[Mlir-commits] [mlir] [MLIR][Python] add GetTypeID for llvm.struct_type and llvm.ptr and enable downcasting (PR #169383)

[Maksim Levental]

https://github.com/makslevental updated https://github.com/llvm/llvm-project/pull/169383

>From b8d0de73cb4e2073ec94bb8a672aecdbf00acadb Mon Sep 17 00:00:00 2001
From: Maksim Levental <maksim.levental at gmail.com>
Date: Mon, 24 Nov 2025 10:19:20 -0800
Subject: [PATCH 1/2] [MLIR][Python] add mlirLLVMStructTypeGetTypeID and enable
 downcasting for StructType

---
 mlir/include/mlir-c/Dialect/LLVM.h       | 2 ++
 mlir/lib/Bindings/Python/DialectLLVM.cpp | 4 ++--
 mlir/lib/CAPI/Dialect/LLVM.cpp           | 4 ++++
 mlir/test/python/dialects/llvm.py        | 3 +++
 4 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/mlir/include/mlir-c/Dialect/LLVM.h b/mlir/include/mlir-c/Dialect/LLVM.h
index c1ade9ed8617c..a0fbfd5c8227a 100644
--- a/mlir/include/mlir-c/Dialect/LLVM.h
+++ b/mlir/include/mlir-c/Dialect/LLVM.h
@@ -58,6 +58,8 @@ MLIR_CAPI_EXPORTED MlirType mlirLLVMFunctionTypeGetReturnType(MlirType type);
 /// Returns `true` if the type is an LLVM dialect struct type.
 MLIR_CAPI_EXPORTED bool mlirTypeIsALLVMStructType(MlirType type);
 
+MLIR_CAPI_EXPORTED MlirTypeID mlirLLVMStructTypeGetTypeID();
+
 /// Returns `true` if the type is a literal (unnamed) LLVM struct type.
 MLIR_CAPI_EXPORTED bool mlirLLVMStructTypeIsLiteral(MlirType type);
 
diff --git a/mlir/lib/Bindings/Python/DialectLLVM.cpp b/mlir/lib/Bindings/Python/DialectLLVM.cpp
index 870a713b8edcb..63aa707a4adde 100644
--- a/mlir/lib/Bindings/Python/DialectLLVM.cpp
+++ b/mlir/lib/Bindings/Python/DialectLLVM.cpp
@@ -31,8 +31,8 @@ static void populateDialectLLVMSubmodule(nanobind::module_ &m) {
   // StructType
   //===--------------------------------------------------------------------===//
 
-  auto llvmStructType =
-      mlir_type_subclass(m, "StructType", mlirTypeIsALLVMStructType);
+  auto llvmStructType = mlir_type_subclass(
+      m, "StructType", mlirTypeIsALLVMStructType, mlirLLVMStructTypeGetTypeID);
 
   llvmStructType
       .def_classmethod(
diff --git a/mlir/lib/CAPI/Dialect/LLVM.cpp b/mlir/lib/CAPI/Dialect/LLVM.cpp
index 6636f0ea73ec9..560148abf4c91 100644
--- a/mlir/lib/CAPI/Dialect/LLVM.cpp
+++ b/mlir/lib/CAPI/Dialect/LLVM.cpp
@@ -73,6 +73,10 @@ bool mlirTypeIsALLVMStructType(MlirType type) {
   return isa<LLVM::LLVMStructType>(unwrap(type));
 }
 
+MlirTypeID mlirLLVMStructTypeGetTypeID() {
+  return wrap(LLVM::LLVMStructType::getTypeID());
+}
+
 bool mlirLLVMStructTypeIsLiteral(MlirType type) {
   return !cast<LLVM::LLVMStructType>(unwrap(type)).isIdentified();
 }
diff --git a/mlir/test/python/dialects/llvm.py b/mlir/test/python/dialects/llvm.py
index 8ea0fddee3f7c..42543de851436 100644
--- a/mlir/test/python/dialects/llvm.py
+++ b/mlir/test/python/dialects/llvm.py
@@ -98,6 +98,9 @@ def testStructType():
     assert opaque.opaque
     # CHECK: !llvm.struct<"opaque", opaque>
 
+    typ = Type.parse('!llvm.struct<"zoo", (i32, i64)>')
+    assert isinstance(typ, llvm.StructType)
+
 
 # CHECK-LABEL: testSmoke
 @constructAndPrintInModule

>From 605dbe2f6ce444ec24af836f9dd59e4d49356dc6 Mon Sep 17 00:00:00 2001
From: Maksim Levental <maksim.levental at gmail.com>
Date: Mon, 24 Nov 2025 10:24:34 -0800
Subject: [PATCH 2/2] add pointer

---
 mlir/include/mlir-c/Dialect/LLVM.h       | 4 +++-
 mlir/lib/Bindings/Python/DialectLLVM.cpp | 3 ++-
 mlir/lib/CAPI/Dialect/LLVM.cpp           | 4 ++++
 mlir/test/python/dialects/llvm.py        | 3 +++
 4 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/mlir/include/mlir-c/Dialect/LLVM.h b/mlir/include/mlir-c/Dialect/LLVM.h
index a0fbfd5c8227a..cc7f09f71d028 100644
--- a/mlir/include/mlir-c/Dialect/LLVM.h
+++ b/mlir/include/mlir-c/Dialect/LLVM.h
@@ -23,6 +23,8 @@ MLIR_DECLARE_CAPI_DIALECT_REGISTRATION(LLVM, llvm);
 MLIR_CAPI_EXPORTED MlirType mlirLLVMPointerTypeGet(MlirContext ctx,
                                                    unsigned addressSpace);
 
+MLIR_CAPI_EXPORTED MlirTypeID mlirLLVMPointerTypeGetTypeID(void);
+
 /// Returns `true` if the type is an LLVM dialect pointer type.
 MLIR_CAPI_EXPORTED bool mlirTypeIsALLVMPointerType(MlirType type);
 
@@ -58,7 +60,7 @@ MLIR_CAPI_EXPORTED MlirType mlirLLVMFunctionTypeGetReturnType(MlirType type);
 /// Returns `true` if the type is an LLVM dialect struct type.
 MLIR_CAPI_EXPORTED bool mlirTypeIsALLVMStructType(MlirType type);
 
-MLIR_CAPI_EXPORTED MlirTypeID mlirLLVMStructTypeGetTypeID();
+MLIR_CAPI_EXPORTED MlirTypeID mlirLLVMStructTypeGetTypeID(void);
 
 /// Returns `true` if the type is a literal (unnamed) LLVM struct type.
 MLIR_CAPI_EXPORTED bool mlirLLVMStructTypeIsLiteral(MlirType type);
diff --git a/mlir/lib/Bindings/Python/DialectLLVM.cpp b/mlir/lib/Bindings/Python/DialectLLVM.cpp
index 63aa707a4adde..05681cecf82b3 100644
--- a/mlir/lib/Bindings/Python/DialectLLVM.cpp
+++ b/mlir/lib/Bindings/Python/DialectLLVM.cpp
@@ -137,7 +137,8 @@ static void populateDialectLLVMSubmodule(nanobind::module_ &m) {
   // PointerType
   //===--------------------------------------------------------------------===//
 
-  mlir_type_subclass(m, "PointerType", mlirTypeIsALLVMPointerType)
+  mlir_type_subclass(m, "PointerType", mlirTypeIsALLVMPointerType,
+                     mlirLLVMPointerTypeGetTypeID)
       .def_classmethod(
           "get",
           [](const nb::object &cls, std::optional<unsigned> addressSpace,
diff --git a/mlir/lib/CAPI/Dialect/LLVM.cpp b/mlir/lib/CAPI/Dialect/LLVM.cpp
index 560148abf4c91..bf231767320a5 100644
--- a/mlir/lib/CAPI/Dialect/LLVM.cpp
+++ b/mlir/lib/CAPI/Dialect/LLVM.cpp
@@ -27,6 +27,10 @@ MlirType mlirLLVMPointerTypeGet(MlirContext ctx, unsigned addressSpace) {
   return wrap(LLVMPointerType::get(unwrap(ctx), addressSpace));
 }
 
+MlirTypeID mlirLLVMPointerTypeGetTypeID() {
+  return wrap(LLVM::LLVMPointerType::getTypeID());
+}
+
 bool mlirTypeIsALLVMPointerType(MlirType type) {
   return isa<LLVM::LLVMPointerType>(unwrap(type));
 }
diff --git a/mlir/test/python/dialects/llvm.py b/mlir/test/python/dialects/llvm.py
index 42543de851436..305ed9aba940d 100644
--- a/mlir/test/python/dialects/llvm.py
+++ b/mlir/test/python/dialects/llvm.py
@@ -123,6 +123,9 @@ def testPointerType():
     # CHECK: !llvm.ptr<1>
     print(ptr_with_addr)
 
+    typ = Type.parse("!llvm.ptr<1>")
+    assert isinstance(typ, llvm.PointerType)
+
 
 # CHECK-LABEL: testConstant
 @constructAndPrintInModule