From 592f9c698819e9efacd7d340eb27a03fd887770f Mon Sep 17 00:00:00 2001
From: Siu Kwan Lam <michael.lam.sk@gmail.com>
Date: Thu, 16 May 2013 13:45:59 -0500
Subject: [PATCH] Allow retrieving argument attributes

---
 llvm/core.py           | 38 ++++++++++++++++++++++++++++++++++++++
 llvm/test_llvmpy.py    | 18 ++++++++++++++++++
 llvmpy/src/Argument.py | 10 ++++++++++
 3 files changed, 66 insertions(+)

diff --git a/llvm/core.py b/llvm/core.py
index d25dec1..74d7101 100644
--- a/llvm/core.py
+++ b/llvm/core.py
@@ -1372,6 +1372,8 @@ class GlobalVariable(GlobalValue):
 
 class Argument(Value):
     _type_ = api.llvm.Argument
+    _valid_attrs = frozenset([ATTR_BY_VAL, ATTR_NEST, ATTR_NO_ALIAS,
+                              ATTR_NO_CAPTURE, ATTR_STRUCT_RET])
 
     def add_attribute(self, attr):
         context = api.llvm.getGlobalContext()
@@ -1379,6 +1381,9 @@ class Argument(Value):
         attrbldr.addAttribute(attr)
         attrs = api.llvm.Attributes.get(context, attrbldr)
         self._ptr.addAttr(attrs)
+        if attr not in self:
+            raise ValueError("Attribute %s is not valid for arg %s" %
+                             (attr, self))
 
     def remove_attribute(self, attr):
         context = api.llvm.getGlobalContext()
@@ -1400,6 +1405,39 @@ class Argument(Value):
     alignment = property(_get_alignment,
                          _set_alignment)
 
+    def __contains__(self, attr):
+        if attr == ATTR_BY_VAL:
+            return self.has_by_val()
+        elif attr == ATTR_NEST:
+            return self.has_nest()
+        elif attr == ATTR_NO_ALIAS:
+            return self.has_no_alias()
+        elif attr == ATTR_NO_CAPTURE:
+            return self.has_no_capture()
+        elif attr == ATTR_STRUCT_RET:
+            return self.has_struct_ret()
+        else:
+            raise ValueError('invalid attribute for argument')
+
+    @property
+    def arg_no(self):
+        return self._ptr.getArgNo()
+
+    def has_by_val(self):
+        return self._ptr.hasByValAttr()
+
+    def has_nest(self):
+        return self._ptr.hasNestAttr()
+
+    def has_no_alias(self):
+        return self._ptr.hasNoAliasAttr()
+
+    def has_no_capture(self):
+        return self._ptr.hasNoCaptureAttr()
+
+    def has_struct_ret(self):
+        return self._ptr.hasStructRetAttr()
+
 class Function(GlobalValue):
     _type_ = api.llvm.Function
 
diff --git a/llvm/test_llvmpy.py b/llvm/test_llvmpy.py
index 36ea022..3ecffff 100644
--- a/llvm/test_llvmpy.py
+++ b/llvm/test_llvmpy.py
@@ -1283,6 +1283,24 @@ class TestTypeHash(TestCase):
 
 tests.append(TestTypeHash)
 
+# ---------------------------------------------------------------------------
+
+class TestArgAttr(TestCase):
+    def test_arg_attr(self):
+        m = Module.new('oifjda')
+        vptr = Type.pointer(Type.float())
+        sptr = Type.pointer(Type.struct([]))
+        fnty = Type.function(Type.void(), [vptr] * 5)
+        func = m.add_function(fnty, 'foo')
+        attrs = [lc.ATTR_STRUCT_RET, lc.ATTR_BY_VAL, lc.ATTR_NEST,
+                 lc.ATTR_NO_ALIAS, lc.ATTR_NO_CAPTURE]
+        for i, attr in enumerate(attrs):
+            arg = func.args[i]
+            self.assertEqual(i, arg.arg_no)
+            arg.add_attribute(attr)
+            self.assertTrue(attr in func.args[i])
+
+tests.append(TestArgAttr)
 
 # ---------------------------------------------------------------------------
 
diff --git a/llvmpy/src/Argument.py b/llvmpy/src/Argument.py
index babbd1c..6262147 100644
--- a/llvmpy/src/Argument.py
+++ b/llvmpy/src/Argument.py
@@ -13,3 +13,13 @@ class Argument:
     removeAttr = Method(Void, ref(Attributes))
     getParamAlignment = Method(cast(Unsigned, int))
 
+    getArgNo = Method(cast(Unsigned, int))
+
+    hasByValAttr = Method(cast(Bool, bool))
+    hasNestAttr = Method(cast(Bool, bool))
+    hasNoAliasAttr = Method(cast(Bool, bool))
+    hasNoCaptureAttr = Method(cast(Bool, bool))
+    hasStructRetAttr = Method(cast(Bool, bool))
+
+    if LLVM_VERSION > (3, 2):
+        hasReturnedAttr = Method(cast(Bool, bool))