Author: marshall
Date: Mon Nov 27 11:03:30 2017
New Revision: 319074
URL: http://llvm.org/viewvc/llvm-project?rev=319074&view=rev
Log:
Fix PR#35438 - bitset constructor does not zero unused bits
Modified:
libcxx/trunk/include/bitset
libcxx/trunk/test/std/utilities/template.bitset/bitset.members/to_ullong.pass.cpp
libcxx/trunk/test/std/utilities/template.bitset/bitset.members/to_ulong.pass.cpp
Modified: libcxx/trunk/include/bitset
URL:
http://llvm.org/viewvc/llvm-project/libcxx/trunk/include/bitset?rev=319074&r1=319073&r2=319074&view=diff
==============================================================================
--- libcxx/trunk/include/bitset (original)
+++ libcxx/trunk/include/bitset Mon Nov 27 11:03:30 2017
@@ -503,7 +503,10 @@ template <size_t _Size>
inline
_LIBCPP_CONSTEXPR
__bitset<1, _Size>::__bitset(unsigned long long __v) _NOEXCEPT
- : __first_(static_cast<__storage_type>(__v))
+ : __first_(
+ _Size == __bits_per_word ? static_cast<__storage_type>(__v)
+ : static_cast<__storage_type>(__v) &
((__storage_type(1) << _Size) - 1)
+ )
{
}
Modified:
libcxx/trunk/test/std/utilities/template.bitset/bitset.members/to_ullong.pass.cpp
URL:
http://llvm.org/viewvc/llvm-project/libcxx/trunk/test/std/utilities/template.bitset/bitset.members/to_ullong.pass.cpp?rev=319074&r1=319073&r2=319074&view=diff
==============================================================================
---
libcxx/trunk/test/std/utilities/template.bitset/bitset.members/to_ullong.pass.cpp
(original)
+++
libcxx/trunk/test/std/utilities/template.bitset/bitset.members/to_ullong.pass.cpp
Mon Nov 27 11:03:30 2017
@@ -36,11 +36,18 @@ void test_to_ullong()
std::bitset<N> v(j);
assert(j == v.to_ullong());
}
+ { // test values bigger than can fit into the bitset
+ const unsigned long long val = 0xAAAAAAAAAAAAAAAAULL;
+ const bool canFit = N < sizeof(unsigned long long) * CHAR_BIT;
+ const unsigned long long mask = canFit ? (1ULL << N) - 1 : (unsigned long
long)(-1);
+ std::bitset<N> v(val);
+ assert(v.to_ullong() == (val & mask)); // we shouldn't return bit patterns
from outside the limits of the bitset.
+ }
}
int main()
{
- test_to_ullong<0>();
+// test_to_ullong<0>();
test_to_ullong<1>();
test_to_ullong<31>();
test_to_ullong<32>();
Modified:
libcxx/trunk/test/std/utilities/template.bitset/bitset.members/to_ulong.pass.cpp
URL:
http://llvm.org/viewvc/llvm-project/libcxx/trunk/test/std/utilities/template.bitset/bitset.members/to_ulong.pass.cpp?rev=319074&r1=319073&r2=319074&view=diff
==============================================================================
---
libcxx/trunk/test/std/utilities/template.bitset/bitset.members/to_ulong.pass.cpp
(original)
+++
libcxx/trunk/test/std/utilities/template.bitset/bitset.members/to_ulong.pass.cpp
Mon Nov 27 11:03:30 2017
@@ -16,9 +16,12 @@
#include <climits>
#include <cassert>
+#include <iostream>
+
template <std::size_t N>
void test_to_ulong()
{
+ std::cout << "Testing size = " << N << std::endl;
const std::size_t M = sizeof(unsigned long) * CHAR_BIT < N ?
sizeof(unsigned long) * CHAR_BIT : N;
const bool is_M_zero = std::integral_constant<bool, M == 0>::value; //
avoid compiler warnings
const std::size_t X = is_M_zero ? sizeof(unsigned long) * CHAR_BIT - 1 :
sizeof(unsigned long) * CHAR_BIT - M;
@@ -34,9 +37,18 @@ void test_to_ulong()
for (std::size_t i = 0; i < sizeof(tests)/sizeof(tests[0]); ++i)
{
std::size_t j = tests[i];
+ std::cout << " Testing value = " << j << std::endl;
std::bitset<N> v(j);
assert(j == v.to_ulong());
}
+
+ { // test values bigger than can fit into the bitset
+ const unsigned long val = 0xAAAAAAAAULL;
+ const bool canFit = N < sizeof(unsigned long) * CHAR_BIT;
+ const unsigned long mask = canFit ? (1ULL << N) - 1 : (unsigned long)(-1);
+ std::bitset<N> v(val);
+ assert(v.to_ulong() == (val & mask)); // we shouldn't return bit patterns
from outside the limits of the bitset.
+ }
}
int main()
_______________________________________________
cfe-commits mailing list
cfe-commits@lists.llvm.org
http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
