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

[Matthew Devereau via llvm-commits]

================
@@ -2287,6 +2288,46 @@ bool GVNPass::processLoad(LoadInst *L) {
   return true;
 }
 
+// Attempt to process masked loads which have loaded from
+// masked stores with the same mask
+bool GVNPass::processMaskedLoad(IntrinsicInst *I) {
+  Value *Mask = I->getOperand(2);
+  Value *Passthrough = I->getOperand(3);
+
+  MemDepResult Dep = MD->getDependency(I);
----------------
MDevereau wrote:

I've added the test `masked-load-store-no-mem-dep.ll` to deal with this.

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