[MLIR][Python] add GetTypeID for llvm.struct_type and llvm.ptr and enable downcasting (llvm#169383)

Author: makslevental

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);
 
@@ -58,6 +60,8 @@ 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(void);
+
 /// Returns `true` if the type is a literal (unnamed) LLVM struct type.
 MLIR_CAPI_EXPORTED bool mlirLLVMStructTypeIsLiteral(MlirType type);
 

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(
@@ -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,

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));
 }
@@ -73,6 +77,10 @@ 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();
 }

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
@@ -120,6 +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