Hello,
and ping.
Thanks,
Martin
On Fri, Sep 01 2023, Martin Jambor wrote:
> Hello
>
> and ping.
>
> Thanks,
>
> Martin
>
>
> On Fri, Aug 18 2023, Martin Jambor wrote:
>> Hi,
>>
>> testing on 32bit arm revealed that even the simplest case of PR 110378
>> was still not resolved there because destructors were returning this
>> pointer. Needless to say, the return value of those destructors often
>> is just not used, which IPA-SRA can already detect in time. Since
>> such enhancement seems generally useful, here it is.
>>
>> The patch simply adds two flag to respective summaries to mark down
>> situations when it encounters either a simple direct use of a default
>> definition SSA_NAME of a parameter, which means that the parameter may
>> still be split when return value is removed, and when any derived use
>> of it is returned, allowing for complete removal in that case, instead
>> of discarding it as a candidate for removal or splitting like we do
>> now. The IPA phase then simply checks that we indeed plan to remove
>> the return value before allowing any transformation to be considered
>> in such cases.
>>
>> Bootstrapped, LTO-bootstrapped and tested on x86_64-linux. OK for
>> master?
>>
>> Thanks,
>>
>> Martin
>>
>>
>> gcc/ChangeLog:
>>
>> 2023-08-18 Martin Jambor <mjam...@suse.cz>
>>
>> PR ipa/110378
>> * ipa-param-manipulation.cc
>> (ipa_param_body_adjustments::mark_dead_statements): Verify that any
>> return uses of PARAM will be removed.
>> (ipa_param_body_adjustments::mark_clobbers_dead): Likewise.
>> * ipa-sra.cc (isra_param_desc): New fields
>> remove_only_when_retval_removed and split_only_when_retval_removed.
>> (struct gensum_param_desc): Likewise. Fix comment long line.
>> (ipa_sra_function_summaries::duplicate): Copy the new flags.
>> (dump_gensum_param_descriptor): Dump the new flags.
>> (dump_isra_param_descriptor): Likewise.
>> (isra_track_scalar_value_uses): New parameter desc. Set its flag
>> remove_only_when_retval_removed when encountering a simple return.
>> (isra_track_scalar_param_local_uses): Replace parameter call_uses_p
>> with desc. Pass it to isra_track_scalar_value_uses and set its
>> call_uses.
>> (ptr_parm_has_nonarg_uses): Accept parameter descriptor as a
>> parameter. If there is a direct return use, mark any..
>> (create_parameter_descriptors): Pass the whole parameter descriptor to
>> isra_track_scalar_param_local_uses and ptr_parm_has_nonarg_uses.
>> (process_scan_results): Copy the new flags.
>> (isra_write_node_summary): Stream the new flags.
>> (isra_read_node_info): Likewise.
>> (adjust_parameter_descriptions): Check that transformations
>> requring return removal only happen when return value is removed.
>> Restructure main loop. Adjust dump message.
>>
>> gcc/testsuite/ChangeLog:
>>
>> 2023-08-18 Martin Jambor <mjam...@suse.cz>
>>
>> PR ipa/110378
>> * gcc.dg/ipa/ipa-sra-32.c: New test.
>> * gcc.dg/ipa/pr110378-4.c: Likewise.
>> * gcc.dg/ipa/ipa-sra-4.c: Use a return value.
>> ---
>> gcc/ipa-param-manipulation.cc | 7 +-
>> gcc/ipa-sra.cc | 247 +++++++++++++++++---------
>> gcc/testsuite/gcc.dg/ipa/ipa-sra-32.c | 30 ++++
>> gcc/testsuite/gcc.dg/ipa/ipa-sra-4.c | 4 +-
>> gcc/testsuite/gcc.dg/ipa/pr110378-4.c | 50 ++++++
>> 5 files changed, 251 insertions(+), 87 deletions(-)
>> create mode 100644 gcc/testsuite/gcc.dg/ipa/ipa-sra-32.c
>> create mode 100644 gcc/testsuite/gcc.dg/ipa/pr110378-4.c
>>
>> diff --git a/gcc/ipa-param-manipulation.cc b/gcc/ipa-param-manipulation.cc
>> index 4a185ddbdf4..ae52f17b2c9 100644
>> --- a/gcc/ipa-param-manipulation.cc
>> +++ b/gcc/ipa-param-manipulation.cc
>> @@ -1163,6 +1163,8 @@ ipa_param_body_adjustments::mark_dead_statements (tree
>> dead_param,
>> stack.safe_push (lhs);
>> }
>> }
>> + else if (gimple_code (stmt) == GIMPLE_RETURN)
>> + gcc_assert (m_adjustments && m_adjustments->m_skip_return);
>> else
>> /* IPA-SRA does not analyze other types of statements. */
>> gcc_unreachable ();
>> @@ -1182,7 +1184,8 @@ ipa_param_body_adjustments::mark_dead_statements (tree
>> dead_param,
>> }
>>
>> /* Put all clobbers of of dereference of default definition of PARAM into
>> - m_dead_stmts. */
>> + m_dead_stmts. If there are returns among uses of the default definition
>> of
>> + PARAM, verify they will be stripped off the return value. */
>>
>> void
>> ipa_param_body_adjustments::mark_clobbers_dead (tree param)
>> @@ -1200,6 +1203,8 @@ ipa_param_body_adjustments::mark_clobbers_dead (tree
>> param)
>> gimple *stmt = USE_STMT (use_p);
>> if (gimple_clobber_p (stmt))
>> m_dead_stmts.add (stmt);
>> + else if (gimple_code (stmt) == GIMPLE_RETURN)
>> + gcc_assert (m_adjustments && m_adjustments->m_skip_return);
>> }
>> }
>>
>> diff --git a/gcc/ipa-sra.cc b/gcc/ipa-sra.cc
>> index edba364f56e..817f29ea62f 100644
>> --- a/gcc/ipa-sra.cc
>> +++ b/gcc/ipa-sra.cc
>> @@ -185,6 +185,13 @@ struct GTY(()) isra_param_desc
>> unsigned split_candidate : 1;
>> /* Is this a parameter passing stuff by reference? */
>> unsigned by_ref : 1;
>> + /* If set, this parameter can only be a candidate for removal if the
>> function
>> + is going to loose its return value. */
>> + unsigned remove_only_when_retval_removed : 1;
>> + /* If set, this parameter can only be a candidate for splitting if the
>> + function is going to loose its return value. Can only be meaningfully
>> set
>> + for by_ref parameters. */
>> + unsigned split_only_when_retval_removed : 1;
>> /* Parameter hint set during IPA analysis when there is a caller which
>> does
>> not construct the argument just to pass it to calls. Only meaningful
>> for
>> by_ref parameters. */
>> @@ -206,7 +213,8 @@ struct gensum_param_desc
>> /* Number of accesses in the access tree rooted in field accesses. */
>> unsigned access_count;
>>
>> - /* If the below is non-zero, this is the number of uses as actual
>> arguments. */
>> + /* If the below is non-zero, this is the number of uses as actual
>> + arguments. */
>> int call_uses;
>> /* Number of times this parameter has been directly passed to. */
>> unsigned ptr_pt_count;
>> @@ -230,6 +238,13 @@ struct gensum_param_desc
>> without performing further checks (for example because it is a
>> REFERENCE_TYPE)? */
>> bool safe_ref;
>> + /* If set, this parameter can only be a candidate for removal if the
>> function
>> + is going to loose its return value. */
>> + bool remove_only_when_retval_removed;
>> + /* If set, this parameter can only be a candidate for splitting if the
>> + function is going to loose its return value. Can only be meaningfully
>> set
>> + for by_ref parameters. */
>> + bool split_only_when_retval_removed;
>> /* Only meaningful for by_ref parameters. If set, this parameter can
>> only be
>> a split candidate if all callers pass pointers that are known to point
>> to
>> a chunk of memory large enough to contain all accesses. */
>> @@ -445,6 +460,8 @@ ipa_sra_function_summaries::duplicate (cgraph_node *,
>> cgraph_node *,
>> d->locally_unused = s->locally_unused;
>> d->split_candidate = s->split_candidate;
>> d->by_ref = s->by_ref;
>> + d->remove_only_when_retval_removed =
>> s->remove_only_when_retval_removed;
>> + d->split_only_when_retval_removed = s->split_only_when_retval_removed;
>> d->not_specially_constructed = s->not_specially_constructed;
>> d->conditionally_dereferenceable = s->conditionally_dereferenceable;
>> d->safe_size_set = s->safe_size_set;
>> @@ -732,17 +749,21 @@ static void
>> dump_gensum_param_descriptor (FILE *f, gensum_param_desc *desc)
>> {
>> if (desc->locally_unused)
>> - fprintf (f, " unused with %i call_uses\n", desc->call_uses);
>> + fprintf (f, " unused with %i call_uses%s\n", desc->call_uses,
>> + desc->remove_only_when_retval_removed ?
>> + " remove_only_when_retval_removed" : "");
>> if (!desc->split_candidate)
>> {
>> fprintf (f, " not a candidate\n");
>> return;
>> }
>> if (desc->by_ref)
>> - fprintf (f, " %s%s by_ref with %u pass throughs\n",
>> + fprintf (f, " %s%s%s by_ref with %u pass throughs\n",
>> desc->safe_ref ? "safe" : "unsafe",
>> desc->conditionally_dereferenceable
>> - ? " conditionally_dereferenceable" : " ok",
>> + ? " conditionally_dereferenceable" : "",
>> + desc->split_only_when_retval_removed
>> + ? " split_only_when_retval_removed" : "",
>> desc->ptr_pt_count);
>>
>> for (gensum_param_access *acc = desc->accesses; acc; acc =
>> acc->next_sibling)
>> @@ -790,6 +811,10 @@ dump_isra_param_descriptor (FILE *f, isra_param_desc
>> *desc, bool hints)
>> fprintf (f, " param_size_limit: %u, size_reached: %u%s",
>> desc->param_size_limit, desc->size_reached,
>> desc->by_ref ? ", by_ref" : "");
>> + if (desc->remove_only_when_retval_removed)
>> + fprintf (f, ", remove_only_when_retval_removed");
>> + if (desc->split_only_when_retval_removed)
>> + fprintf (f, ", split_only_when_retval_removed");
>> if (desc->by_ref && desc->conditionally_dereferenceable)
>> fprintf (f, ", conditionally_dereferenceable");
>> if (hints)
>> @@ -881,16 +906,18 @@ get_single_param_flow_source (const isra_param_flow
>> *param_flow)
>>
>> /* Inspect all uses of NAME and simple arithmetic calculations involving
>> NAME
>> in FUN represented with NODE and return a negative number if any of them
>> is
>> - used for something else than either an actual call argument, simple
>> - arithmetic operation or debug statement. If there are no such uses,
>> return
>> - the number of actual arguments that this parameter eventually feeds to
>> (or
>> - zero if there is none). For any such parameter, mark PARM_NUM as one of
>> its
>> - sources. ANALYZED is a bitmap that tracks which SSA names we have
>> already
>> - started investigating. */
>> + used for something else than either an actual call argument, simple
>> return,
>> + simple arithmetic operation or debug statement. If there are no such
>> uses,
>> + return the number of actual arguments that this parameter eventually
>> feeds
>> + to (or zero if there is none). If there are any simple return uses, set
>> + DESC->remove_only_when_retval_removed. For any such parameter, mark
>> + PARM_NUM as one of its sources. ANALYZED is a bitmap that tracks which
>> SSA
>> + names we have already started investigating. */
>>
>> static int
>> isra_track_scalar_value_uses (function *fun, cgraph_node *node, tree name,
>> - int parm_num, bitmap analyzed)
>> + int parm_num, bitmap analyzed,
>> + gensum_param_desc *desc)
>> {
>> int res = 0;
>> imm_use_iterator imm_iter;
>> @@ -964,7 +991,7 @@ isra_track_scalar_value_uses (function *fun, cgraph_node
>> *node, tree name,
>> if (bitmap_set_bit (analyzed, SSA_NAME_VERSION (lhs)))
>> {
>> int tmp = isra_track_scalar_value_uses (fun, node, lhs, parm_num,
>> - analyzed);
>> + analyzed, desc);
>> if (tmp < 0)
>> {
>> res = tmp;
>> @@ -973,6 +1000,16 @@ isra_track_scalar_value_uses (function *fun,
>> cgraph_node *node, tree name,
>> res += tmp;
>> }
>> }
>> + else if (greturn *gr = dyn_cast<greturn *>(stmt))
>> + {
>> + tree rv = gimple_return_retval (gr);
>> + if (rv != name)
>> + {
>> + res = -1;
>> + break;
>> + }
>> + desc->remove_only_when_retval_removed = true;
>> + }
>> else
>> {
>> res = -1;
>> @@ -985,11 +1022,12 @@ isra_track_scalar_value_uses (function *fun,
>> cgraph_node *node, tree name,
>> /* Inspect all uses of PARM, which must be a gimple register, in FUN (which
>> is
>> also described by NODE) and simple arithmetic calculations involving PARM
>> and return false if any of them is used for something else than either an
>> - actual call argument, simple arithmetic operation or debug statement. If
>> - there are no such uses, return true and store the number of actual
>> arguments
>> - that this parameter eventually feeds to (or zero if there is none) to
>> - *CALL_USES_P. For any such parameter, mark PARM_NUM as one of its
>> - sources.
>> + actual call argument, simple return, simple arithmetic operation or debug
>> + statement. If there are no such uses, return true and store the number
>> of
>> + actual arguments that this parameter eventually feeds to (or zero if
>> there
>> + is none) to DESC->call_uses and set
>> DESC->remove_only_when_retval_removed if
>> + there are any uses in return statemens. For any such parameter, mark
>> + PARM_NUM as one of its sources.
>>
>> This function is similar to ptr_parm_has_nonarg_uses but its results are
>> meant for unused parameter removal, as opposed to splitting of parameters
>> @@ -997,14 +1035,14 @@ isra_track_scalar_value_uses (function *fun,
>> cgraph_node *node, tree name,
>>
>> static bool
>> isra_track_scalar_param_local_uses (function *fun, cgraph_node *node, tree
>> parm,
>> - int parm_num, int *call_uses_p)
>> + int parm_num, gensum_param_desc *desc)
>> {
>> gcc_checking_assert (is_gimple_reg (parm));
>>
>> tree name = ssa_default_def (fun, parm);
>> if (!name || has_zero_uses (name))
>> {
>> - *call_uses_p = 0;
>> + desc->call_uses = 0;
>> return false;
>> }
>>
>> @@ -1014,11 +1052,11 @@ isra_track_scalar_param_local_uses (function *fun,
>> cgraph_node *node, tree parm,
>>
>> bitmap analyzed = BITMAP_ALLOC (NULL);
>> int call_uses = isra_track_scalar_value_uses (fun, node, name, parm_num,
>> - analyzed);
>> + analyzed, desc);
>> BITMAP_FREE (analyzed);
>> if (call_uses < 0)
>> return true;
>> - *call_uses_p = call_uses;
>> + desc->call_uses = call_uses;
>> return false;
>> }
>>
>> @@ -1026,9 +1064,11 @@ isra_track_scalar_param_local_uses (function *fun,
>> cgraph_node *node, tree parm,
>> examine whether there are any nonarg uses that are not actual arguments
>> or
>> otherwise infeasible uses. If so, return true, otherwise return false.
>> Create pass-through IPA flow records for any direct uses as argument
>> calls
>> - and if returning false, store their number into *PT_COUNT_P. NODE and
>> FUN
>> - must represent the function that is currently analyzed, PARM_NUM must be
>> the
>> - index of the analyzed parameter.
>> + and if returning false, store their number into DESC->ptr_pt_count. If
>> + removal of return value would still allow splitting, return true but set
>> + DESC->split_only_when_retval_removed. NODE and FUN must represent the
>> + function that is currently analyzed, PARM_NUM must be the index of the
>> + analyzed parameter.
>>
>> This function is similar to isra_track_scalar_param_local_uses but its
>> results are meant for splitting of parameters passed by reference or
>> turning
>> @@ -1037,7 +1077,7 @@ isra_track_scalar_param_local_uses (function *fun,
>> cgraph_node *node, tree parm,
>>
>> static bool
>> ptr_parm_has_nonarg_uses (cgraph_node *node, function *fun, tree parm,
>> - int parm_num, unsigned *pt_count_p)
>> + int parm_num, gensum_param_desc *desc)
>> {
>> imm_use_iterator ui;
>> gimple *stmt;
>> @@ -1121,6 +1161,19 @@ ptr_parm_has_nonarg_uses (cgraph_node *node, function
>> *fun, tree parm,
>> }
>> }
>> }
>> + else if (greturn *gr = dyn_cast<greturn *>(stmt))
>> + {
>> + tree rv = gimple_return_retval (gr);
>> + if (rv == name)
>> + {
>> + uses_ok++;
>> + /* Analysis for feasibility of removal must have already reached
>> + the conclusion that the flag must be set if it completed. */
>> + gcc_assert (!desc->locally_unused
>> + || desc->remove_only_when_retval_removed);
>> + desc->split_only_when_retval_removed = true;
>> + }
>> + }
>>
>> /* If the number of valid uses does not match the number of
>> uses in this stmt there is an unhandled use. */
>> @@ -1136,7 +1189,7 @@ ptr_parm_has_nonarg_uses (cgraph_node *node, function
>> *fun, tree parm,
>> }
>> }
>>
>> - *pt_count_p = pt_count;
>> + desc->ptr_pt_count = pt_count;
>> return ret;
>> }
>>
>> @@ -1166,7 +1219,6 @@ create_parameter_descriptors (cgraph_node *node,
>> if (dump_file && (dump_flags & TDF_DETAILS))
>> print_generic_expr (dump_file, parm, TDF_UID);
>>
>> - int scalar_call_uses;
>> tree type = TREE_TYPE (parm);
>> if (TREE_THIS_VOLATILE (parm))
>> {
>> @@ -1194,15 +1246,15 @@ create_parameter_descriptors (cgraph_node *node,
>> }
>>
>> if (is_gimple_reg (parm)
>> - && !isra_track_scalar_param_local_uses (fun, node, parm, num,
>> - &scalar_call_uses))
>> + && !isra_track_scalar_param_local_uses (fun, node, parm, num, desc))
>> {
>> - if (dump_file && (dump_flags & TDF_DETAILS))
>> - fprintf (dump_file, " is a scalar with only %i call uses\n",
>> - scalar_call_uses);
>> -
>> desc->locally_unused = true;
>> - desc->call_uses = scalar_call_uses;
>> +
>> + if (dump_file && (dump_flags & TDF_DETAILS))
>> + fprintf (dump_file, " is a scalar with only %i call uses%s\n",
>> + desc->call_uses,
>> + desc->remove_only_when_retval_removed
>> + ? " and return uses": "");
>> }
>>
>> if (POINTER_TYPE_P (type))
>> @@ -1253,8 +1305,7 @@ create_parameter_descriptors (cgraph_node *node,
>> "a va list\n");
>> continue;
>> }
>> - if (ptr_parm_has_nonarg_uses (node, fun, parm, num,
>> - &desc->ptr_pt_count))
>> + if (ptr_parm_has_nonarg_uses (node, fun, parm, num, desc))
>> {
>> if (dump_file && (dump_flags & TDF_DETAILS))
>> fprintf (dump_file, " not a candidate, reference has "
>> @@ -2628,6 +2679,8 @@ process_scan_results (cgraph_node *node, struct
>> function *fun,
>> d->locally_unused = s->locally_unused;
>> d->split_candidate = s->split_candidate;
>> d->by_ref = s->by_ref;
>> + d->remove_only_when_retval_removed =
>> s->remove_only_when_retval_removed;
>> + d->split_only_when_retval_removed = s->split_only_when_retval_removed;
>> d->conditionally_dereferenceable = s->conditionally_dereferenceable;
>>
>> for (gensum_param_access *acc = s->accesses;
>> @@ -2789,6 +2842,8 @@ isra_write_node_summary (output_block *ob, cgraph_node
>> *node)
>> bp_pack_value (&bp, desc->split_candidate, 1);
>> bp_pack_value (&bp, desc->by_ref, 1);
>> gcc_assert (!desc->not_specially_constructed);
>> + bp_pack_value (&bp, desc->remove_only_when_retval_removed, 1);
>> + bp_pack_value (&bp, desc->split_only_when_retval_removed, 1);
>> bp_pack_value (&bp, desc->conditionally_dereferenceable, 1);
>> gcc_assert (!desc->safe_size_set);
>> streamer_write_bitpack (&bp);
>> @@ -2913,6 +2968,8 @@ isra_read_node_info (struct lto_input_block *ib,
>> cgraph_node *node,
>> desc->split_candidate = bp_unpack_value (&bp, 1);
>> desc->by_ref = bp_unpack_value (&bp, 1);
>> desc->not_specially_constructed = 0;
>> + desc->remove_only_when_retval_removed = bp_unpack_value (&bp, 1);
>> + desc->split_only_when_retval_removed = bp_unpack_value (&bp, 1);
>> desc->conditionally_dereferenceable = bp_unpack_value (&bp, 1);
>> desc->safe_size_set = 0;
>> }
>> @@ -4256,8 +4313,32 @@ adjust_parameter_descriptions (cgraph_node *node,
>> isra_func_summary *ifs)
>> {
>> desc->locally_unused = false;
>> desc->split_candidate = false;
>> + continue;
>> + }
>> +
>> + if (desc->split_only_when_retval_removed
>> + && !ifs->m_return_ignored)
>> + {
>> + if (dump_file && (dump_flags & TDF_DETAILS)
>> + && (desc->locally_unused || desc->split_candidate))
>> + dump_bad_cond_indices.safe_push (i);
>> +
>> + gcc_checking_assert (!desc->locally_unused
>> + || desc->remove_only_when_retval_removed);
>> + desc->locally_unused = false;
>> + desc->split_candidate = false;
>> + continue;
>> + }
>> + if (desc->remove_only_when_retval_removed
>> + && !ifs->m_return_ignored)
>> + {
>> + if (dump_file && (dump_flags & TDF_DETAILS)
>> + && (desc->locally_unused || desc->split_candidate))
>> + dump_bad_cond_indices.safe_push (i);
>> +
>> + desc->locally_unused = false;
>> }
>> - else if (check_surviving
>> + if (check_surviving
>> && (i >= surviving_params.length ()
>> || !surviving_params[i]))
>> {
>> @@ -4269,67 +4350,65 @@ adjust_parameter_descriptions (cgraph_node *node,
>> isra_func_summary *ifs)
>> if (dump_file && (dump_flags & TDF_DETAILS))
>> dump_dead_indices.safe_push (i);
>> }
>> - else
>> +
>> + if (desc->split_candidate && desc->conditionally_dereferenceable)
>> {
>> - if (desc->split_candidate && desc->conditionally_dereferenceable)
>> - {
>> - gcc_assert (desc->safe_size_set);
>> - for (param_access *pa : *desc->accesses)
>> - if ((pa->unit_offset + pa->unit_size) > desc->safe_size)
>> - {
>> - if (dump_file && (dump_flags & TDF_DETAILS))
>> - dump_bad_cond_indices.safe_push (i);
>> - desc->split_candidate = false;
>> - break;
>> - }
>> - }
>> + gcc_assert (desc->safe_size_set);
>> + for (param_access *pa : *desc->accesses)
>> + if ((pa->unit_offset + pa->unit_size) > desc->safe_size)
>> + {
>> + if (dump_file && (dump_flags & TDF_DETAILS))
>> + dump_bad_cond_indices.safe_push (i);
>> + desc->split_candidate = false;
>> + break;
>> + }
>> + }
>>
>> - if (desc->split_candidate)
>> + if (desc->split_candidate)
>> + {
>> + if (desc->by_ref && !desc->not_specially_constructed)
>> {
>> - if (desc->by_ref && !desc->not_specially_constructed)
>> - {
>> - int extra_factor
>> - = opt_for_fn (node->decl,
>> - param_ipa_sra_ptrwrap_growth_factor);
>> - desc->param_size_limit = extra_factor *
>> desc->param_size_limit;
>> - }
>> - if (size_would_violate_limit_p (desc, desc->size_reached))
>> - desc->split_candidate = false;
>> + int extra_factor
>> + = opt_for_fn (node->decl,
>> + param_ipa_sra_ptrwrap_growth_factor);
>> + desc->param_size_limit = extra_factor * desc->param_size_limit;
>> }
>> + if (size_would_violate_limit_p (desc, desc->size_reached))
>> + desc->split_candidate = false;
>> + }
>>
>> - /* Avoid ICEs on size-mismatched VIEW_CONVERT_EXPRs when callers and
>> - callees don't agree on types in aggregates and we try to do both
>> - IPA-CP and IPA-SRA. */
>> - if (ipcp_ts && desc->split_candidate)
>> + /* Avoid ICEs on size-mismatched VIEW_CONVERT_EXPRs when callers and
>> + callees don't agree on types in aggregates and we try to do both
>> + IPA-CP and IPA-SRA. */
>> + if (ipcp_ts && desc->split_candidate)
>> + {
>> + ipa_argagg_value_list avl (ipcp_ts);
>> + for (const param_access *pa : desc->accesses)
>> {
>> - ipa_argagg_value_list avl (ipcp_ts);
>> - for (const param_access *pa : desc->accesses)
>> + if (!pa->certain)
>> + continue;
>> + tree value = avl.get_value (i, pa->unit_offset);
>> + if (value
>> + && ((tree_to_uhwi (TYPE_SIZE (TREE_TYPE (value)))
>> + / BITS_PER_UNIT)
>> + != pa->unit_size))
>> {
>> - if (!pa->certain)
>> - continue;
>> - tree value = avl.get_value (i, pa->unit_offset);
>> - if (value
>> - && ((tree_to_uhwi (TYPE_SIZE (TREE_TYPE (value)))
>> - / BITS_PER_UNIT)
>> - != pa->unit_size))
>> - {
>> - desc->split_candidate = false;
>> - if (dump_file && (dump_flags & TDF_DETAILS))
>> - dump_dead_indices.safe_push (i);
>> - break;
>> - }
>> + desc->split_candidate = false;
>> + if (dump_file && (dump_flags & TDF_DETAILS))
>> + dump_dead_indices.safe_push (i);
>> + break;
>> }
>> }
>> -
>> - if (desc->locally_unused || desc->split_candidate)
>> - ret = false;
>> }
>> +
>> + if (desc->locally_unused || desc->split_candidate)
>> + ret = false;
>> }
>>
>> dump_list_of_param_indices (node, "are dead on arrival or have a type "
>> "mismatch with IPA-CP", dump_dead_indices);
>> - dump_list_of_param_indices (node, "are not safe to dereference in all "
>> - "callers", dump_bad_cond_indices);
>> + dump_list_of_param_indices (node, "fail additional requirements ",
>> + dump_bad_cond_indices);
>>
>> return ret;
>> }
>> diff --git a/gcc/testsuite/gcc.dg/ipa/ipa-sra-32.c
>> b/gcc/testsuite/gcc.dg/ipa/ipa-sra-32.c
>> new file mode 100644
>> index 00000000000..f84442816b6
>> --- /dev/null
>> +++ b/gcc/testsuite/gcc.dg/ipa/ipa-sra-32.c
>> @@ -0,0 +1,30 @@
>> +/* { dg-do compile } */
>> +/* { dg-options "-O2 -fdump-ipa-sra" } */
>> +
>> +/* Test that parameters can be removed even when they are returned but the
>> + return is unused. */
>> +
>> +extern int use(int use);
>> +
>> +
>> +static int __attribute__((noinline))
>> +foo(int a, int b, int c)
>> +{
>> + use (c);
>> + return a + b + c;
>> +}
>> +
>> +static int __attribute__((noinline))
>> +bar (int a, int b, int c, int d)
>> +{
>> + return foo (a, b, c + d);
>> +}
>> +
>> +int
>> +baz (int a, int b, int c, int d)
>> +{
>> + bar (a, b, c, d);
>> + return a + d;
>> +}
>> +
>> +/* { dg-final { scan-ipa-dump-times "Will remove parameter" 4 "sra" } } */
>> diff --git a/gcc/testsuite/gcc.dg/ipa/ipa-sra-4.c
>> b/gcc/testsuite/gcc.dg/ipa/ipa-sra-4.c
>> index c86ae8320a7..5b42fbd8329 100644
>> --- a/gcc/testsuite/gcc.dg/ipa/ipa-sra-4.c
>> +++ b/gcc/testsuite/gcc.dg/ipa/ipa-sra-4.c
>> @@ -54,10 +54,10 @@ void caller (void)
>> int b = 10;
>> int c;
>>
>> - ox (&a);
>> + c = ox (&a);
>> ox_ctrl_1 (&a);
>> ox_ctrl_2 (&a);
>> - *holder = ox_improved (1, &b);
>> + *holder = ox_improved (1, &b) + c;
>> return;
>> }
>>
>> diff --git a/gcc/testsuite/gcc.dg/ipa/pr110378-4.c
>> b/gcc/testsuite/gcc.dg/ipa/pr110378-4.c
>> new file mode 100644
>> index 00000000000..32432a8dbe7
>> --- /dev/null
>> +++ b/gcc/testsuite/gcc.dg/ipa/pr110378-4.c
>> @@ -0,0 +1,50 @@
>> +/* { dg-do compile } */
>> +/* { dg-options "-O2 -fdump-ipa-sra -fdump-tree-optimized-slim" } */
>> +
>> +/* This emulates what C++ trstcase pr110378-1.C looks like on 32-bit arm (or
>> + any architecture where the destructor returns this pointer. It verifies
>> + that when it later becomes known that the return value will be removed,
>> we
>> + can split a parameter even in this case. */
>> +
>> +struct S
>> +{
>> + short move_offset_of_a;
>> + int *a;
>> +};
>> +
>> +extern int *allocate_stuff (unsigned);
>> +extern void deallocate_stuff (void *);
>> +
>> +static void
>> +something_like_a_constructor (struct S *p, int len)
>> +{
>> + p->a = allocate_stuff (len * sizeof (int));
>> + *p->a = 4;
>> +}
>> +
>> +static int
>> +operation (struct S *p)
>> +{
>> + return *p->a + 1;
>> +}
>> +
>> +static struct S * __attribute__((noinline))
>> +something_like_an_arm32_destructor (struct S *p)
>> +{
>> + deallocate_stuff (p->a);
>> + return p;
>> +}
>> +
>> +volatile int v2 = 20;
>> +
>> +int test (void)
>> +{
>> + struct S shouldnotexist;
>> + something_like_a_constructor (&shouldnotexist, v2);
>> + v2 = operation (&shouldnotexist);
>> + something_like_an_arm32_destructor (&shouldnotexist);
>> + return 0;
>> +}
>> +
>> +/* { dg-final { scan-ipa-dump "Will split parameter 0" "sra" } } */
>> +/* { dg-final { scan-tree-dump-not "shouldnotexist" "optimized" } } */
>> --
>> 2.41.0
