Re: [PATCH] Fix ICE when __builtin_calloc has no LHS (PR tree-optimization/91014).

[Thomas Schwinge]

Hi!

Curious: even if you found the issue on a s390x target, shouldn't this
(presumably generic?) test case live in a generic place instead of
'gcc.target/s390/'?


Grüße
 Thomas


On 2019-06-27T11:21:33+0200, Martin Liška <mli...@suse.cz> wrote:
> This is quite an obvious changes I've noticed during fuzzing
> of s390x target compiler.
>
> Patch can bootstrap on x86_64-linux-gnu and survives regression tests.
>
> Ready to be installed?
> Thanks,
> Martin
>
> gcc/ChangeLog:
>
> 2019-06-27  Martin Liska  <mli...@suse.cz>
>
>       PR tree-optimization/91014
>       * tree-ssa-dse.c (initialize_ao_ref_for_dse): Bail out
>       when LHS is NULL_TREE.
>
> gcc/testsuite/ChangeLog:
>
> 2019-06-27  Martin Liska  <mli...@suse.cz>
>
>       PR tree-optimization/91014
>       * gcc.target/s390/pr91014.c: New test.
> ---
>  gcc/testsuite/gcc.target/s390/pr91014.c | 8 ++++++++
>  gcc/tree-ssa-dse.c                      | 5 +++--
>  2 files changed, 11 insertions(+), 2 deletions(-)
>  create mode 100644 gcc/testsuite/gcc.target/s390/pr91014.c
>
>
> diff --git a/gcc/testsuite/gcc.target/s390/pr91014.c 
> b/gcc/testsuite/gcc.target/s390/pr91014.c
> new file mode 100644
> index 00000000000..eb37b333b5b
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/s390/pr91014.c
> @@ -0,0 +1,8 @@
> +/* { dg-do compile } */
> +/* { dg-options "-O" } */
> +/* { dg-require-effective-target alloca } */
> +
> +void foo(void)
> +{
> + __builtin_calloc (1, 1); /* { dg-warning "ignoring return value of 
> '__builtin_calloc' declared with attribute 'warn_unused_result'" } */
> +}
> diff --git a/gcc/tree-ssa-dse.c b/gcc/tree-ssa-dse.c
> index 1b1a9f34230..df05a55ce78 100644
> --- a/gcc/tree-ssa-dse.c
> +++ b/gcc/tree-ssa-dse.c
> @@ -129,10 +129,11 @@ initialize_ao_ref_for_dse (gimple *stmt, ao_ref *write)
>           {
>             tree nelem = gimple_call_arg (stmt, 0);
>             tree selem = gimple_call_arg (stmt, 1);
> +           tree lhs;
>             if (TREE_CODE (nelem) == INTEGER_CST
> -               && TREE_CODE (selem) == INTEGER_CST)
> +               && TREE_CODE (selem) == INTEGER_CST
> +               && (lhs = gimple_call_lhs (stmt)) != NULL_TREE)
>               {
> -               tree lhs = gimple_call_lhs (stmt);
>                 tree size = fold_build2 (MULT_EXPR, TREE_TYPE (nelem),
>                                          nelem, selem);
>                 ao_ref_init_from_ptr_and_size (write, lhs, size);