Revert "bit: Implement a branchless has_single_bit()"

Doesn't work for the highest bit due to overflow.

This reverts commit 208376ef99da243545efcd6fb02d3469b4c068ed.

2 files changed, 2 insertions, 2 deletions

diff --git a/src/bit.h b/src/bit.h
index e680fed..21a8076 100644
--- a/src/bit.h
+++ b/src/bit.h
@@ -350,8 +350,7 @@ UINT_OVERLOADS(FIRST_TRAILING_ONE)
 
 #define HAS_SINGLE_BIT(type, suffix, width) \
 	static inline bool has_single_bit##suffix(type n) { \
-		/** Branchless n && !(n & (n - 1)) */ \
-		return n < (n ^ (n - 1)) + 1; \
+		return n && !(n & (n - 1)); \
 	}
 
 UINT_OVERLOADS(ROTATE_LEFT)
diff --git a/tests/bit.c b/tests/bit.c
index 7b20770..f9071be 100644
--- a/tests/bit.c
+++ b/tests/bit.c
@@ -119,6 +119,7 @@ int main(void) {
 
 	bfs_verify(!has_single_bit(0));
 	bfs_verify(!has_single_bit(UINT32_MAX));
+	bfs_verify(has_single_bit((uint32_t)1 << (UINT_WIDTH - 1)));
 
 	return EXIT_SUCCESS;
 }