[llvm] [SandboxVectorizer] Add container class to track and manage SeedBundles (PR #112048)

[Alina Sbirlea via llvm-commits]

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@@ -61,4 +65,68 @@ MutableArrayRef<Instruction *> SeedBundle::getSlice(unsigned StartIdx,
     return {};
 }
 
+template <typename LoadOrStoreT>
+SeedContainer::KeyT SeedContainer::getKey(LoadOrStoreT *LSI) const {
+  assert((isa<LoadInst>(LSI) || isa<StoreInst>(LSI)) &&
+         "Expected Load or Store!");
+  Value *Ptr = Utils::getMemInstructionBase(LSI);
+  Instruction::Opcode Op = LSI->getOpcode();
+  Type *Ty = Utils::getExpectedType(LSI);
+  if (auto *VTy = dyn_cast<VectorType>(Ty))
+    Ty = VTy->getElementType();
+  return {Ptr, Ty, Op};
+}
+
+// Explicit instantiations
+template SeedContainer::KeyT
+SeedContainer::getKey<LoadInst>(LoadInst *LSI) const;
+template SeedContainer::KeyT
+SeedContainer::getKey<StoreInst>(StoreInst *LSI) const;
+
+bool SeedContainer::erase(Instruction *I) {
+  assert((isa<LoadInst>(I) || isa<StoreInst>(I)) && "Expected Load or Store!");
+  auto It = SeedLookupMap.find(I);
+  if (It == SeedLookupMap.end())
+    return false;
+  SeedBundle *Bndl = It->second;
+  Bndl->setUsed(I);
+  return true;
+}
+
+template <typename LoadOrStoreT> void SeedContainer::insert(LoadOrStoreT *LSI) {
+  // Find the bundle containing seeds for this symbol and type-of-access.
+  auto &BundleVec = Bundles[getKey(LSI)];
+  // Fill this vector of bundles front to back so that only the last bundle in
+  // the vector may have available space. This avoids iteration to find one with
+  // space.
+  if (BundleVec.empty() || BundleVec.back()->size() == SeedBundleSizeLimit)
----------------
alinas wrote:

How will this work when instructions are inserted in out-of-order offsets? Can you move instructions between bundles to make space for one that "completes" another bundle, or do you avoid this by pre-sorting by offsets before insertion (I assumed this is not the case due to the logic in insert checking `Utils::atLowerAddress`) ?

https://github.com/llvm/llvm-project/pull/112048