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Re: missing conditional propagation in cprop.c pass
> Unless there's something arch specific related to arm, insn 882 is a
> compare, which won't change r684. Why do you think 0 should
> propagated to r291 if r684 is not zero?
>
Thanks for replying.
Sorry if I misunderstood anything below, and please correct me.
insn 882 : cc <- compare (r684, 0)
jump_insn 883 : if (cc != 0) goto insn 46
insn 49 : r291 <- r684
......
insn 46
cc contains the result of subtracting 0 from r684;
control flow goes to insn_49 only if (cc == 0), which implies (r684 == 0).
Then at insn_49 we have conditional const propagation "r684 <- 0", is it right?
Thanks again.
--
Best Regards.