include/llvm/Transforms/IPO/PassManagerBuilder.h

   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   enum ExtensionPointTy {
  66     /// EP_EarlyAsPossible - This extension point allows adding passes before
  67     /// any other transformations, allowing them to see the code as it is coming
  68     /// out of the frontend.
  69     EP_EarlyAsPossible,
  70
  71     /// EP_ModuleOptimizerEarly - This extension point allows adding passes
  72     /// just before the main module-level optimization passes.
  73     EP_ModuleOptimizerEarly,
  74
  75     /// EP_LoopOptimizerEnd - This extension point allows adding loop passes to
  76     /// the end of the loop optimizer.
  77     EP_LoopOptimizerEnd,
  78
  79     /// EP_ScalarOptimizerLate - This extension point allows adding optimization
  80     /// passes after most of the main optimizations, but before the last
  81     /// cleanup-ish optimizations.
  82     EP_ScalarOptimizerLate,
  83
  84     /// EP_OptimizerLast -- This extension point allows adding passes that
  85     /// run after everything else.
  86     EP_OptimizerLast,
  87
  88     /// EP_VectorizerStart - This extension point allows adding optimization
  89     /// passes before the vectorizer and other highly target specific
  90     /// optimization passes are executed.
  91     EP_VectorizerStart,
  92
  93     /// EP_EnabledOnOptLevel0 - This extension point allows adding passes that
  94     /// should not be disabled by O0 optimization level. The passes will be
  95     /// inserted after the inlining pass.
  96     EP_EnabledOnOptLevel0,
  97
  98     /// EP_Peephole - This extension point allows adding passes that perform
  99     /// peephole optimizations similar to the instruction combiner. These passes
 100     /// will be inserted after each instance of the instruction combiner pass.
 101     EP_Peephole,
 102
 103     /// EP_LateLoopOptimizations - This extension point allows adding late loop
 104     /// canonicalization and simplification passes. This is the last point in
 105     /// the loop optimization pipeline before loop deletion. Each pass added
 106     /// here must be an instance of LoopPass.
 107     /// This is the place to add passes that can remove loops, such as target-
 108     /// specific loop idiom recognition.
 109     EP_LateLoopOptimizations,
 110
 111     /// EP_CGSCCOptimizerLate - This extension point allows adding CallGraphSCC
 112     /// passes at the end of the main CallGraphSCC passes and before any
 113     /// function simplification passes run by CGPassManager.
 114     EP_CGSCCOptimizerLate,
 115
 116     /// EP_FullLinkTimeOptimizationEarly - This extensions point allow adding
 117     /// passes that
 118     /// run at Link Time, before Full Link Time Optimization.
 119     EP_FullLinkTimeOptimizationEarly,
 120
 121     /// EP_FullLinkTimeOptimizationLast - This extensions point allow adding
 122     /// passes that
 123     /// run at Link Time, after Full Link Time Optimization.
 124     EP_FullLinkTimeOptimizationLast,
 125   };
 126
 127   /// The Optimization Level - Specify the basic optimization level.
 128   ///    0 = -O0, 1 = -O1, 2 = -O2, 3 = -O3
 129   unsigned OptLevel;
 130
 131   /// SizeLevel - How much we're optimizing for size.
 132   ///    0 = none, 1 = -Os, 2 = -Oz
 133   unsigned SizeLevel;
 134
 135   /// LibraryInfo - Specifies information about the runtime library for the
 136   /// optimizer.  If this is non-null, it is added to both the function and
 137   /// per-module pass pipeline.
 138   TargetLibraryInfoImpl *LibraryInfo;
 139
 140   /// Inliner - Specifies the inliner to use.  If this is non-null, it is
 141   /// added to the per-module passes.
 142   Pass *Inliner;
 143
 144   /// The module summary index to use for exporting information from the
 145   /// regular LTO phase, for example for the CFI and devirtualization type
 146   /// tests.
 147   ModuleSummaryIndex *ExportSummary = nullptr;
 148
 149   /// The module summary index to use for importing information to the
 150   /// thin LTO backends, for example for the CFI and devirtualization type
 151   /// tests.
 152   const ModuleSummaryIndex *ImportSummary = nullptr;
 153
 154   bool DisableTailCalls;
 155   bool DisableUnrollLoops;
 156   bool SLPVectorize;
 157   bool LoopVectorize;
 158   bool LoopsInterleaved;
 159   bool RerollLoops;
 160   bool NewGVN;
 161   bool DisableGVNLoadPRE;
 162   bool ForgetAllSCEVInLoopUnroll;
 163   bool VerifyInput;
 164   bool VerifyOutput;
 165   bool MergeFunctions;
 166   bool PrepareForLTO;
 167   bool PrepareForThinLTO;
 168   bool PerformThinLTO;
 169   bool DivergentTarget;
 170   unsigned LicmMssaOptCap;
 171   unsigned LicmMssaNoAccForPromotionCap;
 172
 173   /// Enable profile instrumentation pass.
 174   bool EnablePGOInstrGen;
 175   /// Enable profile context sensitive instrumentation pass.
 176   bool EnablePGOCSInstrGen;
 177   /// Enable profile context sensitive profile use pass.
 178   bool EnablePGOCSInstrUse;
 179   /// Profile data file name that the instrumentation will be written to.
 180   std::string PGOInstrGen;
 181   /// Path of the profile data file.
 182   std::string PGOInstrUse;
 183   /// Path of the sample Profile data file.
 184   std::string PGOSampleUse;
 185
 186 private:
 187   /// ExtensionList - This is list of all of the extensions that are registered.
 188   std::vector<std::pair<ExtensionPointTy, ExtensionFn>> Extensions;
 189
 190 public:
 191   PassManagerBuilder();
 192   ~PassManagerBuilder();
 193   /// Adds an extension that will be used by all PassManagerBuilder instances.
 194   /// This is intended to be used by plugins, to register a set of
 195   /// optimisations to run automatically.
 196   static void addGlobalExtension(ExtensionPointTy Ty, ExtensionFn Fn);
 197   void addExtension(ExtensionPointTy Ty, ExtensionFn Fn);
 198
 199 private:
 200   void addExtensionsToPM(ExtensionPointTy ETy,
 201                          legacy::PassManagerBase &PM) const;
 202   void addInitialAliasAnalysisPasses(legacy::PassManagerBase &PM) const;
 203   void addLTOOptimizationPasses(legacy::PassManagerBase &PM);
 204   void addLateLTOOptimizationPasses(legacy::PassManagerBase &PM);
 205   void addPGOInstrPasses(legacy::PassManagerBase &MPM, bool IsCS);
 206   void addFunctionSimplificationPasses(legacy::PassManagerBase &MPM);
 207   void addInstructionCombiningPass(legacy::PassManagerBase &MPM) const;
 208
 209 public:
 210   /// populateFunctionPassManager - This fills in the function pass manager,
 211   /// which is expected to be run on each function immediately as it is
 212   /// generated.  The idea is to reduce the size of the IR in memory.
 213   void populateFunctionPassManager(legacy::FunctionPassManager &FPM);
 214
 215   /// populateModulePassManager - This sets up the primary pass manager.
 216   void populateModulePassManager(legacy::PassManagerBase &MPM);
 217   void populateLTOPassManager(legacy::PassManagerBase &PM);
 218   void populateThinLTOPassManager(legacy::PassManagerBase &PM);
 219 };
 220
 221 /// Registers a function for adding a standard set of passes.  This should be
 222 /// used by optimizer plugins to allow all front ends to transparently use
 223 /// them.  Create a static instance of this class in your plugin, providing a
 224 /// private function that the PassManagerBuilder can use to add your passes.
 225 struct RegisterStandardPasses {
 226   RegisterStandardPasses(PassManagerBuilder::ExtensionPointTy Ty,
 227                          PassManagerBuilder::ExtensionFn Fn) {
 228     PassManagerBuilder::addGlobalExtension(Ty, std::move(Fn));
 229   }
 230 };
 231
 232 } // end namespace llvm
 233 #endif