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Re: Delayed branch scheduling pass destroys the CFG data?


On 6/27/06, Minh D. Nguyen <nguyen@eit.uni-kl.de> wrote:
I though the problem is that the delayed branch scheduling pass changes the
some instructions for the delayed branch, but it does not change the control
flow graph data.

It does not change the control flow graph. It destroys it. It doesn't even really know that there is a CFG and it makes no attempt to keep it up-to-date. It would take a rewrite of both reorg itself and of the whole CFG support infrastructure in GCC to make it possible to have a CFG after reorg. The current CFG infrastructure cannot handle the SEQUENCE pseudo-insns used to represent delay slots.

Gr.
Steven


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