An issue for the SC: horrible documentation quality of GCC

[Zdenek Dvorak]

Hello,

>     Then you will end up with never ending dataflow problems in the global
>     pass.  The GCSE in the simplest definition is already too complicated
>     for us to be implemented correctly (we are on it since 97 and still it
>     is inferrior to what is done by other compilers).  Adding more
>     complexity, like CSE has would make it more crazier.
> 
> Perhaps, but a lot of that complexity is *needed*.  The reason that GCC
> has historically beaten other compilers in code quality is paying attention 
> to important heuristics and less on "textbook" material.  Sure the latter
> is also critical, but the pragmatics cannot be ignored.

the problem with this approach is that you will eventually end up with
an uncomprehensible piece of code where everything depends on everything
and you cannot do a simplest change without everything else falling
apart.

GCSE is basically machine independent, so there should not be a need for
it to take machine-dependent issues into accout. These dependencies
should be isolated in a few later passses that can take care of the
issues you mention without harming each other.

Zdenek