[llvm] [GVN] Teach GVN simple masked load/store forwarding (PR #157689)

[Matthew Devereau via llvm-commits]

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@@ -2734,6 +2779,11 @@ bool GVNPass::processInstruction(Instruction *I) {
     return false;
   }
 
+  if (auto *II = dyn_cast<IntrinsicInst>(I))
+    if (II && II->getIntrinsicID() == Intrinsic::masked_load)
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MDevereau wrote:

I'm not sure this is an improvement since m_Intrinsic cannot bind the intrinsic to a variable, and `I` would still need to be explicitly casted to an IntrinsicInst before passing it into processMaskedLoad.

https://github.com/llvm/llvm-project/pull/157689