[MLIR] Define getArgument() for Toy tutorial passes

This is important during debugging to be able to dump a pass pipeline.
It is also what is used by `--mlir-print-ir-tree-dir` to compute filenames
during dumps.

mlir/examples/toy/Ch4/mlir/ShapeInferencePass.cpp

@@ -55,6 +55,7 @@ namespace {
 struct ShapeInferencePass
     : public mlir::PassWrapper<ShapeInferencePass, OperationPass<toy::FuncOp>> {
   MLIR_DEFINE_EXPLICIT_INTERNAL_INLINE_TYPE_ID(ShapeInferencePass)
+  StringRef getArgument() const override { return "toy-shape-inference"; }
 
   void runOnOperation() override {
     auto f = getOperation();

mlir/examples/toy/Ch5/mlir/LowerToAffineLoops.cpp

@@ -328,6 +328,7 @@ namespace {
 struct ToyToAffineLoweringPass
     : public PassWrapper<ToyToAffineLoweringPass, OperationPass<ModuleOp>> {
   MLIR_DEFINE_EXPLICIT_INTERNAL_INLINE_TYPE_ID(ToyToAffineLoweringPass)
+  StringRef getArgument() const override { return "toy-to-affine"; }
 
   void getDependentDialects(DialectRegistry &registry) const override {
     registry.insert<affine::AffineDialect, func::FuncDialect,

mlir/examples/toy/Ch5/mlir/ShapeInferencePass.cpp

@@ -55,6 +55,7 @@ namespace {
 struct ShapeInferencePass
     : public mlir::PassWrapper<ShapeInferencePass, OperationPass<toy::FuncOp>> {
   MLIR_DEFINE_EXPLICIT_INTERNAL_INLINE_TYPE_ID(ShapeInferencePass)
+  StringRef getArgument() const override { return "toy-shape-inference"; }
 
   void runOnOperation() override {
     auto f = getOperation();

mlir/examples/toy/Ch6/mlir/LowerToAffineLoops.cpp

@@ -328,6 +328,7 @@ namespace {
 struct ToyToAffineLoweringPass
     : public PassWrapper<ToyToAffineLoweringPass, OperationPass<ModuleOp>> {
   MLIR_DEFINE_EXPLICIT_INTERNAL_INLINE_TYPE_ID(ToyToAffineLoweringPass)
+  StringRef getArgument() const override { return "toy-to-affine"; }
 
   void getDependentDialects(DialectRegistry &registry) const override {
     registry.insert<affine::AffineDialect, func::FuncDialect,

mlir/examples/toy/Ch6/mlir/LowerToLLVM.cpp

@@ -184,6 +184,7 @@ namespace {
 struct ToyToLLVMLoweringPass
     : public PassWrapper<ToyToLLVMLoweringPass, OperationPass<ModuleOp>> {
   MLIR_DEFINE_EXPLICIT_INTERNAL_INLINE_TYPE_ID(ToyToLLVMLoweringPass)
+  StringRef getArgument() const override { return "toy-to-llvm"; }
 
   void getDependentDialects(DialectRegistry &registry) const override {
     registry.insert<LLVM::LLVMDialect, scf::SCFDialect>();

mlir/examples/toy/Ch6/mlir/ShapeInferencePass.cpp

@@ -55,6 +55,7 @@ namespace {
 struct ShapeInferencePass
     : public mlir::PassWrapper<ShapeInferencePass, OperationPass<toy::FuncOp>> {
   MLIR_DEFINE_EXPLICIT_INTERNAL_INLINE_TYPE_ID(ShapeInferencePass)
+  StringRef getArgument() const override { return "toy-shape-inference"; }
 
   void runOnOperation() override {
     auto f = getOperation();

mlir/examples/toy/Ch7/mlir/LowerToAffineLoops.cpp

@@ -328,6 +328,7 @@ namespace {
 struct ToyToAffineLoweringPass
     : public PassWrapper<ToyToAffineLoweringPass, OperationPass<ModuleOp>> {
   MLIR_DEFINE_EXPLICIT_INTERNAL_INLINE_TYPE_ID(ToyToAffineLoweringPass)
+  StringRef getArgument() const override { return "toy-to-affine"; }
 
   void getDependentDialects(DialectRegistry &registry) const override {
     registry.insert<affine::AffineDialect, func::FuncDialect,

mlir/examples/toy/Ch7/mlir/LowerToLLVM.cpp

@@ -184,6 +184,7 @@ namespace {
 struct ToyToLLVMLoweringPass
     : public PassWrapper<ToyToLLVMLoweringPass, OperationPass<ModuleOp>> {
   MLIR_DEFINE_EXPLICIT_INTERNAL_INLINE_TYPE_ID(ToyToLLVMLoweringPass)
+  StringRef getArgument() const override { return "toy-to-llvm"; }
 
   void getDependentDialects(DialectRegistry &registry) const override {
     registry.insert<LLVM::LLVMDialect, scf::SCFDialect>();

mlir/examples/toy/Ch7/mlir/ShapeInferencePass.cpp

@@ -55,6 +55,7 @@ namespace {
 struct ShapeInferencePass
     : public mlir::PassWrapper<ShapeInferencePass, OperationPass<toy::FuncOp>> {
   MLIR_DEFINE_EXPLICIT_INTERNAL_INLINE_TYPE_ID(ShapeInferencePass)
+  StringRef getArgument() const override { return "toy-shape-inference"; }
 
   void runOnOperation() override {
     auto f = getOperation();