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
24 // No need to include Pass.h, we are being included by it!
26 //===----------------------------------------------------------------------===//
27 // AnalysisUsage - Represent the analysis usage information of a pass. This
28 // tracks analyses that the pass REQUIRES (must be available when the pass
29 // runs), REQUIRES TRANSITIVE (must be available throughout the lifetime of the
30 // pass), and analyses that the pass PRESERVES (the pass does not invalidate the
31 // results of these analyses). This information is provided by a pass to the
32 // Pass infrastructure through the getAnalysisUsage virtual function.
35 // Sets of analyses required and preserved by a pass
36 std::vector<AnalysisID> Required, RequiredTransitive, Preserved;
39 AnalysisUsage() : PreservesAll(false) {}
41 // addRequired - Add the specified ID to the required set of the usage info
44 AnalysisUsage &addRequiredID(AnalysisID ID) {
45 Required.push_back(ID);
48 template<class PassClass>
49 AnalysisUsage &addRequired() {
50 assert(Pass::getClassPassInfo<PassClass>() && "Pass class not registered!");
51 Required.push_back(Pass::getClassPassInfo<PassClass>());
55 template<class PassClass>
56 AnalysisUsage &addRequiredTransitive() {
57 AnalysisID ID = Pass::getClassPassInfo<PassClass>();
58 assert(ID && "Pass class not registered!");
59 Required.push_back(ID);
60 RequiredTransitive.push_back(ID);
64 // addPreserved - Add the specified ID to the set of analyses preserved by
67 AnalysisUsage &addPreservedID(AnalysisID ID) {
68 Preserved.push_back(ID);
72 template<class PassClass>
73 AnalysisUsage &addPreserved() {
74 assert(Pass::getClassPassInfo<PassClass>() && "Pass class not registered!");
75 Preserved.push_back(Pass::getClassPassInfo<PassClass>());
79 // setPreservesAll - Set by analyses that do not transform their input at all
80 void setPreservesAll() { PreservesAll = true; }
81 bool getPreservesAll() const { return PreservesAll; }
83 /// setPreservesCFG - This function should be called by the pass, iff they do
86 /// 1. Add or remove basic blocks from the function
87 /// 2. Modify terminator instructions in any way.
89 /// This function annotates the AnalysisUsage info object to say that analyses
90 /// that only depend on the CFG are preserved by this pass.
92 void setPreservesCFG();
94 const std::vector<AnalysisID> &getRequiredSet() const { return Required; }
95 const std::vector<AnalysisID> &getRequiredTransitiveSet() const {
96 return RequiredTransitive;
98 const std::vector<AnalysisID> &getPreservedSet() const { return Preserved; }
103 //===----------------------------------------------------------------------===//
104 // AnalysisResolver - Simple interface implemented by PassManager objects that
105 // is used to pull analysis information out of them.
107 struct AnalysisResolver {
108 virtual Pass *getAnalysisOrNullUp(AnalysisID ID) const = 0;
109 virtual Pass *getAnalysisOrNullDown(AnalysisID ID) const = 0;
110 virtual void addPass(ImmutablePass *IP, AnalysisUsage &AU) = 0;
111 Pass *getAnalysis(AnalysisID ID) const {
112 Pass *Result = getAnalysisOrNullUp(ID);
113 assert(Result && "Pass has an incorrect analysis uses set!");
117 // getAnalysisToUpdate - Return an analysis result or null if it doesn't exist
118 Pass *getAnalysisToUpdate(AnalysisID ID) const {
119 return getAnalysisOrNullUp(ID);
122 // Methods for introspecting into pass manager objects...
123 virtual unsigned getDepth() const = 0;
124 virtual unsigned getNumContainedPasses() const = 0;
125 virtual const Pass *getContainedPass(unsigned N) const = 0;
127 virtual void markPassUsed(AnalysisID P, Pass *User) = 0;
129 void startPass(Pass *P) {}
130 void endPass(Pass *P) {}
132 void setAnalysisResolver(Pass *P, AnalysisResolver *AR);
135 /// getAnalysisToUpdate<AnalysisType>() - This function is used by subclasses
136 /// to get to the analysis information that might be around that needs to be
137 /// updated. This is different than getAnalysis in that it can fail (ie the
138 /// analysis results haven't been computed), so should only be used if you
139 /// provide the capability to update an analysis that exists. This method is
140 /// often used by transformation APIs to update analysis results for a pass
141 /// automatically as the transform is performed.
143 template<typename AnalysisType>
144 AnalysisType *Pass::getAnalysisToUpdate() const {
145 assert(Resolver && "Pass not resident in a PassManager object!");
146 const PassInfo *PI = getClassPassInfo<AnalysisType>();
147 if (PI == 0) return 0;
148 return dynamic_cast<AnalysisType*>(Resolver->getAnalysisToUpdate(PI));
151 } // End llvm namespace