[SandboxVec][BottomUpVec] Fix bug in invalidation of analyses

This makes sure we don't preserve analyses when we modify the IR.
This was causing errors in the EXPENSIVE_CHECKS build.

Author: vporpo

llvm/include/llvm/Transforms/Vectorize/SandboxVectorizer/Passes/BottomUpVec.h

@@ -30,7 +30,7 @@ class BottomUpVec final : public FunctionPass {
   /// \p Bndl. \p Operands are the already vectorized operands.
   Value *createVectorInstr(ArrayRef<Value *> Bndl, ArrayRef<Value *> Operands);
   Value *vectorizeRec(ArrayRef<Value *> Bndl);
-  void tryVectorize(ArrayRef<Value *> Seeds);
+  bool tryVectorize(ArrayRef<Value *> Seeds);
 
   // The PM containing the pipeline of region passes.
   RegionPassManager RPM;

llvm/lib/Transforms/Vectorize/SandboxVectorizer/Passes/BottomUpVec.cpp

@@ -54,6 +54,7 @@ getInsertPointAfterInstrs(ArrayRef<Value *> Instrs) {
 
 Value *BottomUpVec::createVectorInstr(ArrayRef<Value *> Bndl,
                                       ArrayRef<Value *> Operands) {
+  Change = true;
   assert(all_of(Bndl, [](auto *V) { return isa<Instruction>(V); }) &&
          "Expect Instructions!");
   auto &Ctx = Bndl[0]->getContext();
@@ -194,7 +195,10 @@ Value *BottomUpVec::vectorizeRec(ArrayRef<Value *> Bndl) {
   return NewVec;
 }
 
-void BottomUpVec::tryVectorize(ArrayRef<Value *> Bndl) { vectorizeRec(Bndl); }
+bool BottomUpVec::tryVectorize(ArrayRef<Value *> Bndl) {
+  vectorizeRec(Bndl);
+  return Change;
+}
 
 bool BottomUpVec::runOnFunction(Function &F, const Analyses &A) {
   Legality = std::make_unique<LegalityAnalysis>(
@@ -208,7 +212,7 @@ bool BottomUpVec::runOnFunction(Function &F, const Analyses &A) {
     // TODO: If vectorization succeeds, run the RegionPassManager on the
     // resulting region.
     if (Seeds.size() >= 2)
-      tryVectorize(Seeds);
+      Change |= tryVectorize(Seeds);
   }
   return Change;
 }