1 //===- CGSCCPassManager.h - Call graph pass management ----------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
11 /// This header provides classes for managing passes over SCCs of the call
12 /// graph. These passes form an important component of LLVM's interprocedural
13 /// optimizations. Because they operate on the SCCs of the call graph, and they
14 /// traverse the graph in post order, they can effectively do pair-wise
15 /// interprocedural optimizations for all call edges in the program. At each
16 /// call site edge, the callee has already been optimized as much as is
17 /// possible. This in turn allows very accurate analysis of it for IPO.
19 //===----------------------------------------------------------------------===//
21 #ifndef LLVM_ANALYSIS_CGSCCPASSMANAGER_H
22 #define LLVM_ANALYSIS_CGSCCPASSMANAGER_H
24 #include "llvm/Analysis/LazyCallGraph.h"
25 #include "llvm/IR/PassManager.h"
29 extern template class PassManager<LazyCallGraph::SCC>;
30 /// \brief The CGSCC pass manager.
32 /// See the documentation for the PassManager template for details. It runs
33 /// a sequency of SCC passes over each SCC that the manager is run over. This
34 /// typedef serves as a convenient way to refer to this construct.
35 typedef PassManager<LazyCallGraph::SCC> CGSCCPassManager;
37 extern template class AnalysisManager<LazyCallGraph::SCC>;
38 /// \brief The CGSCC analysis manager.
40 /// See the documentation for the AnalysisManager template for detail
41 /// documentation. This typedef serves as a convenient way to refer to this
42 /// construct in the adaptors and proxies used to integrate this into the larger
43 /// pass manager infrastructure.
44 typedef AnalysisManager<LazyCallGraph::SCC> CGSCCAnalysisManager;
46 extern template class InnerAnalysisManagerProxy<CGSCCAnalysisManager, Module>;
47 /// A proxy from a \c CGSCCAnalysisManager to a \c Module.
48 typedef InnerAnalysisManagerProxy<CGSCCAnalysisManager, Module>
49 CGSCCAnalysisManagerModuleProxy;
51 extern template class OuterAnalysisManagerProxy<ModuleAnalysisManager,
53 /// A proxy from a \c ModuleAnalysisManager to an \c SCC.
54 typedef OuterAnalysisManagerProxy<ModuleAnalysisManager, LazyCallGraph::SCC>
55 ModuleAnalysisManagerCGSCCProxy;
57 /// \brief The core module pass which does a post-order walk of the SCCs and
58 /// runs a CGSCC pass over each one.
60 /// Designed to allow composition of a CGSCCPass(Manager) and
61 /// a ModulePassManager. Note that this pass must be run with a module analysis
62 /// manager as it uses the LazyCallGraph analysis. It will also run the
63 /// \c CGSCCAnalysisManagerModuleProxy analysis prior to running the CGSCC
64 /// pass over the module to enable a \c FunctionAnalysisManager to be used
65 /// within this run safely.
66 template <typename CGSCCPassT>
67 class ModuleToPostOrderCGSCCPassAdaptor
68 : public PassInfoMixin<ModuleToPostOrderCGSCCPassAdaptor<CGSCCPassT>> {
70 explicit ModuleToPostOrderCGSCCPassAdaptor(CGSCCPassT Pass, bool DebugLogging = false)
71 : Pass(std::move(Pass)), DebugLogging(DebugLogging) {}
72 // We have to explicitly define all the special member functions because MSVC
73 // refuses to generate them.
74 ModuleToPostOrderCGSCCPassAdaptor(
75 const ModuleToPostOrderCGSCCPassAdaptor &Arg)
76 : Pass(Arg.Pass), DebugLogging(Arg.DebugLogging) {}
77 ModuleToPostOrderCGSCCPassAdaptor(ModuleToPostOrderCGSCCPassAdaptor &&Arg)
78 : Pass(std::move(Arg.Pass)), DebugLogging(Arg.DebugLogging) {}
79 friend void swap(ModuleToPostOrderCGSCCPassAdaptor &LHS,
80 ModuleToPostOrderCGSCCPassAdaptor &RHS) {
82 swap(LHS.Pass, RHS.Pass);
83 swap(LHS.DebugLogging, RHS.DebugLogging);
85 ModuleToPostOrderCGSCCPassAdaptor &
86 operator=(ModuleToPostOrderCGSCCPassAdaptor RHS) {
91 /// \brief Runs the CGSCC pass across every SCC in the module.
92 PreservedAnalyses run(Module &M, ModuleAnalysisManager &AM) {
93 // Setup the CGSCC analysis manager from its proxy.
94 CGSCCAnalysisManager &CGAM =
95 AM.getResult<CGSCCAnalysisManagerModuleProxy>(M).getManager();
97 // Get the call graph for this module.
98 LazyCallGraph &CG = AM.getResult<LazyCallGraphAnalysis>(M);
100 PreservedAnalyses PA = PreservedAnalyses::all();
101 for (LazyCallGraph::RefSCC &RC : CG.postorder_ref_sccs()) {
103 dbgs() << "Running an SCC pass across the RefSCC: " << RC << "\n";
105 for (LazyCallGraph::SCC &C : RC) {
106 PreservedAnalyses PassPA = Pass.run(C, CGAM);
108 // We know that the CGSCC pass couldn't have invalidated any other
109 // SCC's analyses (that's the contract of a CGSCC pass), so
110 // directly handle the CGSCC analysis manager's invalidation here. We
111 // also update the preserved set of analyses to reflect that invalidated
112 // analyses are now safe to preserve.
113 // FIXME: This isn't quite correct. We need to handle the case where the
114 // pass updated the CG, particularly some child of the current SCC, and
115 // invalidate its analyses.
116 PassPA = CGAM.invalidate(C, std::move(PassPA));
118 // Then intersect the preserved set so that invalidation of module
119 // analyses will eventually occur when the module pass completes.
120 PA.intersect(std::move(PassPA));
124 // By definition we preserve the proxy. This precludes *any* invalidation
125 // of CGSCC analyses by the proxy, but that's OK because we've taken
126 // care to invalidate analyses in the CGSCC analysis manager
127 // incrementally above.
128 PA.preserve<CGSCCAnalysisManagerModuleProxy>();
137 /// \brief A function to deduce a function pass type and wrap it in the
138 /// templated adaptor.
139 template <typename CGSCCPassT>
140 ModuleToPostOrderCGSCCPassAdaptor<CGSCCPassT>
141 createModuleToPostOrderCGSCCPassAdaptor(CGSCCPassT Pass, bool DebugLogging = false) {
142 return ModuleToPostOrderCGSCCPassAdaptor<CGSCCPassT>(std::move(Pass), DebugLogging);
145 extern template class InnerAnalysisManagerProxy<FunctionAnalysisManager,
147 /// A proxy from a \c FunctionAnalysisManager to an \c SCC.
148 typedef InnerAnalysisManagerProxy<FunctionAnalysisManager, LazyCallGraph::SCC>
149 FunctionAnalysisManagerCGSCCProxy;
151 extern template class OuterAnalysisManagerProxy<CGSCCAnalysisManager, Function>;
152 /// A proxy from a \c CGSCCAnalysisManager to a \c Function.
153 typedef OuterAnalysisManagerProxy<CGSCCAnalysisManager, Function>
154 CGSCCAnalysisManagerFunctionProxy;
156 /// \brief Adaptor that maps from a SCC to its functions.
158 /// Designed to allow composition of a FunctionPass(Manager) and
159 /// a CGSCCPassManager. Note that if this pass is constructed with a pointer
160 /// to a \c CGSCCAnalysisManager it will run the
161 /// \c FunctionAnalysisManagerCGSCCProxy analysis prior to running the function
162 /// pass over the SCC to enable a \c FunctionAnalysisManager to be used
163 /// within this run safely.
164 template <typename FunctionPassT>
165 class CGSCCToFunctionPassAdaptor
166 : public PassInfoMixin<CGSCCToFunctionPassAdaptor<FunctionPassT>> {
168 explicit CGSCCToFunctionPassAdaptor(FunctionPassT Pass, bool DebugLogging = false)
169 : Pass(std::move(Pass)), DebugLogging(DebugLogging) {}
170 // We have to explicitly define all the special member functions because MSVC
171 // refuses to generate them.
172 CGSCCToFunctionPassAdaptor(const CGSCCToFunctionPassAdaptor &Arg)
173 : Pass(Arg.Pass), DebugLogging(Arg.DebugLogging) {}
174 CGSCCToFunctionPassAdaptor(CGSCCToFunctionPassAdaptor &&Arg)
175 : Pass(std::move(Arg.Pass)), DebugLogging(Arg.DebugLogging) {}
176 friend void swap(CGSCCToFunctionPassAdaptor &LHS,
177 CGSCCToFunctionPassAdaptor &RHS) {
179 swap(LHS.Pass, RHS.Pass);
180 swap(LHS.DebugLogging, RHS.DebugLogging);
182 CGSCCToFunctionPassAdaptor &operator=(CGSCCToFunctionPassAdaptor RHS) {
187 /// \brief Runs the function pass across every function in the module.
188 PreservedAnalyses run(LazyCallGraph::SCC &C, CGSCCAnalysisManager &AM) {
189 // Setup the function analysis manager from its proxy.
190 FunctionAnalysisManager &FAM =
191 AM.getResult<FunctionAnalysisManagerCGSCCProxy>(C).getManager();
194 dbgs() << "Running function passes across an SCC: " << C << "\n";
196 PreservedAnalyses PA = PreservedAnalyses::all();
197 for (LazyCallGraph::Node &N : C) {
198 PreservedAnalyses PassPA = Pass.run(N.getFunction(), FAM);
200 // We know that the function pass couldn't have invalidated any other
201 // function's analyses (that's the contract of a function pass), so
202 // directly handle the function analysis manager's invalidation here.
203 // Also, update the preserved analyses to reflect that once invalidated
204 // these can again be preserved.
205 PassPA = FAM.invalidate(N.getFunction(), std::move(PassPA));
207 // Then intersect the preserved set so that invalidation of module
208 // analyses will eventually occur when the module pass completes.
209 PA.intersect(std::move(PassPA));
212 // By definition we preserve the proxy. This precludes *any* invalidation
213 // of function analyses by the proxy, but that's OK because we've taken
214 // care to invalidate analyses in the function analysis manager
215 // incrementally above.
216 // FIXME: We need to update the call graph here to account for any deleted
218 PA.preserve<FunctionAnalysisManagerCGSCCProxy>();
227 /// \brief A function to deduce a function pass type and wrap it in the
228 /// templated adaptor.
229 template <typename FunctionPassT>
230 CGSCCToFunctionPassAdaptor<FunctionPassT>
231 createCGSCCToFunctionPassAdaptor(FunctionPassT Pass, bool DebugLogging = false) {
232 return CGSCCToFunctionPassAdaptor<FunctionPassT>(std::move(Pass),