5 files changed, 132 insertions, 5 deletions

diff --git a/llvm/lib/Analysis/CGSCCPassManager.cpp b/llvm/lib/Analysis/CGSCCPassManager.cpp
index c72b0efce81..b2bee0258d1 100644
--- a/llvm/lib/Analysis/CGSCCPassManager.cpp
+++ b/llvm/lib/Analysis/CGSCCPassManager.cpp
@@ -13,6 +13,8 @@
 
 using namespace llvm;
 
+// Explicit template instantiations and specialization defininitions for core
+// template typedefs.
 namespace llvm {
 
 // Explicit instantiations for the core proxy templates.
@@ -22,9 +24,9 @@ template class PassManager<LazyCallGraph::SCC, CGSCCAnalysisManager,
                            LazyCallGraph &, CGSCCUpdateResult &>;
 template class InnerAnalysisManagerProxy<CGSCCAnalysisManager, Module>;
 template class OuterAnalysisManagerProxy<ModuleAnalysisManager,
-                                         LazyCallGraph::SCC>;
+                                         LazyCallGraph::SCC, LazyCallGraph &>;
 template class InnerAnalysisManagerProxy<FunctionAnalysisManager,
-                                         LazyCallGraph::SCC>;
+                                         LazyCallGraph::SCC, LazyCallGraph &>;
 template class OuterAnalysisManagerProxy<CGSCCAnalysisManager, Function>;
 
 /// Explicitly specialize the pass manager run method to handle call graph
@@ -84,6 +86,87 @@ PassManager<LazyCallGraph::SCC, CGSCCAnalysisManager, LazyCallGraph &,
   return PA;
 }
 
+bool CGSCCAnalysisManagerModuleProxy::Result::invalidate(
+    Module &M, const PreservedAnalyses &PA,
+    ModuleAnalysisManager::Invalidator &Inv) {
+  // If this proxy or the call graph is going to be invalidated, we also need
+  // to clear all the keys coming from that analysis.
+  //
+  // We also directly invalidate the FAM's module proxy if necessary, and if
+  // that proxy isn't preserved we can't preserve this proxy either. We rely on
+  // it to handle module -> function analysis invalidation in the face of
+  // structural changes and so if it's unavailable we conservatively clear the
+  // entire SCC layer as well rather than trying to do invaliadtion ourselves.
+  if (!PA.preserved<CGSCCAnalysisManagerModuleProxy>() ||
+      Inv.invalidate<LazyCallGraphAnalysis>(M, PA) ||
+      Inv.invalidate<FunctionAnalysisManagerModuleProxy>(M, PA)) {
+    InnerAM->clear();
+
+    // And the proxy itself should be marked as invalid so that we can observe
+    // the new call graph. This isn't strictly necessary because we cheat
+    // above, but is still useful.
+    return true;
+  }
+
+  // Ok, we have a graph, so we can propagate the invalidation down into it.
+  for (auto &RC : G->postorder_ref_sccs())
+    for (auto &C : RC)
+      InnerAM->invalidate(C, PA);
+
+  // Return false to indicate that this result is still a valid proxy.
+  return false;
+}
+
+template <>
+CGSCCAnalysisManagerModuleProxy::Result
+CGSCCAnalysisManagerModuleProxy::run(Module &M, ModuleAnalysisManager &AM) {
+  // Force the Function analysis manager to also be available so that it can
+  // be accessed in an SCC analysis and proxied onward to function passes.
+  // FIXME: It is pretty awkward to just drop the result here and assert that
+  // we can find it again later.
+  (void)AM.getResult<FunctionAnalysisManagerModuleProxy>(M);
+
+  return Result(*InnerAM, AM.getResult<LazyCallGraphAnalysis>(M));
+}
+
+AnalysisKey FunctionAnalysisManagerCGSCCProxy::Key;
+
+FunctionAnalysisManagerCGSCCProxy::Result
+FunctionAnalysisManagerCGSCCProxy::run(LazyCallGraph::SCC &C,
+                                       CGSCCAnalysisManager &AM,
+                                       LazyCallGraph &CG) {
+  // Collect the FunctionAnalysisManager from the Module layer and use that to
+  // build the proxy result.
+  //
+  // This allows us to rely on the FunctionAnalysisMangaerModuleProxy to
+  // invalidate the function analyses.
+  auto &MAM = AM.getResult<ModuleAnalysisManagerCGSCCProxy>(C, CG).getManager();
+  Module &M = *C.begin()->getFunction().getParent();
+  auto *FAMProxy = MAM.getCachedResult<FunctionAnalysisManagerModuleProxy>(M);
+  assert(FAMProxy && "The CGSCC pass manager requires that the FAM module "
+                     "proxy is run on the module prior to entering the CGSCC "
+                     "walk.");
+
+  // Note that we special-case invalidation handling of this proxy in the CGSCC
+  // analysis manager's Module proxy. This avoids the need to do anything
+  // special here to recompute all of this if ever the FAM's module proxy goes
+  // away.
+  return Result(FAMProxy->getManager());
+}
+
+bool FunctionAnalysisManagerCGSCCProxy::Result::invalidate(
+    LazyCallGraph::SCC &C, const PreservedAnalyses &PA,
+    CGSCCAnalysisManager::Invalidator &Inv) {
+  for (LazyCallGraph::Node &N : C)
+    FAM->invalidate(N.getFunction(), PA);
+
+  // This proxy doesn't need to handle invalidation itself. Instead, the
+  // module-level CGSCC proxy handles it above by ensuring that if the
+  // module-level FAM proxy becomes invalid the entire SCC layer, which
+  // includes this proxy, is cleared.
+  return false;
+}
+
 } // End llvm namespace
 
 namespace {
diff --git a/llvm/lib/Analysis/LoopPassManager.cpp b/llvm/lib/Analysis/LoopPassManager.cpp
index 8bac19a5821..5b40a0beff7 100644
--- a/llvm/lib/Analysis/LoopPassManager.cpp
+++ b/llvm/lib/Analysis/LoopPassManager.cpp
@@ -17,12 +17,30 @@
 
 using namespace llvm;
 
-// Explicit instantiations for core typedef'ed templates.
+// Explicit template instantiations and specialization defininitions for core
+// template typedefs.
 namespace llvm {
 template class PassManager<Loop>;
 template class AnalysisManager<Loop>;
 template class InnerAnalysisManagerProxy<LoopAnalysisManager, Function>;
 template class OuterAnalysisManagerProxy<FunctionAnalysisManager, Loop>;
+
+template <>
+bool LoopAnalysisManagerFunctionProxy::Result::invalidate(
+    Function &F, const PreservedAnalyses &PA,
+    FunctionAnalysisManager::Invalidator &Inv) {
+  // If this proxy isn't marked as preserved, the set of Function objects in
+  // the module may have changed. We therefore can't call
+  // InnerAM->invalidate(), because any pointers to Functions it has may be
+  // stale.
+  if (!PA.preserved(LoopAnalysisManagerFunctionProxy::ID()))
+    InnerAM->clear();
+
+  // FIXME: Proper suppor for invalidation isn't yet implemented for the LPM.
+
+  // Return false to indicate that this result is still a valid proxy.
+  return false;
+}
 }
 
 PreservedAnalyses llvm::getLoopPassPreservedAnalyses() {
diff --git a/llvm/lib/IR/PassManager.cpp b/llvm/lib/IR/PassManager.cpp
index 171805f7d24..7c478ea1cf6 100644
--- a/llvm/lib/IR/PassManager.cpp
+++ b/llvm/lib/IR/PassManager.cpp
@@ -13,7 +13,8 @@
 
 using namespace llvm;
 
-// Explicit template instantiations for core template typedefs.
+// Explicit template instantiations and specialization defininitions for core
+// template typedefs.
 namespace llvm {
 template class AllAnalysesOn<Module>;
 template class AllAnalysesOn<Function>;
@@ -23,6 +24,31 @@ 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 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.
+  if (!PA.preserved(FunctionAnalysisManagerModuleProxy::ID())) {
+    InnerAM->clear();
+    return true;
+  }
+
+  // Otherwise propagate the invalidation event to all the remaining IR units.
+  for (Function &F : M)
+    InnerAM->invalidate(F, PA);
+
+  // Return false to indicate that this result is still a valid proxy.
+  return false;
+}
 }
 
 AnalysisKey PreservedAnalyses::AllAnalysesKey;
diff --git a/llvm/lib/Passes/PassBuilder.cpp b/llvm/lib/Passes/PassBuilder.cpp
index 98694fd9788..ce523ae5793 100644
--- a/llvm/lib/Passes/PassBuilder.cpp
+++ b/llvm/lib/Passes/PassBuilder.cpp
@@ -769,7 +769,6 @@ void PassBuilder::crossRegisterProxies(LoopAnalysisManager &LAM,
                                        ModuleAnalysisManager &MAM) {
   MAM.registerPass([&] { return FunctionAnalysisManagerModuleProxy(FAM); });
   MAM.registerPass([&] { return CGSCCAnalysisManagerModuleProxy(CGAM); });
-  CGAM.registerPass([&] { return FunctionAnalysisManagerCGSCCProxy(FAM); });
   CGAM.registerPass([&] { return ModuleAnalysisManagerCGSCCProxy(MAM); });
   FAM.registerPass([&] { return CGSCCAnalysisManagerFunctionProxy(CGAM); });
   FAM.registerPass([&] { return ModuleAnalysisManagerFunctionProxy(MAM); });
diff --git a/llvm/lib/Passes/PassRegistry.def b/llvm/lib/Passes/PassRegistry.def
index d3a6be871ad..a35e7e8caf1 100644
--- a/llvm/lib/Passes/PassRegistry.def
+++ b/llvm/lib/Passes/PassRegistry.def
@@ -79,6 +79,7 @@ MODULE_PASS("verify", VerifierPass())
 #define CGSCC_ANALYSIS(NAME, CREATE_PASS)
 #endif
 CGSCC_ANALYSIS("no-op-cgscc", NoOpCGSCCAnalysis())
+CGSCC_ANALYSIS("fam-proxy", FunctionAnalysisManagerCGSCCProxy())
 #undef CGSCC_ANALYSIS
 
 #ifndef CGSCC_PASS