[llvm] [Attributor] Propagate alignment through ptrmask (PR #150158)

[via llvm-commits]

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@@ -5501,6 +5550,15 @@ struct AAAlignCallSiteReturned final
   AAAlignCallSiteReturned(const IRPosition &IRP, Attributor &A)
       : Base(IRP, A) {}
 
+  ChangeStatus updateImpl(Attributor &A) override {
+    Instruction *I = getIRPosition().getCtxI();
+    if (const IntrinsicInst *II = dyn_cast<IntrinsicInst>(I)) {
+      Align Align = getAssumedAlignForIntrinsic(A, *this, *II);
+      return clampStateAndIndicateChange<StateType>(this->getState(),
+                                                    Align.value());
+    }
+    return Base::updateImpl(A);
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Shoreshen wrote:

Hi @shiltian , same as known I cannot tell from the return value that if it is correctly handled.

But what is different here is if it is intrinsic, the call will be equivalently handled as call to deceleration, which will create a pessimistic alignment attribute for the caller. so the following handle can be ignored and directly return here.

https://github.com/llvm/llvm-project/pull/150158