Re: Common Tail Elimination


Common Tail Elimination
\ Perry Smith (23 Mar 2006)
. \ Ramana Radhakrishnan (23 Mar 2006)

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Subject:	Re: Common Tail Elimination
Group:	Gcc-help
From:	Ramana Radhakrishnan
Date:	23 Mar 2006

This is called code sinking and AFAIK this is implemented in the 4.x
series. You can also look at the code factoring branch that was being
merged into 4.2.

> Does gcc/g++ have what I think is called "common tail elimination"?
> If a function does: step a, step b, step c, return val; in more than
> one place, will the common code be pulled out and branched to in
> order to reduce the size of the code? This may be contrary to most
> optimizations since it introduces a branch which costs time but the
> benefit is smaller code size.
>
> Thanks,
> Perry
>

----
Ramana Radhakrishnan
GNU Tools
Codito Technologies