Re: patch to improve i386 epilogue (version 5)

[John Wehle <john at feith dot com>]

> Am I missing something, or are you working way too hard for this?
> 
> /* EXIT_IGNORE_STACK should be nonzero if, when returning from a function,
>    the stack pointer does not matter.  The value is tested only in
>    functions that have frame pointers.
>    No definition is equivalent to always zero.  */
> /* Note on the 386 it might be more efficient not to define this since 
>    we have to restore it ourselves from the frame pointer, in order to
>    use pop */
> 
> #define EXIT_IGNORE_STACK 1

I belive that not defining EXIT_IGNORE_STACK disables some useful
optimizations.  The idea is to let gcc do these optimizations
and to simply notice when they haven't been done which means that
the stack pointer doesn't need to be reloaded.

-- John
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