Re: [PATCH] Combine location with block using block_locations

[Richard Guenther <richard dot guenther at gmail dot com>]

On Mon, Sep 10, 2012 at 5:27 PM, Dehao Chen <dehao@google.com> wrote:
> On Mon, Sep 10, 2012 at 3:01 AM, Richard Guenther
> <richard.guenther@gmail.com> wrote:
>> On Sun, Sep 9, 2012 at 12:26 AM, Dehao Chen <dehao@google.com> wrote:
>>> Hi, Diego,
>>>
>>> Thanks a lot for the review. I've updated the patch.
>>>
>>> This patch is large and may easily break builds because it reserves
>>> more complete information for TREE_BLOCK as well as gimple_block (may
>>> trigger bugs that was hided when these info are unavailable). I've
>>> done more rigorous testing to ensure that most bugs are caught before
>>> checking in.
>>>
>>> * Sync to the head and retest all gcc testsuite.
>>> * Port the patch to google-4_7 branch to retest all gcc testsuite, as
>>> well as build many large applications.
>>>
>>> Through these tests, I've found two additional bugs that was omitted
>>> in the original implementation. A new patch is attached (patch.txt) to
>>> fix these problems. After this fix, all gcc testsuites pass for both
>>> trunk and google-4_7 branch. I've also copy pasted the new fixes
>>> (lto.c and tree-cfg.c) below. Now I'd say this patch is in good shape.
>>> But it may not be perfect. I'll look into build failures as soon as it
>>> arises.
>>>
>>> Richard and Diego, could you help me take a look at the following two fixes?
>>>
>>> Thanks,
>>> Dehao
>>>
>>> New fixes:
>>> --- gcc/lto/lto.c       (revision 191083)
>>> +++ gcc/lto/lto.c       (working copy)
>>> @@ -1559,8 +1559,6 @@ lto_fixup_prevailing_decls (tree t)
>>>  {
>>>    enum tree_code code = TREE_CODE (t);
>>>    LTO_NO_PREVAIL (TREE_TYPE (t));
>>> -  if (CODE_CONTAINS_STRUCT (code, TS_COMMON))
>>> -    LTO_NO_PREVAIL (TREE_CHAIN (t));
>>
>> That change is odd.  Can you show us how it breaks?
>
> This will break LTO build of gcc.c-torture/execute/pr38051.c
>
> There is data structure like:
>
>   union { long int l; char c[sizeof (long int)]; } u;
>
> Once the block info is reserved for this, it'll reserve this data
> structure. And inside this data structure, there is VAR_DECL. Thus
> LTO_NO_PREVAIL assertion does not satisfy here for TREE_CHAIN (t).

I see - the issue here is that this data structure is not reached at the time
we call free_lang_data (via find_decls_types_r).  But maybe I do not understand
"once the block info is reserved for this".

So the patch papers over an issue elsewhere I believe.  Maybe Micha can
add some clarification here though, how BLOCK_VARS should be visible
here

Richard.

>>
>>>    if (DECL_P (t))
>>>      {
>>>        LTO_NO_PREVAIL (DECL_NAME (t));
>>>
>>> Index: gcc/tree-cfg.c
>>> ===================================================================
>>> --- gcc/tree-cfg.c      (revision 191083)
>>> +++ gcc/tree-cfg.c      (working copy)
>>> @@ -5980,9 +5974,21 @@ move_stmt_op (tree *tp, int *walk_subtrees, void *
>>>    tree t = *tp;
>>>
>>>    if (EXPR_P (t))
>>> -    /* We should never have TREE_BLOCK set on non-statements.  */
>>> -    gcc_assert (!TREE_BLOCK (t));
>>> -
>>> +    {
>>> +      tree block = TREE_BLOCK (t);
>>> +      if (p->orig_block == NULL_TREE
>>> +         || block == p->orig_block
>>> +         || block == NULL_TREE)
>>> +       TREE_SET_BLOCK (t, p->new_block);
>>> +#ifdef ENABLE_CHECKING
>>> +      else if (block != p->new_block)
>>> +       {
>>> +         while (block && block != p->orig_block)
>>> +           block = BLOCK_SUPERCONTEXT (block);
>>> +         gcc_assert (block);
>>> +       }
>>> +#endif
>>
>> I think what this means is that TREE_BLOCK on non-stmts are meaningless
>> (thus only gimple_block is interesting on GIMPLE, not BLOCKs on trees).
>>
>> So instead of setting a BLOCK in some cases you should clear BLOCK
>> if it happens to be set, or alternatively, only re-set it if there was
>> a block associated
>> with it.
>
> Yeah, makes sense. New change:
>
> @@ -5980,9 +5974,10 @@
>    tree t = *tp;
>
>    if (EXPR_P (t))
> -    /* We should never have TREE_BLOCK set on non-statements.  */
> -    gcc_assert (!TREE_BLOCK (t));
> -
> +    {
> +      if (TREE_BLOCK (t))
> +       TREE_SET_BLOCK (t, p->new_block);
> +    }
>    else if (DECL_P (t) || TREE_CODE (t) == SSA_NAME)
>      {
>        if (TREE_CODE (t) == SSA_NAME)
>
> Thanks,
> Dehao
>
>>
>> Richard.
>>
>>> +    }
>>>    else if (DECL_P (t) || TREE_CODE (t) == SSA_NAME)
>>>      {
>>>        if (TREE_CODE (t) == SSA_NAME)
>>>
>>> Whole patch:
>>> gcc/ChangeLog:
>>> 2012-09-08  Dehao Chen  <dehao@google.com>
>>>
>>>         * toplev.c (general_init): Init block_locations.
>>>         * tree.c (tree_set_block): New.
>>>         (tree_block): Change to use LOCATION_BLOCK.
>>>         * tree.h (TREE_SET_BLOCK): New.
>>>         * final.c (reemit_insn_block_notes): Change to use LOCATION_BLOCK.
>>>         (final_start_function): Likewise.
>>>         * input.c (expand_location_1): Likewise.
>>>         * input.h (LOCATION_LOCUS): New.
>>>         (LOCATION_BLOCK): New.
>>>         (IS_UNKNOWN_LOCATION): New.
>>>         * fold-const.c (expr_location_or): Change to use new location.
>>>         * reorg.c (emit_delay_sequence): Likewise.
>>>         (try_merge_delay_insns): Likewise.
>>>         * modulo-sched.c (dump_insn_location): Likewise.
>>>         * lto-streamer-out.c (lto_output_location_bitpack): Likewise.
>>>         * jump.c (rtx_renumbered_equal_p): Likewise.
>>>         * ifcvt.c (noce_try_move): Likewise.
>>>         (noce_try_store_flag): Likewise.
>>>         (noce_try_store_flag_constants): Likewise.
>>>         (noce_try_addcc): Likewise.
>>>         (noce_try_store_flag_mask): Likewise.
>>>         (noce_try_cmove): Likewise.
>>>         (noce_try_cmove_arith): Likewise.
>>>         (noce_try_minmax): Likewise.
>>>         (noce_try_abs): Likewise.
>>>         (noce_try_sign_mask): Likewise.
>>>         (noce_try_bitop): Likewise.
>>>         (noce_process_if_block): Likewise.
>>>         (cond_move_process_if_block): Likewise.
>>>         (find_cond_trap): Likewise.
>>>         * dwarf2out.c (add_src_coords_attributes): Likewise.
>>>         * expr.c (expand_expr_real): Likewise.
>>>         * tree-parloops.c (create_loop_fn): Likewise.
>>>         * recog.c (peep2_attempt): Likewise.
>>>         * function.c (free_after_compilation): Likewise.
>>>         (expand_function_end): Likewise.
>>>         (set_insn_locations): Likewise.
>>>         (thread_prologue_and_epilogue_insns): Likewise.
>>>         * print-rtl.c (print_rtx): Likewise.
>>>         * profile.c (branch_prob): Likewise.
>>>         * trans-mem.c (ipa_tm_scan_irr_block): Likewise.
>>>         * gimplify.c (gimplify_call_expr): Likewise.
>>>         * except.c (duplicate_eh_regions_1): Likewise.
>>>         * emit-rtl.c (try_split): Likewise.
>>>         (make_insn_raw): Likewise.
>>>         (make_debug_insn_raw): Likewise.
>>>         (make_jump_insn_raw): Likewise.
>>>         (make_call_insn_raw): Likewise.
>>>         (emit_pattern_after_setloc): Likewise.
>>>         (emit_pattern_after): Likewise.
>>>         (emit_debug_insn_after): Likewise.
>>>         (emit_pattern_before): Likewise.
>>>         (emit_insn_before_setloc): Likewise.
>>>         (emit_jump_insn_before): Likewise.
>>>         (emit_call_insn_before_setloc): Likewise.
>>>         (emit_call_insn_before): Likeise.
>>>         (emit_debug_insn_before_setloc): Likewise.
>>>         (emit_copy_of_insn_after): Likewise.
>>>         (insn_locators_alloc): Remove.
>>>         (insn_locators_finalize): Remove.
>>>         (insn_locators_free): Remove.
>>>         (set_curr_insn_source_location): Remove.
>>>         (get_curr_insn_source_location): Remove.
>>>         (set_curr_insn_block): Remove.
>>>         (get_curr_insn_block): Remove.
>>>         (locator_scope): Remove.
>>>         (insn_scope): Change to use new location.
>>>         (locator_location): Remove.
>>>         (insn_line): Change to use new location.
>>>         (locator_file): Remove.
>>>         (insn_file): Change to use new location.
>>>         (locator_eq): Remove.
>>>         (insn_locations_init): New.
>>>         (insn_locations_finalize): New.
>>>         (set_curr_insn_location): New.
>>>         (curr_insn_location): New.
>>>         * cfgexpand.c (gimple_assign_rhs_to_tree): Change to use new location.
>>>         (expand_gimple_cond): Likewise.
>>>         (expand_call_stmt): Likewise.
>>>         (expand_gimple_stmt_1): Likewise.
>>>         (expand_gimple_basic_block): Likewise.
>>>         (construct_exit_block): Likewise.
>>>         (gimple_expand_cfg): Likewise.
>>>         * cfgcleanup.c (try_forward_edges): Likewise.
>>>         * tree-ssa-live.c (remove_unused_scope_block_p): Likewise.
>>>         (dump_scope_block): Likewise.
>>>         (remove_unused_locals): Likewise.
>>>         * rtl.c (rtx_equal_p_cb): Likewise.
>>>         (rtx_equal_p): Likewise.
>>>         * rtl.h (XUINT): New.
>>>         (INSN_LOCATOR): Remove.
>>>         (CURR_INSN_LOCATION): Remove.
>>>         (INSN_LOCATION): New.
>>>         (INSN_HAS_LOCATION): New.
>>>         * tree-inline.c (remap_gimple_op_r): Change to use new location.
>>>         (copy_tree_body_r): Likewise.
>>>         (copy_phis_for_bb): Likewise.
>>>         (expand_call_inline): Likewise.
>>>         * tree-streamer-in.c (lto_input_ts_exp_tree_pointers): Likewise.
>>>         * tree-streamer-out.c (write_ts_decl_minimal_tree_pointers): Likewise.
>>>         * gimple-streamer-out.c (output_gimple_stmt): Likewise.
>>>         * combine.c (try_combine): Likewise.
>>>         * tree-outof-ssa.c (set_location_for_edge): Likewise.
>>>         (insert_partition_copy_on_edge): Likewise.
>>>         (insert_value_copy_on_edge): Likewise.
>>>         (insert_rtx_to_part_on_edge): Likewise.
>>>         (insert_part_to_rtx_on_edge): Likewise.
>>>         * basic-block.h (edge_def): Remove field.
>>>         * gimple.h (gimple_statement_base): Remove field.
>>>         (gimple_bb): Change to use new location.
>>>         (gimple_set_block): Likewise.
>>>         (gimple_has_location): Likewise.
>>>         * tree-cfg.c (make_cond_expr_edges): Likewise.
>>>         (make_goto_expr_edges): Likewise.
>>>         (gimple_can_merge_blocks_p): Likewise.
>>>         (move_stmt_op): Likewise.
>>>         (move_block_to_fn): Likewise.
>>>         * config/alpha/alpha.c (alpha_output_mi_thunk_osf): Likewise.
>>>         * config/sparc/sparc.c (sparc_output_mi_thunk): Likewise.
>>>         * config/i386/i386.c (x86_output_mi_thunk): Likewise.
>>>         * config/tilegx/tilegx.c (tilegx_output_mi_thunk): Likewise.
>>>         * config/sh/sh.c (sh_output_mi_thunk): Likewise.
>>>         * config/ia64/ia64.c (ia64_output_mi_thunk): Likewise.
>>>         * config/rs6000/rs6000.c (rs6000_output_mi_thunk): Likewise.
>>>         * config/score/score.c (score_output_mi_thunk): Likewise.
>>>         * config/tilepro/tilepro.c (tilepro_asm_output_mi_thunk): Likewise.
>>>         * config/mips/mips.c (mips_output_mi_thunk): Likewise.
>>>         * cfgrtl.c (unique_locus_on_edge_between_p): Likewise.
>>>         (unique_locus_on_edge_between_p): Likewise.
>>>         (emit_nop_for_unique_locus_between): Likewise.
>>>         (force_nonfallthru_and_redirect): Likewise.
>>>         (fixup_reorder_chain): Likewise.
>>>         (cfg_layout_merge_blocks): Likewise.
>>>         * stmt.c (emit_case_nodes): Likewise.
>>>
>>> gcc/lto/ChangeLog:
>>> 2012-09-08  Dehao Chen  <dehao@google.com>
>>>
>>>         * lto/lto.c (lto_fixup_prevailing_decls): Remove tree.exp.block field.
>>>
>>> libcpp/ChangeLog:
>>> 2012-09-08  Dehao Chen  <dehao@google.com>
>>>
>>>         * include/line-map.h (MAX_SOURCE_LOCATION): New value.
>>>         (location_adhoc_data_init): New.
>>>         (location_adhoc_data_fini): New.
>>>         (get_combined_adhoc_loc): New.
>>>         (get_data_from_adhoc_loc): New.
>>>         (get_location_from_adhoc_loc): New.
>>>         (COMBINE_LOCATION_DATA): New.
>>>         (IS_ADHOC_LOC): New.
>>>         (expanded_location): New field.
>>>         * line-map.c (location_adhoc_data): New.
>>>         (location_adhoc_data_htab): New.
>>>         (curr_adhoc_loc): New.
>>>         (location_adhoc_data): New.
>>>         (allocated_location_adhoc_data): New.
>>>         (location_adhoc_data_hash): New.
>>>         (location_adhoc_data_eq): New.
>>>         (location_adhoc_data_update): New.
>>>         (get_combined_adhoc_loc): New.
>>>         (get_data_from_adhoc_loc): New.
>>>         (get_location_from_adhoc_loc): New.
>>>         (location_adhoc_data_init): New.
>>>         (location_adhoc_data_fini): New.
>>>         (linemap_lookup): Change to use new location.
>>>         (linemap_ordinary_map_lookup): Likewise.
>>>         (linemap_macro_map_lookup): Likewise.
>>>         (linemap_macro_map_loc_to_def_point): Likewise.
>>>         (linemap_macro_map_loc_unwind_toward_spel): Likewise.
>>>         (linemap_get_expansion_line): Likewise.
>>>         (linemap_get_expansion_filename): Likewise.
>>>         (linemap_location_in_system_header_p): Likewise.
>>>         (linemap_location_from_macro_expansion_p): Likewise.
>>>         (linemap_macro_loc_to_spelling_point): Likewise.
>>>         (linemap_macro_loc_to_def_point): Likewise.
>>>         (linemap_macro_loc_to_exp_point): Likewise.
>>>         (linemap_resolve_location): Likewise.
>>>         (linemap_unwind_toward_expansion): Likewise.
>>>         (linemap_unwind_to_first_non_reserved_loc): Likewise.
>>>         (linemap_expand_location): Likewise.
>>>         (linemap_dump_location): Likewise.