[flang-commits] [flang] [flang] Characterize allocation based on MemAlloc effect instead of pattern matching (PR #166806)

[Valentin Clement バレンタイン クレメン via flang-commits]

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@@ -22,11 +22,73 @@
 #include "llvm/ADT/TypeSwitch.h"
 #include "llvm/Support/Casting.h"
 #include "llvm/Support/Debug.h"
+#include "mlir/Interfaces/ViewLikeInterface.h"
 
 using namespace mlir;
 
 #define DEBUG_TYPE "fir-alias-analysis"
 
+//===----------------------------------------------------------------------===//
+// AliasAnalysis: alias helpers
+//===----------------------------------------------------------------------===//
+
+static bool tryClassifyAllocateFromEffects(mlir::Operation *op,
+    mlir::Value candidate, bool allowValueScoped, bool allowOpScoped,
+    mlir::Value &v, mlir::Operation *&defOp,
+    fir::AliasAnalysis::SourceKind &type) {
+  auto iface = llvm::dyn_cast<mlir::MemoryEffectOpInterface>(op);
+  if (!iface)
+    return false;
+
+  llvm::SmallVector<mlir::MemoryEffects::EffectInstance, 4> effects;
+  iface.getEffects(effects);
+
+  if (allowValueScoped) {
+    for (mlir::MemoryEffects::EffectInstance &e : effects) {
+      if (mlir::isa<mlir::MemoryEffects::Allocate>(e.getEffect()) &&
+          e.getValue() && e.getValue() == candidate) {
+        v = candidate;
+        defOp = op;
+        type = fir::AliasAnalysis::SourceKind::Allocate;
+        return true;
+      }
+    }
+  }
+
+  if (!allowOpScoped)
+    return false;
+
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clementval wrote:

Yeah it's ok to modify the op. Just make it in a separate PR maybe. 

https://github.com/llvm/llvm-project/pull/166806