//===- llvm/PassAnalysisSupport.h - Analysis Pass Support code --*- 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 stuff that is used to define and "use" Analysis Passes.
// This file is automatically #included by Pass.h, so:
//
// NO .CPP FILES SHOULD INCLUDE THIS FILE DIRECTLY
//
// Instead, #include Pass.h
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_PASS_ANALYSIS_SUPPORT_H
#define LLVM_PASS_ANALYSIS_SUPPORT_H
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/StringRef.h"
#include <vector>
namespace llvm {
//===----------------------------------------------------------------------===//
// AnalysisUsage - Represent the analysis usage information of a pass. This
// tracks analyses that the pass REQUIRES (must be available when the pass
// runs), REQUIRES TRANSITIVE (must be available throughout the lifetime of the
// pass), and analyses that the pass PRESERVES (the pass does not invalidate the
// results of these analyses). This information is provided by a pass to the
// Pass infrastructure through the getAnalysisUsage virtual function.
//
class AnalysisUsage {
public:
typedef SmallVector<AnalysisID, 32> VectorType;
private:
// Sets of analyses required and preserved by a pass
VectorType Required, RequiredTransitive, Preserved;
bool PreservesAll;
public:
AnalysisUsage() : PreservesAll(false) {}
// addRequired - Add the specified ID to the required set of the usage info
// for a pass.
//
AnalysisUsage &addRequiredID(const void *ID);
AnalysisUsage &addRequiredID(char &ID);
template<class PassClass>
AnalysisUsage &addRequired() {
return addRequiredID(PassClass::ID);
}
AnalysisUsage &addRequiredTransitiveID(char &ID);
template<class PassClass>
AnalysisUsage &addRequiredTransitive() {
return addRequiredTransitiveID(PassClass::ID);
}
// addPreserved - Add the specified ID to the set of analyses preserved by
// this pass
//
AnalysisUsage &addPreservedID(const void *ID) {
Preserved.push_back(ID);
return *this;
}
AnalysisUsage &addPreservedID(char &ID) {
Preserved.push_back(&ID);
return *this;
}
// addPreserved - Add the specified Pass class to the set of analyses
// preserved by this pass.
//
template<class PassClass>
AnalysisUsage &addPreserved() {
Preserved.push_back(&PassClass::ID);
return *this;
}
// addPreserved - Add the Pass with the specified argument string to the set
// of analyses preserved by this pass. If no such Pass exists, do nothing.
// This can be useful when a pass is trivially preserved, but may not be
// linked in. Be careful about spelling!
//
AnalysisUsage &addPreserved(StringRef Arg);
// setPreservesAll - Set by analyses that do not transform their input at all
void setPreservesAll() { PreservesAll = true; }
bool getPreservesAll() const { return PreservesAll; }
/// setPreservesCFG - This function should be called by the pass, iff they do
/// not:
///
/// 1. Add or remove basic blocks from the function
/// 2. Modify terminator instructions in any way.
///
/// This function annotates the AnalysisUsage info object to say that analyses
/// that only depend on the CFG are preserved by this pass.
///
void setPreservesCFG();
const VectorType &getRequiredSet() const { return Required; }
const VectorType &getRequiredTransitiveSet() const {
return RequiredTransitive;
}
const VectorType &getPreservedSet() const { return Preserved; }
};
//===----------------------------------------------------------------------===//
// AnalysisResolver - Simple interface used by Pass objects to pull all
// analysis information out of pass manager that is responsible to manage
// the pass.
//
class PMDataManager;
class AnalysisResolver {
private:
AnalysisResolver(); // DO NOT IMPLEMENT
public:
explicit AnalysisResolver(PMDataManager &P) : PM(P) { }
inline PMDataManager &getPMDataManager() { return PM; }
// Find pass that is implementing PI.
Pass *findImplPass(AnalysisID PI) {
Pass *ResultPass = 0;
for (unsigned i = 0; i < AnalysisImpls.size() ; ++i) {
if (AnalysisImpls[i].first == PI) {
ResultPass = AnalysisImpls[i].second;
break;
}
}
return ResultPass;
}
// Find pass that is implementing PI. Initialize pass for Function F.
Pass *findImplPass(Pass *P, AnalysisID PI, Function &F);
void addAnalysisImplsPair(AnalysisID PI, Pass *P) {
if (findImplPass(PI) == P)
return;
std::pair<AnalysisID, Pass*> pir = std::make_pair(PI,P);
AnalysisImpls.push_back(pir);
}
/// clearAnalysisImpls - Clear cache that is used to connect a pass to the
/// the analysis (PassInfo).
void clearAnalysisImpls() {
AnalysisImpls.clear();
}
// getAnalysisIfAvailable - Return analysis result or null if it doesn't exist
Pass *getAnalysisIfAvailable(AnalysisID ID, bool Direction) const;
private:
// AnalysisImpls - This keeps track of which passes implements the interfaces
// that are required by the current pass (to implement getAnalysis()).
std::vector<std::pair<AnalysisID, Pass*> > AnalysisImpls;
// PassManager that is used to resolve analysis info
PMDataManager &PM;
};
/// getAnalysisIfAvailable<AnalysisType>() - Subclasses use this function to
/// get analysis information that might be around, for example to update it.
/// This is different than getAnalysis in that it can fail (if the analysis
/// results haven't been computed), so should only be used if you can handle
/// the case when the analysis is not available. This method is often used by
/// transformation APIs to update analysis results for a pass automatically as
/// the transform is performed.
///
template<typename AnalysisType>
AnalysisType *Pass::getAnalysisIfAvailable() const {
assert(Resolver && "Pass not resident in a PassManager object!");
const void *PI = &AnalysisType::ID;
Pass *ResultPass = Resolver->getAnalysisIfAvailable(PI, true);
if (ResultPass == 0) return 0;
// Because the AnalysisType may not be a subclass of pass (for
// AnalysisGroups), we use getAdjustedAnalysisPointer here to potentially
// adjust the return pointer (because the class may multiply inherit, once
// from pass, once from AnalysisType).
return (AnalysisType*)ResultPass->getAdjustedAnalysisPointer(PI);
}
/// getAnalysis<AnalysisType>() - This function is used by subclasses to get
/// to the analysis information that they claim to use by overriding the
/// getAnalysisUsage function.
///
template<typename AnalysisType>
AnalysisType &Pass::getAnalysis() const {
assert(Resolver && "Pass has not been inserted into a PassManager object!");
return getAnalysisID<AnalysisType>(&AnalysisType::ID);
}
template<typename AnalysisType>
AnalysisType &Pass::getAnalysisID(AnalysisID PI) const {
assert(PI && "getAnalysis for unregistered pass!");
assert(Resolver&&"Pass has not been inserted into a PassManager object!");
// PI *must* appear in AnalysisImpls. Because the number of passes used
// should be a small number, we just do a linear search over a (dense)
// vector.
Pass *ResultPass = Resolver->findImplPass(PI);
assert (ResultPass &&
"getAnalysis*() called on an analysis that was not "
"'required' by pass!");
// Because the AnalysisType may not be a subclass of pass (for
// AnalysisGroups), we use getAdjustedAnalysisPointer here to potentially
// adjust the return pointer (because the class may multiply inherit, once
// from pass, once from AnalysisType).
return *(AnalysisType*)ResultPass->getAdjustedAnalysisPointer(PI);
}
/// getAnalysis<AnalysisType>() - This function is used by subclasses to get
/// to the analysis information that they claim to use by overriding the
/// getAnalysisUsage function.
///
template<typename AnalysisType>
AnalysisType &Pass::getAnalysis(Function &F) {
assert(Resolver &&"Pass has not been inserted into a PassManager object!");
return getAnalysisID<AnalysisType>(&AnalysisType::ID, F);
}
template<typename AnalysisType>
AnalysisType &Pass::getAnalysisID(AnalysisID PI, Function &F) {
assert(PI && "getAnalysis for unregistered pass!");
assert(Resolver && "Pass has not been inserted into a PassManager object!");
// PI *must* appear in AnalysisImpls. Because the number of passes used
// should be a small number, we just do a linear search over a (dense)
// vector.
Pass *ResultPass = Resolver->findImplPass(this, PI, F);
assert(ResultPass && "Unable to find requested analysis info");
// Because the AnalysisType may not be a subclass of pass (for
// AnalysisGroups), we use getAdjustedAnalysisPointer here to potentially
// adjust the return pointer (because the class may multiply inherit, once
// from pass, once from AnalysisType).
return *(AnalysisType*)ResultPass->getAdjustedAnalysisPointer(PI);
}
} // End llvm namespace
#endif