[Bug rtl-optimization/60763] [4.9 Regression] ICE in extract_insn starting with rev 208984

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60763

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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                 CC|                            |jakub at gcc dot gnu.org

--- Comment #12 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
(In reply to David Edelsohn from comment #10)
> I'm not questioning the analysis, I'm questioning the solution. Directly
> generating a register and jamming in the REGNO in this pattern seems sort of
> crude.
> 
> gen_rtx_REG (DImode, REGNO (op0));

I think this idiom is very commonly used in other backends for this purpose,
and is simple enough not to need any kind of extra wrapper.
Just look e.g. at
grep gen_rtx_REG' '.*REGNO gcc/config/i386/*.md

Perhaps a one line comment would be useful, but other than that the #c7 patch
looks just fine to me.