1 //===- llvm/PassAnalysisSupport.h - Analysis Pass Support code --*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by the LLVM research group and is distributed under
6 // the University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file defines stuff that is used to define and "use" Analysis Passes.
11 // This file is automatically #included by Pass.h, so:
13 // NO .CPP FILES SHOULD INCLUDE THIS FILE DIRECTLY
15 // Instead, #include Pass.h
17 //===----------------------------------------------------------------------===//
19 #ifndef LLVM_PASS_ANALYSIS_SUPPORT_H
20 #define LLVM_PASS_ANALYSIS_SUPPORT_H
26 // No need to include Pass.h, we are being included by it!
28 //===----------------------------------------------------------------------===//
29 // AnalysisUsage - Represent the analysis usage information of a pass. This
30 // tracks analyses that the pass REQUIRES (must be available when the pass
31 // runs), REQUIRES TRANSITIVE (must be available throughout the lifetime of the
32 // pass), and analyses that the pass PRESERVES (the pass does not invalidate the
33 // results of these analyses). This information is provided by a pass to the
34 // Pass infrastructure through the getAnalysisUsage virtual function.
37 // Sets of analyses required and preserved by a pass
38 std::vector<AnalysisID> Required, RequiredTransitive, Preserved;
41 AnalysisUsage() : PreservesAll(false) {}
43 // addRequired - Add the specified ID to the required set of the usage info
46 AnalysisUsage &addRequiredID(AnalysisID ID) {
47 Required.push_back(ID);
50 template<class PassClass>
51 AnalysisUsage &addRequired() {
52 assert(Pass::getClassPassInfo<PassClass>() && "Pass class not registered!");
53 Required.push_back(Pass::getClassPassInfo<PassClass>());
57 template<class PassClass>
58 AnalysisUsage &addRequiredTransitive() {
59 AnalysisID ID = Pass::getClassPassInfo<PassClass>();
60 assert(ID && "Pass class not registered!");
61 Required.push_back(ID);
62 RequiredTransitive.push_back(ID);
66 // addPreserved - Add the specified ID to the set of analyses preserved by
69 AnalysisUsage &addPreservedID(AnalysisID ID) {
70 Preserved.push_back(ID);
74 template<class PassClass>
75 AnalysisUsage &addPreserved() {
76 assert(Pass::getClassPassInfo<PassClass>() && "Pass class not registered!");
77 Preserved.push_back(Pass::getClassPassInfo<PassClass>());
81 // setPreservesAll - Set by analyses that do not transform their input at all
82 void setPreservesAll() { PreservesAll = true; }
83 bool getPreservesAll() const { return PreservesAll; }
85 /// setPreservesCFG - This function should be called by the pass, iff they do
88 /// 1. Add or remove basic blocks from the function
89 /// 2. Modify terminator instructions in any way.
91 /// This function annotates the AnalysisUsage info object to say that analyses
92 /// that only depend on the CFG are preserved by this pass.
94 void setPreservesCFG();
96 const std::vector<AnalysisID> &getRequiredSet() const { return Required; }
97 const std::vector<AnalysisID> &getRequiredTransitiveSet() const {
98 return RequiredTransitive;
100 const std::vector<AnalysisID> &getPreservedSet() const { return Preserved; }
103 //===----------------------------------------------------------------------===//
104 // AnalysisResolver - Simple interface used by Pass objects to pull all
105 // analysis information out of pass manager that is responsible to manage
109 class AnalysisResolver {
111 AnalysisResolver(); // DO NOT IMPLEMENT
114 explicit AnalysisResolver(PMDataManager &P) : PM(P) { }
116 inline PMDataManager &getPMDataManager() { return PM; }
118 // Find pass that is implementing PI.
119 Pass *findImplPass(const PassInfo *PI) {
120 Pass *ResultPass = 0;
121 for (unsigned i = 0; i < AnalysisImpls.size() ; ++i) {
122 if (AnalysisImpls[i].first == PI) {
123 ResultPass = AnalysisImpls[i].second;
130 // Find pass that is implementing PI. Initialize pass for Function F.
131 Pass *findImplPass(Pass *P, const PassInfo *PI, Function &F);
133 void addAnalysisImplsPair(const PassInfo *PI, Pass *P) {
134 std::pair<const PassInfo*, Pass*> pir = std::make_pair(PI,P);
135 AnalysisImpls.push_back(pir);
138 // getAnalysisToUpdate - Return an analysis result or null if it doesn't exist
139 Pass *getAnalysisToUpdate(AnalysisID ID, bool Direction) const;
141 // AnalysisImpls - This keeps track of which passes implements the interfaces
142 // that are required by the current pass (to implement getAnalysis()).
143 // NOTE : Remove AnalysisImpls from class Pass, when AnalysisResolver
144 // replaces AnalysisResolver
145 std::vector<std::pair<const PassInfo*, Pass*> > AnalysisImpls;
148 // PassManager that is used to resolve analysis info
152 /// getAnalysisToUpdate<AnalysisType>() - This function is used by subclasses
153 /// to get to the analysis information that might be around that needs to be
154 /// updated. This is different than getAnalysis in that it can fail (ie the
155 /// analysis results haven't been computed), so should only be used if you
156 /// provide the capability to update an analysis that exists. This method is
157 /// often used by transformation APIs to update analysis results for a pass
158 /// automatically as the transform is performed.
160 template<typename AnalysisType>
161 AnalysisType *Pass::getAnalysisToUpdate() const {
162 assert(Resolver && "Pass not resident in a PassManager object!");
164 const PassInfo *PI = getClassPassInfo<AnalysisType>();
165 if (PI == 0) return 0;
166 return dynamic_cast<AnalysisType*>
167 (Resolver->getAnalysisToUpdate(PI, true));
170 /// getAnalysis<AnalysisType>() - This function is used by subclasses to get
171 /// to the analysis information that they claim to use by overriding the
172 /// getAnalysisUsage function.
174 template<typename AnalysisType>
175 AnalysisType &Pass::getAnalysis() const {
176 assert(Resolver &&"Pass has not been inserted into a PassManager object!");
178 return getAnalysisID<AnalysisType>(getClassPassInfo<AnalysisType>());
181 template<typename AnalysisType>
182 AnalysisType &Pass::getAnalysisID(const PassInfo *PI) const {
183 assert(PI && "getAnalysis for unregistered pass!");
184 assert(Resolver&&"Pass has not been inserted into a PassManager object!");
185 // PI *must* appear in AnalysisImpls. Because the number of passes used
186 // should be a small number, we just do a linear search over a (dense)
188 Pass *ResultPass = Resolver->findImplPass(PI);
189 assert (ResultPass &&
190 "getAnalysis*() called on an analysis that was not "
191 "'required' by pass!");
193 // Because the AnalysisType may not be a subclass of pass (for
194 // AnalysisGroups), we must use dynamic_cast here to potentially adjust the
195 // return pointer (because the class may multiply inherit, once from pass,
196 // once from AnalysisType).
198 AnalysisType *Result = dynamic_cast<AnalysisType*>(ResultPass);
199 assert(Result && "Pass does not implement interface required!");
203 /// getAnalysis<AnalysisType>() - This function is used by subclasses to get
204 /// to the analysis information that they claim to use by overriding the
205 /// getAnalysisUsage function.
207 template<typename AnalysisType>
208 AnalysisType &Pass::getAnalysis(Function &F) {
209 assert(Resolver &&"Pass has not been inserted into a PassManager object!");
211 return getAnalysisID<AnalysisType>(getClassPassInfo<AnalysisType>(), F);
214 template<typename AnalysisType>
215 AnalysisType &Pass::getAnalysisID(const PassInfo *PI, Function &F) {
216 assert(PI && "getAnalysis for unregistered pass!");
217 assert(Resolver&&"Pass has not been inserted into a PassManager object!");
218 // PI *must* appear in AnalysisImpls. Because the number of passes used
219 // should be a small number, we just do a linear search over a (dense)
221 Pass *ResultPass = Resolver->findImplPass(this, PI, F);
222 assert (ResultPass &&
223 "getAnalysis*() called on an analysis that was not "
224 "'required' by pass!");
226 // Because the AnalysisType may not be a subclass of pass (for
227 // AnalysisGroups), we must use dynamic_cast here to potentially adjust the
228 // return pointer (because the class may multiply inherit, once from pass,
229 // once from AnalysisType).
231 AnalysisType *Result = dynamic_cast<AnalysisType*>(ResultPass);
232 assert(Result && "Pass does not implement interface required!");
236 } // End llvm namespace