Add script to debug fixed point numbers in lldb

2026-09-20 13:35:43 +02:00
parent 15f07edaaf
commit bcf1e114ef
4 changed files with 195 additions and 10 deletions
@@ -0,0 +1,58 @@
+import unittest
+
+import lldb_fixed
+
+
+class ParseFixedTypeTests(unittest.TestCase):
+    def test_direct_typenum_alias(self):
+        self.assertEqual(
+            lldb_fixed.parse_fixed_type("fixed::FixedI32<typenum::uint::U16>"),
+            (True, 32, 16),
+        )
+
+    def test_expanded_typenum(self):
+        type_name = (
+            "fixed::FixedI32<"
+            "typenum::uint::UInt<"
+            "typenum::uint::UInt<"
+            "typenum::uint::UInt<"
+            "typenum::uint::UInt<"
+            "typenum::uint::UInt<typenum::uint::UTerm, typenum::bit::B1>, "
+            "typenum::bit::B0>, typenum::bit::B0>, typenum::bit::B0>, "
+            "typenum::bit::B0>>"
+        )
+        self.assertEqual(lldb_fixed.parse_fixed_type(type_name), (True, 32, 16))
+
+    def test_unsigned_type(self):
+        self.assertEqual(
+            lldb_fixed.parse_fixed_type("fixed::FixedU64<typenum::uint::U24>"),
+            (False, 64, 24),
+        )
+
+    def test_unrelated_type(self):
+        self.assertIsNone(lldb_fixed.parse_fixed_type("core::primitive::i32"))
+
+
+class FormatFixedTests(unittest.TestCase):
+    def test_q16_16(self):
+        self.assertEqual(lldb_fixed.format_fixed(3 << 15, 16), "1.5")
+        self.assertEqual(lldb_fixed.format_fixed(-(3 << 15), 16), "-1.5")
+        self.assertEqual(lldb_fixed.format_fixed(1, 16), "0.0000152587890625")
+
+    def test_integer_value_has_no_decimal_suffix(self):
+        self.assertEqual(lldb_fixed.format_fixed(12 << 16, 16), "12")
+
+    def test_q96_32(self):
+        raw = (1 << 100) + (1 << 31)
+        self.assertEqual(
+            lldb_fixed.format_fixed(raw, 32),
+            "295147905179352825856.5",
+        )
+
+    def test_twos_complement_normalization(self):
+        self.assertEqual(lldb_fixed.normalize_bits(0xFFFF8000, True, 32), -32768)
+        self.assertEqual(lldb_fixed.normalize_bits(0xFFFF8000, False, 32), 0xFFFF8000)
+
+
+if __name__ == "__main__":
+    unittest.main()