llvm-6502/include/llvm/IR/Dominators.h
Cong Hou 1dd3d83c5e Add new constructors for LoopInfo/DominatorTree/BFI/BPI
Those new constructors make it more natural to construct an object for a function. For example, previously to build a LoopInfo for a function, we need four statements:

DominatorTree DT;
LoopInfo LI;
DT.recalculate(F);
LI.analyze(DT);

Now we only need one statement:

LoopInfo LI(DominatorTree(F));

http://reviews.llvm.org/D11274



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242486 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-16 23:23:35 +00:00

260 lines
7.5 KiB
C++

//===- Dominators.h - Dominator Info Calculation ----------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines the DominatorTree class, which provides fast and efficient
// dominance queries.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_IR_DOMINATORS_H
#define LLVM_IR_DOMINATORS_H
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/DepthFirstIterator.h"
#include "llvm/ADT/GraphTraits.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/IR/BasicBlock.h"
#include "llvm/IR/CFG.h"
#include "llvm/IR/Function.h"
#include "llvm/Pass.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/GenericDomTree.h"
#include "llvm/Support/raw_ostream.h"
#include <algorithm>
namespace llvm {
// FIXME: Replace this brittle forward declaration with the include of the new
// PassManager.h when doing so doesn't break the PassManagerBuilder.
template <typename IRUnitT> class AnalysisManager;
class PreservedAnalyses;
extern template class DomTreeNodeBase<BasicBlock>;
extern template class DominatorTreeBase<BasicBlock>;
extern template void Calculate<Function, BasicBlock *>(
DominatorTreeBase<GraphTraits<BasicBlock *>::NodeType> &DT, Function &F);
extern template void Calculate<Function, Inverse<BasicBlock *>>(
DominatorTreeBase<GraphTraits<Inverse<BasicBlock *>>::NodeType> &DT,
Function &F);
typedef DomTreeNodeBase<BasicBlock> DomTreeNode;
class BasicBlockEdge {
const BasicBlock *Start;
const BasicBlock *End;
public:
BasicBlockEdge(const BasicBlock *Start_, const BasicBlock *End_) :
Start(Start_), End(End_) { }
const BasicBlock *getStart() const {
return Start;
}
const BasicBlock *getEnd() const {
return End;
}
bool isSingleEdge() const;
};
/// \brief Concrete subclass of DominatorTreeBase that is used to compute a
/// normal dominator tree.
class DominatorTree : public DominatorTreeBase<BasicBlock> {
public:
typedef DominatorTreeBase<BasicBlock> Base;
DominatorTree() : DominatorTreeBase<BasicBlock>(false) {}
explicit DominatorTree(Function &F) : DominatorTreeBase<BasicBlock>(false) {
recalculate(F);
}
DominatorTree(DominatorTree &&Arg)
: Base(std::move(static_cast<Base &>(Arg))) {}
DominatorTree &operator=(DominatorTree &&RHS) {
Base::operator=(std::move(static_cast<Base &>(RHS)));
return *this;
}
/// \brief Returns *false* if the other dominator tree matches this dominator
/// tree.
inline bool compare(const DominatorTree &Other) const {
const DomTreeNode *R = getRootNode();
const DomTreeNode *OtherR = Other.getRootNode();
if (!R || !OtherR || R->getBlock() != OtherR->getBlock())
return true;
if (Base::compare(Other))
return true;
return false;
}
// Ensure base-class overloads are visible.
using Base::dominates;
/// \brief Return true if Def dominates a use in User.
///
/// This performs the special checks necessary if Def and User are in the same
/// basic block. Note that Def doesn't dominate a use in Def itself!
bool dominates(const Instruction *Def, const Use &U) const;
bool dominates(const Instruction *Def, const Instruction *User) const;
bool dominates(const Instruction *Def, const BasicBlock *BB) const;
bool dominates(const BasicBlockEdge &BBE, const Use &U) const;
bool dominates(const BasicBlockEdge &BBE, const BasicBlock *BB) const;
// Ensure base class overloads are visible.
using Base::isReachableFromEntry;
/// \brief Provide an overload for a Use.
bool isReachableFromEntry(const Use &U) const;
/// \brief Verify the correctness of the domtree by re-computing it.
///
/// This should only be used for debugging as it aborts the program if the
/// verification fails.
void verifyDomTree() const;
};
//===-------------------------------------
// DominatorTree GraphTraits specializations so the DominatorTree can be
// iterable by generic graph iterators.
template <> struct GraphTraits<DomTreeNode*> {
typedef DomTreeNode NodeType;
typedef NodeType::iterator ChildIteratorType;
static NodeType *getEntryNode(NodeType *N) {
return N;
}
static inline ChildIteratorType child_begin(NodeType *N) {
return N->begin();
}
static inline ChildIteratorType child_end(NodeType *N) {
return N->end();
}
typedef df_iterator<DomTreeNode*> nodes_iterator;
static nodes_iterator nodes_begin(DomTreeNode *N) {
return df_begin(getEntryNode(N));
}
static nodes_iterator nodes_end(DomTreeNode *N) {
return df_end(getEntryNode(N));
}
};
template <> struct GraphTraits<const DomTreeNode *> {
typedef const DomTreeNode NodeType;
typedef NodeType::const_iterator ChildIteratorType;
static NodeType *getEntryNode(NodeType *N) {
return N;
}
static inline ChildIteratorType child_begin(NodeType *N) {
return N->begin();
}
static inline ChildIteratorType child_end(NodeType *N) {
return N->end();
}
typedef df_iterator<const DomTreeNode *> nodes_iterator;
static nodes_iterator nodes_begin(const DomTreeNode *N) {
return df_begin(getEntryNode(N));
}
static nodes_iterator nodes_end(const DomTreeNode *N) {
return df_end(getEntryNode(N));
}
};
template <> struct GraphTraits<DominatorTree*>
: public GraphTraits<DomTreeNode*> {
static NodeType *getEntryNode(DominatorTree *DT) {
return DT->getRootNode();
}
static nodes_iterator nodes_begin(DominatorTree *N) {
return df_begin(getEntryNode(N));
}
static nodes_iterator nodes_end(DominatorTree *N) {
return df_end(getEntryNode(N));
}
};
/// \brief Analysis pass which computes a \c DominatorTree.
class DominatorTreeAnalysis {
public:
/// \brief Provide the result typedef for this analysis pass.
typedef DominatorTree Result;
/// \brief Opaque, unique identifier for this analysis pass.
static void *ID() { return (void *)&PassID; }
/// \brief Run the analysis pass over a function and produce a dominator tree.
DominatorTree run(Function &F);
/// \brief Provide access to a name for this pass for debugging purposes.
static StringRef name() { return "DominatorTreeAnalysis"; }
private:
static char PassID;
};
/// \brief Printer pass for the \c DominatorTree.
class DominatorTreePrinterPass {
raw_ostream &OS;
public:
explicit DominatorTreePrinterPass(raw_ostream &OS);
PreservedAnalyses run(Function &F, AnalysisManager<Function> *AM);
static StringRef name() { return "DominatorTreePrinterPass"; }
};
/// \brief Verifier pass for the \c DominatorTree.
struct DominatorTreeVerifierPass {
PreservedAnalyses run(Function &F, AnalysisManager<Function> *AM);
static StringRef name() { return "DominatorTreeVerifierPass"; }
};
/// \brief Legacy analysis pass which computes a \c DominatorTree.
class DominatorTreeWrapperPass : public FunctionPass {
DominatorTree DT;
public:
static char ID;
DominatorTreeWrapperPass() : FunctionPass(ID) {
initializeDominatorTreeWrapperPassPass(*PassRegistry::getPassRegistry());
}
DominatorTree &getDomTree() { return DT; }
const DominatorTree &getDomTree() const { return DT; }
bool runOnFunction(Function &F) override;
void verifyAnalysis() const override;
void getAnalysisUsage(AnalysisUsage &AU) const override {
AU.setPreservesAll();
}
void releaseMemory() override { DT.releaseMemory(); }
void print(raw_ostream &OS, const Module *M = nullptr) const override;
};
} // End llvm namespace
#endif