From c94e852c0e19de2a61bed4970f236a9e8e34d16a Mon Sep 17 00:00:00 2001
From: "Wladimir J. van der Laan" <laanwj@gmail.com>
Date: Fri, 14 Sep 2012 16:59:30 +0200
Subject: [PATCH] MetaData operands can be None. Handle this.

---
 llvm/_util.py       | 5 +++++
 llvm/core.py        | 9 +++++++--
 llvm/test_llvmpy.py | 6 ++++--
 3 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/llvm/_util.py b/llvm/_util.py
index 1766d6f..8f06122 100644
--- a/llvm/_util.py
+++ b/llvm/_util.py
@@ -62,6 +62,11 @@ def unpack_gen(objlist, check_fn):
     for obj in objlist: check_fn(obj)
     return [ obj.ptr for obj in objlist ]
 
+def unpack_gen_allow_none(objlist, check_fn):
+    for obj in objlist:
+        if obj is not None:
+            check_fn(obj)
+    return [ (obj.ptr if obj is not None else None) for obj in objlist ]
 
 #===----------------------------------------------------------------------===
 # Helper to wrap over iterables (LLVMFirstXXX, LLVMNextXXX). This used
diff --git a/llvm/core.py b/llvm/core.py
index a9c707e..52c9d7f 100644
--- a/llvm/core.py
+++ b/llvm/core.py
@@ -296,6 +296,9 @@ def unpack_types(objlst):     return _util.unpack_gen(objlst, check_is_type)
 def unpack_values(objlst):    return _util.unpack_gen(objlst, check_is_value)
 def unpack_constants(objlst): return _util.unpack_gen(objlst, check_is_constant)
 
+def unpack_values_or_none(objlst):
+    return _util.unpack_gen_allow_none(objlst, check_is_value)
+
 def check_is_callable(obj):
     if isinstance(obj, Function):
         return
@@ -1453,7 +1456,7 @@ class Function(GlobalValue):
 class MetaData(Value):
     @staticmethod
     def get(module, values):
-        vs = unpack_values(values)
+        vs = unpack_values_or_none(values)
         ptr = _core.LLVMMetaDataGet(module.ptr, vs)
         return MetaData(ptr)
 
@@ -1476,7 +1479,9 @@ class MetaData(Value):
         return [self._get_operand(i) for i in range(self.operand_count)]
 
     def _get_operand(self, i):
-        return _make_value(_core.LLVMMetaDataGetOperand(self.ptr, i))
+        val = _core.LLVMMetaDataGetOperand(self.ptr, i)
+        if val: # metadata operands can be None
+            return _make_value(val)
 
 class MetaDataString(Value):
     @staticmethod
diff --git a/llvm/test_llvmpy.py b/llvm/test_llvmpy.py
index 480aec4..6011a70 100644
--- a/llvm/test_llvmpy.py
+++ b/llvm/test_llvmpy.py
@@ -558,13 +558,15 @@ class TestMetaData(unittest.TestCase):
         m = Module.new('a')
         t = Type.int()
         metadata = MetaData.get(m, [Constant.int(t, 100),
-                                    MetaDataString.get(m, 'abcdef')])
+                                    MetaDataString.get(m, 'abcdef'),
+                                    None])
         MetaData.add_named_operand(m, 'foo', metadata)
         self.assertEqual(MetaData.get_named_operands(m, 'foo'), [metadata])
         self.assertEqual(MetaData.get_named_operands(m, 'bar'), [])
-        self.assertEqual(len(metadata.operands), 2)
+        self.assertEqual(len(metadata.operands), 3)
         self.assertEqual(metadata.operands[0].z_ext_value, 100)
         self.assertEqual(metadata.operands[1].string, 'abcdef')
+        self.assertTrue(metadata.operands[2] is None)
 
 tests.append(TestMetaData)