Explicitly list all tree codes in gcc/tree-streamer.c:record_common_node (was: [PR lto/77458] Avoid ICE in offloading with differing _FloatN, _FloatNx types)

Hi Richard!

On Mon, 19 Sep 2016 13:25:01 +0200, Richard Biener <richard.guenther@gmail.com> wrote:
> On Mon, Sep 19, 2016 at 1:19 PM, Thomas Schwinge
> <thomas@codesourcery.com> wrote:
> > On Mon, 19 Sep 2016 10:18:35 +0200, Richard Biener <richard.guenther@gmail.com> wrote:
> >> On Fri, Sep 16, 2016 at 3:32 PM, Thomas Schwinge
> >> <thomas@codesourcery.com> wrote:
> >> > --- gcc/tree-streamer.c
> >> > +++ gcc/tree-streamer.c
> >> > @@ -278,9 +278,23 @@ record_common_node (struct streamer_tree_cache_d *cache, tree node)
> >> >    streamer_tree_cache_append (cache, node, cache->nodes.length ());
> >> >
> >> >    if (POINTER_TYPE_P (node)
> >> > -      || TREE_CODE (node) == COMPLEX_TYPE
> >> >        || TREE_CODE (node) == ARRAY_TYPE)
> >> >      record_common_node (cache, TREE_TYPE (node));
> >> > +  else if (TREE_CODE (node) == COMPLEX_TYPE)
> >> > [...]
> >> >    else if (TREE_CODE (node) == RECORD_TYPE)

> [looks to me we miss handling of vector type components alltogether,
> maybe there are no global vector type trees ...]

Looks like it, yes.  Would a patch like the following be reasonable,
which explicitly lists/handles all expected tree codes, or is something
like that not feasible?  (That's a subset of tree codes I gathered by a
partial run of the GCC testsuite, and libgomp testsuite; not claiming
this is complete.)

commit f28dd9618be8a26c6a75ee089f1755e4e0281106
Author: Thomas Schwinge <thomas@codesourcery.com>
Date:   Thu Sep 29 16:35:19 2016 +0200

    Explicitly list all tree codes in gcc/tree-streamer.c:record_common_node
---
 gcc/tree-streamer.c | 32 +++++++++++++++++++++++++-------
 1 file changed, 25 insertions(+), 7 deletions(-)



Grüße
 Thomas

On Thu, Sep 29, 2016 at 4:48 PM, Thomas Schwinge
<thomas@codesourcery.com> wrote:
> Hi Richard!
>
> On Mon, 19 Sep 2016 13:25:01 +0200, Richard Biener <richard.guenther@gmail.com> wrote:
>> On Mon, Sep 19, 2016 at 1:19 PM, Thomas Schwinge
>> <thomas@codesourcery.com> wrote:
>> > On Mon, 19 Sep 2016 10:18:35 +0200, Richard Biener <richard.guenther@gmail.com> wrote:
>> >> On Fri, Sep 16, 2016 at 3:32 PM, Thomas Schwinge
>> >> <thomas@codesourcery.com> wrote:
>> >> > --- gcc/tree-streamer.c
>> >> > +++ gcc/tree-streamer.c
>> >> > @@ -278,9 +278,23 @@ record_common_node (struct streamer_tree_cache_d *cache, tree node)
>> >> >    streamer_tree_cache_append (cache, node, cache->nodes.length ());
>> >> >
>> >> >    if (POINTER_TYPE_P (node)
>> >> > -      || TREE_CODE (node) == COMPLEX_TYPE
>> >> >        || TREE_CODE (node) == ARRAY_TYPE)
>> >> >      record_common_node (cache, TREE_TYPE (node));
>> >> > +  else if (TREE_CODE (node) == COMPLEX_TYPE)
>> >> > [...]
>> >> >    else if (TREE_CODE (node) == RECORD_TYPE)
>
>> [looks to me we miss handling of vector type components alltogether,
>> maybe there are no global vector type trees ...]
>
> Looks like it, yes.  Would a patch like the following be reasonable,
> which explicitly lists/handles all expected tree codes, or is something
> like that not feasible?  (That's a subset of tree codes I gathered by a
> partial run of the GCC testsuite, and libgomp testsuite; not claiming
> this is complete.)

I think it would be a nice thing to have indeed.

So -- I'm inclined to approve this patch ;)

Thanks,
Richard.

> commit f28dd9618be8a26c6a75ee089f1755e4e0281106
> Author: Thomas Schwinge <thomas@codesourcery.com>
> Date:   Thu Sep 29 16:35:19 2016 +0200
>
>     Explicitly list all tree codes in gcc/tree-streamer.c:record_common_node
> ---
>  gcc/tree-streamer.c | 32 +++++++++++++++++++++++++-------
>  1 file changed, 25 insertions(+), 7 deletions(-)
>
> diff --git gcc/tree-streamer.c gcc/tree-streamer.c
> index 6ada89a..8567a81 100644
> --- gcc/tree-streamer.c
> +++ gcc/tree-streamer.c
> @@ -303,17 +303,32 @@ record_common_node (struct streamer_tree_cache_d *cache, tree node)
>       in the cache as hash value.  */
>    streamer_tree_cache_append (cache, node, cache->nodes.length ());
>
> -  if (POINTER_TYPE_P (node)
> -      || TREE_CODE (node) == ARRAY_TYPE)
> -    record_common_node (cache, TREE_TYPE (node));
> -  else if (TREE_CODE (node) == COMPLEX_TYPE)
> +  switch (TREE_CODE (node))
>      {
> +    case ERROR_MARK:
> +    case FIELD_DECL:
> +    case FIXED_POINT_TYPE:
> +    case IDENTIFIER_NODE:
> +    case INTEGER_CST:
> +    case INTEGER_TYPE:
> +    case POINTER_BOUNDS_TYPE:
> +    case REAL_TYPE:
> +    case TREE_LIST:
> +    case VOID_CST:
> +    case VOID_TYPE:
> +      /* No recursion.  */
> +      break;
> +    case POINTER_TYPE:
> +    case REFERENCE_TYPE:
> +    case ARRAY_TYPE:
> +      record_common_node (cache, TREE_TYPE (node));
> +      break;
> +    case COMPLEX_TYPE:
>        /* Verify that a complex type's component type (node_type) has been
>          handled already (and we thus don't need to recurse here).  */
>        verify_common_node_recorded (cache, TREE_TYPE (node));
> -    }
> -  else if (TREE_CODE (node) == RECORD_TYPE)
> -    {
> +      break;
> +    case RECORD_TYPE:
>        /* The FIELD_DECLs of structures should be shared, so that every
>          COMPONENT_REF uses the same tree node when referencing a field.
>          Pointer equality between FIELD_DECLs is used by the alias
> @@ -322,6 +337,9 @@ record_common_node (struct streamer_tree_cache_d *cache, tree node)
>          nonoverlapping_component_refs_of_decl_p).  */
>        for (tree f = TYPE_FIELDS (node); f; f = TREE_CHAIN (f))
>         record_common_node (cache, f);
> +      break;
> +    default:
> +      gcc_unreachable ();
>      }
>  }
>
>
>
> Grüße
>  Thomas