On Fri, 11 Mar 2016, Jakub Jelinek wrote:
> Hi!
>
> The following testcase ICEs on i?86/x86_64 and aarch64, because gen_lowpart
> (pointer to gen_lowpart_general at that spot) doesn't want to handle
> SUBREG of SYMBOL_REF. Fixed by using a variant that doesn't ICE and forcing
> the operand into a register if it can't be optimized without generating
> instructions. This is similar to the case a few lines above, where we also
> force_reg if simplify_subreg failed.
>
> Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
Ok.
Thanks,
Richard.
> 2016-03-11 Jakub Jelinek <ja...@redhat.com>
>
> PR rtl-optimization/70174
> * expmed.c (store_bit_field_using_insv): Use gen_lowpart_if_possible
> followed by gen_lowpart on force_reg instead of just gen_lowpart.
>
> * gcc.dg/pr70174.c: New test.
>
> --- gcc/expmed.c.jj 2016-02-11 20:28:51.000000000 +0100
> +++ gcc/expmed.c 2016-03-11 10:40:27.258719168 +0100
> @@ -658,24 +658,28 @@ store_bit_field_using_insv (const extrac
> {
> if (GET_MODE_BITSIZE (GET_MODE (value)) >= bitsize)
> {
> + rtx tmp;
> /* Optimization: Don't bother really extending VALUE
> if it has all the bits we will actually use. However,
> if we must narrow it, be sure we do it correctly. */
>
> if (GET_MODE_SIZE (GET_MODE (value)) < GET_MODE_SIZE (op_mode))
> {
> - rtx tmp;
> -
> tmp = simplify_subreg (op_mode, value1, GET_MODE (value), 0);
> if (! tmp)
> tmp = simplify_gen_subreg (op_mode,
> force_reg (GET_MODE (value),
> value1),
> GET_MODE (value), 0);
> - value1 = tmp;
> }
> else
> - value1 = gen_lowpart (op_mode, value1);
> + {
> + tmp = gen_lowpart_if_possible (op_mode, value1);
> + if (! tmp)
> + tmp = gen_lowpart (op_mode, force_reg (GET_MODE (value),
> + value1));
> + }
> + value1 = tmp;
> }
> else if (CONST_INT_P (value))
> value1 = gen_int_mode (INTVAL (value), op_mode);
> --- gcc/testsuite/gcc.dg/pr70174.c.jj 2016-03-11 10:42:45.914894656 +0100
> +++ gcc/testsuite/gcc.dg/pr70174.c 2016-03-11 10:42:31.000000000 +0100
> @@ -0,0 +1,11 @@
> +/* PR rtl-optimization/70174 */
> +/* { dg-do compile } */
> +/* { dg-options "-O2" } */
> +
> +struct S { int f : 4; } a;
> +
> +void
> +foo (void)
> +{
> + a.f = foo; /* { dg-warning "assignment makes integer from pointer without
> a cast" } */
> +}
>
> Jakub
>
>
--
Richard Biener <rguent...@suse.de>
SUSE LINUX GmbH, GF: Felix Imendoerffer, Jane Smithard, Graham Norton, HRB
21284 (AG Nuernberg)
