[mlir] Remove redundant control flow statements (NFC)

mlir/include/mlir/Analysis/DataFlow/DenseAnalysis.h

@@ -125,7 +125,7 @@ class AbstractDenseForwardDataFlowAnalysis : public DataFlowAnalysis {
   /// Visit an operation. If this analysis can confirm that lattice content
   /// of lattice anchors around operation are necessarily identical, join
   /// them into the same equivalent class.
-  virtual void buildOperationEquivalentLatticeAnchor(Operation *op) { return; }
+  virtual void buildOperationEquivalentLatticeAnchor(Operation *op) {}
 
   /// Propagate the dense lattice forward along the control flow edge from
   /// `regionFrom` to `regionTo` regions of the `branch` operation. `nullopt`
@@ -386,7 +386,7 @@ class AbstractDenseBackwardDataFlowAnalysis : public DataFlowAnalysis {
   /// Visit an operation. If this analysis can confirm that lattice content
   /// of lattice anchors around operation are necessarily identical, join
   /// them into the same equivalent class.
-  virtual void buildOperationEquivalentLatticeAnchor(Operation *op) { return; }
+  virtual void buildOperationEquivalentLatticeAnchor(Operation *op) {}
 
   /// Propagate the dense lattice backwards along the control flow edge from
   /// `regionFrom` to `regionTo` regions of the `branch` operation. `nullopt`

mlir/include/mlir/Analysis/DataFlowFramework.h

@@ -622,7 +622,7 @@ class DataFlowAnalysis {
   /// This function will union lattice anchor to same equivalent class if the
   /// analysis can determine the lattice content of lattice anchor is
   /// necessarily identical under the corrensponding lattice type.
-  virtual void initializeEquivalentLatticeAnchor(Operation *top) { return; }
+  virtual void initializeEquivalentLatticeAnchor(Operation *top) {}
 
 protected:
   /// Create a dependency between the given analysis state and lattice anchor

mlir/lib/Dialect/Mesh/IR/MeshOps.cpp

@@ -314,7 +314,6 @@ void mlir::mesh::maybeInsertTargetShardingAnnotation(MeshSharding sharding,
                                              newShardOp.getSharding(),
                                              /*annotate_for_users*/ true);
   rewriter.replaceAllUsesExcept(newShardOp, newShardOp2, newShardOp2);
-  return;
 }
 
 void mlir::mesh::maybeInsertTargetShardingAnnotation(MeshSharding sharding,

mlir/lib/Dialect/Tosa/Transforms/TosaValidation.cpp

@@ -463,7 +463,6 @@ struct TosaValidation : public tosa::impl::TosaValidationBase<TosaValidation> {
 
     depth++;
     getMaxNestedDepth(op, depth);
-    return;
   }
 
   bool levelCheckMaxNesting(Operation *op) {

mlir/test/lib/Dialect/Linalg/TestLinalgRankReduceContractionOps.cpp

@@ -51,7 +51,6 @@ struct TestLinalgRankReduceContractionOps
     linalg::populateContractionOpRankReducingPatterns(patterns);
     if (failed(applyPatternsGreedily(funcOp.getBody(), std::move(patterns))))
       return signalPassFailure();
-    return;
   }
 };