On Mon, 1 Jul 2019, Jan Hubicka wrote:
> Hi,
> the testcase makes inliner to substitute RESULT_DECL by COMPONENT_REF
> inside CLOBBER statement. This is not allowed and leads to ICE in
> verifier (while I think we should fix code to support this).
> This patch simply makes inliner to watch for this case and do not remap
> the statement at all.
>
> The testcase works for 32bit only which is bit unfortunate. For 64bit
> build NRV does not happen, i did not look into why.
>
> OK?
Hmm, a bit ugly and seemingly in a "wrong place" but I cannot think
of a better solution.
Thus OK.
We indeed might reconsider the CLOBBER restriction - it's from
the time they were used for stack slot sharing but now they are
re-purposed...
Thanks,
Richard.
> Honza
>
> * tree-inline.c (remap_gimple_stmt): Do not subtitute handled components
> to clobber of return value.
> * g++.dg/lto/pr90990_0.C: New testcase.
> Index: tree-inline.c
> ===================================================================
> --- tree-inline.c (revision 272846)
> +++ tree-inline.c (working copy)
> @@ -1757,6 +1757,18 @@ remap_gimple_stmt (gimple *stmt, copy_bo
> return NULL;
> }
> }
> +
> + /* We do not allow CLOBBERs of handled components. In case
> + returned value is stored via such handled component, remove
> + the clobber so stmt verifier is happy. */
> + if (gimple_clobber_p (stmt)
> + && TREE_CODE (gimple_assign_lhs (stmt)) == RESULT_DECL)
> + {
> + tree remapped = remap_decl (gimple_assign_lhs (stmt), id);
> + if (!DECL_P (remapped)
> + && TREE_CODE (remapped) != MEM_REF)
> + return NULL;
> + }
>
> if (gimple_debug_bind_p (stmt))
> {
> Index: testsuite/g++.dg/lto/pr90990_0.C
> ===================================================================
> --- testsuite/g++.dg/lto/pr90990_0.C (nonexistent)
> +++ testsuite/g++.dg/lto/pr90990_0.C (working copy)
> @@ -0,0 +1,31 @@
> +// { dg-lto-do link }
> +/* { dg-extra-ld-options { -r -nostdlib } } */
> +class A {
> +public:
> + float m_floats;
> + A() {}
> +};
> +class B {
> +public:
> + A operator[](int);
> +};
> +class C {
> + B m_basis;
> +
> +public:
> + A operator()(A) {
> + m_basis[1] = m_basis[2];
> + A a;
> + return a;
> + }
> +};
> +class D {
> +public:
> + C m_fn1();
> +};
> +class F {
> + A m_pivotInB;
> + F(D &, const A &);
> +};
> +F::F(D &p1, const A &p2) : m_pivotInB(p1.m_fn1()(p2)) {}
> +
>
--
Richard Biener <rguent...@suse.de>
SUSE Linux GmbH, Maxfeldstrasse 5, 90409 Nuernberg, Germany;
GF: Felix Imendörffer, Mary Higgins, Sri Rasiah; HRB 21284 (AG Nürnberg)
