Add support for module named metadata

This is mainly useful to get access to top-level debug information through 'llvm.dbg.cu'.

Wraps LLVM C-API functions `LLVMGetNamedMetadataNumOperands`, `LLVMGetNamedMetadataOperands` and `LLVMAddNamedMetadataOperand`.

Also add testcase.

llvm/_core.cpp

@@ -607,6 +607,27 @@ _wrap_obj2none(LLVMDeleteBasicBlock, LLVMBasicBlockRef)
 /*===-- MetaData -----------------------------------------------------===*/
 
 _wrap_objlist2obj(LLVMMetaDataGet, LLVMModuleRef, LLVMValueRef, LLVMValueRef)
+_wrap_objstrobj2none(LLVMAddNamedMetadataOperand, LLVMModuleRef, LLVMValueRef)
+
+static PyObject *
+_wLLVMGetNamedMetadataOperands(PyObject *self, PyObject *args)
+{
+    PyObject *obj_module;
+    const char *name;
+
+    if (!PyArg_ParseTuple(args, "Os", &obj_module, &name))
+        return NULL;
+
+    LLVMModuleRef module = (LLVMModuleRef)PyCapsule_GetPointer(obj_module, NULL);
+    unsigned num_operands = LLVMGetNamedMetadataNumOperands(module, name);
+    LLVMValueRef *operands = (LLVMValueRef*)malloc(sizeof(LLVMValueRef)*num_operands);
+    LLVMGetNamedMetadataOperands(module, name, operands);
+
+    PyObject *list = make_list_from_LLVMValueRef_array(operands, num_operands);
+    free(operands);
+
+    return list;
+}
 
 /*===-- Instructions -----------------------------------------------------===*/
 
@@ -1660,6 +1681,8 @@ static PyMethodDef core_methods[] = {
 
     /* MetaData */
     _method( LLVMMetaDataGet )
+    _method( LLVMGetNamedMetadataOperands )
+    _method( LLVMAddNamedMetadataOperand )
 
     /* Instructions */
     _method( LLVMGetInstructionParent )

llvm/core.py

@@ -1457,6 +1457,15 @@ class MetaData(Value):
         ptr = _core.LLVMMetaDataGet(module.ptr, vs)
         return MetaData(ptr)
 
+    @staticmethod
+    def get_named_operands(module, name):
+        lst = _core.LLVMGetNamedMetadataOperands(module.ptr, name)
+        return [MetaData(ptr) for ptr in lst]
+
+    @staticmethod
+    def add_named_operand(module, name, operand):
+        _core.LLVMAddNamedMetadataOperand(module.ptr, name, operand.ptr)
+
 #===----------------------------------------------------------------------===
 # Instruction
 #===----------------------------------------------------------------------===

llvm/test_llvmpy.py

@@ -16,7 +16,7 @@ else:
 
 from llvm import __version__
 from llvm.core import (Module, Type, GlobalVariable, Function, Builder,
-                       Constant)
+                       Constant, MetaData)
 import llvm.passes as lp
 import llvm.ee as le
 
@@ -390,6 +390,19 @@ tests.append(TestUses)
 
 # ---------------------------------------------------------------------------
 
+class TestMetaData(unittest.TestCase):
+    # test module metadata
+    def test_metadata(self):
+        m = Module.new('a')
+        metadata = MetaData.get(m, []) # empty metadata node
+        MetaData.add_named_operand(m, 'foo', metadata)
+        self.assertEqual(MetaData.get_named_operands(m, 'foo'), [metadata])
+        self.assertEqual(MetaData.get_named_operands(m, 'bar'), [])
+
+tests.append(TestMetaData)
+
+# ---------------------------------------------------------------------------
+
 def run(verbosity=1):
     print('llvmpy is installed in: ' + os.path.dirname(__file__))
     print('llvmpy version: ' + __version__)