[PATCH] Fix PR69771, bogus CONST_INT during shift expansion

[Jakub Jelinek]

On Mon, Feb 15, 2016 at 06:58:45PM +0100, Richard Biener wrote:
> We could also force_reg those at expansion or apply SHIFT_COUNT_TRUNCATED to those invalid constants there.

Sure, but for force_reg we'd still need the gen_int_mode anyway.
As for SHIFT_COUNT_TRUNCATED, it should have been applied already from the
caller - expand_shift_1.

> >2016-02-15  Jakub Jelinek  <jakub@redhat.com>
> >
> >	PR rtl-optimization/69764
> >	PR rtl-optimization/69771
> >	* optabs.c (expand_binop): Ensure for shift optabs invalid CONST_INT
> >	op1 is valid for mode.
> >
> >--- gcc/optabs.c.jj	2016-02-12 17:49:25.000000000 +0100
> >+++ gcc/optabs.c	2016-02-15 16:15:53.983673792 +0100
> >@@ -1125,6 +1125,12 @@ expand_binop (machine_mode mode, optab b
> >       op1 = negate_rtx (mode, op1);
> >       binoptab = add_optab;
> >     }
> >+  /* For shifts, constant invalid op1 might be expanded from different
> >+     mode than MODE.  */
> >+  else if (CONST_INT_P (op1)
> >+	   && shift_optab_p (binoptab)
> >+	   && UINTVAL (op1) >= GET_MODE_BITSIZE (GET_MODE_INNER (mode)))
> >+    op1 = gen_int_mode (INTVAL (op1), mode);
> > 
> >   /* Record where to delete back to if we backtrack.  */
> >   last = get_last_insn ();

	Jakub