Fix PR34916, 35519 Combine (Dataflow merge regression.)
Paolo Bonzini
bonzini@gnu.org
Wed Mar 19 07:52:00 GMT 2008
> The log_links list being walked is very short - only one element per
> immediately linked instruction. So typical length is perhaps 2 (without
> duplicates). The largest would be for an instruction which has many
> input operands where each is the output of an instructions in same
> block, with no intervening usage. Maybe a libcall call of some type.
> But still short list!
I agree, create_log_links doesn't even add LOG_LINKS to asms, which
potentially have a lot of uses. I think this is entirely comparable to
using insertion sort because you know the size of the array is small.
I cannot approve this though (and would not like to override Richi anyway).
Paolo
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