1 files changed, 95 insertions, 0 deletions
diff --git a/llvm/lib/IR/PassManager.cpp b/llvm/lib/IR/PassManager.cpp
new file mode 100644
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+++ b/llvm/lib/IR/PassManager.cpp
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+//===- PassManager.cpp - Infrastructure for managing & running IR passes --===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/IR/PassManager.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/IR/LLVMContext.h"
+
+using namespace llvm;
+
+// Explicit template instantiations and specialization defininitions for core
+// template typedefs.
+namespace llvm {
+template class AllAnalysesOn<Module>;
+template class AllAnalysesOn<Function>;
+template class PassManager<Module>;
+template class PassManager<Function>;
+template class AnalysisManager<Module>;
+template class AnalysisManager<Function>;
+template class InnerAnalysisManagerProxy<FunctionAnalysisManager, Module>;
+template class OuterAnalysisManagerProxy<ModuleAnalysisManager, Function>;
+
+template <>
+bool FunctionAnalysisManagerModuleProxy::Result::invalidate(
+    Module &M, const PreservedAnalyses &PA,
+    ModuleAnalysisManager::Invalidator &Inv) {
+  // If literally everything is preserved, we're done.
+  if (PA.areAllPreserved())
+    return false; // This is still a valid proxy.
+
+  // If this proxy isn't marked as preserved, then even if the result remains
+  // valid, the key itself may no longer be valid, so we clear everything.
+  //
+  // Note that in order to preserve this proxy, a module pass must ensure that
+  // the FAM has been completely updated to handle the deletion of functions.
+  // Specifically, any FAM-cached results for those functions need to have been
+  // forcibly cleared. When preserved, this proxy will only invalidate results
+  // cached on functions *still in the module* at the end of the module pass.
+  auto PAC = PA.getChecker<FunctionAnalysisManagerModuleProxy>();
+  if (!PAC.preserved() && !PAC.preservedSet<AllAnalysesOn<Module>>()) {
+    InnerAM->clear();
+    return true;
+  }
+
+  // Directly check if the relevant set is preserved.
+  bool AreFunctionAnalysesPreserved =
+      PA.allAnalysesInSetPreserved<AllAnalysesOn<Function>>();
+
+  // Now walk all the functions to see if any inner analysis invalidation is
+  // necessary.
+  for (Function &F : M) {
+    Optional<PreservedAnalyses> FunctionPA;
+
+    // Check to see whether the preserved set needs to be pruned based on
+    // module-level analysis invalidation that triggers deferred invalidation
+    // registered with the outer analysis manager proxy for this function.
+    if (auto *OuterProxy =
+            InnerAM->getCachedResult<ModuleAnalysisManagerFunctionProxy>(F))
+      for (const auto &OuterInvalidationPair :
+           OuterProxy->getOuterInvalidations()) {
+        AnalysisKey *OuterAnalysisID = OuterInvalidationPair.first;
+        const auto &InnerAnalysisIDs = OuterInvalidationPair.second;
+        if (Inv.invalidate(OuterAnalysisID, M, PA)) {
+          if (!FunctionPA)
+            FunctionPA = PA;
+          for (AnalysisKey *InnerAnalysisID : InnerAnalysisIDs)
+            FunctionPA->abandon(InnerAnalysisID);
+        }
+      }
+
+    // Check if we needed a custom PA set, and if so we'll need to run the
+    // inner invalidation.
+    if (FunctionPA) {
+      InnerAM->invalidate(F, *FunctionPA);
+      continue;
+    }
+
+    // Otherwise we only need to do invalidation if the original PA set didn't
+    // preserve all function analyses.
+    if (!AreFunctionAnalysesPreserved)
+      InnerAM->invalidate(F, PA);
+  }
+
+  // Return false to indicate that this result is still a valid proxy.
+  return false;
+}
+}
+
+AnalysisSetKey CFGAnalyses::SetKey;
+
+AnalysisSetKey PreservedAnalyses::AllAnalysesKey;