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Re: Improve unrolled size estimates
>> +struct loop_size
>> + /* Number of instructions in the loop. */
>> + int overall;
>> + /* Number of instructions that will be likely optimized out in
>> + peeled iterations of loop (i.e. computation based on induction
>> + variable where induction variable starts at known constant.) */
>> + int eliminated_by_peeling;
Space after "int foo;" lines.
> Is it worth handling this very special case? Note that you are
> recursively asking for stuff again, so this may become quadratic,
> especially as simple_iv isn't exactly very cheap.
Why instead not using two bitmaps for known-yes and known-no results of
constant_after_peeling for SSA_NAMEs? Or alternatively a cache of
simple_iv results; I would like to use simple_iv in VRP too, to get good
bounds for simple instance variables instead of punting to
[something,+INF]. I'm not negative at all about Honza's approach with
one of these changes.