[TIR][REFACTIR] Update TIR nodes std::string->String. (#5793)

This PR updates the remaining TIR node's member to use
String instead of std::string.

include/tvm/ir/adt.h

@@ -45,7 +45,7 @@ namespace tvm {
 class ConstructorNode : public RelayExprNode {
  public:
   /*! \brief The name (only a hint) */
-  std::string name_hint;
+  String name_hint;
   /*! \brief Input to the constructor. */
   Array<Type> inputs;
   /*! \brief The datatype the constructor will construct. */

include/tvm/ir/attrs.h

@@ -27,7 +27,7 @@
  *   struct MyAttrs : public tvm::AttrsNode<MyAttrs> {
  *     float learning_rate;
  *     int num_hidden;
- *     std::string name;
+ *     String name;
  *     // declare attribute fields in header file
  *     TVM_DECLARE_ATTRS(MyAttrs, "attrs.MyAttrs") {
  *       TVM_ATTR_FIELD(num_hidden).set_lower_bound(1);
@@ -106,11 +106,11 @@ struct AttrError : public dmlc::Error {
 class AttrFieldInfoNode : public Object {
  public:
   /*! \brief name of the field */
-  std::string name;
+  String name;
   /*! \brief type docstring information in str. */
-  std::string type_info;
+  String type_info;
   /*! \brief detailed description of the type */
-  std::string description;
+  String description;
 
   void VisitAttrs(AttrVisitor* v) {
     v->Visit("name", &name);

include/tvm/ir/env_func.h

@@ -41,7 +41,7 @@ namespace tvm {
 class EnvFuncNode : public Object {
  public:
   /*! \brief Unique name of the global function */
-  std::string name;
+  String name;
   /*! \brief The internal packed function */
   runtime::PackedFunc func;
   /*! \brief constructor */

include/tvm/ir/op.h

@@ -58,21 +58,21 @@ class OpAttrMap;
 class OpNode : public RelayExprNode {
  public:
   /*! \brief name of the operator */
-  std::string name;
+  String name;
   /*! \brief the type of the operator */
   mutable FuncType op_type;
   /*!
    * \brief detailed description of the operator
    *  This can be used to generate docstring automatically for the operator.
    */
-  std::string description;
+  String description;
   /* \brief Information of input arguments to the operator */
   Array<AttrFieldInfo> arguments;
   /*!
    * \brief The type key of the attribute field
    *  This can be empty, in which case it defaults to anything.
    */
-  std::string attrs_type_key;
+  String attrs_type_key;
   /*!
    * \brief attribute type index,
    * this field varies in each run and is not exposed to frontend.

include/tvm/ir/transform.h

@@ -253,10 +253,10 @@ class PassInfoNode : public Object {
   int opt_level;
 
   /*! \brief The name of an optimization/analysis pass. */
-  std::string name;
+  String name;
 
   /*! \brief The passes that are required to perform the current pass. */
-  Array<runtime::String> required;
+  Array<String> required;
 
   PassInfoNode() = default;
 
@@ -407,7 +407,7 @@ class Sequential : public Pass {
  */
 TVM_DLL Pass
 CreateModulePass(const runtime::TypedPackedFunc<IRModule(IRModule, PassContext)>& pass_func,
-                 int opt_level, const String& name, const Array<runtime::String>& required);
+                 int opt_level, String name, Array<runtime::String> required);
 
 /*!
  * \brief A special trace pass that prints the header and IR to LOG(INFO).

include/tvm/node/reflection.h

@@ -169,7 +169,7 @@ class ReflectionVTable {
    * \return The corresponding attribute value.
    * \note This function will throw an exception if the object does not contain the field.
    */
-  TVM_DLL runtime::TVMRetValue GetAttr(Object* self, const std::string& attr_name) const;
+  TVM_DLL runtime::TVMRetValue GetAttr(Object* self, const String& attr_name) const;
 
   /*!
    * \brief List all the fields in the object.

include/tvm/relay/op_strategy.h

@@ -46,7 +46,7 @@ class OpImplementationNode : public Object {
   /*! \brief Schedule function */
   FTVMSchedule fschedule;
   /*! \brief Name of the implementation */
-  std::string name;
+  String name;
   /*! \brief Priority level */
   int plevel;
 

include/tvm/relay/transform.h

@@ -58,7 +58,7 @@ using Sequential = tvm::transform::Sequential;
  */
 TVM_DLL Pass CreateFunctionPass(
     const runtime::TypedPackedFunc<Function(Function, IRModule, PassContext)>& pass_func,
-    int opt_level, const String& name, const tvm::Array<runtime::String>& required);
+    int opt_level, String name, tvm::Array<String> required);
 
 /*! \brief Remove expressions which does not effect the program result.
  *

include/tvm/runtime/container.h

@@ -65,6 +65,11 @@
 #include <utility>
 #include <vector>
 
+namespace llvm {
+// String to llvm object compatibility.
+class StringRef;
+}  // namespace llvm
+
 namespace tvm {
 
 struct ObjectEqual;
@@ -1161,7 +1166,14 @@ class String : public ObjectRef {
    * \param other The value for the new String
    *
    */
-  inline String operator=(std::string other);
+  inline String& operator=(std::string other);
+
+  /*!
+   * \brief Change the value the reference object points to.
+   *
+   * \param other The value for the new String
+   */
+  inline String& operator=(const char* other);
 
   /*!
    * \brief Compare is less than other std::string
@@ -1304,12 +1316,20 @@ class String : public ObjectRef {
   const char* data() const { return get()->data; }
 
   /*!
-   * \brief Convert String to an std::sting object
+   * \brief Convert String to an std::string object
    *
    * \return std::string
    */
   operator std::string() const { return std::string{get()->data, size()}; }
 
+  // LLVM compatibility function, implemented in src/target/llvm/llvm_common.h
+  /*!
+   * \brief Convert String to an llvm::StringRef object
+   *
+   * \return llvm::StringRef
+   */
+  inline operator llvm::StringRef() const;
+
   /*!
    * \brief Check if a TVMArgValue can be converted to String, i.e. it can be std::string or String
    * \param val The value to be checked
@@ -1382,12 +1402,14 @@ inline String::String(std::string other) {
   data_ = std::move(ptr);
 }
 
-inline String String::operator=(std::string other) {
+inline String& String::operator=(std::string other) {
   String replace{std::move(other)};
   data_.swap(replace.data_);
-  return Downcast<String>(*this);
+  return *this;
 }
 
+inline String& String::operator=(const char* other) { return operator=(std::string(other)); }
+
 inline String operator+(const std::string lhs, const String& rhs) {
   return lhs + rhs.operator std::string();
 }

include/tvm/tir/buffer.h

@@ -65,9 +65,9 @@ class BufferNode : public Object {
   PrimExpr elem_offset;
   // Meta data
   /*! \brief optional name of the buffer */
-  std::string name;
+  String name;
   /*! \brief storage scope of the buffer, if other than global */
-  std::string scope;
+  String scope;
   /*! \brief Alignment requirement of data pointer in bytes. */
   int data_alignment;
   /*!
@@ -134,7 +134,7 @@ class Buffer : public ObjectRef {
   // User can specify data_alignment and offset_factor to be 0
   // A default value will be picked.
   TVM_DLL Buffer(Var ptr, DataType dtype, Array<PrimExpr> shape, Array<PrimExpr> strides,
-                 PrimExpr elem_offset, std::string name, std::string scope, int data_alignment,
+                 PrimExpr elem_offset, String name, String scope, int data_alignment,
                  int offset_factor, BufferType buffer_type);
 
   /*!
@@ -187,7 +187,7 @@ class Buffer : public ObjectRef {
  * \sa Buffer for complete constructor.
  */
 TVM_DLL Buffer decl_buffer(Array<PrimExpr> shape, DataType dtype = DataType::Float(32),
-                           std::string name = "buffer");
+                           String name = "buffer");
 
 /*!
  * \brief Base node for data producers.

include/tvm/tir/data_layout.h

@@ -98,7 +98,7 @@ class LayoutAxis {
 class LayoutNode : public Object {
  public:
   /*! \brief string representation of layout, "" for scalar. */
-  std::string name;
+  String name;
   /*! \brief specify each axis of the layout,
    *   in which the variable name is the name of the axis.
    *   The IterVar's extent indicates the size of the axis,

include/tvm/tir/expr.h

@@ -51,7 +51,7 @@ using FloatImmNode = tvm::FloatImmNode;
 class StringImmNode : public PrimExprNode {
  public:
   /*! \brief The constant value content. */
-  std::string value;
+  String value;
 
   void VisitAttrs(AttrVisitor* v) {
     v->Visit("dtype", &dtype);
@@ -74,7 +74,7 @@ class StringImmNode : public PrimExprNode {
  */
 class StringImm : public PrimExpr {
  public:
-  TVM_DLL StringImm(std::string value);
+  TVM_DLL StringImm(String value);
   TVM_DEFINE_OBJECT_REF_METHODS(StringImm, PrimExpr, StringImmNode);
 };
 
@@ -889,7 +889,7 @@ class CallNode : public PrimExprNode {
     PureIntrinsic = 5
   };
   /*! \brief The name of the function/intrinsic. */
-  std::string name;
+  String name;
   /*! \brief The arguments. */
   Array<PrimExpr> args;
   /*! \brief Type of calls. */
@@ -958,7 +958,7 @@ class Call : public PrimExpr {
  public:
   using CallType = CallNode::CallType;
 
-  TVM_DLL Call(DataType dtype, std::string name, Array<PrimExpr> args, CallType call_type);
+  TVM_DLL Call(DataType dtype, String name, Array<PrimExpr> args, CallType call_type);
   TVM_DEFINE_OBJECT_REF_METHODS(Call, PrimExpr, CallNode);
 };
 

include/tvm/tir/stmt.h

@@ -109,7 +109,7 @@ class AttrStmtNode : public StmtNode {
   /*! \brief this is attribute about certain node */
   ObjectRef node;
   /*! \brief the type key of the attribute */
-  std::string attr_key;
+  String attr_key;
   /*! \brief The attribute value, value is well defined at current scope. */
   PrimExpr value;
   /*! \brief The body statement to be executed */
@@ -144,7 +144,7 @@ class AttrStmtNode : public StmtNode {
  */
 class AttrStmt : public Stmt {
  public:
-  TVM_DLL AttrStmt(ObjectRef node, std::string type_key, PrimExpr value, Stmt body);
+  TVM_DLL AttrStmt(ObjectRef node, String attr_key, PrimExpr value, Stmt body);
 
   TVM_DEFINE_OBJECT_REF_METHODS(AttrStmt, Stmt, AttrStmtNode);
 };

include/tvm/tir/transform.h

@@ -54,7 +54,7 @@ using tvm::transform::Sequential;
  */
 TVM_DLL Pass CreatePrimFuncPass(
     const runtime::TypedPackedFunc<PrimFunc(PrimFunc, IRModule, PassContext)>& pass_func,
-    int opt_level, const std::string& name, const tvm::Array<runtime::String>& required);
+    int opt_level, String name, tvm::Array<String> required);
 
 /*!
  * \brief Inject prefetch instructions into stmt.
@@ -88,7 +88,7 @@ TVM_DLL Pass StorageFlatten(int cache_line_size, bool create_bound_attribute = f
  *                Expr pad_value)
  * \return The pass.
  */
-TVM_DLL Pass InjectCopyIntrin(std::string pragma_key, runtime::PackedFunc fintrin);
+TVM_DLL Pass InjectCopyIntrin(String pragma_key, runtime::PackedFunc fintrin);
 
 /*!
  * \brief Detect and insert sync points to co-processor.
@@ -103,7 +103,7 @@ TVM_DLL Pass CoProcSync();
  * \param attr_key The attribute key to be checked.
  * \return The pass.
  */
-TVM_DLL Pass LiftAttrScope(std::string attr_key);
+TVM_DLL Pass LiftAttrScope(String attr_key);
 
 /*!
  * \brief partition loops in the stmt.
@@ -222,7 +222,7 @@ TVM_DLL Pass MakePackedAPI(int num_unpacked_args);
  *
  * \return The pass.
  */
-TVM_DLL Pass RemapThreadAxis(Map<runtime::String, IterVar> axis_map);
+TVM_DLL Pass RemapThreadAxis(Map<String, IterVar> axis_map);
 
 /*!
  * \brief Lower custom datatypes.
@@ -260,7 +260,7 @@ TVM_DLL Pass SkipAssert();
  * \param storage_scope The storage scope considered.
  * \return The pass.
  */
-TVM_DLL Pass ThreadSync(std::string storage_scope);
+TVM_DLL Pass ThreadSync(String storage_scope);
 
 /*!
  * \brief Lower cross thread alleduce.

include/tvm/tir/var.h

@@ -245,7 +245,7 @@ class IterVarNode : public Object {
    * \brief additional tag on the iteration variable,
    *  set this if this is binded already to a known thread tag.
    */
-  std::string thread_tag;
+  String thread_tag;
 
   void VisitAttrs(AttrVisitor* v) {
     v->Visit("dom", &dom);
@@ -278,7 +278,7 @@ class IterVarNode : public Object {
  */
 class IterVar : public ObjectRef {
  public:
-  TVM_DLL IterVar(Range dom, Var var, IterVarType iter_type, std::string thread_tag = "");
+  TVM_DLL IterVar(Range dom, Var var, IterVarType iter_type, String thread_tag = "");
   /*!
    * \return the corresponding var in the IterVar.
    */

python/tvm/ir/json_compact.py

@@ -123,6 +123,7 @@ def _convert(item, nodes):
         "relay.IncompleteType": _rename("IncompleteType"),
         "relay.TypeRelation": _rename("TypeRelation"),
         "relay.TypeCall": _rename("TypeCall"),
+        "relay.Constructor": [_update_from_std_str("name_hint")],
         "relay.Module": _rename("IRModule"),
         "relay.SourceName": _rename("SourceName"),
         "relay.Span": _rename("Span"),
@@ -137,6 +138,11 @@ def _convert(item, nodes):
         # TIR
         "Variable": [_update_tir_var("tir.Var"), _update_from_std_str("name")],
         "SizeVar": [_update_tir_var("tir.SizeVar"), _update_from_std_str("name")],
+        "StringImm": [_update_from_std_str("value")],
+        "Call": [_update_from_std_str("name")],
+        "AttrStmt": [_update_from_std_str("attr_key")],
+        "Layout": [_update_from_std_str("name")],
+        "Buffer": [_update_from_std_str("name"), _update_from_std_str("scope")],
     }
     return create_updater(node_map, "0.6", "0.7")
 

src/ir/op.cc

@@ -134,9 +134,8 @@ ObjectPtr<Object> CreateOp(const std::string& name) {
   return Op2ObjectPtr::Get(op);
 }
 
-TVM_REGISTER_NODE_TYPE(OpNode).set_creator(CreateOp).set_repr_bytes([](const Object* n) {
-  return static_cast<const OpNode*>(n)->name;
-});
+TVM_REGISTER_NODE_TYPE(OpNode).set_creator(CreateOp).set_repr_bytes(
+    [](const Object* n) -> std::string { return static_cast<const OpNode*>(n)->name; });
 
 TVM_STATIC_IR_FUNCTOR(ReprPrinter, vtable)
     .set_dispatch<OpNode>([](const ObjectRef& ref, ReprPrinter* p) {

src/ir/transform.cc

@@ -376,16 +376,15 @@ IRModule SequentialNode::operator()(IRModule mod, const PassContext& pass_ctx) c
 }
 
 Pass CreateModulePass(const runtime::TypedPackedFunc<IRModule(IRModule, PassContext)>& pass_func,
-                      int opt_level, const String& name,
-                      const tvm::Array<runtime::String>& required) {
+                      int opt_level, String name, tvm::Array<String> required) {
   PassInfo pass_info = PassInfo(opt_level, name, required);
   return ModulePass(pass_func, pass_info);
 }
 
 TVM_REGISTER_NODE_TYPE(PassInfoNode);
 
 TVM_REGISTER_GLOBAL("transform.PassInfo")
-    .set_body_typed([](int opt_level, String name, tvm::Array<runtime::String> required) {
+    .set_body_typed([](int opt_level, String name, tvm::Array<String> required) {
       return PassInfo(opt_level, name, required);
     });