[flang-commits] [flang] [flang] AliasAnalysis: distinguish addr of arg vs. addr in arg (PR #87723)

[Slava Zakharin via flang-commits]

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@@ -399,19 +404,30 @@ AliasAnalysis::Source AliasAnalysis::getSource(mlir::Value v) {
   if (!defOp && type == SourceKind::Unknown)
     // Check if the memory source is coming through a dummy argument.
     if (isDummyArgument(v)) {
-      type = SourceKind::Argument;
       ty = v.getType();
       if (fir::valueHasFirAttribute(v, fir::getTargetAttrName()))
         attributes.set(Attribute::Target);
-
       if (Source::isPointerReference(ty))
         attributes.set(Attribute::Pointer);
+      if (followBoxAddr && fir::isa_ref_type(ty))
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vzakhari wrote:

I wonder if it will be more clear to only keep the first four source kinds and move `Direct` into the attributes.  We are looking for the source entity here, so the source kind should represent this source entity.  Whatever happens during the use-def chain walk should not affect the kind of the source entity that we end up finding.  The `Direct`, in this case, would mean that the reference value passed to `getSource` is a result of one or more dereferences of the original source.  I just find it easier to think about it this way, though, you may know cases where it can complicate the implementation.

https://github.com/llvm/llvm-project/pull/87723