On Tue, 27 Jun 2017, Jakub Jelinek wrote:
> Hi!
>
> replace_call_with_call_and_fold has code to copy over vdef/vuse from the
> old call to the new one, so that we don't have to update virtual ssa,
> but it is conditioned on gimple_vdef being non-NULL and SSA_NAME.
> If we have a pure function, gimple_vdef is NULL, yet we still want to copy
> over the vuse.
>
> Bootstrapped/regtested on x86_64-linux (i686-linux fails to bootstrap
> with/without this patch), ok for trunk?
Ok with ...
> 2017-06-27 Jakub Jelinek <ja...@redhat.com>
>
> PR middle-end/81207
> * gimple-fold.c (replace_call_with_call_and_fold): Handle
> gimple_vuse copying separately from gimple_vdef copying.
>
> * gcc.c-torture/compile/pr81207.c: New test.
>
> --- gcc/gimple-fold.c.jj 2017-06-19 08:28:11.000000000 +0200
> +++ gcc/gimple-fold.c 2017-06-26 17:09:34.735420583 +0200
> @@ -607,9 +607,11 @@ replace_call_with_call_and_fold (gimple_
> && TREE_CODE (gimple_vdef (stmt)) == SSA_NAME)
> {
> gimple_set_vdef (repl, gimple_vdef (stmt));
> - gimple_set_vuse (repl, gimple_vuse (stmt));
> SSA_NAME_DEF_STMT (gimple_vdef (repl)) = repl;
> }
> + if (gimple_vuse (stmt)
> + && TREE_CODE (gimple_vuse (stmt)) == SSA_NAME)
... the SSA_NAME check removed. It's done above because we access
SSA_NAME_DEF_STMT, here it isn't necessary.
> + gimple_set_vuse (repl, gimple_vuse (stmt));
> gsi_replace (gsi, repl, false);
> fold_stmt (gsi);
> }
> --- gcc/testsuite/gcc.c-torture/compile/pr81207.c.jj 2017-06-26
> 17:21:38.765918367 +0200
> +++ gcc/testsuite/gcc.c-torture/compile/pr81207.c 2017-06-26
> 17:27:15.222966965 +0200
> @@ -0,0 +1,13 @@
> +/* PR middle-end/81207 */
> +
> +static const char *b[2] = { "'", "" };
> +
> +int
> +foo (const char *d)
> +{
> + int e;
> + for (e = 0; b[e]; e++)
> + if (__builtin_strstr (d, b[e]))
> + return 1;
> + return 0;
> +}
>
> Jakub
>
>
--
Richard Biener <rguent...@suse.de>
SUSE LINUX GmbH, GF: Felix Imendoerffer, Jane Smithard, Graham Norton, HRB
21284 (AG Nuernberg)
