[flang][cuda] Move CUDA Fortran operations to a CUF dialect (#92317)

The number of operations dedicated to CUF grew and where all still in
FIR. In order to have a better organization, the CUF operations,
attributes and code is moved into their specific dialect and files. CUF
dialect is tightly coupled with HLFIR/FIR and their types.

The CUF attributes are bundled into their own library since some
HLFIR/FIR operations depend on them and the CUF dialect depends on the
FIR types. Without having the attributes into a separate library there
would be a dependency cycle.

Author: clementval

flang/include/flang/Lower/ConvertVariable.h

@@ -23,6 +23,10 @@
 #include "mlir/IR/Value.h"
 #include "llvm/ADT/DenseMap.h"
 
+namespace cuf {
+class DataAttributeAttr;
+}
+
 namespace fir {
 class ExtendedValue;
 class FirOpBuilder;
@@ -146,9 +150,9 @@ translateSymbolAttributes(mlir::MLIRContext *mlirContext,
 
 /// Translate the CUDA Fortran attributes of \p sym into the FIR CUDA attribute
 /// representation.
-fir::CUDADataAttributeAttr
-translateSymbolCUDADataAttribute(mlir::MLIRContext *mlirContext,
-                                 const Fortran::semantics::Symbol &sym);
+cuf::DataAttributeAttr
+translateSymbolCUFDataAttribute(mlir::MLIRContext *mlirContext,
+                                const Fortran::semantics::Symbol &sym);
 
 /// Map a symbol to a given fir::ExtendedValue. This will generate an
 /// hlfir.declare when lowering to HLFIR and map the hlfir.declare result to the

flang/include/flang/Optimizer/Builder/FIRBuilder.h

@@ -254,13 +254,13 @@ class FirOpBuilder : public mlir::OpBuilder, public mlir::OpBuilder::Listener {
                              mlir::StringAttr linkage = {},
                              mlir::Attribute value = {}, bool isConst = false,
                              bool isTarget = false,
-                             fir::CUDADataAttributeAttr cudaAttr = {});
+                             cuf::DataAttributeAttr dataAttr = {});
 
   fir::GlobalOp createGlobal(mlir::Location loc, mlir::Type type,
                              llvm::StringRef name, bool isConst, bool isTarget,
                              std::function<void(FirOpBuilder &)> bodyBuilder,
                              mlir::StringAttr linkage = {},
-                             fir::CUDADataAttributeAttr cudaAttr = {});
+                             cuf::DataAttributeAttr dataAttr = {});
 
   /// Create a global constant (read-only) value.
   fir::GlobalOp createGlobalConstant(mlir::Location loc, mlir::Type type,

flang/include/flang/Optimizer/Builder/HLFIRTools.h

@@ -239,7 +239,7 @@ genDeclare(mlir::Location loc, fir::FirOpBuilder &builder,
            const fir::ExtendedValue &exv, llvm::StringRef name,
            fir::FortranVariableFlagsAttr flags,
            mlir::Value dummyScope = nullptr,
-           fir::CUDADataAttributeAttr cudaAttr = {});
+           cuf::DataAttributeAttr dataAttr = {});
 
 /// Generate an hlfir.associate to build a variable from an expression value.
 /// The type of the variable must be provided so that scalar logicals are

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

@@ -1,3 +1,5 @@
+add_subdirectory(CUF)
+
 # 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.

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

@@ -0,0 +1,7 @@
+set(LLVM_TARGET_DEFINITIONS CUFAttr.td)
+mlir_tablegen(CUFEnumAttr.h.inc -gen-enum-decls)
+mlir_tablegen(CUFEnumAttr.cpp.inc -gen-enum-defs)
+mlir_tablegen(CUFAttr.h.inc --gen-attrdef-decls)
+mlir_tablegen(CUFAttr.cpp.inc -gen-attrdef-defs)
+
+add_public_tablegen_target(CUFAttrsIncGen)

flang/include/flang/Optimizer/Dialect/CUF/Attributes/CUFAttr.h

@@ -0,0 +1,106 @@
+//===-- Optimizer/Dialect/CUF/Attributes/CUFAttr.h -- CUF attributes ------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// Coding style: https://mlir.llvm.org/getting_started/DeveloperGuide/
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef FORTRAN_OPTIMIZER_DIALECT_CUF_CUFATTR_H
+#define FORTRAN_OPTIMIZER_DIALECT_CUF_CUFATTR_H
+
+#include "flang/Common/Fortran.h"
+#include "mlir/IR/BuiltinAttributes.h"
+
+namespace llvm {
+class StringRef;
+}
+
+#include "flang/Optimizer/Dialect/CUF/Attributes/CUFEnumAttr.h.inc"
+
+#define GET_ATTRDEF_CLASSES
+#include "flang/Optimizer/Dialect/CUF/Attributes/CUFAttr.h.inc"
+
+namespace cuf {
+
+/// Attribute to mark Fortran entities with the CUDA attribute.
+static constexpr llvm::StringRef getDataAttrName() { return "cuf.data_attr"; }
+static constexpr llvm::StringRef getProcAttrName() { return "cuf.proc_attr"; }
+
+/// Attribute to carry CUDA launch_bounds values.
+static constexpr llvm::StringRef getLaunchBoundsAttrName() {
+  return "cuf.launch_bounds";
+}
+
+/// Attribute to carry CUDA cluster_dims values.
+static constexpr llvm::StringRef getClusterDimsAttrName() {
+  return "cuf.cluster_dims";
+}
+
+inline cuf::DataAttributeAttr
+getDataAttribute(mlir::MLIRContext *mlirContext,
+                 std::optional<Fortran::common::CUDADataAttr> cudaAttr) {
+  if (cudaAttr) {
+    cuf::DataAttribute attr;
+    switch (*cudaAttr) {
+    case Fortran::common::CUDADataAttr::Constant:
+      attr = cuf::DataAttribute::Constant;
+      break;
+    case Fortran::common::CUDADataAttr::Device:
+      attr = cuf::DataAttribute::Device;
+      break;
+    case Fortran::common::CUDADataAttr::Managed:
+      attr = cuf::DataAttribute::Managed;
+      break;
+    case Fortran::common::CUDADataAttr::Pinned:
+      attr = cuf::DataAttribute::Pinned;
+      break;
+    case Fortran::common::CUDADataAttr::Shared:
+      attr = cuf::DataAttribute::Shared;
+      break;
+    case Fortran::common::CUDADataAttr::Texture:
+      // Obsolete attribute
+      return {};
+    case Fortran::common::CUDADataAttr::Unified:
+      attr = cuf::DataAttribute::Unified;
+      break;
+    }
+    return cuf::DataAttributeAttr::get(mlirContext, attr);
+  }
+  return {};
+}
+
+inline cuf::ProcAttributeAttr
+getProcAttribute(mlir::MLIRContext *mlirContext,
+                 std::optional<Fortran::common::CUDASubprogramAttrs> cudaAttr) {
+  if (cudaAttr) {
+    cuf::ProcAttribute attr;
+    switch (*cudaAttr) {
+    case Fortran::common::CUDASubprogramAttrs::Host:
+      attr = cuf::ProcAttribute::Host;
+      break;
+    case Fortran::common::CUDASubprogramAttrs::Device:
+      attr = cuf::ProcAttribute::Device;
+      break;
+    case Fortran::common::CUDASubprogramAttrs::HostDevice:
+      attr = cuf::ProcAttribute::HostDevice;
+      break;
+    case Fortran::common::CUDASubprogramAttrs::Global:
+      attr = cuf::ProcAttribute::Global;
+      break;
+    case Fortran::common::CUDASubprogramAttrs::Grid_Global:
+      attr = cuf::ProcAttribute::GridGlobal;
+      break;
+    }
+    return cuf::ProcAttributeAttr::get(mlirContext, attr);
+  }
+  return {};
+}
+
+} // namespace cuf
+
+#endif // FORTRAN_OPTIMIZER_DIALECT_CUF_CUFATTR_H

flang/include/flang/Optimizer/Dialect/CUF/Attributes/CUFAttr.td

@@ -0,0 +1,100 @@
+//===- CUFAttr.td - CUF 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
+//
+//===----------------------------------------------------------------------===//
+//
+// This file declares the CUF dialect attributes.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef FORTRAN_DIALECT_CUF_CUFATTRS
+#define FORTRAN_DIALECT_CUF_CUFATTRS
+
+include "flang/Optimizer/Dialect/CUF/CUFDialect.td"
+include "mlir/IR/EnumAttr.td"
+
+class cuf_Attr<string name> : AttrDef<CUFDialect, name>;
+
+def cuf_DataAttribute : I32EnumAttr<
+    "DataAttribute",
+    "CUDA Fortran variable attributes",
+    [
+      I32EnumAttrCase<"Constant", 0, "constant">,
+      I32EnumAttrCase<"Device", 1, "device">,
+      I32EnumAttrCase<"Managed", 2, "managed">,
+      I32EnumAttrCase<"Pinned", 3, "pinned">,
+      I32EnumAttrCase<"Shared", 4, "shared">,
+      I32EnumAttrCase<"Unified", 5, "unified">,
+      // Texture is omitted since it is obsolete and rejected by semantic.
+    ]> {
+  let genSpecializedAttr = 0;
+  let cppNamespace = "::cuf";
+}
+
+def cuf_DataAttributeAttr :
+    EnumAttr<CUFDialect, cuf_DataAttribute, "cuda"> {
+  let assemblyFormat = [{ ```<` $value `>` }];
+}
+
+def cuf_ProcAttribute : I32EnumAttr<
+    "ProcAttribute", "CUDA Fortran procedure attributes",
+    [
+      I32EnumAttrCase<"Host", 0, "host">,
+      I32EnumAttrCase<"Device", 1, "device">,
+      I32EnumAttrCase<"HostDevice", 2, "host_device">,
+      I32EnumAttrCase<"Global", 3, "global">,
+      I32EnumAttrCase<"GridGlobal", 4, "grid_global">,
+    ]> {
+  let genSpecializedAttr = 0;
+  let cppNamespace = "::cuf";
+}
+
+def cuf_ProcAttributeAttr :
+    EnumAttr<CUFDialect, cuf_ProcAttribute, "cuda_proc"> {
+  let assemblyFormat = [{ ```<` $value `>` }];
+}
+
+def cuf_LaunchBoundsAttr : cuf_Attr<"LaunchBounds"> {
+  let mnemonic = "launch_bounds";
+
+  let parameters = (ins
+    "mlir::IntegerAttr":$maxTPB,
+    "mlir::IntegerAttr":$minBPM,
+    OptionalParameter<"mlir::IntegerAttr">:$upperBoundClusterSize
+  );
+
+  let assemblyFormat = "`<` struct(params) `>`";
+}
+
+def cuf_ClusterDimsAttr : cuf_Attr<"ClusterDims"> {
+  let mnemonic = "cluster_dims";
+
+  let parameters = (ins
+    "mlir::IntegerAttr":$x,
+    "mlir::IntegerAttr":$y,
+    "mlir::IntegerAttr":$z
+  );
+
+  let assemblyFormat = "`<` struct(params) `>`";
+}
+
+def cuf_DataTransferKind : I32EnumAttr<
+    "DataTransferKind", "CUDA Fortran data transfer kind",
+    [
+      I32EnumAttrCase<"DeviceHost", 0, "device_host">,
+      I32EnumAttrCase<"HostDevice", 1, "host_device">,
+      I32EnumAttrCase<"DeviceDevice", 2, "device_device">,
+    ]> {
+  let genSpecializedAttr = 0;
+  let cppNamespace = "::cuf";
+}
+
+def cuf_DataTransferKindAttr :
+    EnumAttr<CUFDialect, cuf_DataTransferKind, "cuda_transfer"> {
+  let assemblyFormat = [{ ```<` $value `>` }];
+}
+
+#endif // FORTRAN_DIALECT_CUF_CUFATTRS

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

@@ -0,0 +1,11 @@
+add_subdirectory(Attributes)
+
+set(LLVM_TARGET_DEFINITIONS CUFDialect.td)
+mlir_tablegen(CUFDialect.h.inc -gen-dialect-decls -dialect=cuf)
+mlir_tablegen(CUFDialect.cpp.inc -gen-dialect-defs -dialect=cuf)
+
+set(LLVM_TARGET_DEFINITIONS CUFOps.td)
+mlir_tablegen(CUFOps.h.inc -gen-op-decls)
+mlir_tablegen(CUFOps.cpp.inc -gen-op-defs)
+
+add_public_tablegen_target(CUFOpsIncGen)

flang/include/flang/Optimizer/Dialect/CUF/CUFDialect.h

@@ -0,0 +1,26 @@
+//===-- Optimizer/Dialect/CUFDialect.h -- CUF dialect -----------*- 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
+//
+//===----------------------------------------------------------------------===//
+//
+// Coding style: https://mlir.llvm.org/getting_started/DeveloperGuide/
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef FORTRAN_OPTIMIZER_DIALECT_CUF_CUFDIALECT_H
+#define FORTRAN_OPTIMIZER_DIALECT_CUF_CUFDIALECT_H
+
+#include "mlir/Bytecode/BytecodeOpInterface.h"
+#include "mlir/IR/Dialect.h"
+#include "mlir/IR/SymbolTable.h"
+#include "mlir/Interfaces/CallInterfaces.h"
+#include "mlir/Interfaces/FunctionInterfaces.h"
+#include "mlir/Interfaces/LoopLikeInterface.h"
+#include "mlir/Interfaces/SideEffectInterfaces.h"
+
+#include "flang/Optimizer/Dialect/CUF/CUFDialect.h.inc"
+
+#endif // FORTRAN_OPTIMIZER_DIALECT_CUF_CUFDIALECT_H

flang/include/flang/Optimizer/Dialect/CUF/CUFDialect.td

@@ -0,0 +1,43 @@
+//===-- CUFDialect.td - CUF dialect base 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
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// Definition of the CUDA Fortran dialect
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef FORTRAN_DIALECT_CUF_CUFDIALECT
+#define FORTRAN_DIALECT_CUF_CUFDIALECT
+
+include "mlir/IR/AttrTypeBase.td"
+include "mlir/IR/EnumAttr.td"
+include "mlir/IR/OpBase.td"
+
+def CUFDialect : Dialect {
+  let name = "cuf";
+
+  let summary = "CUDA Fortran dialect";
+
+  let description = [{
+    This dialect models CUDA Fortran operations. The CUF dialect operations use
+    the FIR types and are tightly coupled with FIR and HLFIR.
+  }];
+
+  let useDefaultAttributePrinterParser = 1;
+  let usePropertiesForAttributes = 1;
+  let cppNamespace = "::cuf";
+  let dependentDialects = ["fir::FIROpsDialect"];
+
+  let extraClassDeclaration = [{
+  private:
+    // Register the CUF Attributes.
+    void registerAttributes();
+  }];
+}
+
+#endif // FORTRAN_DIALECT_CUF_CUFDIALECT

flang/include/flang/Optimizer/Dialect/CUF/CUFOps.h

@@ -0,0 +1,20 @@
+//===-- Optimizer/Dialect/CUF/CUFOps.h - CUF operations ---------*- 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 FORTRAN_OPTIMIZER_DIALECT_CUF_CUFOPS_H
+#define FORTRAN_OPTIMIZER_DIALECT_CUF_CUFOPS_H
+
+#include "flang/Optimizer/Dialect/CUF/Attributes/CUFAttr.h"
+#include "flang/Optimizer/Dialect/CUF/CUFDialect.h"
+#include "flang/Optimizer/Dialect/FIRType.h"
+#include "mlir/IR/OpDefinition.h"
+
+#define GET_OP_CLASSES
+#include "flang/Optimizer/Dialect/CUF/CUFOps.h.inc"
+
+#endif // FORTRAN_OPTIMIZER_DIALECT_CUF_CUFOPS_H