";
|
2003-09-10 20:37:51 +00:00
|
|
|
PrintDomTree(getRootNode(), o, 1);
|
2002-07-27 01:12:17 +00:00
|
|
|
}
|
2001-07-02 05:46:38 +00:00
|
|
|
|
|
|
|
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
// DominanceFrontier Implementation
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
|
2006-08-27 22:30:17 +00:00
|
|
|
static RegisterPass<DominanceFrontier>
|
2002-07-30 16:27:52 +00:00
|
|
|
G("domfrontier", "Dominance Frontier Construction", true);
|
2002-01-31 00:42:27 +00:00
|
|
|
|
2007-04-09 06:10:06 +00:00
|
|
|
namespace {
|
|
|
|
class DFCalculateWorkObject {
|
|
|
|
public:
|
|
|
|
DFCalculateWorkObject(BasicBlock *B, BasicBlock *P,
|
|
|
|
const DominatorTree::Node *N,
|
|
|
|
const DominatorTree::Node *PN)
|
|
|
|
: currentBB(B), parentBB(P), Node(N), parentNode(PN) {}
|
|
|
|
BasicBlock *currentBB;
|
|
|
|
BasicBlock *parentBB;
|
|
|
|
const DominatorTree::Node *Node;
|
|
|
|
const DominatorTree::Node *parentNode;
|
|
|
|
};
|
|
|
|
}
|
|
|
|
|
2002-04-28 16:21:30 +00:00
|
|
|
const DominanceFrontier::DomSetType &
|
2005-04-21 23:48:37 +00:00
|
|
|
DominanceFrontier::calculate(const DominatorTree &DT,
|
2002-07-26 18:40:14 +00:00
|
|
|
const DominatorTree::Node *Node) {
|
2003-09-11 16:26:13 +00:00
|
|
|
BasicBlock *BB = Node->getBlock();
|
2007-03-20 21:25:31 +00:00
|
|
|
DomSetType *Result = NULL;
|
|
|
|
|
2007-03-26 23:17:19 +00:00
|
|
|
std::vector<DFCalculateWorkObject> workList;
|
2007-03-27 20:50:46 +00:00
|
|
|
SmallPtrSet<BasicBlock *, 32> visited;
|
2007-03-20 21:25:31 +00:00
|
|
|
|
2007-03-26 23:17:19 +00:00
|
|
|
workList.push_back(DFCalculateWorkObject(BB, NULL, Node, NULL));
|
2007-03-20 21:25:31 +00:00
|
|
|
do {
|
2007-03-26 23:17:19 +00:00
|
|
|
DFCalculateWorkObject *currentW = &workList.back();
|
2007-03-20 21:25:31 +00:00
|
|
|
assert (currentW && "Missing work object.");
|
|
|
|
|
|
|
|
BasicBlock *currentBB = currentW->currentBB;
|
|
|
|
BasicBlock *parentBB = currentW->parentBB;
|
|
|
|
const DominatorTree::Node *currentNode = currentW->Node;
|
|
|
|
const DominatorTree::Node *parentNode = currentW->parentNode;
|
|
|
|
assert (currentBB && "Invalid work object. Missing current Basic Block");
|
|
|
|
assert (currentNode && "Invalid work object. Missing current Node");
|
|
|
|
DomSetType &S = Frontiers[currentBB];
|
|
|
|
|
|
|
|
// Visit each block only once.
|
|
|
|
if (visited.count(currentBB) == 0) {
|
|
|
|
visited.insert(currentBB);
|
|
|
|
|
|
|
|
// Loop over CFG successors to calculate DFlocal[currentNode]
|
|
|
|
for (succ_iterator SI = succ_begin(currentBB), SE = succ_end(currentBB);
|
|
|
|
SI != SE; ++SI) {
|
|
|
|
// Does Node immediately dominate this successor?
|
|
|
|
if (DT[*SI]->getIDom() != currentNode)
|
|
|
|
S.insert(*SI);
|
|
|
|
}
|
|
|
|
}
|
2001-07-02 05:46:38 +00:00
|
|
|
|
2007-03-20 21:25:31 +00:00
|
|
|
// At this point, S is DFlocal. Now we union in DFup's of our children...
|
|
|
|
// Loop through and visit the nodes that Node immediately dominates (Node's
|
|
|
|
// children in the IDomTree)
|
|
|
|
bool visitChild = false;
|
|
|
|
for (DominatorTree::Node::const_iterator NI = currentNode->begin(),
|
|
|
|
NE = currentNode->end(); NI != NE; ++NI) {
|
|
|
|
DominatorTree::Node *IDominee = *NI;
|
|
|
|
BasicBlock *childBB = IDominee->getBlock();
|
|
|
|
if (visited.count(childBB) == 0) {
|
2007-04-09 06:10:06 +00:00
|
|
|
workList.push_back(DFCalculateWorkObject(childBB, currentBB,
|
|
|
|
IDominee, currentNode));
|
2007-03-20 21:25:31 +00:00
|
|
|
visitChild = true;
|
|
|
|
}
|
|
|
|
}
|
2001-07-02 05:46:38 +00:00
|
|
|
|
2007-03-20 21:25:31 +00:00
|
|
|
// If all children are visited or there is any child then pop this block
|
|
|
|
// from the workList.
|
|
|
|
if (!visitChild) {
|
|
|
|
|
|
|
|
if (!parentBB) {
|
|
|
|
Result = &S;
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
|
|
|
|
DomSetType::const_iterator CDFI = S.begin(), CDFE = S.end();
|
|
|
|
DomSetType &parentSet = Frontiers[parentBB];
|
|
|
|
for (; CDFI != CDFE; ++CDFI) {
|
|
|
|
if (!parentNode->properlyDominates(DT[*CDFI]))
|
|
|
|
parentSet.insert(*CDFI);
|
|
|
|
}
|
|
|
|
workList.pop_back();
|
2001-07-02 05:46:38 +00:00
|
|
|
}
|
|
|
|
|
2007-03-20 21:25:31 +00:00
|
|
|
} while (!workList.empty());
|
|
|
|
|
|
|
|
return *Result;
|
2001-07-02 05:46:38 +00:00
|
|
|
}
|
2001-07-06 16:58:22 +00:00
|
|
|
|
2004-12-07 04:03:45 +00:00
|
|
|
void DominanceFrontierBase::print(std::ostream &o, const Module* ) const {
|
2002-07-27 01:12:17 +00:00
|
|
|
for (const_iterator I = begin(), E = end(); I != E; ++I) {
|
2003-09-10 20:37:51 +00:00
|
|
|
o << " DomFrontier for BB";
|
|
|
|
if (I->first)
|
|
|
|
WriteAsOperand(o, I->first, false);
|
|
|
|
else
|
|
|
|
o << " <<exit node>>";
|
|
|
|
o << " is:\t" << I->second << "\n";
|
2002-07-27 01:12:17 +00:00
|
|
|
}
|
|
|
|
}
|
2003-11-11 22:41:34 +00:00
|
|
|
|
2006-01-08 08:22:18 +00:00
|
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
// ETOccurrence Implementation
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
|
|
|
|
void ETOccurrence::Splay() {
|
|
|
|
ETOccurrence *father;
|
|
|
|
ETOccurrence *grandfather;
|
|
|
|
int occdepth;
|
|
|
|
int fatherdepth;
|
|
|
|
|
|
|
|
while (Parent) {
|
|
|
|
occdepth = Depth;
|
|
|
|
|
|
|
|
father = Parent;
|
|
|
|
fatherdepth = Parent->Depth;
|
|
|
|
grandfather = father->Parent;
|
|
|
|
|
|
|
|
// If we have no grandparent, a single zig or zag will do.
|
|
|
|
if (!grandfather) {
|
|
|
|
setDepthAdd(fatherdepth);
|
|
|
|
MinOccurrence = father->MinOccurrence;
|
|
|
|
Min = father->Min;
|
|
|
|
|
|
|
|
// See what we have to rotate
|
|
|
|
if (father->Left == this) {
|
|
|
|
// Zig
|
|
|
|
father->setLeft(Right);
|
|
|
|
setRight(father);
|
|
|
|
if (father->Left)
|
|
|
|
father->Left->setDepthAdd(occdepth);
|
|
|
|
} else {
|
|
|
|
// Zag
|
|
|
|
father->setRight(Left);
|
|
|
|
setLeft(father);
|
|
|
|
if (father->Right)
|
|
|
|
father->Right->setDepthAdd(occdepth);
|
|
|
|
}
|
|
|
|
father->setDepth(-occdepth);
|
|
|
|
Parent = NULL;
|
|
|
|
|
|
|
|
father->recomputeMin();
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
|
|
|
// If we have a grandfather, we need to do some
|
|
|
|
// combination of zig and zag.
|
|
|
|
int grandfatherdepth = grandfather->Depth;
|
|
|
|
|
|
|
|
setDepthAdd(fatherdepth + grandfatherdepth);
|
|
|
|
MinOccurrence = grandfather->MinOccurrence;
|
|
|
|
Min = grandfather->Min;
|
|
|
|
|
|
|
|
ETOccurrence *greatgrandfather = grandfather->Parent;
|
|
|
|
|
|
|
|
if (grandfather->Left == father) {
|
|
|
|
if (father->Left == this) {
|
|
|
|
// Zig zig
|
|
|
|
grandfather->setLeft(father->Right);
|
|
|
|
father->setLeft(Right);
|
|
|
|
setRight(father);
|
|
|
|
father->setRight(grandfather);
|
|
|
|
|
|
|
|
father->setDepth(-occdepth);
|
|
|
|
|
|
|
|
if (father->Left)
|
|
|
|
father->Left->setDepthAdd(occdepth);
|
|
|
|
|
|
|
|
grandfather->setDepth(-fatherdepth);
|
|
|
|
if (grandfather->Left)
|
|
|
|
grandfather->Left->setDepthAdd(fatherdepth);
|
|
|
|
} else {
|
|
|
|
// Zag zig
|
|
|
|
grandfather->setLeft(Right);
|
|
|
|
father->setRight(Left);
|
|
|
|
setLeft(father);
|
|
|
|
setRight(grandfather);
|
|
|
|
|
|
|
|
father->setDepth(-occdepth);
|
|
|
|
if (father->Right)
|
|
|
|
father->Right->setDepthAdd(occdepth);
|
|
|
|
grandfather->setDepth(-occdepth - fatherdepth);
|
|
|
|
if (grandfather->Left)
|
|
|
|
grandfather->Left->setDepthAdd(occdepth + fatherdepth);
|
|
|
|
}
|
|
|
|
} else {
|
|
|
|
if (father->Left == this) {
|
|
|
|
// Zig zag
|
|
|
|
grandfather->setRight(Left);
|
|
|
|
father->setLeft(Right);
|
|
|
|
setLeft(grandfather);
|
|
|
|
setRight(father);
|
|
|
|
|
|
|
|
father->setDepth(-occdepth);
|
|
|
|
if (father->Left)
|
|
|
|
father->Left->setDepthAdd(occdepth);
|
|
|
|
grandfather->setDepth(-occdepth - fatherdepth);
|
|
|
|
if (grandfather->Right)
|
|
|
|
grandfather->Right->setDepthAdd(occdepth + fatherdepth);
|
|
|
|
} else { // Zag Zag
|
|
|
|
grandfather->setRight(father->Left);
|
|
|
|
father->setRight(Left);
|
|
|
|
setLeft(father);
|
|
|
|
father->setLeft(grandfather);
|
|
|
|
|
|
|
|
father->setDepth(-occdepth);
|
|
|
|
if (father->Right)
|
|
|
|
father->Right->setDepthAdd(occdepth);
|
|
|
|
grandfather->setDepth(-fatherdepth);
|
|
|
|
if (grandfather->Right)
|
|
|
|
grandfather->Right->setDepthAdd(fatherdepth);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
// Might need one more rotate depending on greatgrandfather.
|
|
|
|
setParent(greatgrandfather);
|
|
|
|
if (greatgrandfather) {
|
|
|
|
if (greatgrandfather->Left == grandfather)
|
|
|
|
greatgrandfather->Left = this;
|
|
|
|
else
|
|
|
|
greatgrandfather->Right = this;
|
|
|
|
|
|
|
|
}
|
|
|
|
grandfather->recomputeMin();
|
|
|
|
father->recomputeMin();
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
// ETNode implementation
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
|
|
|
|
void ETNode::Split() {
|
|
|
|
ETOccurrence *right, *left;
|
|
|
|
ETOccurrence *rightmost = RightmostOcc;
|
|
|
|
ETOccurrence *parent;
|
|
|
|
|
|
|
|
// Update the occurrence tree first.
|
|
|
|
RightmostOcc->Splay();
|
|
|
|
|
|
|
|
// Find the leftmost occurrence in the rightmost subtree, then splay
|
|
|
|
// around it.
|
2006-01-09 07:58:01 +00:00
|
|
|
for (right = rightmost->Right; right->Left; right = right->Left);
|
2006-01-08 08:22:18 +00:00
|
|
|
|
|
|
|
right->Splay();
|
|
|
|
|
|
|
|
// Start splitting
|
|
|
|
right->Left->Parent = NULL;
|
|
|
|
parent = ParentOcc;
|
|
|
|
parent->Splay();
|
|
|
|
ParentOcc = NULL;
|
|
|
|
|
|
|
|
left = parent->Left;
|
|
|
|
parent->Right->Parent = NULL;
|
|
|
|
|
|
|
|
right->setLeft(left);
|
|
|
|
|
|
|
|
right->recomputeMin();
|
|
|
|
|
|
|
|
rightmost->Splay();
|
|
|
|
rightmost->Depth = 0;
|
|
|
|
rightmost->Min = 0;
|
|
|
|
|
|
|
|
delete parent;
|
|
|
|
|
|
|
|
// Now update *our* tree
|
|
|
|
|
|
|
|
if (Father->Son == this)
|
|
|
|
Father->Son = Right;
|
|
|
|
|
|
|
|
if (Father->Son == this)
|
|
|
|
Father->Son = NULL;
|
|
|
|
else {
|
|
|
|
Left->Right = Right;
|
|
|
|
Right->Left = Left;
|
|
|
|
}
|
|
|
|
Left = Right = NULL;
|
|
|
|
Father = NULL;
|
|
|
|
}
|
|
|
|
|
|
|
|
void ETNode::setFather(ETNode *NewFather) {
|
|
|
|
ETOccurrence *rightmost;
|
|
|
|
ETOccurrence *leftpart;
|
|
|
|
ETOccurrence *NewFatherOcc;
|
|
|
|
ETOccurrence *temp;
|
|
|
|
|
|
|
|
// First update the path in the splay tree
|
|
|
|
NewFatherOcc = new ETOccurrence(NewFather);
|
|
|
|
|
|
|
|
rightmost = NewFather->RightmostOcc;
|
|
|
|
rightmost->Splay();
|
|
|
|
|
|
|
|
leftpart = rightmost->Left;
|
|
|
|
|
|
|
|
temp = RightmostOcc;
|
|
|
|
temp->Splay();
|
|
|
|
|
|
|
|
NewFatherOcc->setLeft(leftpart);
|
|
|
|
NewFatherOcc->setRight(temp);
|
|
|
|
|
|
|
|
temp->Depth++;
|
|
|
|
temp->Min++;
|
|
|
|
NewFatherOcc->recomputeMin();
|
|
|
|
|
|
|
|
rightmost->setLeft(NewFatherOcc);
|
|
|
|
|
|
|
|
if (NewFatherOcc->Min + rightmost->Depth < rightmost->Min) {
|
|
|
|
rightmost->Min = NewFatherOcc->Min + rightmost->Depth;
|
|
|
|
rightmost->MinOccurrence = NewFatherOcc->MinOccurrence;
|
|
|
|
}
|
|
|
|
|
2006-03-14 19:41:45 +00:00
|
|
|
delete ParentOcc;
|
2006-01-08 08:22:18 +00:00
|
|
|
ParentOcc = NewFatherOcc;
|
|
|
|
|
|
|
|
// Update *our* tree
|
|
|
|
ETNode *left;
|
|
|
|
ETNode *right;
|
|
|
|
|
|
|
|
Father = NewFather;
|
|
|
|
right = Father->Son;
|
|
|
|
|
|
|
|
if (right)
|
|
|
|
left = right->Left;
|
|
|
|
else
|
|
|
|
left = right = this;
|
|
|
|
|
|
|
|
left->Right = this;
|
|
|
|
right->Left = this;
|
|
|
|
Left = left;
|
|
|
|
Right = right;
|
|
|
|
|
|
|
|
Father->Son = this;
|
|
|
|
}
|
|
|
|
|
|
|
|
bool ETNode::Below(ETNode *other) {
|
|
|
|
ETOccurrence *up = other->RightmostOcc;
|
|
|
|
ETOccurrence *down = RightmostOcc;
|
|
|
|
|
|
|
|
if (this == other)
|
|
|
|
return true;
|
|
|
|
|
|
|
|
up->Splay();
|
|
|
|
|
|
|
|
ETOccurrence *left, *right;
|
|
|
|
left = up->Left;
|
|
|
|
right = up->Right;
|
|
|
|
|
|
|
|
if (!left)
|
|
|
|
return false;
|
|
|
|
|
|
|
|
left->Parent = NULL;
|
|
|
|
|
|
|
|
if (right)
|
|
|
|
right->Parent = NULL;
|
|
|
|
|
|
|
|
down->Splay();
|
|
|
|
|
|
|
|
if (left == down || left->Parent != NULL) {
|
|
|
|
if (right)
|
|
|
|
right->Parent = up;
|
|
|
|
up->setLeft(down);
|
|
|
|
} else {
|
|
|
|
left->Parent = up;
|
|
|
|
|
|
|
|
// If the two occurrences are in different trees, put things
|
|
|
|
// back the way they were.
|
|
|
|
if (right && right->Parent != NULL)
|
|
|
|
up->setRight(down);
|
|
|
|
else
|
|
|
|
up->setRight(right);
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
|
|
|
|
if (down->Depth <= 0)
|
|
|
|
return false;
|
|
|
|
|
|
|
|
return !down->Right || down->Right->Min + down->Depth >= 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
ETNode *ETNode::NCA(ETNode *other) {
|
|
|
|
ETOccurrence *occ1 = RightmostOcc;
|
|
|
|
ETOccurrence *occ2 = other->RightmostOcc;
|
|
|
|
|
|
|
|
ETOccurrence *left, *right, *ret;
|
|
|
|
ETOccurrence *occmin;
|
|
|
|
int mindepth;
|
|
|
|
|
|
|
|
if (this == other)
|
|
|
|
return this;
|
|
|
|
|
|
|
|
occ1->Splay();
|
|
|
|
left = occ1->Left;
|
|
|
|
right = occ1->Right;
|
|
|
|
|
|
|
|
if (left)
|
|
|
|
left->Parent = NULL;
|
|
|
|
|
|
|
|
if (right)
|
|
|
|
right->Parent = NULL;
|
|
|
|
occ2->Splay();
|
|
|
|
|
|
|
|
if (left == occ2 || (left && left->Parent != NULL)) {
|
|
|
|
ret = occ2->Right;
|
|
|
|
|
|
|
|
occ1->setLeft(occ2);
|
|
|
|
if (right)
|
|
|
|
right->Parent = occ1;
|
|
|
|
} else {
|
|
|
|
ret = occ2->Left;
|
|
|
|
|
|
|
|
occ1->setRight(occ2);
|
|
|
|
if (left)
|
|
|
|
left->Parent = occ1;
|
|
|
|
}
|
|
|
|
|
|
|
|
if (occ2->Depth > 0) {
|
|
|
|
occmin = occ1;
|
|
|
|
mindepth = occ1->Depth;
|
|
|
|
} else {
|
|
|
|
occmin = occ2;
|
|
|
|
mindepth = occ2->Depth + occ1->Depth;
|
|
|
|
}
|
|
|
|
|
|
|
|
if (ret && ret->Min + occ1->Depth + occ2->Depth < mindepth)
|
|
|
|
return ret->MinOccurrence->OccFor;
|
|
|
|
else
|
|
|
|
return occmin->OccFor;
|
|
|
|
}
|
|
|
|
|
2006-09-22 01:05:33 +00:00
|
|
|
void ETNode::assignDFSNumber(int num) {
|
|
|
|
std::vector<ETNode *> workStack;
|
|
|
|
std::set<ETNode *> visitedNodes;
|
|
|
|
|
|
|
|
workStack.push_back(this);
|
|
|
|
visitedNodes.insert(this);
|
|
|
|
this->DFSNumIn = num++;
|
|
|
|
|
|
|
|
while (!workStack.empty()) {
|
|
|
|
ETNode *Node = workStack.back();
|
|
|
|
|
|
|
|
// If this is leaf node then set DFSNumOut and pop the stack
|
|
|
|
if (!Node->Son) {
|
|
|
|
Node->DFSNumOut = num++;
|
|
|
|
workStack.pop_back();
|
|
|
|
continue;
|
|
|
|
}
|
|
|
|
|
|
|
|
ETNode *son = Node->Son;
|
|
|
|
|
|
|
|
// Visit Node->Son first
|
|
|
|
if (visitedNodes.count(son) == 0) {
|
|
|
|
son->DFSNumIn = num++;
|
|
|
|
workStack.push_back(son);
|
|
|
|
visitedNodes.insert(son);
|
|
|
|
continue;
|
|
|
|
}
|
|
|
|
|
|
|
|
bool visitChild = false;
|
|
|
|
// Visit remaining children
|
|
|
|
for (ETNode *s = son->Right; s != son && !visitChild; s = s->Right) {
|
|
|
|
if (visitedNodes.count(s) == 0) {
|
|
|
|
visitChild = true;
|
|
|
|
s->DFSNumIn = num++;
|
|
|
|
workStack.push_back(s);
|
2006-09-22 01:07:57 +00:00
|
|
|
visitedNodes.insert(s);
|
2006-09-22 01:05:33 +00:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
if (!visitChild) {
|
|
|
|
// If we reach here means all children are visited
|
|
|
|
Node->DFSNumOut = num++;
|
|
|
|
workStack.pop_back();
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2006-01-08 08:22:18 +00:00
|
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
// ETForest implementation
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
|
2006-08-27 22:30:17 +00:00
|
|
|
static RegisterPass<ETForest>
|
2006-01-08 08:22:18 +00:00
|
|
|
D("etforest", "ET Forest Construction", true);
|
|
|
|
|
|
|
|
void ETForestBase::reset() {
|
|
|
|
for (ETMapType::iterator I = Nodes.begin(), E = Nodes.end(); I != E; ++I)
|
|
|
|
delete I->second;
|
|
|
|
Nodes.clear();
|
|
|
|
}
|
|
|
|
|
2006-01-14 20:55:09 +00:00
|
|
|
void ETForestBase::updateDFSNumbers()
|
|
|
|
{
|
|
|
|
int dfsnum = 0;
|
|
|
|
// Iterate over all nodes in depth first order.
|
|
|
|
for (unsigned i = 0, e = Roots.size(); i != e; ++i)
|
|
|
|
for (df_iterator<BasicBlock*> I = df_begin(Roots[i]),
|
|
|
|
E = df_end(Roots[i]); I != E; ++I) {
|
|
|
|
BasicBlock *BB = *I;
|
2007-04-08 01:02:12 +00:00
|
|
|
ETNode *ETN = getNode(BB);
|
|
|
|
if (ETN && !ETN->hasFather())
|
|
|
|
ETN->assignDFSNumber(dfsnum);
|
2006-01-14 20:55:09 +00:00
|
|
|
}
|
|
|
|
SlowQueries = 0;
|
|
|
|
DFSInfoValid = true;
|
|
|
|
}
|
|
|
|
|
2007-03-20 20:18:12 +00:00
|
|
|
// dominates - Return true if A dominates B. THis performs the
|
|
|
|
// special checks necessary if A and B are in the same basic block.
|
|
|
|
bool ETForestBase::dominates(Instruction *A, Instruction *B) {
|
|
|
|
BasicBlock *BBA = A->getParent(), *BBB = B->getParent();
|
|
|
|
if (BBA != BBB) return dominates(BBA, BBB);
|
|
|
|
|
2007-03-28 14:57:43 +00:00
|
|
|
// It is not possible to determine dominance between two PHI nodes
|
|
|
|
// based on their ordering.
|
|
|
|
if (isa<PHINode>(A) && isa<PHINode>(B))
|
|
|
|
return false;
|
|
|
|
|
2007-04-14 23:49:24 +00:00
|
|
|
// Loop through the basic block until we find A or B.
|
|
|
|
BasicBlock::iterator I = BBA->begin();
|
|
|
|
for (; &*I != A && &*I != B; ++I) /*empty*/;
|
|
|
|
|
2007-03-20 20:18:12 +00:00
|
|
|
if(!IsPostDominators) {
|
|
|
|
// A dominates B if it is found first in the basic block.
|
|
|
|
return &*I == A;
|
|
|
|
} else {
|
|
|
|
// A post-dominates B if B is found first in the basic block.
|
|
|
|
return &*I == B;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2007-04-09 04:07:36 +00:00
|
|
|
/// isReachableFromEntry - Return true if A is dominated by the entry
|
|
|
|
/// block of the function containing it.
|
|
|
|
const bool ETForestBase::isReachableFromEntry(BasicBlock* A) {
|
|
|
|
return dominates(&A->getParent()->getEntryBlock(), A);
|
|
|
|
}
|
|
|
|
|
2006-01-08 08:22:18 +00:00
|
|
|
ETNode *ETForest::getNodeForBlock(BasicBlock *BB) {
|
|
|
|
ETNode *&BBNode = Nodes[BB];
|
|
|
|
if (BBNode) return BBNode;
|
|
|
|
|
|
|
|
// Haven't calculated this node yet? Get or calculate the node for the
|
|
|
|
// immediate dominator.
|
2007-04-14 23:57:00 +00:00
|
|
|
DominatorTree::Node *node= getAnalysis<DominatorTree>().getNode(BB);
|
2006-01-08 08:22:18 +00:00
|
|
|
|
|
|
|
// If we are unreachable, we may not have an immediate dominator.
|
2007-04-14 23:57:00 +00:00
|
|
|
if (!node || !node->getIDom())
|
2006-01-08 08:22:18 +00:00
|
|
|
return BBNode = new ETNode(BB);
|
|
|
|
else {
|
2007-04-14 23:57:00 +00:00
|
|
|
ETNode *IDomNode = getNodeForBlock(node->getIDom()->getBlock());
|
2006-01-08 08:22:18 +00:00
|
|
|
|
|
|
|
// Add a new tree node for this BasicBlock, and link it as a child of
|
|
|
|
// IDomNode
|
|
|
|
BBNode = new ETNode(BB);
|
|
|
|
BBNode->setFather(IDomNode);
|
|
|
|
return BBNode;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2007-04-14 23:49:24 +00:00
|
|
|
void ETForest::calculate(const DominatorTree &DT) {
|
2006-01-08 08:22:18 +00:00
|
|
|
assert(Roots.size() == 1 && "ETForest should have 1 root block!");
|
|
|
|
BasicBlock *Root = Roots[0];
|
|
|
|
Nodes[Root] = new ETNode(Root); // Add a node for the root
|
|
|
|
|
|
|
|
Function *F = Root->getParent();
|
|
|
|
// Loop over all of the reachable blocks in the function...
|
2007-04-14 23:49:24 +00:00
|
|
|
for (Function::iterator I = F->begin(), E = F->end(); I != E; ++I) {
|
2007-04-14 23:57:00 +00:00
|
|
|
DominatorTree::Node* node = DT.getNode(I);
|
2007-04-14 23:49:24 +00:00
|
|
|
if (node && node->getIDom()) { // Reachable block.
|
2007-04-14 23:57:00 +00:00
|
|
|
BasicBlock* ImmDom = node->getIDom()->getBlock();
|
2006-01-08 08:22:18 +00:00
|
|
|
ETNode *&BBNode = Nodes[I];
|
|
|
|
if (!BBNode) { // Haven't calculated this node yet?
|
|
|
|
// Get or calculate the node for the immediate dominator
|
|
|
|
ETNode *IDomNode = getNodeForBlock(ImmDom);
|
|
|
|
|
|
|
|
// Add a new ETNode for this BasicBlock, and set it's parent
|
|
|
|
// to it's immediate dominator.
|
|
|
|
BBNode = new ETNode(I);
|
|
|
|
BBNode->setFather(IDomNode);
|
|
|
|
}
|
|
|
|
}
|
2007-04-14 23:57:00 +00:00
|
|
|
}
|
2006-01-08 08:22:18 +00:00
|
|
|
|
2006-01-14 20:55:09 +00:00
|
|
|
// Make sure we've got nodes around for every block
|
|
|
|
for (Function::iterator I = F->begin(), E = F->end(); I != E; ++I) {
|
|
|
|
ETNode *&BBNode = Nodes[I];
|
|
|
|
if (!BBNode)
|
|
|
|
BBNode = new ETNode(I);
|
2006-01-08 08:22:18 +00:00
|
|
|
}
|
2006-01-14 20:55:09 +00:00
|
|
|
|
|
|
|
updateDFSNumbers ();
|
2006-01-08 08:22:18 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
// ETForestBase Implementation
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
|
|
|
|
void ETForestBase::addNewBlock(BasicBlock *BB, BasicBlock *IDom) {
|
|
|
|
ETNode *&BBNode = Nodes[BB];
|
|
|
|
assert(!BBNode && "BasicBlock already in ET-Forest");
|
|
|
|
|
|
|
|
BBNode = new ETNode(BB);
|
|
|
|
BBNode->setFather(getNode(IDom));
|
|
|
|
DFSInfoValid = false;
|
|
|
|
}
|
|
|
|
|
|
|
|
void ETForestBase::setImmediateDominator(BasicBlock *BB, BasicBlock *newIDom) {
|
|
|
|
assert(getNode(BB) && "BasicBlock not in ET-Forest");
|
|
|
|
assert(getNode(newIDom) && "IDom not in ET-Forest");
|
|
|
|
|
|
|
|
ETNode *Node = getNode(BB);
|
|
|
|
if (Node->hasFather()) {
|
|
|
|
if (Node->getFather()->getData<BasicBlock>() == newIDom)
|
|
|
|
return;
|
|
|
|
Node->Split();
|
|
|
|
}
|
|
|
|
Node->setFather(getNode(newIDom));
|
|
|
|
DFSInfoValid= false;
|
|
|
|
}
|
|
|
|
|
|
|
|
void ETForestBase::print(std::ostream &o, const Module *) const {
|
|
|
|
o << "=============================--------------------------------\n";
|
|
|
|
o << "ET Forest:\n";
|
|
|
|
o << "DFS Info ";
|
|
|
|
if (DFSInfoValid)
|
|
|
|
o << "is";
|
|
|
|
else
|
|
|
|
o << "is not";
|
|
|
|
o << " up to date\n";
|
|
|
|
|
|
|
|
Function *F = getRoots()[0]->getParent();
|
|
|
|
for (Function::iterator I = F->begin(), E = F->end(); I != E; ++I) {
|
|
|
|
o << " DFS Numbers For Basic Block:";
|
|
|
|
WriteAsOperand(o, I, false);
|
|
|
|
o << " are:";
|
|
|
|
if (ETNode *EN = getNode(I)) {
|
|
|
|
o << "In: " << EN->getDFSNumIn();
|
|
|
|
o << " Out: " << EN->getDFSNumOut() << "\n";
|
|
|
|
} else {
|
|
|
|
o << "No associated ETNode";
|
|
|
|
}
|
|
|
|
o << "\n";
|
|
|
|
}
|
|
|
|
o << "\n";
|
|
|
|
}
|