1 // llvm/Transforms/IPO/PassManagerBuilder.h - Build Standard Pass -*- C++ -*-=// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 // 9 // This file defines the PassManagerBuilder class, which is used to set up a 10 // "standard" optimization sequence suitable for languages like C and C++. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #ifndef LLVM_TRANSFORMS_IPO_PASSMANAGERBUILDER_H 15 #define LLVM_TRANSFORMS_IPO_PASSMANAGERBUILDER_H 16 17 #include <functional> 18 #include <memory> 19 #include <string> 20 #include <vector> 21 22 namespace llvm { 23 class ModuleSummaryIndex; 24 class Pass; 25 class TargetLibraryInfoImpl; 26 class TargetMachine; 27 28 // The old pass manager infrastructure is hidden in a legacy namespace now. 29 namespace legacy { 30 class FunctionPassManager; 31 class PassManagerBase; 32 } 33 34 /// PassManagerBuilder - This class is used to set up a standard optimization 35 /// sequence for languages like C and C++, allowing some APIs to customize the 36 /// pass sequence in various ways. A simple example of using it would be: 37 /// 38 /// PassManagerBuilder Builder; 39 /// Builder.OptLevel = 2; 40 /// Builder.populateFunctionPassManager(FPM); 41 /// Builder.populateModulePassManager(MPM); 42 /// 43 /// In addition to setting up the basic passes, PassManagerBuilder allows 44 /// frontends to vend a plugin API, where plugins are allowed to add extensions 45 /// to the default pass manager. They do this by specifying where in the pass 46 /// pipeline they want to be added, along with a callback function that adds 47 /// the pass(es). For example, a plugin that wanted to add a loop optimization 48 /// could do something like this: 49 /// 50 /// static void addMyLoopPass(const PMBuilder &Builder, PassManagerBase &PM) { 51 /// if (Builder.getOptLevel() > 2 && Builder.getOptSizeLevel() == 0) 52 /// PM.add(createMyAwesomePass()); 53 /// } 54 /// ... 55 /// Builder.addExtension(PassManagerBuilder::EP_LoopOptimizerEnd, 56 /// addMyLoopPass); 57 /// ... 58 class PassManagerBuilder { 59 public: 60 /// Extensions are passed to the builder itself (so they can see how it is 61 /// configured) as well as the pass manager to add stuff to. 62 typedef std::function<void(const PassManagerBuilder &Builder, 63 legacy::PassManagerBase &PM)> 64 ExtensionFn; 65 typedef int GlobalExtensionID; 66 67 enum ExtensionPointTy { 68 /// EP_EarlyAsPossible - This extension point allows adding passes before 69 /// any other transformations, allowing them to see the code as it is coming 70 /// out of the frontend. 71 EP_EarlyAsPossible, 72 73 /// EP_ModuleOptimizerEarly - This extension point allows adding passes 74 /// just before the main module-level optimization passes. 75 EP_ModuleOptimizerEarly, 76 77 /// EP_LoopOptimizerEnd - This extension point allows adding loop passes to 78 /// the end of the loop optimizer. 79 EP_LoopOptimizerEnd, 80 81 /// EP_ScalarOptimizerLate - This extension point allows adding optimization 82 /// passes after most of the main optimizations, but before the last 83 /// cleanup-ish optimizations. 84 EP_ScalarOptimizerLate, 85 86 /// EP_OptimizerLast -- This extension point allows adding passes that 87 /// run after everything else. 88 EP_OptimizerLast, 89 90 /// EP_VectorizerStart - This extension point allows adding optimization 91 /// passes before the vectorizer and other highly target specific 92 /// optimization passes are executed. 93 EP_VectorizerStart, 94 95 /// EP_EnabledOnOptLevel0 - This extension point allows adding passes that 96 /// should not be disabled by O0 optimization level. The passes will be 97 /// inserted after the inlining pass. 98 EP_EnabledOnOptLevel0, 99 100 /// EP_Peephole - This extension point allows adding passes that perform 101 /// peephole optimizations similar to the instruction combiner. These passes 102 /// will be inserted after each instance of the instruction combiner pass. 103 EP_Peephole, 104 105 /// EP_LateLoopOptimizations - This extension point allows adding late loop 106 /// canonicalization and simplification passes. This is the last point in 107 /// the loop optimization pipeline before loop deletion. Each pass added 108 /// here must be an instance of LoopPass. 109 /// This is the place to add passes that can remove loops, such as target- 110 /// specific loop idiom recognition. 111 EP_LateLoopOptimizations, 112 113 /// EP_CGSCCOptimizerLate - This extension point allows adding CallGraphSCC 114 /// passes at the end of the main CallGraphSCC passes and before any 115 /// function simplification passes run by CGPassManager. 116 EP_CGSCCOptimizerLate, 117 118 /// EP_FullLinkTimeOptimizationEarly - This extensions point allow adding 119 /// passes that 120 /// run at Link Time, before Full Link Time Optimization. 121 EP_FullLinkTimeOptimizationEarly, 122 123 /// EP_FullLinkTimeOptimizationLast - This extensions point allow adding 124 /// passes that 125 /// run at Link Time, after Full Link Time Optimization. 126 EP_FullLinkTimeOptimizationLast, 127 }; 128 129 /// The Optimization Level - Specify the basic optimization level. 130 /// 0 = -O0, 1 = -O1, 2 = -O2, 3 = -O3 131 unsigned OptLevel; 132 133 /// SizeLevel - How much we're optimizing for size. 134 /// 0 = none, 1 = -Os, 2 = -Oz 135 unsigned SizeLevel; 136 137 /// LibraryInfo - Specifies information about the runtime library for the 138 /// optimizer. If this is non-null, it is added to both the function and 139 /// per-module pass pipeline. 140 TargetLibraryInfoImpl *LibraryInfo; 141 142 /// Inliner - Specifies the inliner to use. If this is non-null, it is 143 /// added to the per-module passes. 144 Pass *Inliner; 145 146 /// The module summary index to use for exporting information from the 147 /// regular LTO phase, for example for the CFI and devirtualization type 148 /// tests. 149 ModuleSummaryIndex *ExportSummary = nullptr; 150 151 /// The module summary index to use for importing information to the 152 /// thin LTO backends, for example for the CFI and devirtualization type 153 /// tests. 154 const ModuleSummaryIndex *ImportSummary = nullptr; 155 156 bool DisableTailCalls; 157 bool DisableUnrollLoops; 158 bool SLPVectorize; 159 bool LoopVectorize; 160 bool LoopsInterleaved; 161 bool RerollLoops; 162 bool NewGVN; 163 bool DisableGVNLoadPRE; 164 bool ForgetAllSCEVInLoopUnroll; 165 bool VerifyInput; 166 bool VerifyOutput; 167 bool MergeFunctions; 168 bool PrepareForLTO; 169 bool PrepareForThinLTO; 170 bool PerformThinLTO; 171 bool DivergentTarget; 172 unsigned LicmMssaOptCap; 173 unsigned LicmMssaNoAccForPromotionCap; 174 175 /// Enable profile instrumentation pass. 176 bool EnablePGOInstrGen; 177 /// Enable profile context sensitive instrumentation pass. 178 bool EnablePGOCSInstrGen; 179 /// Enable profile context sensitive profile use pass. 180 bool EnablePGOCSInstrUse; 181 /// Profile data file name that the instrumentation will be written to. 182 std::string PGOInstrGen; 183 /// Path of the profile data file. 184 std::string PGOInstrUse; 185 /// Path of the sample Profile data file. 186 std::string PGOSampleUse; 187 188 private: 189 /// ExtensionList - This is list of all of the extensions that are registered. 190 std::vector<std::pair<ExtensionPointTy, ExtensionFn>> Extensions; 191 192 public: 193 PassManagerBuilder(); 194 ~PassManagerBuilder(); 195 /// Adds an extension that will be used by all PassManagerBuilder instances. 196 /// This is intended to be used by plugins, to register a set of 197 /// optimisations to run automatically. 198 /// 199 /// \returns A global extension identifier that can be used to remove the 200 /// extension. 201 static GlobalExtensionID addGlobalExtension(ExtensionPointTy Ty, 202 ExtensionFn Fn); 203 /// Removes an extension that was previously added using addGlobalExtension. 204 /// This is also intended to be used by plugins, to remove any extension that 205 /// was previously registered before being unloaded. 206 /// 207 /// \param ExtensionID Identifier of the extension to be removed. 208 static void removeGlobalExtension(GlobalExtensionID ExtensionID); 209 void addExtension(ExtensionPointTy Ty, ExtensionFn Fn); 210 211 private: 212 void addExtensionsToPM(ExtensionPointTy ETy, 213 legacy::PassManagerBase &PM) const; 214 void addInitialAliasAnalysisPasses(legacy::PassManagerBase &PM) const; 215 void addLTOOptimizationPasses(legacy::PassManagerBase &PM); 216 void addLateLTOOptimizationPasses(legacy::PassManagerBase &PM); 217 void addPGOInstrPasses(legacy::PassManagerBase &MPM, bool IsCS); 218 void addFunctionSimplificationPasses(legacy::PassManagerBase &MPM); 219 void addInstructionCombiningPass(legacy::PassManagerBase &MPM) const; 220 221 public: 222 /// populateFunctionPassManager - This fills in the function pass manager, 223 /// which is expected to be run on each function immediately as it is 224 /// generated. The idea is to reduce the size of the IR in memory. 225 void populateFunctionPassManager(legacy::FunctionPassManager &FPM); 226 227 /// populateModulePassManager - This sets up the primary pass manager. 228 void populateModulePassManager(legacy::PassManagerBase &MPM); 229 void populateLTOPassManager(legacy::PassManagerBase &PM); 230 void populateThinLTOPassManager(legacy::PassManagerBase &PM); 231 }; 232 233 /// Registers a function for adding a standard set of passes. This should be 234 /// used by optimizer plugins to allow all front ends to transparently use 235 /// them. Create a static instance of this class in your plugin, providing a 236 /// private function that the PassManagerBuilder can use to add your passes. 237 class RegisterStandardPasses { 238 PassManagerBuilder::GlobalExtensionID ExtensionID; 239 240 public: RegisterStandardPasses(PassManagerBuilder::ExtensionPointTy Ty,PassManagerBuilder::ExtensionFn Fn)241 RegisterStandardPasses(PassManagerBuilder::ExtensionPointTy Ty, 242 PassManagerBuilder::ExtensionFn Fn) { 243 ExtensionID = PassManagerBuilder::addGlobalExtension(Ty, std::move(Fn)); 244 } 245 ~RegisterStandardPasses()246 ~RegisterStandardPasses() { 247 // If the collection holding the global extensions is destroyed after the 248 // plugin is unloaded, the extension has to be removed here. Indeed, the 249 // destructor of the ExtensionFn may reference code in the plugin. 250 PassManagerBuilder::removeGlobalExtension(ExtensionID); 251 } 252 }; 253 254 } // end namespace llvm 255 #endif 256