On Sat, Feb 13, 2016 at 07:50:25AM +0000, James Greenhalgh wrote:
> On Fri, Feb 12, 2016 at 05:34:21PM +0100, Jakub Jelinek wrote:
> > On Fri, Feb 12, 2016 at 03:20:07PM +0100, Bernd Schmidt wrote:
> > > >>- mode1 = GET_MODE (xop1) != VOIDmode ? GET_MODE (xop1) : mode;
> > > >>+ mode1 = GET_MODE (xop1) != VOIDmode ? GET_MODE (xop1) : mode1;
> > > >> if (xmode1 != VOIDmode && xmode1 != mode1)
> > > >> {
> > >
> > > Here, things aren't so clear, and the fact that the mode1 calculation now
> > > differs from the mode0 one may be overlooked by someone in the future.
> > >
> > > Rather than use codes like "mode variable is VOIDmode", I'd prefer to use
> > > booleans with descriptive names, like "op1_may_need_conversion".
> >
> > So do you prefer e.g. following? Bootstrapped/regtested on x86_64-linux and
> > i686-linux.
> >
> > 2016-02-12 Jakub Jelinek <ja...@redhat.com>
> >
> > PR rtl-optimization/69764
> > PR rtl-optimization/69771
> > * optabs.c (expand_binop_directly): For shift_optab_p, force
> > convert_modes with VOIDmode if xop1 has VOIDmode.
> >
> > * c-c++-common/pr69764.c: New test.
> > * gcc.dg/torture/pr69771.c: New testcase.
> >
>
> These two new tests are failing for me on AArch64 as so:
As I said earlier, I wanted to fix it in expand_binop_directly because the
higher levels still GEN_INT the various shift counters and then call
expand_binop_directly. But, as can be seen on aarch64/arm/m68k, there are
cases that need op1 to be valid for mode already in expand_binop, so in
addition to the already committed fix I think we need to handle it
at the expand_binop level too.
As we don't have a single spot with convert_modes like
expand_binop_directly, I think the best is to do there a change
for the uncommon and invalid cases only, like (seems to fix the ICE
both on aarch64 and m68k):
2016-02-15 Jakub Jelinek <ja...@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
