[llvm] [LLVM] Add `llvm.masked.compress` intrinsic (PR #92289)

[Luke Lau via llvm-commits]

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@@ -7197,6 +7199,48 @@ SDValue SelectionDAG::getNode(unsigned Opcode, const SDLoc &DL, EVT VT,
       return N1.getOperand(1);
     break;
   }
+  case ISD::MCOMPRESS: {
+    EVT VecVT = N1.getValueType();
+    EVT MaskVT = N2.getValueType();
+    (void)MaskVT;
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lukel97 wrote:

Oh sorry didn't realise that's what the rest of the file was using. We should probably mop up the other void uses now that we've migrated to C++17 (in another PR!)

https://github.com/llvm/llvm-project/pull/92289