Add optional type name override

Add llvmTypeNameOverride property to DialectType to allow overriding
the LLVM IR type name generated for dialect types. This is useful when
the natural dialect+mnemonic name does not match backend conventions.

Author: piotrAMD

include/llvm-dialects/Dialect/Dialect.td

@@ -239,6 +239,10 @@ class DialectType<Dialect dialect_, string mnemonic_> : Type, Predicate {
   ///    discriminant; the discriminant should be a type that cannot naturally
   ///    appear elsewhere, e.g. (repr_struct (IntegerType 41))
   dag representation = (repr_targetext);
+
+  /// Optional custom name for the LLVM IR type. If not set, defaults to
+  /// "<dialect>.<mnemonic>".
+  string llvmTypeNameOverride = "";
 }
 
 def and;

include/llvm-dialects/TableGen/DialectType.h

@@ -46,6 +46,9 @@ class DialectType : public BaseCppPredicate {
   RecordTy *getDialectRec() const { return m_dialectRec; }
   llvm::StringRef getName() const { return m_name; }
   llvm::StringRef getMnemonic() const { return m_mnemonic; }
+  llvm::StringRef getLlvmTypeNameOverride() const {
+    return m_llvmTypeNameOverride;
+  }
   bool defaultGetterHasExplicitContextArgument() const {
     return m_defaultGetterHasExplicitContextArgument;
   }
@@ -64,6 +67,7 @@ class DialectType : public BaseCppPredicate {
   RecordTy *m_dialectRec = nullptr;
   std::string m_name;
   std::string m_mnemonic;
+  std::string m_llvmTypeNameOverride;
   bool m_defaultGetterHasExplicitContextArgument = false;
   std::string m_summary;
   std::string m_description;

lib/TableGen/DialectType.cpp

@@ -43,6 +43,7 @@ bool DialectType::init(raw_ostream &errs, GenDialectsContext &context,
   m_mnemonic = record->getValueAsString("mnemonic");
   m_summary = record->getValueAsString("summary");
   m_description = record->getValueAsString("description");
+  m_llvmTypeNameOverride = record->getValueAsString("llvmTypeNameOverride");
 
   if (auto *dag =
           cast<DagInit>(record->getValue("representation")->getValue())) {
@@ -170,12 +171,25 @@ void DialectType::emitDeclaration(raw_ostream &out, GenDialect *dialect) const {
   fmt.addSubst("_type", getName());
   fmt.addSubst("mnemonic", getMnemonic());
 
+  std::string typeName;
+  if (!m_llvmTypeNameOverride.empty()) {
+    typeName = m_llvmTypeNameOverride;
+  } else {
+    typeName = (dialect->name + "." + getMnemonic()).str();
+  }
+  // For struct-backed types, add trailing dot for the prefix
+  if (m_structBacked) {
+    typeName += ".";
+  }
+
+  fmt.addSubst("typeName", typeName);
+
   if (m_structBacked) {
     out << tgfmt(R"(
     class $_type : public ::llvm::StructType {
       using ::llvm::StructType::StructType;
     public:
-      static constexpr ::llvm::StringLiteral s_prefix{"$dialect.$mnemonic."};
+      static constexpr ::llvm::StringLiteral s_prefix{"$typeName"};
 
       using ::llvm::StructType::getElementType;
 
@@ -225,10 +239,11 @@ void DialectType::emitDeclaration(raw_ostream &out, GenDialect *dialect) const {
   } else {
 
     // TargetExtType
+    fmt.addSubst("typeName", typeName);
 
     out << tgfmt(R"(
     class $_type : public ::llvm::TargetExtType {
-      static constexpr ::llvm::StringLiteral s_name{"$dialect.$mnemonic"};
+      static constexpr ::llvm::StringLiteral s_name{"$typeName"};
 
     public:
       static bool classof(const ::llvm::TargetExtType *t) {
@@ -276,6 +291,14 @@ void DialectType::emitDefinition(raw_ostream &out, GenDialect *dialect) const {
   fmt.addSubst("fields", symbols.chooseName("fields"));
   fmt.addSubst("st", symbols.chooseName("st"));
 
+  // Compute the type name prefix (without trailing dot for struct-backed types)
+  std::string typeNamePrefix;
+  if (!m_llvmTypeNameOverride.empty()) {
+    typeNamePrefix = m_llvmTypeNameOverride;
+  } else {
+    typeNamePrefix = (dialect->name + "." + getMnemonic()).str();
+  }
+
   if (m_structBacked) {
     out << tgfmt("$_type* $_type::get(", &fmt);
     bool contextPresent =
@@ -305,7 +328,7 @@ void DialectType::emitDefinition(raw_ostream &out, GenDialect *dialect) const {
 
     out << tgfmt(
         "  std::string $name; ::llvm::raw_string_ostream $os($name);\n", &fmt);
-    out << tgfmt("  $os << \"$0\";\n", &fmt, m_mnemonic);
+    out << tgfmt("  $os << \"$0\";\n", &fmt, typeNamePrefix);
     for (const auto &getterArg : getterArgs)
       out << tgfmt("  $os << '.' << (uint64_t)$0;\n", &fmt, getterArg.name);
 

test/example/generated/ExampleDialect.cpp.inc

@@ -263,7 +263,7 @@ StructBackedType* StructBackedType::get(::llvm::LLVMContext & ctx, uint32_t fiel
 
 static_assert(sizeof(field2) <= sizeof(unsigned));
   std::string name; ::llvm::raw_string_ostream os(name);
-  os << "struct.backed";
+  os << "xd.ir.struct.backed";
   os << '.' << (uint64_t)field0;
   os << '.' << (uint64_t)field1;
   os << '.' << (uint64_t)field2;

test/unit/dialect/TestDialect.td

@@ -82,3 +82,56 @@ def InstNameConflictWithExplRetTestOp : Op<TestDialect, "try.conflict.type.suffi
     value like IRBuilder methods. This op tries to produce a conflict
   }];
 }
+
+// Test types with custom llvmTypeNameOverride
+
+// Test TargetExtType with custom name
+def CustomNameTargetExtType : DialectType<TestDialect, "custom.target"> {
+  let typeArguments = (args
+    AttrI32:$param1,
+    AttrI32:$param2
+  );
+
+  let defaultGetterHasExplicitContextArgument = true;
+  let llvmTypeNameOverride = "custom.renamed.target";
+
+  let summary = "TargetExtType with custom name";
+  let description = [{
+    Tests that llvmTypeNameOverride works for TargetExtType.
+    Type name should be "custom.renamed.target" instead of "test.custom.target".
+  }];
+}
+
+// Test struct-backed type with custom name prefix
+def CustomNameStructType : DialectType<TestDialect, "custom.struct"> {
+  let typeArguments = (args
+    AttrI32:$rows,
+    AttrI32:$cols
+  );
+
+  let defaultGetterHasExplicitContextArgument = true;
+  let representation = (repr_struct (IntegerType 73));
+  let llvmTypeNameOverride = "custom.renamed.struct";
+
+  let summary = "Struct-backed type with custom name prefix";
+  let description = [{
+    Tests that llvmTypeNameOverride works for struct-backed types.
+    Type name prefix should be "custom.renamed.struct." instead of "test.custom.struct.".
+    The trailing dot is automatically added for struct types.
+  }];
+}
+
+// Test TargetExtType without custom name (default behavior)
+def DefaultNameTargetExtType : DialectType<TestDialect, "default.target"> {
+  let typeArguments = (args
+    AttrI32:$value
+  );
+
+  let defaultGetterHasExplicitContextArgument = true;
+
+  let summary = "TargetExtType with default name";
+  let description = [{
+    Tests default naming behavior for TargetExtType.
+    Type name should be "test.default.target".
+  }];
+}

test/unit/interface/CMakeLists.txt

@@ -20,6 +20,7 @@
 add_dialects_unit_test(DialectsADTTests
     OpSetTests.cpp
     OpMapTests.cpp
-    OpMapIRTests.cpp)
+    OpMapIRTests.cpp
+    DialectTypeTests.cpp)
 
 add_dependencies(DialectsADTTests TestDialectTableGen)

test/unit/interface/DialectTypeTests.cpp

@@ -0,0 +1,114 @@
+/*
+ ***********************************************************************************************************************
+ * Copyright (c) 2026 Advanced Micro Devices, Inc. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ ***********************************************************************************************************************
+ */
+
+#include "TestDialect.h"
+#include "llvm/IR/LLVMContext.h"
+#include "llvm/IR/Type.h"
+#include "gtest/gtest.h"
+
+using namespace llvm;
+using namespace test;
+
+// Test custom llvmTypeNameOverride for TargetExtType
+TEST(DialectTypeTest, CustomNameTargetExtType) {
+  LLVMContext ctx;
+
+  auto *type = CustomNameTargetExtType::get(ctx, 10, 20);
+  ASSERT_NE(type, nullptr);
+
+  // Verify it's recognized as the correct type via classof
+  EXPECT_TRUE(isa<CustomNameTargetExtType>(type));
+  EXPECT_TRUE(CustomNameTargetExtType::classof(type));
+
+  // Verify the type name is the custom one, not the default
+  auto *targetExtType = cast<TargetExtType>(type);
+  EXPECT_EQ(targetExtType->getName(), "custom.renamed.target");
+
+  // Verify parameters are accessible
+  EXPECT_EQ(type->getParam1(), 10u);
+  EXPECT_EQ(type->getParam2(), 20u);
+}
+
+// Test custom llvmTypeNameOverride for struct-backed type
+TEST(DialectTypeTest, CustomNameStructType) {
+  LLVMContext ctx;
+
+  auto *type = CustomNameStructType::get(ctx, 16, 16);
+  ASSERT_NE(type, nullptr);
+
+  // Verify it's recognized as the correct type via classof
+  EXPECT_TRUE(isa<CustomNameStructType>(type));
+  EXPECT_TRUE(CustomNameStructType::classof(type));
+
+  // Verify the struct type name has the custom prefix
+  auto *structType = cast<StructType>(type);
+  EXPECT_TRUE(structType->getName().starts_with("custom.renamed.struct."));
+
+  // Verify parameters are accessible
+  EXPECT_EQ(type->getRows(), 16u);
+  EXPECT_EQ(type->getCols(), 16u);
+}
+
+// Test default naming behavior (no llvmTypeNameOverride specified)
+TEST(DialectTypeTest, DefaultNameTargetExtType) {
+  LLVMContext ctx;
+
+  auto *type = DefaultNameTargetExtType::get(ctx, 42);
+  ASSERT_NE(type, nullptr);
+
+  // Verify it's recognized as the correct type
+  EXPECT_TRUE(isa<DefaultNameTargetExtType>(type));
+  EXPECT_TRUE(DefaultNameTargetExtType::classof(type));
+
+  // Verify the type name uses the default dialect.mnemonic format
+  auto *targetExtType = cast<TargetExtType>(type);
+  EXPECT_EQ(targetExtType->getName(), "test.default.target");
+
+  // Verify parameter is accessible
+  EXPECT_EQ(type->getValue(), 42u);
+}
+
+// Test that different custom types are distinguishable
+TEST(DialectTypeTest, TypeDistinction) {
+  LLVMContext ctx;
+
+  auto *customTarget = CustomNameTargetExtType::get(ctx, 1, 2);
+  auto *defaultTarget = DefaultNameTargetExtType::get(ctx, 3);
+  auto *customStruct = CustomNameStructType::get(ctx, 4, 5);
+
+  // Types should be distinct
+  EXPECT_NE(static_cast<llvm::Type *>(customTarget),
+            static_cast<llvm::Type *>(defaultTarget));
+  EXPECT_NE(static_cast<llvm::Type *>(customTarget),
+            static_cast<llvm::Type *>(customStruct));
+  EXPECT_NE(static_cast<llvm::Type *>(defaultTarget),
+            static_cast<llvm::Type *>(customStruct));
+
+  // classof should work correctly
+  EXPECT_TRUE(CustomNameTargetExtType::classof(customTarget));
+  EXPECT_FALSE(CustomNameTargetExtType::classof(defaultTarget));
+  EXPECT_FALSE(CustomNameTargetExtType::classof(customStruct));
+
+  EXPECT_FALSE(DefaultNameTargetExtType::classof(customTarget));
+  EXPECT_TRUE(DefaultNameTargetExtType::classof(defaultTarget));
+  EXPECT_FALSE(DefaultNameTargetExtType::classof(customStruct));
+
+  EXPECT_FALSE(CustomNameStructType::classof(customTarget));
+  EXPECT_FALSE(CustomNameStructType::classof(defaultTarget));
+  EXPECT_TRUE(CustomNameStructType::classof(customStruct));
+}