[PATCH v8 5/6] test_bits: add tests for GENMASK_U*()

[Vincent Mailhol via B4 Relay]

From: Lucas De Marchi <lucas.demarchi@xxxxxxxxx>

Add some additional tests in lib/tests/test_bits.c to cover the
expected/non-expected values of the fixed-type GENMASK_U*() macros.

Also check that the result value matches the expected type. Since
those are known at build time, use static_assert() instead of normal
kunit tests.

Signed-off-by: Lucas De Marchi <lucas.demarchi@xxxxxxxxx>
Signed-off-by: Vincent Mailhol <mailhol.vincent@xxxxxxxxxx>
---
Changelog:

  v7 -> v8:

    - In commit db6fe4d61ece ("lib: Move KUnit tests into tests/
      subdirectory"), lib/test_bits.c was moved to
      lib/tests/test_bits.c. Adjust the patch descrption accordingly.

  v6 -> v7:
  v5 -> v6:

    - No changes.

  v4 -> v5:

    - Revert v4 change. GENMASK_U8()/GENMASK_U16() are now back to
      u8/u16.

  v3 -> v4:

    - Adjust the type of GENMASK_U8()/GENMASK_U16() from u8/u16 to
      unsigned int.

    - Reorder the tests to match the order in which the macros are
      declared in bits.h.
---
 lib/tests/test_bits.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/lib/tests/test_bits.c b/lib/tests/test_bits.c
index c7b38d91e1f16d42b7ca92e62fbd6c19b37e76a0..f443476f3265c463c1219b13c1ef9663d238d58b 100644
--- a/lib/tests/test_bits.c
+++ b/lib/tests/test_bits.c
@@ -5,6 +5,16 @@
 
 #include <kunit/test.h>
 #include <linux/bits.h>
+#include <linux/types.h>
+
+#define assert_type(t, x) _Generic(x, t: x, default: 0)
+
+static_assert(assert_type(unsigned long, GENMASK(31, 0)) == U32_MAX);
+static_assert(assert_type(unsigned long long, GENMASK_ULL(63, 0)) == U64_MAX);
+static_assert(assert_type(u8, GENMASK_U8(7, 0)) == U8_MAX);
+static_assert(assert_type(u16, GENMASK_U16(15, 0)) == U16_MAX);
+static_assert(assert_type(u32, GENMASK_U32(31, 0)) == U32_MAX);
+static_assert(assert_type(u64, GENMASK_U64(63, 0)) == U64_MAX);
 
 
 static void genmask_test(struct kunit *test)
@@ -14,11 +24,21 @@ static void genmask_test(struct kunit *test)
 	KUNIT_EXPECT_EQ(test, 6ul, GENMASK(2, 1));
 	KUNIT_EXPECT_EQ(test, 0xFFFFFFFFul, GENMASK(31, 0));
 
+	KUNIT_EXPECT_EQ(test, 1u, GENMASK_U8(0, 0));
+	KUNIT_EXPECT_EQ(test, 3u, GENMASK_U16(1, 0));
+	KUNIT_EXPECT_EQ(test, 0x10000, GENMASK_U32(16, 16));
+
 #ifdef TEST_GENMASK_FAILURES
 	/* these should fail compilation */
 	GENMASK(0, 1);
 	GENMASK(0, 10);
 	GENMASK(9, 10);
+
+	GENMASK_U32(0, 31);
+	GENMASK_U64(64, 0);
+	GENMASK_U32(32, 0);
+	GENMASK_U16(16, 0);
+	GENMASK_U8(8, 0);
 #endif
 
 

-- 
2.48.1