std::pow implementation

[Richard Guenther]

On 29 Jul 2003, Gabriel Dos Reis wrote:

> Richard Guenther <rguenth@tat.physik.uni-tuebingen.de> writes:
>
> | It has been shown that the current gcc unroller is not able to
> | unroll the while loop in std::__cmath_power() and such even inlining
> | does not help to create good code. Also inlining the loop if it is
> | not unrolled and its contents not sufficiently cprop'ed is harmful.
>
> If you find that after inlining, the status of "constant expression"
> is not recognized then I'd encourage you to fill a PR.

The problem is the loop optimizer not being able to compute the number of
iterations here. PR optimization/11710 - though unfortunately not a
regression. Can anyone check if this is fixed on rtlopt (one more reason
to merge it)?

Richard.