[llvm] [DAGCombiner] Freeze maybe poison operands when folding select to logic (PR #84924)

[Björn Pettersson via llvm-commits]

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@@ -11307,28 +11307,34 @@ static SDValue foldBoolSelectToLogic(SDNode *N, SelectionDAG &DAG) {
   if (VT != Cond.getValueType() || VT.getScalarSizeInBits() != 1)
     return SDValue();
 
-  // select Cond, Cond, F --> or Cond, F
-  // select Cond, 1, F    --> or Cond, F
+  auto FreezeIfNeeded = [&](SDValue V) {
+    if (!DAG.isGuaranteedNotToBePoison(V))
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bjope wrote:

Ah. Nice!
Downstream I also needed some additional checks to just do this for my target (since it is a pain doing it for all targets until this has landed upstream). So that is one reason why I've wrapped the check this way.

https://github.com/llvm/llvm-project/pull/84924