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Re: combine_simplify_rtx fix


>     Applying distributive law may change mode of OP0 in case subregs are
>     present.  The op0_mode then contains bogus value, as was caught by
>     testing code in other patch.
> 
> Can you give an example of the before-and-after RTL: this seems
> counterintuitive to me.

The function in question is responsible for simplifications like:
(subreg:QI (ior:SI (reg:SI 75)
        (reg:SI 70)) 0)

(ior:QI (subreg:QI (reg:SI 75) 0)
    (subreg:QI (reg:SI 70) 0))

Honza


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