3 files changed, 11 insertions, 30 deletions

diff --git a/llvm/lib/Transforms/IPO/FunctionAttrs.cpp b/llvm/lib/Transforms/IPO/FunctionAttrs.cpp
index 402a66552c2..740e9fb8b90 100644
--- a/llvm/lib/Transforms/IPO/FunctionAttrs.cpp
+++ b/llvm/lib/Transforms/IPO/FunctionAttrs.cpp
@@ -1275,16 +1275,9 @@ PreservedAnalyses
 ReversePostOrderFunctionAttrsPass::run(Module &M, ModuleAnalysisManager &AM) {
   auto &CG = AM.getResult<CallGraphAnalysis>(M);
 
-  bool Changed = deduceFunctionAttributeInRPO(M, CG);
-
-  // CallGraphAnalysis holds AssertingVH and must be invalidated eagerly so
-  // that other passes don't delete stuff from under it.
-  // FIXME: We need to invalidate this to avoid PR28400. Is there a better
-  // solution?
-  AM.invalidate<CallGraphAnalysis>(M);
-
-  if (!Changed)
+  if (!deduceFunctionAttributeInRPO(M, CG))
     return PreservedAnalyses::all();
+
   PreservedAnalyses PA;
   PA.preserve<CallGraphAnalysis>();
   return PA;
diff --git a/llvm/lib/Transforms/IPO/GlobalDCE.cpp b/llvm/lib/Transforms/IPO/GlobalDCE.cpp
index 9304e783d49..67e9d20eb92 100644
--- a/llvm/lib/Transforms/IPO/GlobalDCE.cpp
+++ b/llvm/lib/Transforms/IPO/GlobalDCE.cpp
@@ -144,29 +144,13 @@ PreservedAnalyses GlobalDCEPass::run(Module &M, ModuleAnalysisManager &MAM) {
       }
     }
 
-  // Because we may have cached analyses for functions we take extra care when
-  // deleting them if there is an active proxy. If there isn't, then we get to
-  // assume that everything in the function AM has been cleared already.
-  // FIXME: Note that all of this will happen automatically when this pass
-  // finishes. Unfortuantely there are analyses which hold asserting VHs to
-  // IR units. We could make those weak VHs that would assert if ever used
-  // without asserting eagerly and then all of this knowledge of the analysis
-  // manager could go away.
-  FunctionAnalysisManager *FAM = nullptr;
-  if (auto *FAMProxy =
-          MAM.getCachedResult<FunctionAnalysisManagerModuleProxy>(M))
-    FAM = &FAMProxy->getManager();
-
   // The second pass drops the bodies of functions which are dead...
   std::vector<Function *> DeadFunctions;
   for (Function &F : M)
     if (!AliveGlobals.count(&F)) {
       DeadFunctions.push_back(&F);         // Keep track of dead globals
-      if (!F.isDeclaration()) {
-        if (FAM)
-          FAM->clear(F);
+      if (!F.isDeclaration())
         F.deleteBody();
-      }
     }
 
   // The third pass drops targets of aliases which are dead...
diff --git a/llvm/lib/Transforms/IPO/Inliner.cpp b/llvm/lib/Transforms/IPO/Inliner.cpp
index e2dc1158549..767a2076de6 100644
--- a/llvm/lib/Transforms/IPO/Inliner.cpp
+++ b/llvm/lib/Transforms/IPO/Inliner.cpp
@@ -887,11 +887,10 @@ PreservedAnalyses InlinerPass::run(LazyCallGraph::SCC &InitialC,
         // made dead by this operation on other functions).
         Callee.removeDeadConstantUsers();
         if (Callee.use_empty()) {
-          // Clear all analyses and the body and queue the function itself for
-          // deletion when we finish inlining and call graph updates.
+          // Clear the body and queue the function itself for deletion when we
+          // finish inlining and call graph updates.
           // Note that after this point, it is an error to do anything other
           // than use the callee's address or delete it.
-          FAM.clear(Callee);
           Callee.dropAllReferences();
           assert(find(DeadFunctions, &Callee) == DeadFunctions.end() &&
                  "Cannot put cause a function to become dead twice!");
@@ -939,8 +938,13 @@ PreservedAnalyses InlinerPass::run(LazyCallGraph::SCC &InitialC,
   // sets.
   for (Function *DeadF : DeadFunctions) {
     // Get the necessary information out of the call graph and nuke the
-    // function there.
+    // function there. Also, cclear out any cached analyses.
     auto &DeadC = *CG.lookupSCC(*CG.lookup(*DeadF));
+    FunctionAnalysisManager &FAM =
+        AM.getResult<FunctionAnalysisManagerCGSCCProxy>(DeadC, CG)
+            .getManager();
+    FAM.clear(*DeadF);
+    AM.clear(DeadC);
     auto &DeadRC = DeadC.getOuterRefSCC();
     CG.removeDeadFunction(*DeadF);