Bug 13146

Summary: inheritance for nonoverlapping_component_refs_p
Product: gcc Reporter: Dan Nicolaescu <dann>
Component: middle-endAssignee: Richard Biener <rguenth>
Status: RESOLVED FIXED    
Severity: enhancement CC: gcc-bugs, giovannibajo, rguenth, rth
Priority: P2 Keywords: alias, missed-optimization, patch
Version: 3.4.0   
Target Milestone: 4.5.0   
URL: http://gcc.gnu.org/ml/gcc-patches/2002-05/msg01996.html
Host: Target:
Build: Known to work:
Known to fail: Last reconfirmed: 2008-03-15 12:40:51

Description Dan Nicolaescu 2003-11-20 22:24:28 UTC 
Currently g++ cannot tell that accesses to class members from different points
of the inheritance hierachy cannot overlap. 

There is a patch that fixes the problem at:

http://gcc.gnu.org/ml/gcc-patches/2002-05/msg01996.html

but it seems that has been forgotten. This bug was created so that the issue 
is not completely forgotten.

A testcase is below. It would be nice if a C++ specialist would 
add more tests.

/* { dg-do link } */

class first
{
public:
  double d;
  int f1;
};

class middle : public first
{
};

class second : public middle
{
public:
  int f2;
  short a;
};

class third
{
public:
  char a;
  char b;
};

class multi: public third, public second
{
public:
  short s;
  char f3;
};

extern void link_error ();

void
foo (first *s1, second *s2)
{
  s1->f1 = 0;
  s2->f2 = 0;
  s1->f1++;
  s2->f2++;
  s1->f1++;
  s2->f2++;
  if (s1->f1 != 2)
    link_error ();
}

void
bar (first *s1, multi *s3)
{
  s1->f1 = 0;
  s3->f3 = 0;
  s1->f1++;
  s3->f3++;
  s1->f1++;
  s3->f3++;
  if (s1->f1 != 2)
    link_error ();
}


int
main()
{
  first a;
  second b;
  multi c;
  foo (&a, &b);
  bar (&a, &c);
  return 0;
}
Comment 1 Andrew Pinski 2003-11-25 01:00:51 UTC 
Confirmed.
Comment 2 Andrew Pinski 2003-12-26 02:30:12 UTC 
There was a recent discussion about this.
Comment 3 Dara Hazeghi 2004-01-19 21:28:20 UTC 
Would anybody like to volunteer to check Richard's patch?
Comment 4 Giovanni Bajo 2004-07-03 02:37:23 UTC 
RTH: I think your patch linked here is not good anymore. Or at least, we want 
this done on the tree level rather than RTL. Is this still an aliasing bug? If 
so, maybe Diego will be willing to have a look at it.
Comment 5 Diego Novillo 2004-10-28 20:23:50 UTC 
The tree alias analyzer depends on the type information given to it by alias.c.
 In this case, the types of the pointers passed to the two routines have
conflicting alias sets, so they are given the same memory tag.

Without context sensitive information, we cannot tell where these arguments are
really pointing to, so we have to base the analysis exclusively on types. 
Notice, however, that the analysis DTRT when the calls are inlined.
Comment 6 Andrew Pinski 2005-01-27 02:17:42 UTC 
Also it sounds like the scheduler still needs support from the rtl aliasing mechanism is helped by more 
information.
Comment 7 Richard Biener 2008-03-14 20:30:05 UTC 
The testcase is fixed by the SCCVN alias-oracle patch.  I don't see how
BINFOs should be needed here - if the MEM_REFs are still there the
disambiguation can happen based on the member offsets, no?
Comment 8 Dan Nicolaescu 2008-03-15 00:28:54 UTC 
(In reply to comment #7)
> The testcase is fixed by the SCCVN alias-oracle patch.

Are you sure? I still see the problem (.final_cleanup dump):

void bar(first*, multi*) (s1, s3)
{
<bb 2>:
  s1->f1 = 0;
  s3->f3 = 0;
  s1->f1 = s1->f1 + 1;
  s3->f3 = s3->f3 + 1;
  s1->f1 = s1->f1 + 1;
  s3->f3 = s3->f3 + 1;
  if (s1->f1 != 2)
    goto <bb 3>;
  else
    goto <bb 4>;
<bb 3>:
  link_error () [tail call];
<bb 4>:
  return;
}
void foo(first*, second*) (s1, s2)
{
<bb 2>:
  s1->f1 = 0;
  s2->f2 = 0;
  s1->f1 = s1->f1 + 1;
  s2->f2 = s2->f2 + 1;
  s1->f1 = s1->f1 + 1;
  s2->f2 = s2->f2 + 1;
  if (s1->f1 != 2)
    goto <bb 3>;
  else
    goto <bb 4>;
<bb 3>:
  link_error () [tail call];
<bb 4>:
  return;
}
Comment 9 Richard Biener 2008-03-15 12:28:37 UTC 
Ah, indeed.  It was fixed by the patch for PR23094 that I had applied ;)
Maybe adjust this testcase to not be a dup of PR23094.
Comment 10 Richard Biener 2008-03-15 12:40:51 UTC 
the nonoverlapping_memrefs_p check can be simplified (consolidated) by using
the generic get_ref_base_and_extent code.  The result of that can be adjusted
by MEM_OFFSET and only in case of an indirect base we may try to
disambiguate based on struct contain-ness of the types of that accesses.

Maybe I'll have a look, as this sounds uselful in general.
Comment 11 Richard Biener 2008-05-16 11:12:52 UTC 
C testcase:

struct A {
  int i;
};
struct B {
  struct A a;
  int j;
};

int foo (struct A *p, struct B *q)
{
  p->i = 0;
  q->j = 1;
  return p->i;
}

we should optimize this to return zero.

The reasoning is that while p may access a part of *q we still can tell
that q->j is not in that part.  Thus for offset based disambiguation with
two pointers we can in some cases find a common base.
Comment 12 Richard Biener 2009-01-17 12:58:51 UTC 
Note that we have to be very careful here because

struct X {
  int i;
};
struct A {
  int i;
};
struct B {
  struct A a;
  int j;
};

int foo (struct X *p, struct B *q)
{
  p->i = 0;
  q->a.i = 1;
  return p->i;
}

may be aliasing.  One need to consult the C standard and defect reports again
for the "common initial sequence" in structs stuff.
Comment 13 Richard Biener 2009-01-17 16:03:00 UTC 
Subject: Bug 13146

Author: rguenth
Date: Sat Jan 17 16:02:36 2009
New Revision: 143469

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=143469
Log:
2009-01-17  Richard Guenther  <rguenther@suse.de>

	PR middle-end/13146
	PR tree-optimization/38895
	* tree-ssa-alias.c (same_type_for_tbaa): New helper function.
	(refs_may_alias_p): Use it.  Extend access path based disambiguation.

	* gcc.dg/tree-ssa/pr13146.c: New testcase.
	* gcc.dg/tree-ssa/pr38895.c: Likewise.
	* g++.dg/tree-ssa/pr13146.C: Likewise.

Added:
    branches/alias-improvements/gcc/testsuite/g++.dg/tree-ssa/pr13146.C
    branches/alias-improvements/gcc/testsuite/gcc.dg/tree-ssa/pr13146.c
    branches/alias-improvements/gcc/testsuite/gcc.dg/tree-ssa/pr38895.c
Modified:
    branches/alias-improvements/gcc/ChangeLog.alias
    branches/alias-improvements/gcc/tree-ssa-alias.c
Comment 14 Richard Biener 2009-04-03 10:26:15 UTC 
Subject: Bug 13146

Author: rguenth
Date: Fri Apr  3 10:24:28 2009
New Revision: 145494

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=145494
Log:
2009-04-03  Richard Guenther  <rguenther@suse.de>

	PR middle-end/13146
	PR tree-optimization/23940
	PR tree-optimization/33237
	PR middle-end/33974
	PR middle-end/34093
	PR tree-optimization/36201
	PR tree-optimization/36230
	PR tree-optimization/38049
	PR tree-optimization/38207
	PR tree-optimization/38230
	PR tree-optimization/38301
	PR tree-optimization/38585
	PR middle-end/38895
	PR tree-optimization/38985
	PR tree-optimization/39299
	* tree-ssa-structalias.h: Remove.
	* tree-ssa-operands.h (NULL_USE_OPERAND_P): Make of type use_operand_p.
	(NULL_DEF_OPERAND_P): Make of type def_operand_p.
	(struct vuse_element_d): Remove.
	(struct vuse_vec_d): Likewise.
	(VUSE_VECT_NUM_ELEM, VUSE_VECT_ELEMENT_NC, VUSE_ELEMENT_PTR_NC,
	VUSE_ELEMENT_VAR_NC, VUSE_VECT_ELEMENT, VUSE_ELEMENT_PTR,
	SET_VUSE_VECT_ELEMENT, SET_VUSE_ELEMENT_VAR, SET_VUSE_ELEMENT_PTR,
	VUSE_ELEMENT_VAR): Likewise.
	(struct voptype_d): Likewise.
	(NUM_VOP_FREE_BUCKETS): Likewise.
	(struct ssa_operands): Remove vop_free_buckets and mpt_table fields.
	(struct stmt_operands_d): Remove.
	(VUSE_OP_PTR, VUSE_OP, SET_VUSE_OP, VUSE_NUM, VUSE_VECT,
	VDEF_RESULT_PTR, VDEF_RESULT, VDEF_OP_PTR, VDEF_OP, SET_VDEF_OP,
	VDEF_NUM, VDEF_VECT): Likewise.
	(copy_virtual_operands): Remove.
	(operand_build_cmp): Likewise.
	(create_ssa_artificial_load_stmt): Likewise.
	(enum ssa_op_iter_type): Remove ssa_op_iter_vdef.
	(struct ssa_operand_iterator_d): Remove vuses, vdefs, mayusesm
	vuse_index and mayuse_index members.  Pack and move done and iter_type
	members to the front.
	(SSA_OP_VMAYUSE): Remove.
	(SSA_OP_VIRTUAL_USES): Adjust.
	(FOR_EACH_SSA_VDEF_OPERAND): Remove.
	(unlink_stmt_vdef): Declare.
	(add_to_addressable_set): Remove.
	* tree-vrp.c (stmt_interesting_for_vrp): Adjust.
	(vrp_visit_stmt): Likewise.
	* doc/tree-ssa.texi (Alias analysis): Update.
	* doc/invoke.texi (max-aliased-vops): Remove docs.
	(avg-aliased-vops): Likewise.
	* tree-into-ssa.c (syms_to_rename): Remove.
	(need_to_update_vops_p): Likewise.
	(need_to_initialize_update_ssa_p): Rename to ...
	(update_ssa_initialized_fn): ... this.  Track function we are
	initialized for.
	(symbol_marked_for_renaming): Simplify.
	(add_new_name_mapping): Do not set need_to_update_vops_p.
	(dump_currdefs): Use SYMS_TO_RENAME.
	(rewrite_update_stmt): Always walk all uses/defs.
	(dump_update_ssa): Adjust.
	(init_update_ssa): Take function argument.  Track what we are
	initialized for.
	(delete_update_ssa): Reset SYMS_TO_RENAME and update_ssa_initialized_fn.
	(create_new_def_for): Initialize for cfun, assert we are initialized
	for cfun.
	(mark_sym_for_renaming): Simplify.
	(mark_set_for_renaming): Do not initialize update-ssa.
	(need_ssa_update_p): Simplify.  Take function argument.
	(name_mappings_registered_p): Assert we ask for the correct function.
	(name_registered_for_update_p): Likewise.
	(ssa_names_to_replace): Likewise.
	(release_ssa_name_after_update_ssa): Likewise.
	(update_ssa): Likewise.  Use SYMS_TO_RENAME.
	(dump_decl_set): Do not print a newline.
	(debug_decl_set): Do it here.
	(dump_update_ssa): And here.
	* tree-ssa-loop-im.c (move_computations): Adjust.
	(movement_possibility): Likewise.
	(determine_max_movement): Likewise.
	(gather_mem_refs_stmt): Likewise.
	* tree-dump.c (dequeue_and_dump): Do not handle SYMBOL_MEMORY_TAG
	or NAME_MEMORY_TAG.
	* tree-complex.c (update_all_vops): Remove.
	(expand_complex_move): Adjust.
	* tree-ssa-loop-niter.c (chain_of_csts_start): Use NULL_TREE.
	Simplify test for memory referencing statement.  Exclude
	non-invariant ADDR_EXPRs.
	* tree-pretty-print.c (dump_generic_node): Do not handle memory tags.
	* tree-loop-distribution.c (generate_memset_zero): Adjust.
	(rdg_flag_uses): Likewise.
	* tree-tailcall.c (suitable_for_tail_opt_p): Remove memory-tag
	related code.
	(tree_optimize_tail_calls_1): Also split the
	edge from the entry block if we have degenerate PHI nodes in
	the first basic block.
	* tree.c (init_ttree): Remove memory-tag related code.
	(tree_code_size): Likewise.
	(tree_node_structure): Likewise.
	(build7_stat): Re-write to be build6_stat.
	* tree.h (MTAG_P, TREE_MEMORY_TAG_CHECK, TMR_TAG): Remove.
	(SSA_VAR_P): Adjust.
	(struct tree_memory_tag): Remove.
	(struct tree_memory_partition_tag): Likewise.
	(union tree_node): Adjust.
	(build7): Re-write to be build6.
	* tree-pass.h (pass_reset_cc_flags): Remove.
	(TODO_update_address_taken): New flag.
	(pass_simple_dse): Remove.
	* ipa-cp.c (ipcp_update_callgraph): Update SSA form.
	* params.h (MAX_ALIASED_VOPS): Remove.
	(AVG_ALIASED_VOPS): Likewise.
	* omp-low.c (expand_omp_taskreg): Update SSA form.
	* tree-ssa-dse.c (dse_optimize_stmt): Properly query if the rhs
	aliases the lhs in a copy stmt.
	* tree-ssa-dse.c (struct address_walk_data): Remove.
	(memory_ssa_name_same): Likewise.
	(memory_address_same): Likewise.
	(get_kill_of_stmt_lhs): Likewise.
	(dse_possible_dead_store_p): Simplify, use the oracle.  Handle
	unused stores.  Look through PHI nodes into post-dominated regions.
	(dse_optimize_stmt): Simplify.  Properly remove stores.
	(tree_ssa_dse): Compute dominators.
	(execute_simple_dse): Remove.
	(pass_simple_dse): Likewise.
	* ipa-reference.c (scan_stmt_for_static_refs): Open-code
	gimple_loaded_syms and gimple_stored_syms computation.
	* toplev.c (dump_memory_report): Dump alias and pta stats.
	* tree-ssa-sccvn.c (vn_reference_compute_hash): Simplify.
	(vn_reference_eq): Likewise.
	(vuses_to_vec, copy_vuses_from_stmt, vdefs_to_vec,
	copy_vdefs_from_stmt, shared_lookup_vops, shared_vuses_from_stmt,
	valueize_vuses): Remove.
	(get_def_ref_stmt_vuses): Simplify.  Rename to ...
	(get_def_ref_stmt_vuse): ... this.
	(vn_reference_lookup_2): New function.
	(vn_reference_lookup_pieces): Use walk_non_aliased_vuses for
	walking equivalent vuses.  Simplify.
	(vn_reference_lookup): Likewise.
	(vn_reference_insert): Likewise.
	(vn_reference_insert_pieces): Likewise.
	(visit_reference_op_call): Simplify.
	(visit_reference_op_load): Likewise.
	(visit_reference_op_store): Likewise.
	(init_scc_vn): Remove shared_lookup_vuses initialization.
	(free_scc_vn): Remove shared_lookup_vuses freeing.
	(sort_vuses, sort_vuses_heap): Remove.
	(get_ref_from_reference_ops): Export.
	* tree-ssa-sccvn.h (struct vn_reference_s): Replace vuses
	vector with single vuse pointer.
	(vn_reference_lookup_pieces, vn_reference_lookup,
	vn_reference_insert, vn_reference_insert_pieces): Adjust prototypes.
	(shared_vuses_from_stmt): Remove.
	(get_ref_from_reference_ops): Declare.
	* tree-ssa-loop-manip.c (slpeel_can_duplicate_loop_p): Adjust.
	* tree-ssa-copyrename.c (copy_rename_partition_coalesce): Remove
	memory-tag related code.
	* tree-ssa-ccp.c (get_symbol_constant_value): Remove memory-tag code.
	(likely_value): Add comment, skip static-chain of call statements.
	(surely_varying_stmt_p): Adjust.
	(gimplify_and_update_call_from_tree): Likewise.
	(execute_fold_all_builtins): Do not rebuild alias info.
	(gimplify_and_update_call_from_tree): Properly update VOPs.
	* tree-ssa-loop-ivopts.c (get_ref_tag): Remove.
	(copy_ref_info): Remove memory-tag related code.
	* tree-call-cdce.c (tree_call_cdce): Rename the VOP.
	* ipa-pure-const.c (check_decl): Remove memory-tag related code.
	(check_stmt): Open-code gimple_loaded_syms and gimple_stored_syms
	computation.
	* tree-ssa-dom.c (gimple_p): Remove typedef.
	(eliminate_redundant_computations): Adjust.
	(record_equivalences_from_stmt): Likewise.
	(avail_expr_hash): Likewise.
	(avail_expr_eq): Likewise.
	* tree-ssa-propagate.c (update_call_from_tree): Properly
	update VOPs.
	(stmt_makes_single_load): Likewise.
	(stmt_makes_single_store): Likewise.
	* tree-ssa-alias.c: Rewrite completely.
	(debug_memory_partitions, dump_mem_ref_stats, debug_mem_ref_stats,
	debug_mem_sym_stats, dump_mem_sym_stats_for_var,
	debug_all_mem_sym_stats, debug_mp_info, update_mem_sym_stats_from_stmt,
	delete_mem_ref_stats, create_tag_raw, dump_points_to_info,
	dump_may_aliases_for, debug_may_aliases_for, new_type_alias):
	Remove public functions.
	(pass_reset_cc_flags): Remove.
	(pass_build_alias): Move ...
	* tree-ssa-structalias.c (pass_build_alias): ... here.
	* tree-ssa-alias.c (may_be_aliased): Move ...
	* tree-flow-inline.h (may_be_aliased): ... here.
	tree-ssa-alias.c (struct count_ptr_d, count_ptr_derefs,
	count_uses_and_derefs): Move ...
	* gimple.c: ... here.
	* gimple.h (count_uses_and_derefs): Declare.
	* tree-ssa-alias.c (dump_alias_stats, ptr_deref_may_alias_global_p,
	ptr_deref_may_alias_decl_p, ptr_derefs_may_alias_p,
	same_type_for_tbaa, nonaliasing_component_refs_p, decl_refs_may_alias_p,
	indirect_ref_may_alias_decl_p, indirect_refs_may_alias_p,
	ref_maybe_used_by_call_p, ref_maybe_used_by_stmt_p,
	call_may_clobber_ref_p, stmt_may_clobber_ref_p, maybe_skip_until,
	get_continuation_for_phi, walk_non_aliased_vuses, walk_aliased_vdefs):
	New functions.
	* tree-dfa.c (refs_may_alias_p): Move ...
	* tree-ssa-alias.c (refs_may_alias_p): ... here.  Extend.
	* tree-ssa-alias.h: New file.
	* tree-ssa-sink.c (is_hidden_global_store): Adjust.
	(statement_sink_location): Likewise.
	* opts.c (decode_options): Do not adjust max-aliased-vops or
	avg-aliased-vops values.
	* timevar.def (TV_TREE_MAY_ALIAS): Remove.
	(TV_CALL_CLOBBER): Likewise.
	(TV_FLOW_SENSITIVE): Likewise.
	(TV_FLOW_INSENSITIVE): Likewise.
	(TV_MEMORY_PARTITIONING): Likewise.
	(TV_ALIAS_STMT_WALK): New timevar.
	* tree-ssa-loop-ivcanon.c (empty_loop_p): Adjust.
	* tree-ssa-address.c (create_mem_ref_raw): Use build6.
	(get_address_description): Remove memory-tag related code.
	* tree-ssa-ifcombine.c (bb_no_side_effects_p): Adjust.
	* treestruct.def (TS_MEMORY_TAG, TS_MEMORY_PARTITION_TAG): Remove.
	* tree-eh.c (cleanup_empty_eh): Do not leave stale SSA_NAMEs
	and immediate uses in statements.  Document.
	* gimple-pretty-print.c (dump_gimple_mem_ops): Adjust.
	(dump_symbols): Remove.
	(dump_gimple_mem_ops): Do not dump loaded or stored syms.
	* alias.c (get_deref_alias_set): New function split out from ...
	(get_alias_set): ... here.
	* alias.h (get_deref_alias_set): Declare.
	* tree-vect-data-refs.c (vect_create_data_ref_ptr): Remove unused
	type parameter.  Remove restrict pointer handling.  Create a
	ref-all pointer in case type-based alias sets do not conflict.
	(vect_analyze_data_refs): Remove SMT related code.
	* tree-vect-stmts.c (vectorizable_store): Re-instantiate TBAA assert.
	(vectorizable_load): Likewise.
	* tree-data-ref.h (struct dr_alias): Remove symbol_tag field.
	(DR_SYMBOL_TAG, DR_VOPS): Remove.
	* tree-data-ref.c (dr_may_alias_p): Use the alias-oracle.
	Ignore vops and SMTs.
	(dr_analyze_alias): Likewise..
	(free_data_ref): Likewise.
	(create_data_ref): Likewise.
	(analyze_all_data_dependences): Likewise.
	(get_references_in_stmt): Adjust.
	* tree-flow-inline.h (gimple_aliases_computed_p,
	gimple_addressable_vars, gimple_call_clobbered_vars,
	gimple_call_used_vars, gimple_global_var, may_aliases, memory_partition,
	factoring_name_p, mark_call_clobbered, clear_call_clobbered,
	compare_ssa_operands_equal, symbol_mem_tag, set_symbol_mem_tag,
	gimple_mem_ref_stats): Remove.
	(gimple_vop): New function.
	(op_iter_next_use): Remove vuses and mayuses cases.
	(op_iter_next_def): Remove vdefs case.
	(op_iter_next_tree): Remove vuses, mayuses and vdefs cases.
	(clear_and_done_ssa_iter): Do not set removed fields.
	(op_iter_init): Likewise.  Skip vuse and/or vdef if requested.
	Assert we are not iterating over vuses or vdefs if not also
	iterating over uses or defs.
	(op_iter_init_use): Likewise.
	(op_iter_init_def): Likewise.
	(op_iter_next_vdef): Remove.
	(op_iter_next_mustdef): Likewise.
	(op_iter_init_vdef): Likewise.
	(compare_ssa_operands_equal): Likewise.
	(link_use_stmts_after): Handle vuse operand.
	(is_call_used): Use is_call_clobbered.
	(is_call_clobbered): Global variables are always call clobbered,
	query the call-clobbers bitmap.
	(mark_call_clobbered): Ignore global variables.
	(clear_call_clobbered): Likewise.
	* tree-ssa-coalesce.c (create_outofssa_var_map): Adjust
	virtual operands sanity check.
	* tree.def (NAME_MEMORY_TAG, SYMBOL_MEMORY_TAG, MEMORY_PARTITION_TAG):
	Remove.
	(TARGET_MEM_REF): Remove TMR_TAG operand.
	* tree-dfa.c (add_referenced_var): Initialize call-clobber state.
	Remove call-clobber related code.
	(remove_referenced_var): Likewise.  Do not clear mpt or symbol_mem_tag.
	(dump_variable): Do not dump SMTs, memory stats, may-aliases or
	partitions or escape reason.
	(get_single_def_stmt, get_single_def_stmt_from_phi,
	get_single_def_stmt_with_phi): Remove.
	(dump_referenced_vars): Tidy.
	(get_ref_base_and_extent): Allow bare decls.
	(collect_dfa_stats): Adjust.
	* graphite.c (rename_variables_in_stmt): Adjust.
	(graphite_copy_stmts_from_block): Likewise.
	(translate_clast): Likewise.
	* tree-ssa-pre.c (struct bb_bitmap_sets): Add expr_dies bitmap.
	(EXPR_DIES): New.
	(translate_vuse_through_block): Use the oracle.
	(phi_translate_1): Adjust.
	(value_dies_in_block_x): Use the oracle.  Cache the outcome
	in EXPR_DIES.
	(valid_in_sets): Check if the VUSE for
	a REFERENCE is available.
	(eliminate): Do not remove stmts during elimination,
	instead queue and remove them afterwards.
	(do_pre): Do not rebuild alias info.
	(pass_pre): Run TODO_rebuild_alias before PRE.
	* tree-ssa-live.c (remove_unused_locals): Remove memory-tag code.
	* tree-sra.c (sra_walk_function): Use gimple_references_memory_p.
	(mark_all_v_defs_stmt): Remove.
	(mark_all_v_defs_seq): Adjust.
	(sra_replace): Likewise.
	(scalarize_use): Likewise.
	(scalarize_copy): Likewise.
	(scalarize_init): Likewise.
	(scalarize_ldst): Likewise.
	(todoflags): Remove.
	(tree_sra): Do not rebuild alias info.
	(tree_sra_early): Adjust.
	(pass_sra): Run TODO_update_address_taken before SRA.
	* tree-predcom.c (set_alias_info): Remove.
	(prepare_initializers_chain): Do not call it.
	(mark_virtual_ops_for_renaming): Adjust.
	(mark_virtual_ops_for_renaming_list): Remove.
	(initialize_root_vars): Adjust.
	(initialize_root_vars_lm): Likewise.
	(prepare_initializers_chain): Likewise.
	* tree-ssa-copy.c (may_propagate_copy): Remove memory-tag related code.
	(may_propagate_copy_into_stmt): Likewise.
	(merge_alias_info): Do nothing for now.
	(propagate_tree_value_into_stmt): Adjust.
	(stmt_may_generate_copy): Likewise.
	* tree-ssa-forwprop.c (tidy_after_forward_propagate_addr): Do
	not mark symbols for renaming.
	(forward_propagate_addr_expr): Match up push/pop_stmt_changes
	with the same statement, make sure to update the new pointed-to one.
	* tree-ssa-dce.c (eliminate_unnecessary_stmts): Do not copy
	call statements, do not mark symbols for renaming.
	(mark_operand_necessary): Dump something.
	(ref_may_be_aliased): New function.
	(mark_aliased_reaching_defs_necessary_1): New helper function.
	(mark_aliased_reaching_defs_necessary): Likewise.
	(mark_all_reaching_defs_necessary_1): Likewise.
	(mark_all_reaching_defs_necessary): Likewise.
	(propagate_necessity): Do not process virtual PHIs.  For
	non-aliased loads mark all reaching definitions as necessary.
	For aliased loads and stores mark the immediate dominating
	aliased clobbers as necessary.
	(visited): New global static.
	(perform_tree_ssa_dce): Free visited bitmap after propagating
	necessity.
	(remove_dead_phis): Perform simple dead virtual PHI removal.
	(remove_dead_stmt): Properly unlink virtual operands when
	removing stores.
	(eliminate_unnecessary_stmts): Schedule PHI removal after
	stmt removal.
	* tree-ssa-ter.c (is_replaceable_p): Adjust.
	(process_replaceable): Likewise.
	(find_replaceable_in_bb): Likewise.
	* tree-ssa.c (verify_ssa_name): Verify all VOPs are
	based on the single gimple vop.
	(verify_flow_insensitive_alias_info): Remove.
	(verify_flow_sensitive_alias_info): Likewise.
	(verify_call_clobbering): Likewise.
	(verify_memory_partitions): Likewise.
	(verify_alias_info): Likewise.
	(verify_ssa): Adjust..
	(execute_update_addresses_taken): Export.  Update SSA
	manually.  Optimize only when optimizing.  Use a local bitmap.
	(pass_update_address_taken): Remove TODO_update_ssa, add
	TODO_dump_func.
	(pass_update_address_taken): Just use TODO_update_address_taken.
	(init_tree_ssa): Do not initialize addressable_vars.
	(verify_ssa): Verify new VUSE / VDEF properties.
	Verify that all stmts definitions have the stmt as SSA_NAME_DEF_STMT.
	Do not call verify_alias_info.
	(delete_tree_ssa): Clear the VUSE, VDEF operands.
	Do not free the loaded and stored syms bitmaps.  Reset the escaped
	and callused solutions.  Do not free addressable_vars.
	Remove memory-tag related code.
	(warn_uninitialized_var): Aliases are always available.
	* tree-ssa-loop-prefetch.c (gather_memory_references): Adjust.
	* lambda-code.c (can_put_in_inner_loop): Adjust.
	(can_put_after_inner_loop): Likewise.
	(perfect_nestify): Likewise.
	* tree-vect-stmts.c (vect_stmt_relevant_p): Adjust.
	(vect_gen_widened_results_half): Remove CALL_EXPR handling.
	(vectorizable_conversion): Do not mark symbols for renaming.
	* tree-inline.c (remap_gimple_stmt): Clear VUSE/VDEF.
	(expand_call_inline): Unlink the calls virtual operands before
	replacing it.
	(tree_function_versioning): Do not call update_ssa if we are not
	updating clones.  Simplify.
	* tree-ssa-phiprop.c (phivn_valid_p): Adjust.
	(propagate_with_phi): Likewise..
	* tree-outof-ssa.c (create_temp): Remove memory tag and call
	clobber code.  Assert we are not aliased or global.
	* tree-flow.h: Include tree-ssa-alias.h
	(enum escape_type): Remove.
	(struct mem_sym_stats_d): Likewise.
	(struct mem_ref_stats_d): Likewise.
	(struct gimple_df): Add vop member.  Remove global_var,
	call_clobbered_vars, call_used_vars, addressable_vars,
	aliases_compted_p and mem_ref_stats members.  Add syms_to_rename,
	escaped and callused members.
	(struct ptr_info_def): Remove all members, add points-to solution
	member pt.
	(struct var_ann_d): Remove in_vuse_list, in_vdef_list,
	call_clobbered, escape_mask, mpt and symbol_mem_tag members.
	* Makefile.in (TREE_FLOW_H): Add tree-ssa-alias.h.
	(tree-ssa-structalias.o): Remove tree-ssa-structalias.h.
	(tree-ssa-alias.o): Likewise.
	(toplev.o): Add tree-ssa-alias.h
	(GTFILES): Remove tree-ssa-structalias.h, add tree-ssa-alias.h.
	* gimple.c (gimple_set_bb): Fix off-by-one error.
	(is_gimple_reg): Do not handle memory tags.
	(gimple_copy): Also copy virtual operands.
	Delay updating the statement.  Do not reset loaded and stored syms.
	(gimple_set_stored_syms): Remove.
	(gimple_set_loaded_syms): Likewise.
	(gimple_call_copy_skip_args): Copy the virtual operands
	and mark the new statement modified.
	* tree-ssa-structalias.c (may_alias_p): Remove.
	(set_uids_in_ptset): Take the alias set to prune with as
	parameter.  Fold in the alias test of may_alias_p.
	(compute_points_to_sets): Compute whether a ptr is dereferenced
	in a local sbitmap.
	(process_constraint): Deal with &ANYTHING on the lhs, reject all
	other ADDRESSOF constraints on the lhs.
	(get_constraint_for_component_ref): Assert that we don't get
	ADDRESSOF constraints from the base of the reference.
	Properly generate UNKNOWN_OFFSET for DEREF if needed.
	(struct variable_info): Remove collapsed_to member.
	(get_varinfo_fc): Remove.
	(new_var_info): Do not set collapsed_to.
	(dump_constraint): Do not follow cycles.
	(dump_constraint_graph): Likewise.
	(build_pred_graph): Likewise.
	(build_succ_graph): Likewise.
	(rewrite_constraints): Likewise.
	(do_simple_structure_copy): Remove.
	(do_rhs_deref_structure_copy): Remove.
	(do_lhs_deref_structure_copy): Remove.
	(collapse_rest_of_var): Remove.
	(do_structure_copy): Re-implement.
	(pta_stats): New global variable.
	(dump_pta_stats): New function.
	(struct constraint_expr): Make offset signed.
	(UNKNOWN_OFFSET): Define special value.
	(dump_constraint): Dump UNKNOWN_OFFSET as UNKNOWN.
	(solution_set_expand): New helper function split out from ...
	(do_sd_constraint): ... here.
	(solution_set_add): Handle UNKNOWN_OFFSET.  Handle negative offsets.
	(do_ds_constraint): Likewise.
	(do_sd_constraint): Likewise.  Do not special-case ESCAPED = *ESCAPED
	and CALLUSED = *CALLUSED.
	(set_union_with_increment): Make inc argument signed.
	(type_safe): Remove.
	(get_constraint_for_ptr_offset): Handle unknown and negative
	constant offsets.
	(first_vi_for_offset): Handle offsets before start.  Bail
	out early for offsets beyond the variable extent.
	(first_or_preceding_vi_for_offset): New function.
	(init_base_vars): Add ESCAPED = ESCAPED + UNKNOWN_OFFSET constraint.
	Together with ESCAPED = *ESCAPED this properly computes reachability.
	(find_what_var_points_to): New function.
	(find_what_p_points_to): Implement in terms of find_what_var_points_to.
	(pt_solution_reset, pt_solution_empty_p, pt_solution_includes_global,
	pt_solution_includes_1, pt_solution_includes, pt_solutions_intersect_1,
	pt_solutions_intersect): New functions.
	(compute_call_used_vars): Remove.
	(compute_may_aliases): New main entry into PTA computation.
	* gimple.h (gimple_p): New typedef.
	(struct gimple_statement_base): Remove references_memory_p.
	(struct gimple_statement_with_memory_ops_base): Remove
	vdef_ops, vuse_ops, stores and loads members.  Add vdef and vuse
	members.
	(gimple_vuse_ops, gimple_set_vuse_ops, gimple_vdef_ops,
	gimple_set_vdef_ops, gimple_loaded_syms, gimple_stored_syms,
	gimple_set_references_memory): Remove.
	(gimple_vuse_op, gimple_vdef_op, gimple_vuse, gimple_vdef,
	gimple_vuse_ptr, gimple_vdef_ptri, gimple_set_vuse, gimple_set_vdef):
	New functions.
	* tree-cfg.c (move_block_to_fn): Fix off-by-one error.
	(verify_expr): Allow RESULT_DECL.
	(gimple_duplicate_bb): Do not copy virtual operands.
	(gimple_duplicate_sese_region): Adjust.
	(gimple_duplicate_sese_tail): Likewise.
	(mark_virtual_ops_in_region): Remove.
	(move_sese_region_to_fn): Do not call it.
	* passes.c (init_optimization_passes): Remove pass_reset_cc_flags
	and pass_simple_dse.
	(execute_function_todo): Handle TODO_update_address_taken,
	call execute_update_addresses_taken for TODO_rebuild_alias.
	(execute_todo): Adjust.
	(execute_one_pass): Init dump files early.
	* ipa-struct-reorg.c (finalize_var_creation): Do not mark vars
	call-clobbered.
	(create_general_new_stmt): Clear vops.
	* tree-ssa-reassoc.c (get_rank): Adjust.
	* tree-vect-slp.c (vect_create_mask_and_perm): Do not mark
	symbols for renaming.
	* params.def (PARAM_MAX_ALIASED_VOPS): Remove.
	(PARAM_AVG_ALIASED_VOPS): Likewise.
	* tree-ssanames.c (init_ssanames): Allocate SYMS_TO_RENAME.
	(duplicate_ssa_name_ptr_info): No need to copy the shared bitmaps.
	* tree-ssa-operands.c: Simplify for new virtual operand
	representation.
	(operand_build_cmp, copy_virtual_operands,
	create_ssa_artificial_load_stmt, add_to_addressable_set,
	gimple_add_to_addresses_taken): Remove public functions.
	(unlink_stmt_vdef): New function.

	* gcc.dg/pr19633-1.c: Adjust.
	* gcc.dg/torture/pta-callused-1.c: Likewise.
	* gcc.dg/torture/pr39074-2.c: Likewise.
	* gcc.dg/torture/pr39074.c: Likewise.
	* gcc.dg/torture/pta-ptrarith-3.c: New testcase.
	* gcc.dg/torture/pr30375.c: Adjust.
	* gcc.dg/torture/pr33563.c: Likewise.
	* gcc.dg/torture/pr33870.c: Likewise.
	* gcc.dg/torture/pr33560.c: Likewise.
	* gcc.dg/torture/pta-structcopy-1.c: New testcase.
	* gcc.dg/torture/ssa-pta-fn-1.c: Likewise.
	* gcc.dg/tree-ssa/alias-15.c: Remove.
	* gcc.dg/tree-ssa/ssa-dce-4.c: New testcase.
	* gcc.dg/tree-ssa/pr26421.c: Adjust.
	* gcc.dg/tree-ssa/ssa-fre-10.c: XFAIL.
	* gcc.dg/tree-ssa/ssa-dce-5.c: New testcase.
	* gcc.dg/tree-ssa/pr23382.c: Adjust.
	* gcc.dg/tree-ssa/ssa-fre-20.c: New testcase.
	* gcc.dg/tree-ssa/alias-16.c: Adjust.
	* gcc.dg/tree-ssa/ssa-fre-13.c: Likewise.
	* gcc.dg/tree-ssa/ssa-fre-14.c: Likewise.
	* gcc.dg/tree-ssa/alias-18.c: Likewise.
	* gcc.dg/tree-ssa/ssa-fre-15.c: Likewise.
	* gcc.dg/tree-ssa/ssa-lim-3.c: Likewise.
	* gcc.dg/tree-ssa/alias-19.c: Likewise.
	* gcc.dg/tree-ssa/pta-ptrarith-1.c: New testcase.
	* gcc.dg/tree-ssa/pr13146.c: Likewise.
	* gcc.dg/tree-ssa/ssa-pre-23.c: Likewise.
	* gcc.dg/tree-ssa/pta-ptrarith-2.c: Likewise.
	* gcc.dg/tree-ssa/ssa-fre-18.c: Likewise.
	* gcc.dg/tree-ssa/ssa-pre-24.c: New XFAILed testcase.
	* gcc.dg/tree-ssa/ssa-fre-19.c: New testcase.
	* gcc.dg/tree-ssa/alias-20.c: Likewise.
	* gcc.dg/tree-ssa/ssa-dse-12.c: Likewise.
	* gcc.dg/tree-ssa/pr38895.c: Likewise.
	* gcc.dg/uninit-B.c: XFAIL.
	* gcc.dg/vect/no-vfa-vect-43.c: Adjust.
	* gcc.dg/uninit-pr19430.c: XFAIL.
	* g++.dg/tree-ssa/pr13146.C: New testcase.
	* g++.dg/opt/pr36187.C: Adjust.
	* g++.dg/torture/20090329-1.C: New testcase.

Added:
    trunk/gcc/testsuite/g++.dg/torture/20090329-1.C
      - copied unchanged from r145492, branches/alias-improvements/gcc/testsuite/g++.dg/torture/20090329-1.C
    trunk/gcc/testsuite/g++.dg/tree-ssa/pr13146.C
      - copied unchanged from r145492, branches/alias-improvements/gcc/testsuite/g++.dg/tree-ssa/pr13146.C
    trunk/gcc/testsuite/gcc.dg/torture/pta-ptrarith-3.c
      - copied unchanged from r145492, branches/alias-improvements/gcc/testsuite/gcc.dg/torture/pta-ptrarith-3.c
    trunk/gcc/testsuite/gcc.dg/torture/pta-structcopy-1.c
      - copied unchanged from r145492, branches/alias-improvements/gcc/testsuite/gcc.dg/torture/pta-structcopy-1.c
    trunk/gcc/testsuite/gcc.dg/torture/ssa-pta-fn-1.c
      - copied unchanged from r145492, branches/alias-improvements/gcc/testsuite/gcc.dg/torture/ssa-pta-fn-1.c
    trunk/gcc/testsuite/gcc.dg/tree-ssa/alias-20.c
      - copied unchanged from r145492, branches/alias-improvements/gcc/testsuite/gcc.dg/tree-ssa/alias-20.c
    trunk/gcc/testsuite/gcc.dg/tree-ssa/pr13146.c
      - copied unchanged from r145492, branches/alias-improvements/gcc/testsuite/gcc.dg/tree-ssa/pr13146.c
    trunk/gcc/testsuite/gcc.dg/tree-ssa/pr38895.c
      - copied unchanged from r145492, branches/alias-improvements/gcc/testsuite/gcc.dg/tree-ssa/pr38895.c
    trunk/gcc/testsuite/gcc.dg/tree-ssa/pta-ptrarith-1.c
      - copied unchanged from r145492, branches/alias-improvements/gcc/testsuite/gcc.dg/tree-ssa/pta-ptrarith-1.c
    trunk/gcc/testsuite/gcc.dg/tree-ssa/pta-ptrarith-2.c
      - copied unchanged from r145492, branches/alias-improvements/gcc/testsuite/gcc.dg/tree-ssa/pta-ptrarith-2.c
    trunk/gcc/testsuite/gcc.dg/tree-ssa/ssa-dce-4.c
      - copied unchanged from r145492, branches/alias-improvements/gcc/testsuite/gcc.dg/tree-ssa/ssa-dce-4.c
    trunk/gcc/testsuite/gcc.dg/tree-ssa/ssa-dce-5.c
      - copied unchanged from r145492, branches/alias-improvements/gcc/testsuite/gcc.dg/tree-ssa/ssa-dce-5.c
    trunk/gcc/testsuite/gcc.dg/tree-ssa/ssa-dse-12.c
      - copied unchanged from r145492, branches/alias-improvements/gcc/testsuite/gcc.dg/tree-ssa/ssa-dse-12.c
    trunk/gcc/testsuite/gcc.dg/tree-ssa/ssa-fre-18.c
      - copied unchanged from r145492, branches/alias-improvements/gcc/testsuite/gcc.dg/tree-ssa/ssa-fre-18.c
    trunk/gcc/testsuite/gcc.dg/tree-ssa/ssa-fre-19.c
      - copied unchanged from r145492, branches/alias-improvements/gcc/testsuite/gcc.dg/tree-ssa/ssa-fre-19.c
    trunk/gcc/testsuite/gcc.dg/tree-ssa/ssa-fre-20.c
      - copied unchanged from r145492, branches/alias-improvements/gcc/testsuite/gcc.dg/tree-ssa/ssa-fre-20.c
    trunk/gcc/testsuite/gcc.dg/tree-ssa/ssa-pre-23.c
      - copied unchanged from r145492, branches/alias-improvements/gcc/testsuite/gcc.dg/tree-ssa/ssa-pre-23.c
    trunk/gcc/testsuite/gcc.dg/tree-ssa/ssa-pre-24.c
      - copied unchanged from r145492, branches/alias-improvements/gcc/testsuite/gcc.dg/tree-ssa/ssa-pre-24.c
    trunk/gcc/tree-ssa-alias.h
      - copied unchanged from r145492, branches/alias-improvements/gcc/tree-ssa-alias.h
Removed:
    trunk/gcc/testsuite/gcc.dg/tree-ssa/alias-15.c
    trunk/gcc/tree-ssa-structalias.h
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/Makefile.in
    trunk/gcc/alias.c
    trunk/gcc/alias.h
    trunk/gcc/doc/invoke.texi
    trunk/gcc/doc/tree-ssa.texi
    trunk/gcc/gimple-pretty-print.c
    trunk/gcc/gimple.c
    trunk/gcc/gimple.h
    trunk/gcc/graphite.c
    trunk/gcc/ipa-cp.c
    trunk/gcc/ipa-pure-const.c
    trunk/gcc/ipa-reference.c
    trunk/gcc/ipa-struct-reorg.c
    trunk/gcc/lambda-code.c
    trunk/gcc/omp-low.c
    trunk/gcc/opts.c
    trunk/gcc/params.def
    trunk/gcc/params.h
    trunk/gcc/passes.c
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/testsuite/g++.dg/opt/pr36187.C
    trunk/gcc/testsuite/gcc.dg/pr19633-1.c
    trunk/gcc/testsuite/gcc.dg/torture/pr30375.c
    trunk/gcc/testsuite/gcc.dg/torture/pr33560.c
    trunk/gcc/testsuite/gcc.dg/torture/pr33563.c
    trunk/gcc/testsuite/gcc.dg/torture/pr33870.c
    trunk/gcc/testsuite/gcc.dg/torture/pr39074-2.c
    trunk/gcc/testsuite/gcc.dg/torture/pr39074.c
    trunk/gcc/testsuite/gcc.dg/torture/pta-callused-1.c
    trunk/gcc/testsuite/gcc.dg/tree-ssa/alias-16.c
    trunk/gcc/testsuite/gcc.dg/tree-ssa/alias-18.c
    trunk/gcc/testsuite/gcc.dg/tree-ssa/alias-19.c
    trunk/gcc/testsuite/gcc.dg/tree-ssa/pr23382.c
    trunk/gcc/testsuite/gcc.dg/tree-ssa/pr26421.c
    trunk/gcc/testsuite/gcc.dg/tree-ssa/ssa-fre-10.c
    trunk/gcc/testsuite/gcc.dg/tree-ssa/ssa-fre-13.c
    trunk/gcc/testsuite/gcc.dg/tree-ssa/ssa-fre-14.c
    trunk/gcc/testsuite/gcc.dg/tree-ssa/ssa-fre-15.c
    trunk/gcc/testsuite/gcc.dg/tree-ssa/ssa-lim-3.c
    trunk/gcc/testsuite/gcc.dg/uninit-B.c
    trunk/gcc/testsuite/gcc.dg/uninit-pr19430.c
    trunk/gcc/testsuite/gcc.dg/vect/no-vfa-vect-43.c
    trunk/gcc/timevar.def
    trunk/gcc/toplev.c
    trunk/gcc/tree-call-cdce.c
    trunk/gcc/tree-cfg.c
    trunk/gcc/tree-complex.c
    trunk/gcc/tree-data-ref.c
    trunk/gcc/tree-data-ref.h
    trunk/gcc/tree-dfa.c
    trunk/gcc/tree-dump.c
    trunk/gcc/tree-eh.c
    trunk/gcc/tree-flow-inline.h
    trunk/gcc/tree-flow.h
    trunk/gcc/tree-inline.c
    trunk/gcc/tree-into-ssa.c
    trunk/gcc/tree-loop-distribution.c
    trunk/gcc/tree-outof-ssa.c
    trunk/gcc/tree-pass.h
    trunk/gcc/tree-predcom.c
    trunk/gcc/tree-pretty-print.c
    trunk/gcc/tree-sra.c
    trunk/gcc/tree-ssa-address.c
    trunk/gcc/tree-ssa-alias.c
    trunk/gcc/tree-ssa-ccp.c
    trunk/gcc/tree-ssa-coalesce.c
    trunk/gcc/tree-ssa-copy.c
    trunk/gcc/tree-ssa-copyrename.c
    trunk/gcc/tree-ssa-dce.c
    trunk/gcc/tree-ssa-dom.c
    trunk/gcc/tree-ssa-dse.c
    trunk/gcc/tree-ssa-forwprop.c
    trunk/gcc/tree-ssa-ifcombine.c
    trunk/gcc/tree-ssa-live.c
    trunk/gcc/tree-ssa-loop-im.c
    trunk/gcc/tree-ssa-loop-ivcanon.c
    trunk/gcc/tree-ssa-loop-ivopts.c
    trunk/gcc/tree-ssa-loop-niter.c
    trunk/gcc/tree-ssa-loop-prefetch.c
    trunk/gcc/tree-ssa-operands.c
    trunk/gcc/tree-ssa-operands.h
    trunk/gcc/tree-ssa-phiprop.c
    trunk/gcc/tree-ssa-pre.c
    trunk/gcc/tree-ssa-propagate.c
    trunk/gcc/tree-ssa-reassoc.c
    trunk/gcc/tree-ssa-sccvn.c
    trunk/gcc/tree-ssa-sccvn.h
    trunk/gcc/tree-ssa-sink.c
    trunk/gcc/tree-ssa-structalias.c
    trunk/gcc/tree-ssa-ter.c
    trunk/gcc/tree-ssa.c
    trunk/gcc/tree-ssanames.c
    trunk/gcc/tree-tailcall.c
    trunk/gcc/tree-vect-data-refs.c
    trunk/gcc/tree-vect-loop-manip.c
    trunk/gcc/tree-vect-slp.c
    trunk/gcc/tree-vect-stmts.c
    trunk/gcc/tree-vectorizer.h
    trunk/gcc/tree-vrp.c
    trunk/gcc/tree.c
    trunk/gcc/tree.def
    trunk/gcc/tree.h
    trunk/gcc/treestruct.def
Comment 15 Richard Biener 2009-04-03 10:27:58 UTC 
Fixed.