[MLIR] Add includes to PointerLikeTypeTraits where needed.

[herhut]

Summary

This is to ensure that the template declaration is seen before
any template specialization.

[ftynse]

Should we just put it in mlir/Support/LLVM.h and rely on transitivity in most cases?

[herhut]

An alternative would be to forward declare the template <typename T> struct PointerLikeTypeTraits everywhere.

[herhut]

In D75442#1900577, @ftynse wrote:

Should we just put it in mlir/Support/LLVM.h and rely on transitivity in most cases?

The transitivity in most cases is where it get complicated. I have a failure because this got included in the wrong way/order. I can put a forward declaration into LLVM.h and then include that everywhere I how have PointerLikeTypeTraits.h. Would that work better?

[ftynse]

If this fixes the build, go ahead and let's clean up later if needed.

mlir/include/mlir/Dialect/SPIRV/SPIRVOps.h

 //
 //===----------------------------------------------------------------------===//
 
 #ifndef MLIR_DIALECT_SPIRV_SPIRVOPS_H_
 #define MLIR_DIALECT_SPIRV_SPIRVOPS_H_
 
 #include "mlir/Dialect/SPIRV/SPIRVTypes.h"
 #include "mlir/IR/Function.h"
+#include "llvm/Support/PointerLikeTypeTraits.h"
 
 namespace mlir {
 class OpBuilder;
 
 namespace spirv {
 
 // TableGen'erated operation interfaces for querying versions, extensions, and
 // capabilities.

mlir/include/mlir/IR/Attributes.h

 //===- Attributes.h - MLIR Attribute Classes --------------------*- C++ -*-===//
 //
 // 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 MLIR_IR_ATTRIBUTES_H
 #define MLIR_IR_ATTRIBUTES_H
 
 #include "mlir/IR/AttributeSupport.h"
 #include "llvm/ADT/APFloat.h"
 #include "llvm/ADT/Sequence.h"
+#include "llvm/Support/PointerLikeTypeTraits.h"
 
 namespace mlir {
 class AffineMap;
 class Dialect;
 class FunctionType;
 class Identifier;
 class IntegerSet;
 class Location;

mlir/include/mlir/IR/Function.h

 #ifndef MLIR_IR_FUNCTION_H
 #define MLIR_IR_FUNCTION_H
 
 #include "mlir/Analysis/CallInterfaces.h"
 #include "mlir/IR/Block.h"
 #include "mlir/IR/FunctionSupport.h"
 #include "mlir/IR/OpDefinition.h"
 #include "mlir/IR/SymbolTable.h"
+#include "llvm/Support/PointerLikeTypeTraits.h"
 
 namespace mlir {
 //===--------------------------------------------------------------------===//
 // Function Operation.
 //===--------------------------------------------------------------------===//
 
 /// FuncOp represents a function, or an operation containing one region that
 /// forms a CFG(Control Flow Graph). The region of a function is not allowed to

mlir/include/mlir/IR/Identifier.h

 //===- Identifier.h - MLIR Identifier Class ---------------------*- C++ -*-===//
 //
 // 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 MLIR_IR_IDENTIFIER_H
 #define MLIR_IR_IDENTIFIER_H
 
 #include "mlir/Support/LLVM.h"
 #include "llvm/ADT/DenseMapInfo.h"
 #include "llvm/ADT/StringRef.h"
+#include "llvm/Support/PointerLikeTypeTraits.h"
 
 namespace mlir {
 class MLIRContext;
 
 /// This class represents a uniqued string owned by an MLIRContext.  Strings
 /// represented by this type cannot contain nul characters, and may not have a
 /// zero length.
 ///

mlir/include/mlir/IR/Location.h

 // location position information.
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef MLIR_IR_LOCATION_H
 #define MLIR_IR_LOCATION_H
 
 #include "mlir/IR/Attributes.h"
+#include "llvm/Support/PointerLikeTypeTraits.h"
 
 namespace mlir {
 
 class Attribute;
 class MLIRContext;
 class Identifier;
 
 namespace detail {

mlir/include/mlir/IR/Module.h

 //===- Module.h - MLIR Module Class -----------------------------*- C++ -*-===//
 //
 // 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
 //
 //===----------------------------------------------------------------------===//
 //
 // Module is the top-level container for code in an MLIR program.
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef MLIR_IR_MODULE_H
 #define MLIR_IR_MODULE_H
 
 #include "mlir/IR/SymbolTable.h"
+#include "llvm/Support/PointerLikeTypeTraits.h"
 
 namespace mlir {
 class ModuleTerminatorOp;
 
 //===----------------------------------------------------------------------===//
 // Module Operation.
 //===----------------------------------------------------------------------===//
 

mlir/include/mlir/IR/OpDefinition.h

 // concrete ops (like DimOp) with very little boilerplate.
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef MLIR_IR_OPDEFINITION_H
 #define MLIR_IR_OPDEFINITION_H
 
 #include "mlir/IR/Operation.h"
+#include "llvm/Support/PointerLikeTypeTraits.h"
 #include <type_traits>
 
 namespace mlir {
 class Builder;
 
 namespace OpTrait {
 template <typename ConcreteType> class OneResult;
 }

mlir/include/mlir/IR/OperationSupport.h

 
 #include "mlir/IR/Attributes.h"
 #include "mlir/IR/Identifier.h"
 #include "mlir/IR/Location.h"
 #include "mlir/IR/Types.h"
 #include "mlir/IR/Value.h"
 #include "mlir/Support/LogicalResult.h"
 #include "llvm/ADT/PointerUnion.h"
+#include "llvm/Support/PointerLikeTypeTraits.h"
 #include "llvm/Support/TrailingObjects.h"
 #include <memory>
 
 namespace mlir {
 class Block;
 class Dialect;
 class Operation;
 struct OperationState;

mlir/include/mlir/IR/Types.h

 //===- Types.h - MLIR Type Classes ------------------------------*- C++ -*-===//
 //
 // 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 MLIR_IR_TYPES_H
 #define MLIR_IR_TYPES_H
 
 #include "mlir/IR/TypeSupport.h"
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/DenseMapInfo.h"
+#include "llvm/Support/PointerLikeTypeTraits.h"
 
 namespace mlir {
 class FloatType;
 class Identifier;
 class IndexType;
 class IntegerType;
 class MLIRContext;
 class TypeStorage;

mlir/include/mlir/IR/Value.h

 //===----------------------------------------------------------------------===//
 
 #ifndef MLIR_IR_VALUE_H
 #define MLIR_IR_VALUE_H
 
 #include "mlir/IR/Types.h"
 #include "mlir/IR/UseDefLists.h"
 #include "mlir/Support/LLVM.h"
+#include "llvm/Support/PointerLikeTypeTraits.h"
 
 namespace mlir {
 class AsmState;
 class BlockArgument;
 class Operation;
 class OpResult;
 class Region;
 class Value;