[llvm] [SimplifyIndVar] Push more users to worklist for simplifyUsers (PR #93598)

[via llvm-commits]

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@@ -942,11 +956,11 @@ void SimplifyIndvar::simplifyUsers(PHINode *CurrIV, IVVisitor *V) {
     if ((isa<PtrToIntInst>(UseInst)) || (isa<TruncInst>(UseInst)))
       for (Use &U : UseInst->uses()) {
         Instruction *User = cast<Instruction>(U.getUser());
-        if (replaceIVUserWithLoopInvariant(User))
+        if (DT->dominates(L->getHeader(), User->getParent()) &&
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v01dXYZ wrote:

We checked `UseInst` is dominated but not its users.

We need this condition to "protect" the following call `replaceIVUserWithLoopInvariant` to ensure we don't feed it with a phi that is already invariant. It was not necessary before because the loop is LCSSA and any exits would be fenced with phis.

I could have misunderstood your point though.

https://github.com/llvm/llvm-project/pull/93598