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Re: [RFC] Unconditionally clean up CFG before emitting prologue


On Mon, Apr 9, 2012 at 6:11 PM, Eric Botcazou <ebotcazou@adacore.com> wrote:
>> Isn't the gimple cfg-cleanup we run post optimization (right before
>> expansion) not enough? ?Or the cfg-cleanup we perform right after expansion
>> now? At least if the branches are really caused by the gimplification
>> process I would expect things to be cleaned up at this point, no?
>
> At least the patch has a non-null (albeit minor) effect, which pertains mainly
> to jump threading (typical diff attached, Ada code at -O0 on x86-64).

So it's trivial forwarders that are removed.  I wonder why cfgcleanup on the
tree level does not do this, or why it does that on the RTL level.  Are the
blocks becoming empty only during/after register allocation?

Richard.

> --
> Eric Botcazou


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