[flang-commits] [flang] [flang] Use alias analysis in lowering record assignments (PR #176483)

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@@ -1566,8 +1567,14 @@ void fir::factory::genRecordAssignment(fir::FirOpBuilder &builder,
       mlir::isa<fir::BaseBoxType>(fir::getBase(rhs).getType());
   auto recTy = mlir::dyn_cast<fir::RecordType>(baseTy);
   assert(recTy && "must be a record type");
+
+  // Use alias analysis to guard the fast path.
+  fir::AliasAnalysis aa;
+  bool disjoint = aa.alias(fir::getBase(lhs), fir::getBase(rhs)) ==
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MattPD wrote:

Thanks!

`disjoint = isTemporaryLHS || (aa.alias(fir::getBase(lhs), fir::getBase(rhs)) == mlir::AliasResult::NoAlias).` does make more sense--interestingly, I still get 2 new regressions in Lower/OpenACC/: acc-firstprivate-derived.f90 and acc-firstprivate-derived-user-assign.f90,  https://gist.github.com/MattPD/4a90d554fb8142b7126a8f9549a0c8eb

https://github.com/llvm/llvm-project/pull/176483