[lldb] Make sure that the "TypeSystemClang::GetBuiltinTypeByName" method returns the correct value also for "_BitInt(...)" types. (#165857)

When trying to get the `SBType` object corresponding to the
`_BitInt(...)` type name, we have noticed that the
`SBTarget::FindFirstType` metod returns `nil`. This branch proposes:
- some test that demonstrate that the problem exists
- a possible fix

---------

Co-authored-by: Matej Košík <matej.kosik@codasip.com>
Co-authored-by: Michael Buch <michaelbuch12@gmail.com>

1 files changed, 16 insertions, 0 deletions

diff --git a/lldb/test/API/python_api/sbtype_basic_type/TestSBTypeBasicType.py b/lldb/test/API/python_api/sbtype_basic_type/TestSBTypeBasicType.py
index f8594df..784f3e1 100644
--- a/lldb/test/API/python_api/sbtype_basic_type/TestSBTypeBasicType.py
+++ b/lldb/test/API/python_api/sbtype_basic_type/TestSBTypeBasicType.py
@@ -36,3 +36,19 @@ class TestCase(TestBase):
         # Check the size of the chosen aliases of basic types.
         self.assertEqual(self.target().FindFirstType("__int128_t").size, 16)
         self.assertEqual(self.target().FindFirstType("__uint128_t").size, 16)
+
+        self.assertFalse(self.target().FindFirstType("_BitInt"))
+        self.assertFalse(self.target().FindFirstType("unsigned _BitInt"))
+        self.assertFalse(self.target().FindFirstType("_BitInt()"))
+        self.assertFalse(self.target().FindFirstType("unsigned _BitInt()"))
+        self.assertFalse(self.target().FindFirstType("_BitInt(65"))
+        self.assertFalse(self.target().FindFirstType("unsigned _BitInt(65"))
+        self.assertFalse(self.target().FindFirstType("_BitInt(0x41)"))
+        self.assertFalse(self.target().FindFirstType("unsigned _BitInt(0x41)"))
+        self.assertEqual(self.target().FindFirstType("_BitInt(65)").name, "_BitInt(65)")
+        self.assertEqual(self.target().FindFirstType("_BitInt(65)").size, 16)
+        self.assertEqual(
+            self.target().FindFirstType("unsigned _BitInt(65)").name,
+            "unsigned _BitInt(65)",
+        )
+        self.assertEqual(self.target().FindFirstType("unsigned _BitInt(65)").size, 16)