[llvm] [SelectOpt] Add handling for Select-like operations. (PR #77284)

[David Sherwood via llvm-commits]

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@@ -368,15 +508,24 @@ void SelectOptimizeImpl::optimizeSelectsInnerLoops(Function &F,
 /// select instructions in \p Selects, look through the defining select
 /// instruction until the true/false value is not defined in \p Selects.
 static Value *
-getTrueOrFalseValue(SelectInst *SI, bool isTrue,
-                    const SmallPtrSet<const Instruction *, 2> &Selects) {
+getTrueOrFalseValue(SelectOptimizeImpl::SelectLike SI, bool isTrue,
+                    const SmallPtrSet<const Instruction *, 2> &Selects,
+                    IRBuilder<> &IB) {
   Value *V = nullptr;
-  for (SelectInst *DefSI = SI; DefSI != nullptr && Selects.count(DefSI);
+  for (SelectInst *DefSI = dyn_cast<SelectInst>(SI.getSI());
+       DefSI != nullptr && Selects.count(DefSI);
        DefSI = dyn_cast<SelectInst>(V)) {
-    assert(DefSI->getCondition() == SI->getCondition() &&
+    assert(DefSI->getCondition() == SI.getCondition() &&
            "The condition of DefSI does not match with SI");
     V = (isTrue ? DefSI->getTrueValue() : DefSI->getFalseValue());
   }
+
+  if (isa<BinaryOperator>(SI.getSI())) {
+    V = SI.getFalseValue();
+    if (isTrue)
+      V = IB.CreateOr(V, ConstantInt::get(V->getType(), 1));
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david-arm wrote:

Is this assuming there is currently on one type of BinaryOperator that is Select-like, i.e. an `or` instruction? If so, should that logic be hidden away in the SelectLike class?

https://github.com/llvm/llvm-project/pull/77284