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Re: GCC-How does the coding style affect the insv pattern recognization?
2010/1/18 Adam Nemet <adambnemet@gmail.com>:
> Sorry for jumping in late. ?See make_file_assigment in combine.c.
>
> The problem usually is that:
>
> ?(set A (ior (and B C1) OTHER))
>
> can only be turned into a bit-insertion if A and B happen to be the same
> pseudos.
>
> Adam
>
Thank you, Adam. The problem is that before combine pass the
statement is expressed in 6 insns. The insns can't be combined into
the expected pattern (set A (ior (and B C1) OTHER)). Otherwise,
make_field_assignment can do the job of simplifying the SET insn.
Qifei Fan