[Mlir-commits] [mlir] Reimplementing target description concept using DLTI attribute (PR #92138)

[Niranjan Hasabnis]

================
@@ -0,0 +1,207 @@
+//===- DLTIAttrs.td - DLTI dialect attributes definition --*- 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 MLIR_DIALECT_DLTI_DLTIATTRS_TD
+#define MLIR_DIALECT_DLTI_DLTIATTRS_TD
+
+include "mlir/Dialect/DLTI/DLTI.td"
+include "mlir/IR/AttrTypeBase.td"
+
+class DLTIAttr<string name, list<Trait> traits = [],
+                string baseCppClass = "::mlir::Attribute">
+    : AttrDef<DLTI_Dialect, name, traits, baseCppClass> { }
+
+//===----------------------------------------------------------------------===//
+// DataLayoutEntryAttr
+//===----------------------------------------------------------------------===//
+
+def DataLayoutEntryTrait
+    : NativeAttrTrait<"DataLayoutEntryInterface::Trait"> {
+  let cppNamespace = "::mlir";
+}
+
+def DLTI_DataLayoutEntryAttr :
+    DLTIAttr<"DataLayoutEntry", [DataLayoutEntryTrait]> {
+  let summary = [{
+    An attribute to represent an entry of a data layout specification.
+  }];
+  let description = [{
+    A data layout entry attribute is a key-value pair where the key is a type or
+    an identifier and the value is another attribute. These entries form a data
+    layout specification.
+  }];
+  let parameters = (ins
+    "DataLayoutEntryKey":$key, "Attribute":$value
+  );
+  // TODO: We do not generate storage class because llvm::PointerUnion
+  // does not work with hash_key method.
+  let genStorageClass = 0;
+  let mnemonic = "dl_entry";
+  let genVerifyDecl = 0;
+  let hasCustomAssemblyFormat = 1;
+  let extraClassDeclaration = [{
+    /// Returns the entry with the given key and value.
+    static DataLayoutEntryAttr get(StringAttr key, Attribute value);
+    static DataLayoutEntryAttr get(MLIRContext *context, Type key, Attribute value);
+    static DataLayoutEntryAttr get(Type key, Attribute value);
+  }];
+}
+
+//===----------------------------------------------------------------------===//
+// DataLayoutSpecAttr
+//===----------------------------------------------------------------------===//
+def DataLayoutSpecTrait
+    : NativeAttrTrait<"DataLayoutSpecInterface::Trait"> {
+  let cppNamespace = "::mlir";
+}
+
+def DLTI_DataLayoutSpecAttr :
+    DLTIAttr<"DataLayoutSpec", [DataLayoutSpecTrait]> {
+  let summary = [{
+    An attribute to represent a data layout specification.
+  }];
+  let description = [{
+    A data layout specification is a list of entries that specify (partial) data
+    layout information. It is expected to be attached to operations that serve
+    as scopes for data layout requests.
+  }];
+  let parameters = (ins
+    ArrayRefParameter<"DataLayoutEntryInterface", "">:$entries
+  );
+  let mnemonic = "dl_spec";
+  let genVerifyDecl = 1;
+  let hasCustomAssemblyFormat = 1;
+  let extraClassDeclaration = [{
+    /// Combines this specification with `specs`, enclosing specifications listed
+    /// from outermost to innermost. This overwrites the older entries with the
+    /// same key as the newer entries if the entries are compatible. Returns null
+    /// if the specifications are not compatible.
+    DataLayoutSpecAttr combineWith(ArrayRef<DataLayoutSpecInterface> specs) const;
+  
+    /// Returns the endiannes identifier.
+    StringAttr getEndiannessIdentifier(MLIRContext *context) const;
+
+    /// Returns the alloca memory space identifier.
+    StringAttr getAllocaMemorySpaceIdentifier(MLIRContext *context) const;
+
+    /// Returns the program memory space identifier.
+    StringAttr getProgramMemorySpaceIdentifier(MLIRContext *context) const;
+
+    /// Returns the global memory space identifier.
+    StringAttr getGlobalMemorySpaceIdentifier(MLIRContext *context) const;
+
+    /// Returns the stack alignment identifier.
+    StringAttr getStackAlignmentIdentifier(MLIRContext *context) const;
+  }];
+}
+
+//===----------------------------------------------------------------------===//
+// TargetSystemSpecAttr
+//===----------------------------------------------------------------------===//
+
+def TargetSystemSpecTrait
+    : NativeAttrTrait<"TargetSystemSpecInterface::Trait"> {
+  let cppNamespace = "::mlir";
+}
+
+def DLTI_TargetSystemSpecAttr :
+    DLTIAttr<"TargetSystemSpec", [TargetSystemSpecTrait]> {
+  let summary = [{
+    An attribute to represent target system specification.
+  }];
+  let description = [{
+    A system specification describes the overall system containing
+    multiple devices, with each device having a unique ID (string)
+    and its corresponding TargetDeviceSpec object.
+
+    Example:
+          dlti.target_system_spec =
+           #dlti.target_system_spec<
+            "CPU": #dlti.target_device_spec<
+                    #dlti.dl_entry<"dlti.L1_cache_size_in_bytes", 4096: ui32>>,
+            "GPU": #dlti.target_device_spec<
+                    #dlti.dl_entry<"dlti.max_vector_op_width", 64 : ui32>>,
+            "XPU": #dlti.target_device_spec<
+                    #dlti.dl_entry<"dlti.max_vector_op_width", 4096 : ui32>>>
+  }];
+  let parameters = (ins
+    ArrayRefParameter<"DeviceIDTargetDeviceSpecPair", "">:$entries
+  );
+  let mnemonic = "target_system_spec";
+  let genVerifyDecl = 1;
+  let assemblyFormat = "`<` $entries `>`";
+  let extraClassDeclaration = [{
+    /// Return the device specification that matches the given device ID
+    std::optional<TargetDeviceSpecInterface>
+    getDeviceSpecForDeviceID(
+      TargetSystemSpecInterface::DeviceID deviceID);
+  }];
+  let extraClassDefinition = [{
+    std::optional<TargetDeviceSpecInterface>
+    $cppClass::getDeviceSpecForDeviceID(
+        TargetSystemSpecInterface::DeviceID deviceID) {
+      for (const auto& entry : getEntries()) {
+        if (entry.first == deviceID)
+          return entry.second;
+      }
+      return std::nullopt;
+    }
+  }];
+}
+
+//===----------------------------------------------------------------------===//
+// TargetDeviceSpecAttr
+//===----------------------------------------------------------------------===//
+
+def TargetDeviceSpecTrait
+    : NativeAttrTrait<"TargetDeviceSpecInterface::Trait"> {
+  let cppNamespace = "::mlir";
+}
+
+def DLTI_TargetDeviceSpecAttr :
+    DLTIAttr<"TargetDeviceSpec", [TargetDeviceSpecTrait]> {
+  let summary = [{
+    An attribute to represent target device specification.
+  }];
+  let description = [{
+    Each device specification describes a single device and its
+    hardware properties. Each device specification can contain any number
+    of optional hardware properties (e.g., max_vector_op_width below).
+
+    Example:
+      #dlti.target_device_spec<
+        #dlti.dl_entry<"dlti.max_vector_op_width", 64 : ui32>>
+  }];
+  let parameters = (ins
+    ArrayRefParameter<"DataLayoutEntryInterface", "">:$entries
+  );
+  let mnemonic = "target_device_spec";
+  let genVerifyDecl = 1;
+  let assemblyFormat = "`<` $entries `>`";
+  let extraClassDeclaration = [{
+    /// Returns max vector op width identifier.
+    StringAttr getMaxVectorOpWidthIdentifier();
+
+    /// Returns L1 cache size identifier
+    StringAttr getL1CacheSizeInBytesIdentifier();
+
+    /// Returns the interface spec for max vector op width
+    /// Since max vector op width is an optional property, this function will
+    /// return a valid spec if the property is defined, otherwise it
+    /// will return an empty spec.
+    DataLayoutEntryInterface getSpecForMaxVectorOpWidth();
+
+    /// Returns the interface spec for L1 cache size
+    /// Since L1 cache size is an optional property, this function will
+    /// return a valid spec if the property is defined, otherwise it
+    /// will return an empty spec.
+    DataLayoutEntryInterface getSpecForL1CacheSizeInBytes();
----------------
nhasabni wrote:

Removed these APIs now.

https://github.com/llvm/llvm-project/pull/92138