Re: [PATCH] Fix VTA ICE (PR debug/45259)

[Richard Guenther <richard dot guenther at gmail dot com>]

On Thu, Aug 12, 2010 at 10:10 AM, Jakub Jelinek <jakub@redhat.com> wrote:
> Hi!
>
> When fixing PR42918, I wasn't aware of reload chain pointing also to
> insns before basic block (like jump tables) with ->block number of the
> following bb. ?The moving of notes in that case is both completely
> unnecessary (as the jump tables etc. certainly can't cause any register
> saves, therefore there is nothing to restore), but doesn't work (both
> in that it tries to move around block notes and that it fails assertion
> because it sees CODE_LABEL or BARRIER insns, which is neither a NOTE nor
> DEBUG_INSN nor last->insn.
>
> Fixed thusly, bootstrapped/regtested on x86_64-linux and i686-linux.
> Ok for trunk/4.5?

Ok.

Thanks,
Richard.

> 2010-08-12 ?Jakub Jelinek ?<jakub@redhat.com>
>
> ? ? ? ?PR debug/45259
> ? ? ? ?* caller-save.c (save_call_clobbered_regs): Only swap notes with
> ? ? ? ?DEBUG_INSNs if n_regs_saved.
>
> ? ? ? ?* gcc.dg/pr45259.c: New test.
>
> --- gcc/caller-save.c.jj ? ? ? ?2010-08-11 21:08:06.000000000 +0200
> +++ gcc/caller-save.c ? 2010-08-11 22:23:12.000000000 +0200
> @@ -868,7 +868,10 @@ save_call_clobbered_regs (void)
> ? ? ? ? ? ? remain saved. ?If the last insn in the block is a JUMP_INSN, put
> ? ? ? ? ? ? the restore before the insn, otherwise, put it after the insn. ?*/
>
> - ? ? ? ? if (DEBUG_INSN_P (insn) && last && last->block == chain->block)
> + ? ? ? ? if (n_regs_saved
> + ? ? ? ? ? ? && DEBUG_INSN_P (insn)
> + ? ? ? ? ? ? && last
> + ? ? ? ? ? ? && last->block == chain->block)
> ? ? ? ? ? ?{
> ? ? ? ? ? ? ?rtx ins, prev;
> ? ? ? ? ? ? ?basic_block bb = BLOCK_FOR_INSN (insn);
> --- gcc/testsuite/gcc.dg/pr45259.c.jj ? 2010-08-11 22:12:19.000000000 +0200
> +++ gcc/testsuite/gcc.dg/pr45259.c ? ? ?2010-08-11 21:43:24.000000000 +0200
> @@ -0,0 +1,42 @@
> +/* PR debug/45259 */
> +/* { dg-do compile } */
> +/* { dg-options "-g -O2 -fpic -w" { target fpic } } */
> +
> +struct S { void (*bar) (long); };
> +struct T { struct S *t; };
> +int w;
> +extern int baz (int);
> +
> +void
> +foo (int x, int u, char *z)
> +{
> + ?struct T *v;
> + ?static void *y[256] = { &&l1, &&l2 };
> + ?for (;;)
> + ? ?switch (x)
> + ? ? ?{
> + ? ? ?l2:
> + ? ? ? x = 9;
> + ? ? ?case 9:
> + ? ? ? goto *y[*z++];
> + ? ? ?case 10:
> + ? ? ?case 27:
> + ? ? ?case 54:
> + ? ? ?case 99:
> + ? ? ?case 100:
> + ? ? ?case 120:
> + ? ? ?case 122:
> + ? ? ?case 131:
> + ? ? ?case 132:
> + ? ? ?case 134:
> + ? ? ?case 141:
> + ? ? ?case 142:
> + ? ? ? v->t->bar (u);
> + ? ? ? v->t->bar (u);
> + ? ? ?case 143:
> + ? ? ? continue;
> + ? ? ?l1:
> + ? ? ?default:
> + ? ? ? baz (w);
> + ? ? ?}
> +}
>
> ? ? ? ?Jakub
>