[flang][NFC] Use the tablegen definition for FIR dialect (#84822)

FIROpsDialect has been declared manually with a class inheriting from
the MLIR Dialect class. Another declaration is done using tablegen here
`flang/include/flang/Optimizer/Dialect/FIRDialect.td`. This patch merge
the two declaration so we can use the tablegen generated class for all
the FIROpsDialect needs.

This is part of a series of patch to bring FIR up to date with the
current MLIR infra.

Author: clementval

flang/include/flang/Optimizer/Dialect/CMakeLists.txt

@@ -1,6 +1,10 @@
 # This replicates part of the add_mlir_dialect cmake function from MLIR that
 # cannot be used her because it expects to be run inside MLIR directory which
 # is not the case for FIR.
+set(LLVM_TARGET_DEFINITIONS FIRDialect.td)
+mlir_tablegen(FIRDialect.h.inc -gen-dialect-decls -dialect=fir)
+mlir_tablegen(FIRDialect.cpp.inc -gen-dialect-defs -dialect=fir)
+
 set(LLVM_TARGET_DEFINITIONS FIRAttr.td)
 mlir_tablegen(FIREnumAttr.h.inc -gen-enum-decls)
 mlir_tablegen(FIREnumAttr.cpp.inc -gen-enum-defs)

flang/include/flang/Optimizer/Dialect/FIRAttr.td

@@ -16,7 +16,7 @@
 include "flang/Optimizer/Dialect/FIRDialect.td"
 include "mlir/IR/EnumAttr.td"
 
-class fir_Attr<string name> : AttrDef<fir_Dialect, name>;
+class fir_Attr<string name> : AttrDef<FIROpsDialect, name>;
 
 def FIRnoAttributes  : I32BitEnumAttrCaseNone<"None">;
 def FIRallocatable  : I32BitEnumAttrCaseBit<"allocatable", 0>;
@@ -91,7 +91,7 @@ def fir_CUDADataAttribute : I32EnumAttr<
 }
 
 def fir_CUDADataAttributeAttr :
-    EnumAttr<fir_Dialect, fir_CUDADataAttribute, "cuda"> {
+    EnumAttr<FIROpsDialect, fir_CUDADataAttribute, "cuda"> {
   let assemblyFormat = [{ ```<` $value `>` }];
 }
 
@@ -109,7 +109,7 @@ def fir_CUDAProcAttribute : I32EnumAttr<
 }
 
 def fir_CUDAProcAttributeAttr :
-    EnumAttr<fir_Dialect, fir_CUDAProcAttribute, "cuda_proc"> {
+    EnumAttr<FIROpsDialect, fir_CUDAProcAttribute, "cuda_proc"> {
   let assemblyFormat = [{ ```<` $value `>` }];
 }
 

flang/include/flang/Optimizer/Dialect/FIRDialect.h

@@ -15,43 +15,14 @@
 
 #include "mlir/IR/Dialect.h"
 
+#include "flang/Optimizer/Dialect/FIRDialect.h.inc"
+
 namespace mlir {
 class IRMapping;
 } // namespace mlir
 
 namespace fir {
 
-/// FIR dialect
-class FIROpsDialect final : public mlir::Dialect {
-public:
-  explicit FIROpsDialect(mlir::MLIRContext *ctx);
-  virtual ~FIROpsDialect();
-
-  static llvm::StringRef getDialectNamespace() { return "fir"; }
-
-  mlir::Type parseType(mlir::DialectAsmParser &parser) const override;
-  void printType(mlir::Type ty, mlir::DialectAsmPrinter &p) const override;
-
-  mlir::Attribute parseAttribute(mlir::DialectAsmParser &parser,
-                                 mlir::Type type) const override;
-  void printAttribute(mlir::Attribute attr,
-                      mlir::DialectAsmPrinter &p) const override;
-
-  /// Return string name of fir.runtime attribute.
-  static constexpr llvm::StringRef getFirRuntimeAttrName() {
-    return "fir.runtime";
-  }
-
-private:
-  // Register the Attributes of this dialect.
-  void registerAttributes();
-  // Register the Types of this dialect.
-  void registerTypes();
-  // Register external interfaces on operations of
-  // this dialect.
-  void registerOpExternalInterfaces();
-};
-
 /// The FIR codegen dialect is a dialect containing a small set of transient
 /// operations used exclusively during code generation.
 class FIRCodeGenDialect final : public mlir::Dialect {

flang/include/flang/Optimizer/Dialect/FIRDialect.td

@@ -21,7 +21,7 @@ include "mlir/Interfaces/InferTypeOpInterface.td"
 include "mlir/Interfaces/LoopLikeInterface.td"
 include "mlir/Interfaces/SideEffectInterfaces.td"
 
-def fir_Dialect : Dialect {
+def FIROpsDialect : Dialect {
   let name = "fir";
   let cppNamespace = "::fir";
   let useDefaultTypePrinterParser = 0;
@@ -30,10 +30,33 @@ def fir_Dialect : Dialect {
   let dependentDialects = [
     // Arith dialect provides FastMathFlagsAttr
     // supported by some FIR operations.
-    "arith::ArithDialect",
+    "mlir::arith::ArithDialect",
     // TBAA Tag types
-    "LLVM::LLVMDialect"
+    "mlir::LLVM::LLVMDialect"
   ];
+  let extraClassDeclaration = [{
+  private:
+    // Register the builtin Attributes.
+    void registerAttributes();
+    // Register the builtin Types.
+    void registerTypes();
+    // Register external interfaces on operations of
+    // this dialect.
+    void registerOpExternalInterfaces();
+  public:
+    mlir::Type parseType(mlir::DialectAsmParser &parser) const override;
+    void printType(mlir::Type ty, mlir::DialectAsmPrinter &p) const override;
+ 
+    mlir::Attribute parseAttribute(mlir::DialectAsmParser &parser,
+                                   mlir::Type type) const override;
+    void printAttribute(mlir::Attribute attr,
+                        mlir::DialectAsmPrinter &p) const override;
+
+    // Return string name of fir.runtime attribute.
+    static constexpr llvm::StringRef getFirRuntimeAttrName() {
+      return "fir.runtime";
+    }
+  }];
 }
 
 #endif // FORTRAN_DIALECT_FIR_DIALECT

flang/include/flang/Optimizer/Dialect/FIROps.td

@@ -27,7 +27,7 @@ include "mlir/IR/BuiltinAttributes.td"
 // Base class for FIR operations.
 // All operations automatically get a prefix of "fir.".
 class fir_Op<string mnemonic, list<Trait> traits>
-  : Op<fir_Dialect, mnemonic, traits>;
+  : Op<FIROpsDialect, mnemonic, traits>;
 
 // Base class for FIR operations that take a single argument
 class fir_SimpleOp<string mnemonic, list<Trait> traits>

flang/include/flang/Optimizer/Dialect/FIRTypes.td

@@ -22,7 +22,7 @@ include "flang/Optimizer/Dialect/FIRDialect.td"
 
 class FIR_Type<string name, string typeMnemonic, list<Trait> traits = [],
                string baseCppClass = "::mlir::Type">
-    : TypeDef<fir_Dialect, name, traits, baseCppClass> {
+    : TypeDef<FIROpsDialect, name, traits, baseCppClass> {
   let mnemonic = typeMnemonic;
 }
 

flang/lib/Optimizer/Dialect/FIRDialect.cpp

@@ -18,6 +18,8 @@
 #include "mlir/Target/LLVMIR/ModuleTranslation.h"
 #include "mlir/Transforms/InliningUtils.h"
 
+#include "flang/Optimizer/Dialect/FIRDialect.cpp.inc"
+
 using namespace fir;
 
 namespace {
@@ -58,9 +60,7 @@ struct FIRInlinerInterface : public mlir::DialectInlinerInterface {
 };
 } // namespace
 
-fir::FIROpsDialect::FIROpsDialect(mlir::MLIRContext *ctx)
-    : mlir::Dialect("fir", ctx, mlir::TypeID::get<FIROpsDialect>()) {
-  getContext()->loadDialect<mlir::LLVM::LLVMDialect>();
+void fir::FIROpsDialect::initialize() {
   registerTypes();
   registerAttributes();
   addOperations<
@@ -94,11 +94,6 @@ void fir::addFIRToLLVMIRExtension(mlir::DialectRegistry &registry) {
       });
 }
 
-// anchor the class vtable to this compilation unit
-fir::FIROpsDialect::~FIROpsDialect() {
-  // do nothing
-}
-
 mlir::Type fir::FIROpsDialect::parseType(mlir::DialectAsmParser &parser) const {
   return parseFirType(const_cast<FIROpsDialect *>(this), parser);
 }