Fix use_iterator in ARM64AddressTypePromotion

[weimingz]

Summary

change use_iterator to user_iterator

[weimingz]

Ping?

Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation

[weimingz]

const Instruction *Inst = dyn_cast<GetElementPtrInst>(U) looks wrong. The rest two might be OK. Can someone take a quick look? Thanks

[t.p.northover]

Hi Weiming,

Did you try to come up with a test for these? You could well be right, but it's a bit difficult to say with bare code like this.

Cheers.

Tim.

[weimingz]

Hi Tim,

Unfortunately I have no test case yet. I spot that when I scan the code for use_iterator. We got some issues with change of Use class. The tricky thing is, sometime it just causes the optimization exit quietly, no build fail or runtime assertion.

Anyway, I'll keep an eye on it and let you know if I find out something.

Thanks,
Weiming

Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation

lib/Target/ARM64/ARM64AddressTypePromotion.cpp

     return false;
 
   for (const Use &U : SExt->uses()) {
-    if (isa<GetElementPtrInst>(*U))
+    if (isa<GetElementPtrInst>(U.getUser()))
       return true;
   }
 

         // been moved yet.
         while (!Inst->use_empty()) {
           Value::use_iterator UseIt = Inst->use_begin();
-          Instruction *UseInst = dyn_cast<Instruction>(*UseIt);
+          Instruction *UseInst = dyn_cast<Instruction>(UseIt->getUser());
           assert(UseInst && "Use of sext is not an Instruction!");
           UseInst->setOperand(UseIt->getOperandNo(), SExt);
         }

       bool insert = false;
       // #1.
       for (const Use &U : SExt->uses()) {
-        const Instruction *Inst = dyn_cast<GetElementPtrInst>(U);
+        const Instruction *Inst = dyn_cast<GetElementPtrInst>(U.getUser());
         if (Inst && Inst->getNumOperands() > 2) {
           DEBUG(dbgs() << "Interesting use in GetElementPtrInst\n" << *Inst
                        << '\n');