Factoring algorithms on rtl ?

[Jim Wilson]

GĂĄbor LĂłki wrote:
> The attached patch finds those basic blocks of which the first insns
> are indentical, and factor out them into the end of parent basic blocks.
> This is done only if it has no side effects and the count of original
> insns - marked for factoring - is greater than the count of parent basic
> blocks.

This seems to be the same optmization as cross-jumping, except that 
cross-jumping only handles the suffix case, and you are trying to handle 
both prefix and suffix cases.

See try_crossjump_bb in cfgcleanup.c.
-- 
Jim Wilson, GNU Tools Support, http://www.SpecifixInc.com