[Attributor] Remove notional overindexing check

[nikic]

Summary

AAPointerInfo currently bails on constant expression GEPs with notional overindexing. I don't think this is really relevant for this analysis and it should just check for constant indices instead. (Note that it would be fine to not check that either, as there are additional GEPOperator checks below that.)

After D117201, this is the last usage of isGEPWithNoNotionalOverIndexing() and I'd like to get rid of it.

[jdoerfert]

LG, see comment

llvm/lib/Transforms/IPO/AttributorAttributes.cpp

1185

dyn_cast? I agree we can drop the indices check. We need to verify it's a GEP though, at least given the code as it is.

[nikic]

llvm/lib/Transforms/IPO/AttributorAttributes.cpp

1185

Ooops, this was indeed supposed to be dyn_cast. Thanks for catching!

llvm/lib/Transforms/IPO/AttributorAttributes.cpp

auto UsePred = [&](const Use &U, bool &Follow) -> bool {
       assert(OffsetInfoMap.count(CurPtr) &&
              "The current pointer offset should have been seeded!");
 
       if (ConstantExpr *CE = dyn_cast<ConstantExpr>(Usr)) {
         if (CE->isCast())
           return HandlePassthroughUser(Usr, OffsetInfoMap[CurPtr], Follow);
         if (CE->isCompare())
           return true;
-        if (!CE->isGEPWithNoNotionalOverIndexing()) {
+        if (!isa<GEPOperator>(CE)) {
           LLVM_DEBUG(dbgs() << "[AAPointerInfo] Unhandled constant user " << *CE
                             << "\n");
           return false;
         }
       }
       if (auto *GEP = dyn_cast<GEPOperator>(Usr)) {
         // Note the order here, the Usr access might change the map, CurPtr is
         // already in it though.