llvm/lib/IR/PassManager.cpp

   1 //===- PassManager.cpp - Infrastructure for managing & running IR passes --===//
   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 #include "llvm/IR/PassManager.h"
  10 #include "llvm/ADT/DenseMapInfo.h"
  11 #include "llvm/IR/PassManagerImpl.h"
  12 #include <optional>
  13
  14 using namespace llvm;
  15
  16 namespace llvm {
  17 // Explicit template instantiations and specialization defininitions for core
  18 // template typedefs.
  19 template class AllAnalysesOn<Module>;
  20 template class AllAnalysesOn<Function>;
  21 template class PassManager<Module>;
  22 template class PassManager<Function>;
  23 template class AnalysisManager<Module>;
  24 template class AnalysisManager<Function>;
  25 template class InnerAnalysisManagerProxy<FunctionAnalysisManager, Module>;
  26 template class OuterAnalysisManagerProxy<ModuleAnalysisManager, Function>;
  27
  28 template <>
  29 bool FunctionAnalysisManagerModuleProxy::Result::invalidate(
  30     Module &M, const PreservedAnalyses &PA,
  31     ModuleAnalysisManager::Invalidator &Inv) {
  32   // If literally everything is preserved, we're done.
  33   if (PA.areAllPreserved())
  34     return false; // This is still a valid proxy.
  35
  36   // If this proxy isn't marked as preserved, then even if the result remains
  37   // valid, the key itself may no longer be valid, so we clear everything.
  38   //
  39   // Note that in order to preserve this proxy, a module pass must ensure that
  40   // the FAM has been completely updated to handle the deletion of functions.
  41   // Specifically, any FAM-cached results for those functions need to have been
  42   // forcibly cleared. When preserved, this proxy will only invalidate results
  43   // cached on functions *still in the module* at the end of the module pass.
  44   auto PAC = PA.getChecker<FunctionAnalysisManagerModuleProxy>();
  45   if (!PAC.preserved() && !PAC.preservedSet<AllAnalysesOn<Module>>()) {
  46     InnerAM->clear();
  47     return true;
  48   }
  49
  50   // Directly check if the relevant set is preserved.
  51   bool AreFunctionAnalysesPreserved =
  52       PA.allAnalysesInSetPreserved<AllAnalysesOn<Function>>();
  53
  54   // Now walk all the functions to see if any inner analysis invalidation is
  55   // necessary.
  56   for (Function &F : M) {
  57     std::optional<PreservedAnalyses> FunctionPA;
  58
  59     // Check to see whether the preserved set needs to be pruned based on
  60     // module-level analysis invalidation that triggers deferred invalidation
  61     // registered with the outer analysis manager proxy for this function.
  62     if (auto *OuterProxy =
  63             InnerAM->getCachedResult<ModuleAnalysisManagerFunctionProxy>(F))
  64       for (const auto &OuterInvalidationPair :
  65            OuterProxy->getOuterInvalidations()) {
  66         AnalysisKey *OuterAnalysisID = OuterInvalidationPair.first;
  67         const auto &InnerAnalysisIDs = OuterInvalidationPair.second;
  68         if (Inv.invalidate(OuterAnalysisID, M, PA)) {
  69           if (!FunctionPA)
  70             FunctionPA = PA;
  71           for (AnalysisKey *InnerAnalysisID : InnerAnalysisIDs)
  72             FunctionPA->abandon(InnerAnalysisID);
  73         }
  74       }
  75
  76     // Check if we needed a custom PA set, and if so we'll need to run the
  77     // inner invalidation.
  78     if (FunctionPA) {
  79       InnerAM->invalidate(F, *FunctionPA);
  80       continue;
  81     }
  82
  83     // Otherwise we only need to do invalidation if the original PA set didn't
  84     // preserve all function analyses.
  85     if (!AreFunctionAnalysesPreserved)
  86       InnerAM->invalidate(F, PA);
  87   }
  88
  89   // Return false to indicate that this result is still a valid proxy.
  90   return false;
  91 }
  92 } // namespace llvm
  93
  94 void ModuleToFunctionPassAdaptor::printPipeline(
  95     raw_ostream &OS, function_ref<StringRef(StringRef)> MapClassName2PassName) {
  96   OS << "function";
  97   if (EagerlyInvalidate)
  98     OS << "<eager-inv>";
  99   OS << '(';
 100   Pass->printPipeline(OS, MapClassName2PassName);
 101   OS << ')';
 102 }
 103
 104 PreservedAnalyses ModuleToFunctionPassAdaptor::run(Module &M,
 105                                                    ModuleAnalysisManager &AM) {
 106   FunctionAnalysisManager &FAM =
 107       AM.getResult<FunctionAnalysisManagerModuleProxy>(M).getManager();
 108
 109   // Request PassInstrumentation from analysis manager, will use it to run
 110   // instrumenting callbacks for the passes later.
 111   PassInstrumentation PI = AM.getResult<PassInstrumentationAnalysis>(M);
 112
 113   PreservedAnalyses PA = PreservedAnalyses::all();
 114   for (Function &F : M) {
 115     if (F.isDeclaration())
 116       continue;
 117
 118     // Check the PassInstrumentation's BeforePass callbacks before running the
 119     // pass, skip its execution completely if asked to (callback returns
 120     // false).
 121     if (!PI.runBeforePass<Function>(*Pass, F))
 122       continue;
 123
 124     PreservedAnalyses PassPA = Pass->run(F, FAM);
 125
 126     // We know that the function pass couldn't have invalidated any other
 127     // function's analyses (that's the contract of a function pass), so
 128     // directly handle the function analysis manager's invalidation here.
 129     FAM.invalidate(F, EagerlyInvalidate ? PreservedAnalyses::none() : PassPA);
 130
 131     PI.runAfterPass(*Pass, F, PassPA);
 132
 133     // Then intersect the preserved set so that invalidation of module
 134     // analyses will eventually occur when the module pass completes.
 135     PA.intersect(std::move(PassPA));
 136   }
 137
 138   // The FunctionAnalysisManagerModuleProxy is preserved because (we assume)
 139   // the function passes we ran didn't add or remove any functions.
 140   //
 141   // We also preserve all analyses on Functions, because we did all the
 142   // invalidation we needed to do above.
 143   PA.preserveSet<AllAnalysesOn<Function>>();
 144   PA.preserve<FunctionAnalysisManagerModuleProxy>();
 145   return PA;
 146 }
 147
 148 AnalysisSetKey CFGAnalyses::SetKey;
 149
 150 AnalysisSetKey PreservedAnalyses::AllAnalysesKey;