[flang-commits] [flang] [flang] AliasAnalysis: More formally define and distinguish between data and non-data (PR #91020)

[Joel E. Denny via flang-commits]

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@@ -88,70 +108,35 @@ AliasResult AliasAnalysis::alias(Value lhs, Value rhs) {
   auto lhsSrc = getSource(lhs);
   auto rhsSrc = getSource(rhs);
   bool approximateSource = lhsSrc.approximateSource || rhsSrc.approximateSource;
-  LLVM_DEBUG(llvm::dbgs() << "AliasAnalysis::alias\n";
+  LLVM_DEBUG(llvm::dbgs() << "\n"; llvm::dbgs() << "AliasAnalysis::alias\n";
              llvm::dbgs() << "  lhs: " << lhs << "\n";
              llvm::dbgs() << "  lhsSrc: " << lhsSrc << "\n";
              llvm::dbgs() << "  rhs: " << rhs << "\n";
-             llvm::dbgs() << "  rhsSrc: " << rhsSrc << "\n";
-             llvm::dbgs() << "\n";);
+             llvm::dbgs() << "  rhsSrc: " << rhsSrc << "\n";);
 
   // Indirect case currently not handled. Conservatively assume
   // it aliases with everything
-  if (lhsSrc.kind > SourceKind::Direct || rhsSrc.kind > SourceKind::Direct) {
+  if (lhsSrc.kind >= SourceKind::Indirect ||
+      rhsSrc.kind >= SourceKind::Indirect) {
     return AliasResult::MayAlias;
   }
 
-  // SourceKind::Direct is set for the addresses wrapped in a global boxes.
-  // ie: fir.global @_QMpointersEp : !fir.box<!fir.ptr<f32>>
-  // Though nothing is known about them, they would only alias with targets or
-  // pointers
-  bool directSourceToNonTargetOrPointer = false;
-  if (lhsSrc.u != rhsSrc.u || lhsSrc.kind != rhsSrc.kind) {
-    if ((lhsSrc.kind == SourceKind::Direct && !rhsSrc.isTargetOrPointer()) ||
-        (rhsSrc.kind == SourceKind::Direct && !lhsSrc.isTargetOrPointer()))
-      directSourceToNonTargetOrPointer = true;
-  }
-
-  if (lhsSrc.kind == SourceKind::Direct ||
-      rhsSrc.kind == SourceKind::Direct) {
-    if (!directSourceToNonTargetOrPointer)
-      return AliasResult::MayAlias;
-  }
-
   if (lhsSrc.kind == rhsSrc.kind) {
-    if (lhsSrc.u == rhsSrc.u) {
+    if (lhsSrc.origin == rhsSrc.origin) {
+      LLVM_DEBUG(llvm::dbgs()
+                 << "  aliasing because same source kind and origin\n");
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jdenny-ornl wrote:

Thanks for adding this debug output!

https://github.com/llvm/llvm-project/pull/91020