re PR middle-end/49310 (Compile time hog in var-tracking emit)

PR debug/49310
* var-tracking.c (loc_exp_dep, onepart_aux): New structs.
(variable_part): Replace offset with union.
(enum onepart_enum, onepart_enum_t): New.
(variable_def): Drop cur_loc_changed, add onepart.
(value_chain_def, const_value_chain): Remove.
(VAR_PART_OFFSET, VAR_LOC_1PAUX): New macros, with checking.
(VAR_LOC_DEP_LST, VAR_LOC_DEP_LSTP): New macros.
(VAR_LOC_FROM, VAR_LOC_DEPTH, VAR_LOC_DEP_VEC): Likewise.
(value_chain_pool, value_chains): Remove.
(dropped_values): New.
(struct parm_reg): Only if HAVE_window_save.
(vt_stack_adjustments): Don't record register arguments.
(dv_as_rtx): New.
(dv_onepart_p): Return a onepart_enum_t.
(onepart_pool): New.
(dv_pool): Remove.
(dv_from_rtx): New.
(variable_htab_free): Release onepart aux data.  Reset flags.
(value_chain_htab_hash, value_chain_htab_eq): Remove.
(unshare_variable): Use onepart field.  Propagate onepart aux
data or offset.  Drop cur_loc_changed.
(val_store): Cope with NULL insn.  Rephrase dump output.  Check
for unsuitable locs.  Add FIXME on using cselib locs.
(val_reset): Remove FIXME of unfounded concerns.
(val_resolve): Check for unsuitable locs.  Add FIXME on using
cselib locs.
(variable_union): Use onepart field, adjust access to offset.
(NO_LOC_P): New.
(VALUE_CHANGED, DECL_CHANGED): Update doc.
(set_dv_changed): Clear NO_LOC_P when changed.
(find_loc_in_1pdv): Use onepart field.
(intersect_loc_chains): Likewise.
(unsuitable_loc): New.
(loc_cmp): Keep ENTRY_VALUEs at the end of the loc list.
(add_value_chain, add_value_chains): Remove.
(add_cselib_value_chains, remove_value_chain): Likewise.
(remove_value_chains, remove_cselib_value_chains): Likewise.
(canonicalize_loc_order_check): Use onepart.  Drop cur_loc_changed.
(canonicalize_values_star, canonicalize_vars_star): Use onepart.
(variable_merge_over_cur): Likewise.  Adjust access to offset.
Drop cur_loc_changed.
(variable_merge_over_src): Use onepart field.
(remove_duplicate_values): Likewise.
(variable_post_merge_new_vals): Likewise.
(find_mem_expr_in_1pdv): Likewise.
(dataflow_set_preserve_mem_locs): Likewise.  Drop cur_loc_changed
and value chains.
(dataflow_set_remove_mem_locs): Likewise.  Use VAR_LOC_FROM.
(variable_different_p): Use onepart field.  Move onepart test out
of the loop.
(argument_reg_set): Drop.
(add_uses, add_stores): Preserve but do not record in dynamic
tables equivalences for ENTRY_VALUEs and CFA_based addresses.
Avoid unsuitable address expressions.
(EXPR_DEPTH): Unlimit.
(EXPR_USE_DEPTH): Repurpose PARAM_MAX_VARTRACK_EXPR_DEPTH.
(prepare_call_arguments): Use DECL_RTL_IF_SET.
(dump_var): Adjust access to offset.
(variable_from_dropped, recover_dropped_1paux): New.
(variable_was_changed): Drop cur_loc_changed.  Use onepart.
Preserve onepart aux in empty_var.  Recover empty_var and onepart
aux from dropped_values.
(find_variable_location_part): Special-case onepart.  Adjust
access to offset.
(set_slot_part): Use onepart.  Drop cur_loc_changed.  Adjust
access to offset.  Initialize onepaux.  Drop value chains.
(delete_slot_part): Drop value chains.  Use VAR_LOC_FROM.
(VEC (variable, heap), VEC (rtx, stack)): Define.
(expand_loc_callback_data): Drop dummy, cur_loc_changed,
ignore_cur_loc.  Add expanding, pending, depth.
(loc_exp_dep_alloc, loc_exp_dep_clear): New.
(loc_exp_dep_insert, loc_exp_dep_set): New.
(notify_dependents_of_resolved_value): New.
(update_depth, vt_expand_var_loc_chain): New.
(vt_expand_loc_callback): Revamped.
(resolve_expansions_pending_recursion): New.
(INIT_ELCD, FINI_ELCD): New.
(vt_expand_loc): Use the new macros above.  Drop ignore_cur_loc
parameter, adjust all callers.
(vt_expand_loc_dummy): Drop.
(vt_expand_1pvar): New.
(emit_note_insn_var_location): Operate on non-debug decls only.
Revamp multi-part cur_loc recomputation and one-part expansion.
Drop cur_loc_changed.  Adjust access to offset.
(VEC (variable, heap)): Drop.
(changed_variables_stack, changed_values_stack): Drop.
(check_changed_vars_0, check_changed_vars_1): Remove.
(check_changed_vars_2, check_changed_vars_3): Remove.
(values_to_stack, remove_value_from_changed_variables): New.
(notify_dependents_of_changed_value, process_changed_values): New.
(emit_notes_for_changes): Revamp onepart updates.
(emit_notes_for_differences_1): Use onepart.  Drop cur_loc_changed
and value chains.  Propagate onepaux.  Recover empty_var and onepaux
from dropped_values.
(emit_notes_for_differences_2): Drop value chains.
(emit_notes_in_bb): Adjust.
(vt_emit_notes): Drop value chains, changed_variables_stack.
Initialize and release dropped_values.
(create_entry_value): Revamp.
(vt_add_function_parameter): Use new interface.
(note_register_arguments): Remove.
(vt_initialize): Drop value chains and register arguments.
(vt_finalize): Drop value chains.  Release windowed_parm_regs only
if HAVE_window_save.
* rtl.h: Document various pass-local uses of RTL flags.
* tree.h (DECL_RTL_KNOWN_SET): New.
* doc/invoke.texi (param max-vartrack-expr-depth): Update
description and default.

From-SVN: r180194

1 files changed, 1 insertions, 2 deletions

diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index 4f55dbc..0ac9f39 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -9081,8 +9081,7 @@ compile time for more complete debug information.  If this is set too
 low, value expressions that are available and could be represented in
 debug information may end up not being used; setting this higher may
 enable the compiler to find more complex debug expressions, but compile
-time may grow exponentially, and even then, it may fail to find more
-usable expressions.  The default is 10.
+time and memory use may grow.  The default is 12.
 
 @item min-nondebug-insn-uid
 Use uids starting at this parameter for nondebug insns.  The range below