llvm-6502/include/llvm/Analysis/PostDominators.h
2006-03-20 19:32:48 +00:00

146 lines
4.6 KiB
C++

//=- llvm/Analysis/PostDominators.h - Post Dominator Calculation-*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file exposes interfaces to post dominance information.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_ANALYSIS_POST_DOMINATORS_H
#define LLVM_ANALYSIS_POST_DOMINATORS_H
#include "llvm/Analysis/Dominators.h"
namespace llvm {
//===-------------------------------------
/// ImmediatePostDominators Class - Concrete subclass of ImmediateDominatorsBase
/// that is used to compute a normal immediate dominator set.
///
struct ImmediatePostDominators : public ImmediateDominatorsBase {
ImmediatePostDominators() : ImmediateDominatorsBase(false) {}
virtual bool runOnFunction(Function &F);
virtual void getAnalysisUsage(AnalysisUsage &AU) const {
AU.setPreservesAll();
}
private:
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);
};
/// 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 simply provides a dominator set
///
virtual void getAnalysisUsage(AnalysisUsage &AU) const {
AU.addRequired<ImmediatePostDominators>();
AU.setPreservesAll();
}
// stub - dummy function, just ignore it
static void stub();
};
/// PostDominatorTree Class - Concrete subclass of DominatorTree that is used to
/// compute the a post-dominator tree.
///
struct PostDominatorTree : public DominatorTreeBase {
PostDominatorTree() : DominatorTreeBase(true) {}
virtual bool runOnFunction(Function &F) {
reset(); // Reset from the last time we were run...
ImmediatePostDominators &IPD = getAnalysis<ImmediatePostDominators>();
Roots = IPD.getRoots();
calculate(IPD);
return false;
}
virtual void getAnalysisUsage(AnalysisUsage &AU) const {
AU.setPreservesAll();
AU.addRequired<ImmediatePostDominators>();
}
private:
void calculate(const ImmediatePostDominators &IPD);
Node *getNodeForBlock(BasicBlock *BB);
};
/// 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<ImmediatePostDominators>();
}
virtual bool runOnFunction(Function &F) {
reset(); // Reset from the last time we were run...
ImmediatePostDominators &ID = getAnalysis<ImmediatePostDominators>();
Roots = ID.getRoots();
calculate(ID);
return false;
}
void calculate(const ImmediatePostDominators &ID);
ETNode *getNodeForBlock(BasicBlock *BB);
};
/// PostDominanceFrontier Class - Concrete subclass of DominanceFrontier that is
/// used to compute the a post-dominance frontier.
///
struct PostDominanceFrontier : public DominanceFrontierBase {
PostDominanceFrontier() : DominanceFrontierBase(true) {}
virtual bool runOnFunction(Function &) {
Frontiers.clear();
PostDominatorTree &DT = getAnalysis<PostDominatorTree>();
Roots = DT.getRoots();
if (const DominatorTree::Node *Root = DT.getRootNode())
calculate(DT, Root);
return false;
}
virtual void getAnalysisUsage(AnalysisUsage &AU) const {
AU.setPreservesAll();
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
#endif