[llvm] [CanonicalizeFreezeInLoops] fix duplicate removal (PR #74716)

[Nikita Popov via llvm-commits]

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@@ -99,6 +87,46 @@ class CanonicalizeFreezeInLoopsImpl {
 
 } // anonymous namespace
 
+namespace llvm {
+
+struct FrozenIndPHIInfo {
+  // A freeze instruction that uses an induction phi
+  FreezeInst *FI = nullptr;
+  // The induction phi, step instruction, the operand idx of StepInst which is
+  // a step value
+  PHINode *PHI;
+  BinaryOperator *StepInst;
+  unsigned StepValIdx = 0;
+
+  FrozenIndPHIInfo(PHINode *PHI, BinaryOperator *StepInst)
+      : PHI(PHI), StepInst(StepInst) {}
+
+  bool operator==(const FrozenIndPHIInfo &Other) { return FI == Other.FI; }
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nikic wrote:

This function looks unused / unnecessary?

https://github.com/llvm/llvm-project/pull/74716