On Wed, 14 Mar 2018, Jakub Jelinek wrote:
> Hi!
>
> prepare_cmp_insn in some cases changes both the passed in comparison and the
> comparison mode, e.g. by promoting the arguments from SFmode to DFmode etc.
>
> In emit_conditional_move we call this in a loop, for (pass = 0; pass < 2;
> pass++)
> and in each case construct comparison arguments as well as the comparison
> passed to it from the original arguments (we have to after all, because when
> not successful, we throw the whole insn sequence away), but use cmode which
> the first iteration could have changed, on this testcase on powerpcspe with
> -mcpu=8548 from SFmode to DFmode, so we ICE the second time, because the
> arguments don't really match the comparison mode.
>
> Fixed by passing it an address of a copy of the cmode parameter, so that the
> second pass starts with the original cmode that matches the arguments again.
>
> Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
Ok.
Richard.
> 2018-03-14 Jakub Jelinek <ja...@redhat.com>
>
> PR target/84860
> * optabs.c (emit_conditional_move): Pass address of cmode's copy
> rather than address of cmode as last argument to prepare_cmp_insn.
>
> * gcc.c-torture/compile/pr84860.c: New test.
>
> --- gcc/optabs.c.jj 2018-02-09 19:11:29.000000000 +0100
> +++ gcc/optabs.c 2018-03-14 09:22:31.707873477 +0100
> @@ -4345,9 +4345,10 @@ emit_conditional_move (rtx target, enum
> save_pending_stack_adjust (&save);
> last = get_last_insn ();
> do_pending_stack_adjust ();
> + machine_mode cmpmode = cmode;
> prepare_cmp_insn (XEXP (comparison, 0), XEXP (comparison, 1),
> GET_CODE (comparison), NULL_RTX, unsignedp,
> - OPTAB_WIDEN, &comparison, &cmode);
> + OPTAB_WIDEN, &comparison, &cmpmode);
> if (comparison)
> {
> struct expand_operand ops[4];
> --- gcc/testsuite/gcc.c-torture/compile/pr84860.c.jj 2018-03-14
> 09:26:19.988883506 +0100
> +++ gcc/testsuite/gcc.c-torture/compile/pr84860.c 2018-03-14
> 09:26:44.854884590 +0100
> @@ -0,0 +1,11 @@
> +/* PR target/84860 */
> +
> +void
> +foo (int x, int y)
> +{
> + while (x < 1)
> + {
> + x = y;
> + y = ((float)1 / 0) ? 2 : 0;
> + }
> +}
>
> Jakub
>
>
--
Richard Biener <rguent...@suse.de>
SUSE LINUX GmbH, GF: Felix Imendoerffer, Jane Smithard, Graham Norton, HRB
21284 (AG Nuernberg)
