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Re: Optimization for std::to_string()


On 20/07/18 13:51 +0300, niXman wrote:
Jonathan Wakely 2018-07-20 13:05:
On 20/07/18 12:44 +0300, niXman wrote:

Thanks. How did you verify it's an optimization?
Optimization is that there is no superfluous copying into string.

The to_string functions always pass at least __n=16 to __to_xstring,
which is larger than the SSO buffer in std::__cxx11::string, and so
forces a memory allocation.
I didn't think about this...

Avoiding an unconditional dynamic allocation is the main advantage of
using alloca.



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