[llvm] [Attributor] Change allocation size and load/store offsets using AAPointerInfo for Alloca instructions (PR #72029)

[Johannes Doerfert via llvm-commits]

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@@ -12752,39 +12732,284 @@ struct AAAllocationInfoImpl : public AAAllocationInfo {
     assert(isValidState() &&
            "Manifest should only be called if the state is valid.");
 
-    Instruction *I = getIRPosition().getCtxI();
+    bool Changed = false;
+    const IRPosition &IRP = getIRPosition();
+    Instruction *I = IRP.getCtxI();
 
-    auto FixedAllocatedSizeInBits = getAllocatedSize()->getFixedValue();
+    // check if simplified values exist
+    if (checkIfSimplifiedValuesExists(A, I))
+      return ChangeStatus::UNCHANGED;
 
-    unsigned long NumBytesToAllocate = (FixedAllocatedSizeInBits + 7) / 8;
+    if (getAllocatedSize() == HasNoAllocationSize)
+      return ChangeStatus::UNCHANGED;
 
-    switch (I->getOpcode()) {
-    // TODO: add case for malloc like calls
-    case Instruction::Alloca: {
+    const AAPointerInfo *PI =
+        A.getOrCreateAAFor<AAPointerInfo>(IRP, *this, DepClassTy::REQUIRED);
 
-      AllocaInst *AI = cast<AllocaInst>(I);
+    if (!PI)
+      return ChangeStatus::UNCHANGED;
 
-      Type *CharType = Type::getInt8Ty(I->getContext());
+    if (!PI->getState().isValidState())
+      return ChangeStatus::UNCHANGED;
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jdoerfert wrote:

These can be assertions.

https://github.com/llvm/llvm-project/pull/72029