Re: [PATCH 2/n] OpenMP 4.0 offloading infrastructure: LTO streaming

[Jakub Jelinek <jakub@redhat.com>]

On Tue, Oct 28, 2014 at 10:30:47PM +0300, Ilya Verbin wrote:
> --- a/gcc/cgraph.c
> +++ b/gcc/cgraph.c
> @@ -70,6 +70,7 @@ along with GCC; see the file COPYING3.  If not see
>  #include "tree-dfa.h"
>  #include "profile.h"
>  #include "params.h"
> +#include "context.h"
>  
>  /* FIXME: Only for PROP_loops, but cgraph shouldn't have to know about this.  */
>  #include "tree-pass.h"
> @@ -474,6 +475,13 @@ cgraph_node::create (tree decl)
>    gcc_assert (TREE_CODE (decl) == FUNCTION_DECL);
>  
>    node->decl = decl;
> +
> +  if (lookup_attribute ("omp declare target", DECL_ATTRIBUTES (decl)))
> +    {
> +      node->offloadable = 1;
> +      g->have_offload = true;
> +    }

I wonder if we shouldn't optimize here and call lookup_attribute only
if there is a chance that the attribute might be present, so guard with
flag_openmp (and flag_openacc later on?).  During LTO the cgraph nodes
are streamed in and supposedly the flag offloadable too.

> @@ -2129,8 +2141,12 @@ symbol_table::compile (void)
>      fprintf (stderr, "Performing interprocedural optimizations\n");
>    state = IPA;
>  
> +  /* OpenMP offloading requires LTO infrastructure.  */
> +  if (!in_lto_p && flag_openmp && g->have_offload)
> +    flag_generate_lto = 1;

On the other side, do you need flag_openmp here?  Supposedly g->have_offload
would already been set if needed.

	Jakub