[MemorySSA] Invalidate MemorySSA if AA or DT are invalidated.

[asbirlea]

Summary

MemorySSA keeps internal pointers of AA and DT.
If these get invalidated, so should MemorySSA.

[chandlerc]

LGTM

[chandlerc]

Oh, you can add a test for this by using the new PM and an invalidate<aa> pass or invalidate<domtree>.

[asbirlea]

Excellent suggestion! The invalidate needs to go into the Result internal to the analysis.
Updated and added test. PTAL.

[chandlerc]

LGTM

[RKSimon]

@asbirlea I'm sorry but I had to revert this at rL359555 as it was causing windows buildbot failures: http://lab.llvm.org:8011/builders/llvm-clang-lld-x86_64-scei-ps4-windows10pro-fast/builds/25459

[asbirlea]

Updated test MemorySSA/invalidate.ll: What follows "InvalidateAnalysisPass" looks different on Windows.

[asbirlea]

Rebase on ToT.

include/llvm/Analysis/MemorySSA.h

struct Result {
     Result(std::unique_ptr<MemorySSA> &&MSSA) : MSSA(std::move(MSSA)) {}
 
     MemorySSA &getMSSA() { return *MSSA.get(); }
 
     std::unique_ptr<MemorySSA> MSSA;
   };
 
   Result run(Function &F, FunctionAnalysisManager &AM);
+
+  bool invalidate(Function &F, const PreservedAnalyses &PA,
+                  FunctionAnalysisManager::Invalidator &Inv);
 };
 
 /// Printer pass for \c MemorySSA.
 class MemorySSAPrinterPass : public PassInfoMixin<MemorySSAPrinterPass> {
   raw_ostream &OS;
 
 public:
   explicit MemorySSAPrinterPass(raw_ostream &OS) : OS(OS) {}

lib/Analysis/MemorySSA.cpp

 
 MemorySSAAnalysis::Result MemorySSAAnalysis::run(Function &F,
                                                  FunctionAnalysisManager &AM) {
   auto &DT = AM.getResult<DominatorTreeAnalysis>(F);
   auto &AA = AM.getResult<AAManager>(F);
   return MemorySSAAnalysis::Result(llvm::make_unique<MemorySSA>(F, &AA, &DT));
 }
 
+bool MemorySSAAnalysis::invalidate(
+    Function &F, const PreservedAnalyses &PA,
+    FunctionAnalysisManager::Invalidator &Inv) {
+  auto PAC = PA.getChecker<MemorySSAAnalysis>();
+  return !(PAC.preserved() || PAC.preservedSet<AllAnalysesOn<Function>>()) ||
+         Inv.invalidate<AAManager>(F, PA) ||
+         Inv.invalidate<DominatorTreeAnalysis>(F, PA);
+}
+
 PreservedAnalyses MemorySSAPrinterPass::run(Function &F,
                                             FunctionAnalysisManager &AM) {
   OS << "MemorySSA for function: " << F.getName() << "\n";
   AM.getResult<MemorySSAAnalysis>(F).getMSSA().print(OS);
 
   return PreservedAnalyses::all();
 }