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Re: [PATCH] combine: Allow combining two insns to two insns
On Wed, Jul 25, 2018 at 09:47:31AM -0400, David Malcolm wrote:
> > +/* Return whether X is just a single set, with the source
> > + a general_operand. */
> > +static bool
> > +is_just_move (rtx x)
> > +{
> > + if (INSN_P (x))
> > + x = PATTERN (x);
> > +
> > + return (GET_CODE (x) == SET && general_operand (SET_SRC (x),
> > VOIDmode));
> > +}
>
> If I'm reading it right, the patch only calls this function on i2 and
> i3, which are known to be rtx_insn *, rather than just rtx.
I used to also have
is_just_move (XVECEXP (newpat, 0, 0))
etc.; during most of combine you do not have instructions, just patterns.
Segher