[libcxx-commits] [libcxx] [libc++] Don't bother asserting that <bit> functions get unsigned types (PR #161487)

[via libcxx-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-libcxx

Author: Nikolas Klauser (philnik777)

<details>
<summary>Changes</summary>

The builtins already diagnose types other than unsigned integers, so there is no point in `static_assert`ing that again.


---
Full diff: https://github.com/llvm/llvm-project/pull/161487.diff


3 Files Affected:

- (modified) libcxx/include/__bit/countl.h (-1) 
- (modified) libcxx/include/__bit/countr.h (-1) 
- (modified) libcxx/include/__bit/popcount.h (-1) 


``````````diff
diff --git a/libcxx/include/__bit/countl.h b/libcxx/include/__bit/countl.h
index 29b01277fb0eb..c95828f58d61a 100644
--- a/libcxx/include/__bit/countl.h
+++ b/libcxx/include/__bit/countl.h
@@ -24,7 +24,6 @@ _LIBCPP_BEGIN_NAMESPACE_STD
 
 template <class _Tp>
 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 int __countl_zero(_Tp __t) _NOEXCEPT {
-  static_assert(__is_unsigned_integer_v<_Tp>, "__countl_zero requires an unsigned integer type");
   return __builtin_clzg(__t, numeric_limits<_Tp>::digits);
 }
 
diff --git a/libcxx/include/__bit/countr.h b/libcxx/include/__bit/countr.h
index 4de887ad4f67c..16f689d6da383 100644
--- a/libcxx/include/__bit/countr.h
+++ b/libcxx/include/__bit/countr.h
@@ -24,7 +24,6 @@ _LIBCPP_BEGIN_NAMESPACE_STD
 
 template <class _Tp>
 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR int __countr_zero(_Tp __t) _NOEXCEPT {
-  static_assert(__is_unsigned_integer_v<_Tp>, "__countr_zero only works with unsigned types");
   return __builtin_ctzg(__t, numeric_limits<_Tp>::digits);
 }
 
diff --git a/libcxx/include/__bit/popcount.h b/libcxx/include/__bit/popcount.h
index 8d9ba09938482..d104c8e8f0a98 100644
--- a/libcxx/include/__bit/popcount.h
+++ b/libcxx/include/__bit/popcount.h
@@ -23,7 +23,6 @@ _LIBCPP_BEGIN_NAMESPACE_STD
 
 template <class _Tp>
 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR int __popcount(_Tp __t) _NOEXCEPT {
-  static_assert(__is_unsigned_integer_v<_Tp>, "__popcount only works with unsigned types");
   return __builtin_popcountg(__t);
 }
 

``````````

</details>


https://github.com/llvm/llvm-project/pull/161487