[committed] libstdc++: Add [[unlikely]] attributes to std::random_device routines
Commit Message
Tested x86+64-linux, pushed to trunk.
libstdc++-v3/ChangeLog:
* src/c++11/random.cc (__x86_rdrand, __x86_rdseed): Add
[[unlikely]] attribute.
---
libstdc++-v3/src/c++11/random.cc | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
@@ -97,7 +97,7 @@ namespace std _GLIBCXX_VISIBILITY(default)
unsigned int retries = 100;
unsigned int val;
- while (__builtin_ia32_rdrand32_step(&val) == 0)
+ while (__builtin_ia32_rdrand32_step(&val) == 0) [[__unlikely__]]
if (--retries == 0)
std::__throw_runtime_error(__N("random_device: rdrand failed"));
@@ -113,7 +113,7 @@ namespace std _GLIBCXX_VISIBILITY(default)
unsigned int retries = 100;
unsigned int val;
- while (__builtin_ia32_rdseed_si_step(&val) == 0)
+ while (__builtin_ia32_rdseed_si_step(&val) == 0) [[__unlikely__]]
{
if (--retries == 0)
{