[mlir][ods][NFC] Move enum attribute definitions from OpBase.td to EnumAttr.td

[jfurtek]

Summary

This diff moves EnumAttr tablegen definitions (specifically, IntEnumAttr and
BitEnumAttr-related classes) from OpBase.td to EnumAttr.td. No
functionality is changed.

[rriddle]

Thanks! Very appreciated.

mlir/include/mlir/Dialect/Arithmetic/IR/ArithmeticBase.td

14

Can we keep these sorted? Same in several other places.

[jfurtek]

Update include sort errors

[jfurtek]

• Fix include sorting

[jfurtek]

I don't have commit privileges - it would be great if someone could merge this when convenient.

[mehdi_amini]

Can you rebase?

[jfurtek]

• Fix include sorting
• Remove defunct string attribute from attribute classes being moved
• Rebase

mlir/include/mlir/Dialect/Arithmetic/IR/ArithmeticBase.td

 //===- ArithmeticBase.td - Base defs for arith dialect ------*- tablegen -*-==//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef ARITHMETIC_BASE
 #define ARITHMETIC_BASE
 
+include "mlir/IR/EnumAttr.td"
 include "mlir/IR/OpBase.td"
 
 def Arithmetic_Dialect : Dialect {
   let name = "arith";
   let cppNamespace = "::mlir::arith";
   let description = [{
     The arithmetic dialect is intended to hold basic integer and floating point
     mathematical operations. This includes unary, binary, and ternary arithmetic
     ops, bitwise and shift ops, cast ops, and compare ops. Operations in this
     dialect also accept vectors and tensors of integers or floats.

mlir/include/mlir/Dialect/GPU/ParallelLoopMapperAttr.td

 // gpu.launch operations
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef PARALLEL_LOOP_MAPPER_ATTR
 #define PARALLEL_LOOP_MAPPER_ATTR
 
 include "mlir/Dialect/GPU/GPUBase.td"
+include "mlir/IR/EnumAttr.td"
 
 def BlockX : I64EnumAttrCase<"BlockX", 0>;
 def BlockY : I64EnumAttrCase<"BlockY", 1>;
 def BlockZ : I64EnumAttrCase<"BlockZ", 2>;
 def ThreadX : I64EnumAttrCase<"ThreadX", 3>;
 def ThreadY : I64EnumAttrCase<"ThreadY", 4>;
 def ThreadZ : I64EnumAttrCase<"ThreadZ", 5>;
 def Sequential : I64EnumAttrCase<"Sequential", 6>;

mlir/include/mlir/Dialect/LLVMIR/LLVMOpBase.td

 //===-- LLVMOpBase.td - LLVM IR dialect shared definitions -*- tablegen -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 //
 // This file contains shared definitions for the LLVM IR dialect and its
 // subdialects.
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef LLVMIR_OP_BASE
 #define LLVMIR_OP_BASE
 
+include "mlir/IR/EnumAttr.td"
 include "mlir/IR/OpBase.td"
 include "mlir/Interfaces/SideEffectInterfaces.td"
 
 //===----------------------------------------------------------------------===//
 // LLVM Dialect.
 //===----------------------------------------------------------------------===//
 
 def LLVM_Dialect : Dialect {

mlir/include/mlir/Dialect/Vector/IR/VectorOps.td

 //===- VectorOps.td - Vector op definitions ---------------*- tablegen -*-====//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 //
 // Defines MLIR vector operations.
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef VECTOR_OPS
 #define VECTOR_OPS
 
+include "mlir/IR/EnumAttr.td"
 include "mlir/Interfaces/InferTypeOpInterface.td"
 include "mlir/Interfaces/SideEffectInterfaces.td"
 include "mlir/Interfaces/VectorInterfaces.td"
 include "mlir/Interfaces/ViewLikeInterface.td"
 
 def Vector_Dialect : Dialect {
   let name = "vector";
   let cppNamespace = "::mlir::vector";

mlir/include/mlir/IR/EnumAttr.td

 //===-- EnumAttr.td - Enum attributes ----------------------*- tablegen -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef ENUMATTR_TD
 #define ENUMATTR_TD
 
 include "mlir/IR/AttrTypeBase.td"
 
+//===----------------------------------------------------------------------===//
+// Enum attribute kinds
+
+// Additional information for an enum attribute case.
+class EnumAttrCaseInfo<string sym, int intVal, string strVal> {
+  // The C++ enumerant symbol.
+  string symbol = sym;
+
+  // The C++ enumerant value.
+  // If less than zero, there will be no explicit discriminator values assigned
+  // to enumerators in the generated enum class.
+  int value = intVal;
+
+  // The string representation of the enumerant. May be the same as symbol.
+  string str = strVal;
+}
+
+// An enum attribute case stored with StringAttr.
+class StrEnumAttrCase<string sym, int val = -1, string str = sym> :
+    EnumAttrCaseInfo<sym, val, str>,
+    StringBasedAttr<
+      CPred<"$_self.cast<::mlir::StringAttr>().getValue() == \"" # str # "\"">,
+      "case " # str>;
+
+// An enum attribute case stored with IntegerAttr, which has an integer value,
+// its representation as a string and a C++ symbol name which may be different.
+class IntEnumAttrCaseBase<I intType, string sym, string strVal, int intVal> :
+    EnumAttrCaseInfo<sym, intVal, strVal>,
+    SignlessIntegerAttrBase<intType, "case " # strVal> {
+  let predicate =
+    CPred<"$_self.cast<::mlir::IntegerAttr>().getInt() == " # intVal>;
+}
+
+// Cases of integer enum attributes with a specific type. By default, the string
+// representation is the same as the C++ symbol name.
+class I32EnumAttrCase<string sym, int val, string str = sym>
+    : IntEnumAttrCaseBase<I32, sym, str, val>;
+class I64EnumAttrCase<string sym, int val, string str = sym>
+    : IntEnumAttrCaseBase<I64, sym, str, val>;
+
+// A bit enum case stored with an IntegerAttr. `val` here is *not* the ordinal
+// number of a bit that is set. It is an integer value with bits set to match
+// the case.
+class BitEnumAttrCaseBase<I intType, string sym, int val, string str = sym> :
+    EnumAttrCaseInfo<sym, val, str>,
+    SignlessIntegerAttrBase<intType, "case " #str>;
+
+// A bit enum case stored with a 32-bit IntegerAttr. `val` here is *not* the
+// ordinal number of a bit that is set. It is a 32-bit integer value with bits
+// set to match the case. 
+class I32BitEnumAttrCase<string sym, int val, string str = sym>
+    : BitEnumAttrCaseBase<I32, sym, val, str>;
+
+// A bit enum case stored with a 64-bit IntegerAttr. `val` here is *not* the
+// ordinal number of a bit that is set. It is a 64-bit integer value with bits
+// bits set to match the case.
+class I64BitEnumAttrCase<string sym, int val, string str = sym>
+    : BitEnumAttrCaseBase<I64, sym, val, str>;
+
+// The special bit enum case for I32 with no bits set (i.e. value = 0).
+class I32BitEnumAttrCaseNone<string sym, string str = sym>
+    : I32BitEnumAttrCase<sym, 0, str>;
+
+// The special bit enum case for I64 with no bits set (i.e. value = 0).
+class I64BitEnumAttrCaseNone<string sym, string str = sym>
+    : I64BitEnumAttrCase<sym, 0, str>;
+
+// A bit enum case for a single bit, specified by a bit position.
+// The pos argument refers to the index of the bit, and is limited
+// to be in the range [0, bitwidth).
+class BitEnumAttrCaseBit<I intType, string sym, int pos, string str = sym>
+    : BitEnumAttrCaseBase<intType, sym, !shl(1, pos), str> {
+  assert !and(!ge(pos, 0), !lt(pos, intType.bitwidth)),
+      "bit position larger than underlying storage";
+}
+
+// A bit enum case for a single bit in a 32-bit enum, specified by the
+// bit position.
+class I32BitEnumAttrCaseBit<string sym, int pos, string str = sym>
+    : BitEnumAttrCaseBit<I32, sym, pos, str>;
+
+// A bit enum case for a single bit in a 64-bit enum, specified by the
+// bit position.
+class I64BitEnumAttrCaseBit<string sym, int pos, string str = sym>
+    : BitEnumAttrCaseBit<I64, sym, pos, str>;
+
+
+// A bit enum case for a group/list of previously declared cases, providing
+// a convenient alias for that group.
+class BitEnumAttrCaseGroup<I intType, string sym,
+                           list<BitEnumAttrCaseBase> cases, string str = sym>
+    : BitEnumAttrCaseBase<intType, sym,
+          !foldl(0, cases, value, bitcase, !or(value, bitcase.value)),
+          str>;
+
+// A 32-bit enum case for a group/list of previously declared cases, providing
+// a convenient alias for that group.
+class I32BitEnumAttrCaseGroup<string sym, list<BitEnumAttrCaseBase> cases,
+                              string str = sym>
+    : BitEnumAttrCaseGroup<I32, sym, cases, str>;
+
+// A 64-bit enum case for a group/list of previously declared cases, providing
+// a convenient alias for that group.
+class I64BitEnumAttrCaseGroup<string sym, list<BitEnumAttrCaseBase> cases,
+                              string str = sym>
+    : BitEnumAttrCaseGroup<I64, sym, cases, str>;
+
+// Additional information for an enum attribute.
+class EnumAttrInfo<
+    string name, list<EnumAttrCaseInfo> cases, Attr baseClass> :
+      Attr<baseClass.predicate, baseClass.summary> {
+  // The C++ enum class name
+  string className = name;
+
+  // List of all accepted cases
+  list<EnumAttrCaseInfo> enumerants = cases;
+
+  // The following fields are only used by the EnumsGen backend to generate
+  // an enum class definition and conversion utility functions.
+
+  // The underlying type for the C++ enum class. An empty string mean the
+  // underlying type is not explicitly specified.
+  string underlyingType = "";
+
+  // The name of the utility function that converts a value of the underlying
+  // type to the corresponding symbol. It will have the following signature:
+  //
+  // ```c++
+  // llvm::Optional<<qualified-enum-class-name>> <fn-name>(<underlying-type>);
+  // ```
+  string underlyingToSymbolFnName = "symbolize" # name;
+
+  // The name of the utility function that converts a string to the
+  // corresponding symbol. It will have the following signature:
+  //
+  // ```c++
+  // llvm::Optional<<qualified-enum-class-name>> <fn-name>(llvm::StringRef);
+  // ```
+  string stringToSymbolFnName = "symbolize" # name;
+
+  // The name of the utility function that converts a symbol to the
+  // corresponding string. It will have the following signature:
+  //
+  // ```c++
+  // <return-type> <fn-name>(<qualified-enum-class-name>);
+  // ```
+  string symbolToStringFnName = "stringify" # name;
+  string symbolToStringFnRetType = "::llvm::StringRef";
+
+  // The name of the utility function that returns the max enum value used
+  // within the enum class. It will have the following signature:
+  //
+  // ```c++
+  // static constexpr unsigned <fn-name>();
+  // ```
+  string maxEnumValFnName = "getMaxEnumValFor" # name;
+
+  // Generate specialized Attribute class
+  bit genSpecializedAttr = 1;
+  // The underlying Attribute class, which holds the enum value
+  Attr baseAttrClass = baseClass;
+  // The name of specialized Enum Attribute class
+  string specializedAttrClassName = name # Attr;
+
+  // Override Attr class fields for specialized class
+  let predicate = !if(genSpecializedAttr,
+    CPred<"$_self.isa<" # cppNamespace # "::" # specializedAttrClassName # ">()">,
+    baseAttrClass.predicate);
+  let storageType = !if(genSpecializedAttr,
+    cppNamespace # "::" # specializedAttrClassName,
+    baseAttrClass.storageType);
+  let returnType = !if(genSpecializedAttr,
+    cppNamespace # "::" # className,
+    baseAttrClass.returnType);
+  let constBuilderCall = !if(genSpecializedAttr,
+    cppNamespace # "::" # specializedAttrClassName # "::get($_builder.getContext(), $0)",
+    baseAttrClass.constBuilderCall);
+  let valueType = baseAttrClass.valueType;
+}
+
+// An enum attribute backed by StringAttr.
+//
+// Op attributes of this kind are stored as StringAttr. Extra verification will
+// be generated on the string though: only the symbols of the allowed cases are
+// permitted as the string value.
+class StrEnumAttr<string name, string summary, list<StrEnumAttrCase> cases> :
+  EnumAttrInfo<name, cases,
+    StringBasedAttr<
+      And<[StrAttr.predicate, Or<!foreach(case, cases, case.predicate)>]>,
+      !if(!empty(summary), "allowed string cases: " #
+          !interleave(!foreach(case, cases, "'" # case.symbol # "'"), ", "),
+          summary)>> {
+  // Disable specialized Attribute class for `StringAttr` backend by default.
+  let genSpecializedAttr = 0;
+}
+
+// An enum attribute backed by IntegerAttr.
+//
+// Op attributes of this kind are stored as IntegerAttr. Extra verification will
+// be generated on the integer though: only the values of the allowed cases are
+// permitted as the integer value.
+class IntEnumAttrBase<I intType, list<IntEnumAttrCaseBase> cases, string summary> :
+    SignlessIntegerAttrBase<intType, summary> {
+  let predicate = And<[
+    SignlessIntegerAttrBase<intType, summary>.predicate,
+    Or<!foreach(case, cases, case.predicate)>]>;
+}
+
+class IntEnumAttr<I intType, string name, string summary,
+                  list<IntEnumAttrCaseBase> cases> :
+  EnumAttrInfo<name, cases,
+    IntEnumAttrBase<intType, cases,
+      !if(!empty(summary), "allowed " # intType.summary # " cases: " #
+          !interleave(!foreach(case, cases, case.value), ", "),
+          summary)>>;
+
+class I32EnumAttr<string name, string summary, list<I32EnumAttrCase> cases> :
+    IntEnumAttr<I32, name, summary, cases> {
+  let underlyingType = "uint32_t";
+}
+class I64EnumAttr<string name, string summary, list<I64EnumAttrCase> cases> :
+    IntEnumAttr<I64, name, summary, cases> {
+  let underlyingType = "uint64_t";
+}
+
+// A bit enum stored with an IntegerAttr.
+//
+// Op attributes of this kind are stored as IntegerAttr. Extra verification will
+// be generated on the integer to make sure only allowed bits are set. Besides,
+// helper methods are generated to parse a string separated with a specified
+// delimiter to a symbol and vice versa.
+class BitEnumAttrBase<I intType, list<BitEnumAttrCaseBase> cases,
+                      string summary>
+    : SignlessIntegerAttrBase<intType, summary> {
+  let predicate = And<[
+    SignlessIntegerAttrBase<intType, summary>.predicate,
+    // Make sure we don't have unknown bit set.
+    CPred<"!($_self.cast<::mlir::IntegerAttr>().getValue().getZExtValue() & (~("
+          # !interleave(!foreach(case, cases, case.value # "u"), "|") #
+          ")))">
+  ]>;
+}
+
+class BitEnumAttr<I intType, string name, string summary,
+                  list<BitEnumAttrCaseBase> cases>
+    : EnumAttrInfo<name, cases, BitEnumAttrBase<intType, cases, summary>> {
+  // Determine "valid" bits from enum cases for error checking
+  int validBits = !foldl(0, cases, value, bitcase, !or(value, bitcase.value));
+
+  // We need to return a string because we may concatenate symbols for multiple
+  // bits together.
+  let symbolToStringFnRetType = "std::string";
+
+  // The delimiter used to separate bit enum cases in strings.
+  string separator = "|";
+}
+
+class I32BitEnumAttr<string name, string summary,
+                     list<BitEnumAttrCaseBase> cases>
+    : BitEnumAttr<I32, name, summary, cases> {
+  let underlyingType = "uint32_t";
+}
+
+class I64BitEnumAttr<string name, string summary,
+                     list<BitEnumAttrCaseBase> cases>
+    : BitEnumAttr<I64, name, summary, cases> {
+  let underlyingType = "uint64_t";
+}
+
 // A C++ enum as an attribute parameter. The parameter implements a parser and
 // printer for the enum by dispatching calls to `stringToSymbol` and
 // `symbolToString`.
 class EnumParameter<EnumAttrInfo enumInfo>
     : AttrParameter<enumInfo.cppNamespace # "::" # enumInfo.className,
                     "an enum of type " # enumInfo.className> {
   // Parse a keyword and pass it to `stringToSymbol`. Emit an error if a the
   // symbol is not valid.

mlir/include/mlir/IR/OpBase.td

def UnitAttr : Attr<CPred<"$_self.isa<::mlir::UnitAttr>()">, "unit attribute"> {
   let constBuilderCall = "$_builder.getUnitAttr()";
   let convertFromStorage = "$_self != nullptr";
   let returnType = "bool";
   let valueType = NoneType;
   let isOptional = 1;
 }
 
 //===----------------------------------------------------------------------===//
-// Enum attribute kinds
-
-// Additional information for an enum attribute case.
-class EnumAttrCaseInfo<string sym, int intVal, string strVal> {
-  // The C++ enumerant symbol.
-  string symbol = sym;
-
-  // The C++ enumerant value.
-  // If less than zero, there will be no explicit discriminator values assigned
-  // to enumerators in the generated enum class.
-  int value = intVal;
-
-  // The string representation of the enumerant. May be the same as symbol.
-  string str = strVal;
-}
-
-// An enum attribute case stored with StringAttr.
-class StrEnumAttrCase<string sym, int val = -1, string str = sym> :
-    EnumAttrCaseInfo<sym, val, str>,
-    StringBasedAttr<
-      CPred<"$_self.cast<::mlir::StringAttr>().getValue() == \"" # str # "\"">,
-      "case " # str>;
-
-// An enum attribute case stored with IntegerAttr, which has an integer value,
-// its representation as a string and a C++ symbol name which may be different.
-class IntEnumAttrCaseBase<I intType, string sym, string strVal, int intVal> :
-    EnumAttrCaseInfo<sym, intVal, strVal>,
-    SignlessIntegerAttrBase<intType, "case " # strVal> {
-  let predicate =
-    CPred<"$_self.cast<::mlir::IntegerAttr>().getInt() == " # intVal>;
-}
-
-// Cases of integer enum attributes with a specific type. By default, the string
-// representation is the same as the C++ symbol name.
-class I32EnumAttrCase<string sym, int val, string str = sym>
-    : IntEnumAttrCaseBase<I32, sym, str, val>;
-class I64EnumAttrCase<string sym, int val, string str = sym>
-    : IntEnumAttrCaseBase<I64, sym, str, val>;
-
-// A bit enum case stored with an IntegerAttr. `val` here is *not* the ordinal
-// number of a bit that is set. It is an integer value with bits set to match
-// the case.
-class BitEnumAttrCaseBase<I intType, string sym, int val, string str = sym> :
-    EnumAttrCaseInfo<sym, val, str>,
-    SignlessIntegerAttrBase<intType, "case " #str>;
-
-// A bit enum case stored with a 32-bit IntegerAttr. `val` here is *not* the
-// ordinal number of a bit that is set. It is a 32-bit integer value with bits
-// set to match the case. 
-class I32BitEnumAttrCase<string sym, int val, string str = sym>
-    : BitEnumAttrCaseBase<I32, sym, val, str>;
-
-// A bit enum case stored with a 64-bit IntegerAttr. `val` here is *not* the
-// ordinal number of a bit that is set. It is a 64-bit integer value with bits
-// bits set to match the case.
-class I64BitEnumAttrCase<string sym, int val, string str = sym>
-    : BitEnumAttrCaseBase<I64, sym, val, str>;
-
-// The special bit enum case for I32 with no bits set (i.e. value = 0).
-class I32BitEnumAttrCaseNone<string sym, string str = sym>
-    : I32BitEnumAttrCase<sym, 0, str>;
-
-// The special bit enum case for I64 with no bits set (i.e. value = 0).
-class I64BitEnumAttrCaseNone<string sym, string str = sym>
-    : I64BitEnumAttrCase<sym, 0, str>;
-
-// A bit enum case for a single bit, specified by a bit position.
-// The pos argument refers to the index of the bit, and is limited
-// to be in the range [0, bitwidth).
-class BitEnumAttrCaseBit<I intType, string sym, int pos, string str = sym>
-    : BitEnumAttrCaseBase<intType, sym, !shl(1, pos), str> {
-  assert !and(!ge(pos, 0), !lt(pos, intType.bitwidth)),
-      "bit position larger than underlying storage";
-}
-
-// A bit enum case for a single bit in a 32-bit enum, specified by the
-// bit position.
-class I32BitEnumAttrCaseBit<string sym, int pos, string str = sym>
-    : BitEnumAttrCaseBit<I32, sym, pos, str>;
-
-// A bit enum case for a single bit in a 64-bit enum, specified by the
-// bit position.
-class I64BitEnumAttrCaseBit<string sym, int pos, string str = sym>
-    : BitEnumAttrCaseBit<I64, sym, pos, str>;
-
-
-// A bit enum case for a group/list of previously declared cases, providing
-// a convenient alias for that group.
-class BitEnumAttrCaseGroup<I intType, string sym,
-                           list<BitEnumAttrCaseBase> cases, string str = sym>
-    : BitEnumAttrCaseBase<intType, sym,
-          !foldl(0, cases, value, bitcase, !or(value, bitcase.value)),
-          str>;
-
-// A 32-bit enum case for a group/list of previously declared cases, providing
-// a convenient alias for that group.
-class I32BitEnumAttrCaseGroup<string sym, list<BitEnumAttrCaseBase> cases,
-                              string str = sym>
-    : BitEnumAttrCaseGroup<I32, sym, cases, str>;
-
-// A 64-bit enum case for a group/list of previously declared cases, providing
-// a convenient alias for that group.
-class I64BitEnumAttrCaseGroup<string sym, list<BitEnumAttrCaseBase> cases,
-                              string str = sym>
-    : BitEnumAttrCaseGroup<I64, sym, cases, str>;
-
-// Additional information for an enum attribute.
-class EnumAttrInfo<
-    string name, list<EnumAttrCaseInfo> cases, Attr baseClass> :
-      Attr<baseClass.predicate, baseClass.summary> {
-  // The C++ enum class name
-  string className = name;
-
-  // List of all accepted cases
-  list<EnumAttrCaseInfo> enumerants = cases;
-
-  // The following fields are only used by the EnumsGen backend to generate
-  // an enum class definition and conversion utility functions.
-
-  // The underlying type for the C++ enum class. An empty string mean the
-  // underlying type is not explicitly specified.
-  string underlyingType = "";
-
-  // The name of the utility function that converts a value of the underlying
-  // type to the corresponding symbol. It will have the following signature:
-  //
-  // ```c++
-  // llvm::Optional<<qualified-enum-class-name>> <fn-name>(<underlying-type>);
-  // ```
-  string underlyingToSymbolFnName = "symbolize" # name;
-
-  // The name of the utility function that converts a string to the
-  // corresponding symbol. It will have the following signature:
-  //
-  // ```c++
-  // llvm::Optional<<qualified-enum-class-name>> <fn-name>(llvm::StringRef);
-  // ```
-  string stringToSymbolFnName = "symbolize" # name;
-
-  // The name of the utility function that converts a symbol to the
-  // corresponding string. It will have the following signature:
-  //
-  // ```c++
-  // <return-type> <fn-name>(<qualified-enum-class-name>);
-  // ```
-  string symbolToStringFnName = "stringify" # name;
-  string symbolToStringFnRetType = "::llvm::StringRef";
-
-  // The name of the utility function that returns the max enum value used
-  // within the enum class. It will have the following signature:
-  //
-  // ```c++
-  // static constexpr unsigned <fn-name>();
-  // ```
-  string maxEnumValFnName = "getMaxEnumValFor" # name;
-
-  // Generate specialized Attribute class
-  bit genSpecializedAttr = 1;
-  // The underlying Attribute class, which holds the enum value
-  Attr baseAttrClass = baseClass;
-  // The name of specialized Enum Attribute class
-  string specializedAttrClassName = name # Attr;
-
-  // Override Attr class fields for specialized class
-  let predicate = !if(genSpecializedAttr,
-    CPred<"$_self.isa<" # cppNamespace # "::" # specializedAttrClassName # ">()">,
-    baseAttrClass.predicate);
-  let storageType = !if(genSpecializedAttr,
-    cppNamespace # "::" # specializedAttrClassName,
-    baseAttrClass.storageType);
-  let returnType = !if(genSpecializedAttr,
-    cppNamespace # "::" # className,
-    baseAttrClass.returnType);
-  let constBuilderCall = !if(genSpecializedAttr,
-    cppNamespace # "::" # specializedAttrClassName # "::get($_builder.getContext(), $0)",
-    baseAttrClass.constBuilderCall);
-  let valueType = baseAttrClass.valueType;
-}
-
-// An enum attribute backed by StringAttr.
-//
-// Op attributes of this kind are stored as StringAttr. Extra verification will
-// be generated on the string though: only the symbols of the allowed cases are
-// permitted as the string value.
-class StrEnumAttr<string name, string summary, list<StrEnumAttrCase> cases> :
-  EnumAttrInfo<name, cases,
-    StringBasedAttr<
-      And<[StrAttr.predicate, Or<!foreach(case, cases, case.predicate)>]>,
-      !if(!empty(summary), "allowed string cases: " #
-          !interleave(!foreach(case, cases, "'" # case.symbol # "'"), ", "),
-          summary)>> {
-  // Disable specialized Attribute class for `StringAttr` backend by default.
-  let genSpecializedAttr = 0;
-}
-
-// An enum attribute backed by IntegerAttr.
-//
-// Op attributes of this kind are stored as IntegerAttr. Extra verification will
-// be generated on the integer though: only the values of the allowed cases are
-// permitted as the integer value.
-class IntEnumAttrBase<I intType, list<IntEnumAttrCaseBase> cases, string summary> :
-    SignlessIntegerAttrBase<intType, summary> {
-  let predicate = And<[
-    SignlessIntegerAttrBase<intType, summary>.predicate,
-    Or<!foreach(case, cases, case.predicate)>]>;
-}
-
-class IntEnumAttr<I intType, string name, string summary,
-                  list<IntEnumAttrCaseBase> cases> :
-  EnumAttrInfo<name, cases,
-    IntEnumAttrBase<intType, cases,
-      !if(!empty(summary), "allowed " # intType.summary # " cases: " #
-          !interleave(!foreach(case, cases, case.value), ", "),
-          summary)>>;
-
-class I32EnumAttr<string name, string summary, list<I32EnumAttrCase> cases> :
-    IntEnumAttr<I32, name, summary, cases> {
-  let underlyingType = "uint32_t";
-}
-class I64EnumAttr<string name, string summary, list<I64EnumAttrCase> cases> :
-    IntEnumAttr<I64, name, summary, cases> {
-  let underlyingType = "uint64_t";
-}
-
-// A bit enum stored with an IntegerAttr.
-//
-// Op attributes of this kind are stored as IntegerAttr. Extra verification will
-// be generated on the integer to make sure only allowed bits are set. Besides,
-// helper methods are generated to parse a string separated with a specified
-// delimiter to a symbol and vice versa.
-class BitEnumAttrBase<I intType, list<BitEnumAttrCaseBase> cases,
-                      string summary>
-    : SignlessIntegerAttrBase<intType, summary> {
-  let predicate = And<[
-    SignlessIntegerAttrBase<intType, summary>.predicate,
-    // Make sure we don't have unknown bit set.
-    CPred<"!($_self.cast<::mlir::IntegerAttr>().getValue().getZExtValue() & (~("
-          # !interleave(!foreach(case, cases, case.value # "u"), "|") #
-          ")))">
-  ]>;
-}
-
-class BitEnumAttr<I intType, string name, string summary,
-                  list<BitEnumAttrCaseBase> cases>
-    : EnumAttrInfo<name, cases, BitEnumAttrBase<intType, cases, summary>> {
-  // Determine "valid" bits from enum cases for error checking
-  int validBits = !foldl(0, cases, value, bitcase, !or(value, bitcase.value));
-
-  // We need to return a string because we may concatenate symbols for multiple
-  // bits together.
-  let symbolToStringFnRetType = "std::string";
-
-  // The delimiter used to separate bit enum cases in strings.
-  string separator = "|";
-}
-
-class I32BitEnumAttr<string name, string summary,
-                     list<BitEnumAttrCaseBase> cases>
-    : BitEnumAttr<I32, name, summary, cases> {
-  let underlyingType = "uint32_t";
-}
-
-class I64BitEnumAttr<string name, string summary,
-                     list<BitEnumAttrCaseBase> cases>
-    : BitEnumAttr<I64, name, summary, cases> {
-  let underlyingType = "uint64_t";
-}
-
-//===----------------------------------------------------------------------===//
 // Composite attribute kinds
 
 class DictionaryAttrBase<Pred condition, string summary> :
     Attr<condition, summary> {
   let storageType = [{ ::mlir::DictionaryAttr }];
   let returnType = [{ ::mlir::DictionaryAttr }];
   let valueType = NoneType;
   let convertFromStorage = "$_self";

mlir/test/mlir-tblgen/op-attribute.td

 // RUN: mlir-tblgen -gen-op-decls -I %S/../../include %s | FileCheck %s --check-prefix=DECL
 // RUN: mlir-tblgen -gen-op-defs -I %S/../../include %s | FileCheck %s --check-prefix=DEF
 // RUN: mlir-tblgen -print-records -I %S/../../include %s | FileCheck %s --check-prefix=RECORD
 
 include "mlir/IR/AttrTypeBase.td"
+include "mlir/IR/EnumAttr.td"
 include "mlir/IR/OpBase.td"
 
 def Test_Dialect : Dialect {
   let name = "test";
   let cppNamespace = "foobar";
 }
 class NS_Op<string mnemonic, list<Trait> traits> :
     Op<Test_Dialect, mnemonic, traits>;

mlir/unittests/TableGen/enums.td

 //===-- enums.td - EnumsGen test definition file -----------*- tablegen -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
+include "mlir/IR/EnumAttr.td"
 include "mlir/IR/OpBase.td"
 
 def CaseA: StrEnumAttrCase<"CaseA">;
 def CaseB: StrEnumAttrCase<"CaseB", 10>;
 
 def StrEnum: StrEnumAttr<"StrEnum", "A test enum", [CaseA, CaseB]> {
   let cppNamespace = "Outer::Inner";
   let stringToSymbolFnName = "ConvertToEnum";