[mlir][tosa] Add scaffolding for bytecode version. (#67374)

This does not decide on any specific bytecode version or structure, but
adds the scaffolding to make it easy to add.

Author: jpienaar

mlir/include/mlir/Dialect/Tosa/IR/CMakeLists.txt

@@ -6,3 +6,8 @@ set(LLVM_TARGET_DEFINITIONS TosaOps.td)
 mlir_tablegen(TosaAttributes.h.inc -gen-attrdef-decls)
 mlir_tablegen(TosaAttributes.cpp.inc -gen-attrdef-defs)
 add_public_tablegen_target(MLIRTosaAttributesIncGen)
+
+set(LLVM_TARGET_DEFINITIONS TosaDialectBytecode.td)
+mlir_tablegen(TosaDialectBytecode.cpp.inc -gen-bytecode -bytecode-dialect="Tosa")
+add_public_tablegen_target(MLIRTosaDialectBytecodeIncGen)
+

mlir/include/mlir/Dialect/Tosa/IR/TosaDialectBytecode.td

@@ -0,0 +1,28 @@
+//===-- TosaBytecode.td - Tosa bytecode defs -------------*- 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 is the TOSA bytecode reader/writer definition file.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef TOSA_DIALECT_BYTECODE
+#define TOSA_DIALECT_BYTECODE
+
+include "mlir/IR/BytecodeBase.td"
+
+/// This enum contains marker codes used to indicate which attribute is
+/// currently being decoded, and how it should be decoded. The order of these
+/// codes should generally be unchanged, as any changes will inevitably break
+/// compatibility with older bytecode.
+
+def TosaDialectTypes : DialectTypes<"Tosa"> {
+  let elems = [];
+}
+
+#endif // TOSA_DIALECT_BYTECODE
+

mlir/lib/Dialect/Tosa/CMakeLists.txt

@@ -9,6 +9,7 @@ add_mlir_dialect_library(MLIRTosaDialect
 
   DEPENDS
   MLIRTosaAttributesIncGen
+  MLIRTosaDialectBytecodeIncGen
   MLIRTosaOpsIncGen
   MLIRTosaInterfacesIncGen
 

mlir/lib/Dialect/Tosa/IR/TosaOps.cpp

@@ -39,6 +39,8 @@ using namespace mlir::tosa;
 #include "mlir/Dialect/Tosa/IR/TosaInterfaces.cpp.inc"
 
 namespace {
+#include "mlir/Dialect/Tosa/IR/TosaDialectBytecode.cpp.inc"
+
 //===----------------------------------------------------------------------===//
 // Dialect Function Inliner Interface.
 //===----------------------------------------------------------------------===//
@@ -62,6 +64,53 @@ struct TosaInlinerInterface : public DialectInlinerInterface {
             isa<tosa::WhileOp>(dest->getParentOp()));
   }
 };
+
+/// This class implements the bytecode interface for the Tosa dialect.
+struct TosaDialectBytecodeInterface : public BytecodeDialectInterface {
+  TosaDialectBytecodeInterface(Dialect *dialect)
+      : BytecodeDialectInterface(dialect) {}
+
+  //===--------------------------------------------------------------------===//
+  // Attributes
+
+  Attribute readAttribute(DialectBytecodeReader &reader) const override {
+    return ::readAttribute(getContext(), reader);
+  }
+
+  LogicalResult writeAttribute(Attribute attr,
+                               DialectBytecodeWriter &writer) const override {
+    return ::writeAttribute(attr, writer);
+  }
+
+  //===--------------------------------------------------------------------===//
+  // Types
+
+  Type readType(DialectBytecodeReader &reader) const override {
+    return ::readType(getContext(), reader);
+  }
+
+  LogicalResult writeType(Type type,
+                          DialectBytecodeWriter &writer) const override {
+    return ::writeType(type, writer);
+  }
+
+  void writeVersion(DialectBytecodeWriter &writer) const final {
+    // TODO: Populate.
+  }
+
+  std::unique_ptr<DialectVersion>
+  readVersion(DialectBytecodeReader &reader) const final {
+    // TODO: Populate
+    reader.emitError("Dialect does not support versioning");
+    return nullptr;
+  }
+
+  LogicalResult upgradeFromVersion(Operation *topLevelOp,
+                                   const DialectVersion &version_) const final {
+    return success();
+  }
+};
+
 } // namespace
 
 //===----------------------------------------------------------------------===//
@@ -84,7 +133,7 @@ void TosaDialect::initialize() {
 #define GET_ATTRDEF_LIST
 #include "mlir/Dialect/Tosa/IR/TosaAttributes.cpp.inc"
       >();
-  addInterfaces<TosaInlinerInterface>();
+  addInterfaces<TosaDialectBytecodeInterface, TosaInlinerInterface>();
 }
 
 Operation *TosaDialect::materializeConstant(OpBuilder &builder, Attribute value,

utils/bazel/llvm-project-overlay/mlir/BUILD.bazel

@@ -10612,6 +10612,25 @@ gentbl_cc_library(
     deps = [":TosaDialectTdFiles"],
 )
 
+gentbl_cc_library(
+    name = "TosaDialectBytecodeGen",
+    strip_include_prefix = "include",
+    tbl_outs = [
+        (
+            [
+                "-gen-bytecode",
+                "-bytecode-dialect=Tosa",
+            ],
+            "include/mlir/Dialect/Tosa/IR/TosaDialectBytecode.cpp.inc",
+        ),
+    ],
+    tblgen = ":mlir-tblgen",
+    td_file = "include/mlir/Dialect/Tosa/IR/TosaDialectBytecode.td",
+    deps = [
+        ":BytecodeTdFiles",
+    ],
+)
+
 gentbl_cc_library(
     name = "TosaInterfacesIncGen",
     tbl_outs = [
@@ -10689,6 +10708,7 @@ cc_library(
         ":QuantOps",
         ":Support",
         ":TensorDialect",
+        ":TosaDialectBytecodeGen",
         ":TosaDialectIncGen",
         ":TosaInterfacesIncGen",
         ":TosaPassIncGen",