On Thu, 20 Jul 2017, Tom de Vries wrote:
> On 07/20/2017 12:10 PM, Richard Biener wrote:
> > On Thu, 20 Jul 2017, Tom de Vries wrote:
> >
> > > Hi,
> > >
> > > this patch fixes PR81430, an ICE in the libgomp testsuite for both openmp
> > > and
> > > openacc test-cases for x86_64 with nvptx accelerator.
> > >
> > > The scenario how we hit the ICE is as follows:
> > > - a testcase is compiled with -O2
> > > - ix86_option_optimization_table enables
> > > OPT_freorder_blocks_and_partition at -O2
> > > - cc1 writes out the flag as part of DECL_FUNCTION_SPECIFIC_OPTIMIZATION
> > > - lto1 reads in the flag as part of DECL_FUNCTION_SPECIFIC_OPTIMIZATION
> > > - lto1 uses the flag, and runs pass_partition_blocks
> > > - pass_partition_blocks ICEs, because it generates code that is not
> > > supported by the nvptx target.
> > >
> > > Note that for standalone compilation for single-thread ptx execution, we
> > > don't
> > > attempt to run pass_partition_blocks. This is because for nvptx,
> > > TARGET_HAVE_NAMED_SECTIONS is set to false, and this bit in finish_options
> > > switches off pass_partition_blocks:
> > > ...
> > > /* If the target requested unwind info, then turn off the
> > > partitioning optimization with a different message. Likewise, if
> > > the target does not support named sections. */
> > >
> > > if (opts->x_flag_reorder_blocks_and_partition
> > > && (!targetm_common.have_named_sections
> > > || (opts->x_flag_unwind_tables
> > > && targetm_common.unwind_tables_default
> > > && (ui_except == UI_SJLJ || ui_except >= UI_TARGET))))
> > > {
> > > if (opts_set->x_flag_reorder_blocks_and_partition)
> > > inform (loc,
> > > "-freorder-blocks-and-partition does not work "
> > > "on this architecture");
> > > opts->x_flag_reorder_blocks_and_partition = 0;
> > > opts->x_flag_reorder_blocks = 1;
> > > }
> > > ...
> > >
> > > The patch fixes this by calling finish_options in lto1 after
> > > cl_optimization_restore.
> > >
> > > Points for review:
> > > 1. I'm uncertain though about the placement of the call. Perhaps it should
> > > be
> > > in cl_optimization_restore, before targetm.override_options_after_change?
> > >
> > > 2. I think that this is offloading specific, so perhaps this should be
> > > guarded
> > > with lto_stream_offload_p or #ifdef ACCEL_COMPILER or some such.
> >
> > Hmm, I agree with #2. I think it conceptually is a LTO stream adjustment
> > and thus we should do this at the time we stream in the
> > optimization/target nodes (like we remap modes for example). Not
> > sure if it's possible to do this at that point, but it looks like
> > finish_options takes two option structs and thus we should be able to
> > call it.
> >
>
> With what parameters? Patch below tries with same option struct, but ...
>
> > Do you get the inform note? I suppose we don't really want that, no?
> >
>
> ... I think that way we'll get the inform note (while the previous solution
> did not).
>
> I've also tried with a tmp2 memset to 0, but that ran into problems when doing
> a maybe_set_param_value.
Use global_options_set? That should do what the other patch did.
> Thanks,
> - Tom
>
> diff --git a/gcc/tree-streamer-in.c b/gcc/tree-streamer-in.c
> index 7f7ea7f..e0e792b 100644
> --- a/gcc/tree-streamer-in.c
> +++ b/gcc/tree-streamer-in.c
> @@ -33,6 +33,7 @@ along with GCC; see the file COPYING3. If not see
> #include "ipa-chkp.h"
> #include "gomp-constants.h"
> #include "asan.h"
> +#include "opts.h"
>
>
> /* Read a STRING_CST from the string table in DATA_IN using input
> @@ -769,6 +770,20 @@ lto_input_ts_function_decl_tree_pointers (struct
> lto_input_block *ib,
> DECL_FUNCTION_SPECIFIC_TARGET (expr) = stream_read_tree (ib, data_in);
> #endif
> DECL_FUNCTION_SPECIFIC_OPTIMIZATION (expr) = stream_read_tree (ib,
> data_in);
> +#ifdef ACCEL_COMPILER
> + {
> + tree opts = DECL_FUNCTION_SPECIFIC_OPTIMIZATION (expr);
> + if (opts)
> + {
> + struct gcc_options tmp;
> + cl_optimization_restore (&tmp, TREE_OPTIMIZATION (opts));
> + finish_options (&tmp, &tmp, DECL_SOURCE_LOCATION (expr));
> + opts = build_optimization_node (&tmp);
> +
> + DECL_FUNCTION_SPECIFIC_OPTIMIZATION (expr) = opts;
> + }
> + }
> +#endif
>
> /* If the file contains a function with an EH personality set,
> then it was compiled with -fexceptions. In that case, initialize
>
>
--
Richard Biener <rguent...@suse.de>
SUSE LINUX GmbH, GF: Felix Imendoerffer, Jane Smithard, Graham Norton, HRB
21284 (AG Nuernberg)
