[Mlir-commits] [mlir] [MLIR][LLVM] Add bytecode support for several attributes (PR #162577)

[Bruno Cardoso Lopes]

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@@ -0,0 +1,357 @@
+//===-- LLVMDialectBytecode.td - LLVM 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 LLVM bytecode reader/writer definition file.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_DIALECT_BYTECODE
+#define LLVM_DIALECT_BYTECODE
+
+include "mlir/IR/BytecodeBase.td"
+
+//===----------------------------------------------------------------------===//
+// Bytecode classes for attributes and types.
+//===----------------------------------------------------------------------===//
+
+def String :
+  WithParser <"succeeded($_reader.readString($_var))",
+  WithBuilder<"$_args",
+  WithPrinter<"$_writer.writeOwnedString($_getter)",
+  WithType   <"StringRef">>>>;
+
+class Attr<string type> : WithType<type, Attribute>;
+
+class OptionalAttribute<string type> :
+  WithParser <"succeeded($_reader.readOptionalAttribute($_var))",
+  WithPrinter<"$_writer.writeOptionalAttribute($_getter)",
+  WithType<type, Attribute>>>;
+
+class OptionalInt<string type> :
+  WithParser <"succeeded(readOptionalInt($_reader, $_var))",
+  WithPrinter<"writeOptionalInt($_writer, $_getter)",
+  WithType<"std::optional<" # type # ">", VarInt>>>;
+
+class OptionalArrayRef<string eltType> :
+  WithParser <"succeeded(readOptionalArrayRef<"
+    # eltType # ">($_reader, $_var))",
+  WithPrinter<"writeOptionalArrayRef<"
+    # eltType # ">($_writer, $_getter)",
+  WithType<"SmallVector<"
+    # eltType # ">", Attribute>>>;
+
+class EnumClassFlag<string flag, string getter> :
+    WithParser<"succeeded($_reader.readVarInt($_var))",
+    WithBuilder<"(" # flag # ")$_args",
+    WithPrinter<"$_writer.writeVarInt((uint64_t)$_name." # getter # ")",
+    WithType<"uint64_t", VarInt>>>>;
+
+//===----------------------------------------------------------------------===//
+// General notes
+// - For each attribute or type entry, the argument names should match
+//   LLVMAttrDefs.td
+// - The mnemonics are either LLVM or builtin MLIR attributes and types, but
+//   regular C++ types are also allowed to match builders and parsers.
+//===----------------------------------------------------------------------===//
+
+//===----------------------------------------------------------------------===//
+// AliasScopeAttr
+//===----------------------------------------------------------------------===//
+
+def AliasScopeAttr : DialectAttribute<(attr
+  Attr<"Attribute">:$id,
+  Attr<"AliasScopeDomainAttr">:$domain,
+  OptionalAttribute<"StringAttr">:$description
+)>;
+
+//===----------------------------------------------------------------------===//
+// DIBasicTypeAttr
+//===----------------------------------------------------------------------===//
+
+def DIBasicTypeAttr : DialectAttribute<(attr
+  VarInt:$tag,
+  String:$name,
+  VarInt:$sizeInBits,
+  VarInt:$encoding
+)>;
+
+//===----------------------------------------------------------------------===//
+// DIExpressionAttr, DIExpressionElemAttr
+//===----------------------------------------------------------------------===//
+
+def DIExpressionElemAttr : DialectAttribute<(attr
+  VarInt:$opcode,
+  OptionalArrayRef<"uint64_t">:$arguments
+)>;
+
+def DIExpressionAttr : DialectAttribute<(attr
+  OptionalArrayRef<"DIExpressionElemAttr">:$operations
+)>;
+
+//===----------------------------------------------------------------------===//
+// DIFileAttr
+//===----------------------------------------------------------------------===//
+
+def DIFileAttr : DialectAttribute<(attr
+  String:$name,
+  String:$directory
+)>;
+
+//===----------------------------------------------------------------------===//
+// DILocalVariableAttr
+//===----------------------------------------------------------------------===//
+
+def DILocalVariableAttr : DialectAttribute<(attr
+  Attr<"DIScopeAttr">:$scope, // Non-optional attribute
+  OptionalAttribute<"StringAttr">:$name,
+  OptionalAttribute<"DIFileAttr">:$file,
+  VarInt:$line,
+  VarInt:$arg,
+  VarInt:$alignInBits,
+  OptionalAttribute<"DITypeAttr">:$type,
+  EnumClassFlag<"DIFlags", "getFlags()">:$_rawflags,
+  LocalVar<"DIFlags", "(DIFlags)_rawflags">:$flags
----------------
bcardosolopes wrote:

Yes, inspired by bytecode support in other dialects, far from pretty tho =(

Possible future work is to improve tablegen emitter to maybe do more about these, but AFAIK we can't do better right now with tablegen - one possibility is to write plain C++ for these attributes, but that doesn't sounds like much win either.

https://github.com/llvm/llvm-project/pull/162577