[mlir][dataflow]Fix dense backward dataflow intraprocedural hook (#76865)

The dataflow analysis framework within MLIR allows to customize the
transfer function when a `call-like` operation is encuntered.

The check to see if the analysis was executed in intraprocedural mode
was executed after the check to see if the callee had the
CallableOpInterface, and thus intraprocedural analyses would behave as
interpocedural ones when performing indirect calls.

This commit fixes the issue by performing the check for
intraprocedurality first.

Dense forward analyses were already behaving correctly.
https://github.com/llvm/llvm-project/blob/main/mlir/lib/Analysis/DataFlow/DenseAnalysis.cpp#L63

Co-authored-by: massimo <[email protected]>

Author: drblallo

mlir/lib/Analysis/DataFlow/DenseAnalysis.cpp

@@ -283,17 +283,23 @@ void AbstractDenseBackwardDataFlowAnalysis::visitCallOperation(
     AbstractDenseLattice *before) {
   // Find the callee.
   Operation *callee = call.resolveCallable(&symbolTable);
-  auto callable = dyn_cast_or_null<CallableOpInterface>(callee);
-  if (!callable)
-    return setToExitState(before);
 
+  auto callable = dyn_cast_or_null<CallableOpInterface>(callee);
   // No region means the callee is only declared in this module.
-  Region *region = callable.getCallableRegion();
-  if (!region || region->empty() || !getSolverConfig().isInterprocedural()) {
+  // If that is the case or if the solver is not interprocedural,
+  // let the hook handle it.
+  if (!getSolverConfig().isInterprocedural() ||
+      (callable && (!callable.getCallableRegion() ||
+                    callable.getCallableRegion()->empty()))) {
     return visitCallControlFlowTransfer(
         call, CallControlFlowAction::ExternalCallee, after, before);
   }
 
+  if (!callable)
+    return setToExitState(before);
+
+  Region *region = callable.getCallableRegion();
+
   // Call-level control flow specifies the data flow here.
   //
   //   func.func @callee() {

mlir/test/Analysis/DataFlow/test-next-access.mlir

@@ -575,3 +575,21 @@ func.func @call_opaque_callee(%arg0: memref<f32>) {
   memref.load %arg0[] {name = "post"} : memref<f32>
   return
 }
+
+// -----
+
+// CHECK-LABEL: @indirect_call
+func.func @indirect_call(%arg0: memref<f32>, %arg1: (memref<f32>) -> ()) {
+  // IP:         name = "pre"
+  // IP-SAME:    next_access = ["unknown"]
+  // IP_AR:      name = "pre"
+  // IP_AR-SAME: next_access = ["unknown"] 
+  // LOCAL:      name = "pre"
+  // LOCAL-SAME: next_access = ["unknown"]
+  // LC_AR:      name = "pre"
+  // LC_AR-SAME: next_access = {{\[}}["call"]]
+  memref.load %arg0[] {name = "pre"} : memref<f32>
+  func.call_indirect %arg1(%arg0) {name = "call"} : (memref<f32>) -> ()
+  memref.load %arg0[] {name = "post"} : memref<f32>
+  return
+}