On Fri, Jul 31, 2020 at 12:30 PM Martin Liška <mli...@suse.cz> wrote:
>
> Hey.
>
> Motivation of the patch is to allow vectorization of an entire BB.
> So far we bail out a sub-BB region when we reach a stmt for which
> vect_find_stmt_data_reference returns false. That's replaced with
> recoding of groups of the data references.
>
> We can newly vectorize code like:
>
> void foo();
> void bar (int i, double *a, double *b)
> {
> double tem1 = a[2*i];
> double tem2 = 2*a[2*i+1];
> foo ();
> b[2*i] = 2*tem1;
> b[2*i+1] = tem2;
> }
>
> into:
> <bb 2> [local count: 1073741824]:
> _1 = i_12(D) * 2;
> _2 = (long unsigned int) _1;
> _3 = _2 * 8;
> _4 = a_13(D) + _3;
> vect_tem1_15.5_24 = MEM <vector(2) double> [(double *)_4];
> vect__10.6_25 = vect_tem1_15.5_24 * { 2.0e+0, 2.0e+0 };
> foo ();
> _9 = b_18(D) + _3;
> MEM <vector(2) double> [(double *)_9] = vect__10.6_25;
> return;
>
> Patch can bootstrap on x86_64-linux-gnu and survives regression tests.
OK with some minor changes, see below
> Thoughs?
> Martin
>
> gcc/ChangeLog:
>
> * tree-vect-data-refs.c (dr_group_sort_cmp): Work on
> data_ref_pair.
> (vect_analyze_data_ref_accesses): Work on groups.
> (vect_find_stmt_data_reference): Add group_id argument and fill
> up dataref_groups vector.
> * tree-vect-loop.c (vect_get_datarefs_in_loop): Pass new
> arguments.
> (vect_analyze_loop_2): Likewise.
> * tree-vect-slp.c (vect_slp_analyze_bb_1): Pass argument.
> (vect_slp_bb_region): Likewise.
> (vect_slp_region): Likewise.
> (vect_slp_bb):Work on the entire BB.
> * tree-vectorizer.h (vect_analyze_data_ref_accesses): Add new
> argument.
> (vect_find_stmt_data_reference): Likewise.
>
> gcc/testsuite/ChangeLog:
>
> * gcc.dg/vect/bb-slp-38.c: Adjust pattern as now we only process
> a single vectorization and now 2 partial.
> * gcc.dg/vect/bb-slp-45.c: New test.
> ---
> gcc/testsuite/gcc.dg/vect/bb-slp-38.c | 2 +-
> gcc/testsuite/gcc.dg/vect/bb-slp-45.c | 36 ++++++++++++
> gcc/tree-vect-data-refs.c | 63 +++++++++++++-------
> gcc/tree-vect-loop.c | 5 +-
> gcc/tree-vect-slp.c | 82 ++++++++++-----------------
> gcc/tree-vectorizer.h | 5 +-
> 6 files changed, 118 insertions(+), 75 deletions(-)
> create mode 100644 gcc/testsuite/gcc.dg/vect/bb-slp-45.c
>
> diff --git a/gcc/testsuite/gcc.dg/vect/bb-slp-38.c
> b/gcc/testsuite/gcc.dg/vect/bb-slp-38.c
> index 59aec54fffd..9c57ea3c2c1 100644
> --- a/gcc/testsuite/gcc.dg/vect/bb-slp-38.c
> +++ b/gcc/testsuite/gcc.dg/vect/bb-slp-38.c
> @@ -41,4 +41,4 @@ int main()
> }
>
> /* { dg-final { scan-tree-dump "basic block vectorized" "slp2" { target
> vect_perm } } } */
> -/* { dg-final { scan-tree-dump-times "basic block part vectorized" 2 "slp2"
> { target vect_perm } } } */
> +/* { dg-final { scan-tree-dump "basic block part vectorized" "slp2" { target
> vect_perm } } } */
> diff --git a/gcc/testsuite/gcc.dg/vect/bb-slp-45.c
> b/gcc/testsuite/gcc.dg/vect/bb-slp-45.c
> new file mode 100644
> index 00000000000..4107a34cb93
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/vect/bb-slp-45.c
> @@ -0,0 +1,36 @@
> +/* { dg-require-effective-target vect_double } */
> +
> +#include "tree-vect.h"
> +
> +extern void abort (void);
> +
> +double a[8], b[8];
> +int x;
> +
> +void __attribute__((noinline,noclone))
> +bar (void)
> +{
> + x = 1;
> +}
> +
> +void __attribute__((noinline,noclone))
> +foo(int i)
> +{
> + double tem1 = a[2*i];
> + double tem2 = 2*a[2*i+1];
> + bar ();
> + b[2*i] = 2*tem1;
> + b[2*i+1] = tem2;
> +}
> +
> +int main()
> +{
> + int i;
> + check_vect ();
> + for (i = 0; i < 8; ++i)
> + b[i] = i;
> + foo (2);
> + return 0;
> +}
> +
> +/* { dg-final { scan-tree-dump "basic block vectorized" "slp2" } } */
> diff --git a/gcc/tree-vect-data-refs.c b/gcc/tree-vect-data-refs.c
> index a78ae61d1b0..36e10ff3619 100644
> --- a/gcc/tree-vect-data-refs.c
> +++ b/gcc/tree-vect-data-refs.c
> @@ -2757,14 +2757,18 @@ vect_analyze_data_ref_access (vec_info *vinfo,
> dr_vec_info *dr_info)
> return vect_analyze_group_access (vinfo, dr_info);
> }
>
> +typedef std::pair<data_reference_p, int> data_ref_pair;
> +
> /* Compare two data-references DRA and DRB to group them into chunks
> suitable for grouping. */
>
> static int
> dr_group_sort_cmp (const void *dra_, const void *drb_)
> {
> - data_reference_p dra = *(data_reference_p *)const_cast<void *>(dra_);
> - data_reference_p drb = *(data_reference_p *)const_cast<void *>(drb_);
> + data_ref_pair dra_pair = *(data_ref_pair *)const_cast<void *>(dra_);
> + data_ref_pair drb_pair = *(data_ref_pair *)const_cast<void *>(drb_);
> + data_reference_p dra = dra_pair.first;
> + data_reference_p drb = drb_pair.first;
> int cmp;
>
> /* Stabilize sort. */
> @@ -2772,10 +2776,13 @@ dr_group_sort_cmp (const void *dra_, const void *drb_)
> return 0;
>
> /* DRs in different loops never belong to the same group. */
Comment needs to be adjusted to mention basic-block instead of loop
> - loop_p loopa = gimple_bb (DR_STMT (dra))->loop_father;
> - loop_p loopb = gimple_bb (DR_STMT (drb))->loop_father;
> - if (loopa != loopb)
> - return loopa->num < loopb->num ? -1 : 1;
> + int bb_index1 = gimple_bb (DR_STMT (dra))->index;
> + int bb_index2 = gimple_bb (DR_STMT (drb))->index;
> + if (bb_index1 != bb_index2)
> + return bb_index1 < bb_index2 ? -1 : 1;
> +
> + if (dra_pair.second != drb_pair.second)
> + return dra_pair.second < drb_pair.second ? -1 : 1;
Please add a comment that this compares the DR group
(not obvious because it says .second)
>
> /* Ordering of DRs according to base. */
> cmp = data_ref_compare_tree (DR_BASE_ADDRESS (dra),
> @@ -2881,11 +2888,11 @@ can_group_stmts_p (stmt_vec_info stmt1_info,
> stmt_vec_info stmt2_info,
> FORNOW: handle only arrays and pointer accesses. */
>
> opt_result
> -vect_analyze_data_ref_accesses (vec_info *vinfo)
> +vect_analyze_data_ref_accesses (vec_info *vinfo,
> + vec<int> *dataref_groups)
> {
> unsigned int i;
> vec<data_reference_p> datarefs = vinfo->shared->datarefs;
> - struct data_reference *dr;
>
> DUMP_VECT_SCOPE ("vect_analyze_data_ref_accesses");
>
> @@ -2895,14 +2902,21 @@ vect_analyze_data_ref_accesses (vec_info *vinfo)
> /* Sort the array of datarefs to make building the interleaving chains
> linear. Don't modify the original vector's order, it is needed for
> determining what dependencies are reversed. */
> - vec<data_reference_p> datarefs_copy = datarefs.copy ();
> + vec<data_ref_pair> datarefs_copy;
> + datarefs_copy.create (datarefs.length ());
> + for (unsigned i = 0; i < datarefs.length (); i++)
> + {
> + int group_id = dataref_groups ? (*dataref_groups)[i] : 0;
> + datarefs_copy.safe_push (data_ref_pair (datarefs[i], group_id));
quick_push
> + }
> datarefs_copy.qsort (dr_group_sort_cmp);
> hash_set<stmt_vec_info> to_fixup;
>
> /* Build the interleaving chains. */
> for (i = 0; i < datarefs_copy.length () - 1;)
> {
> - data_reference_p dra = datarefs_copy[i];
> + data_reference_p dra = datarefs_copy[i].first;
> + int dra_group_id = datarefs_copy[i].second;
> dr_vec_info *dr_info_a = vinfo->lookup_dr (dra);
> stmt_vec_info stmtinfo_a = dr_info_a->stmt;
> stmt_vec_info lastinfo = NULL;
> @@ -2914,7 +2928,8 @@ vect_analyze_data_ref_accesses (vec_info *vinfo)
> }
> for (i = i + 1; i < datarefs_copy.length (); ++i)
> {
> - data_reference_p drb = datarefs_copy[i];
> + data_reference_p drb = datarefs_copy[i].first;
> + int drb_group_id = datarefs_copy[i].second;
> dr_vec_info *dr_info_b = vinfo->lookup_dr (drb);
> stmt_vec_info stmtinfo_b = dr_info_b->stmt;
> if (!STMT_VINFO_VECTORIZABLE (stmtinfo_b)
> @@ -2927,10 +2942,14 @@ vect_analyze_data_ref_accesses (vec_info *vinfo)
> matters we can push those to a worklist and re-iterate
> over them. The we can just skip ahead to the next DR here. */
>
> - /* DRs in a different loop should not be put into the same
> + /* DRs in a different BBs should not be put into the same
> interleaving group. */
> - if (gimple_bb (DR_STMT (dra))->loop_father
> - != gimple_bb (DR_STMT (drb))->loop_father)
> + int bb_index1 = gimple_bb (DR_STMT (dra))->index;
> + int bb_index2 = gimple_bb (DR_STMT (drb))->index;
> + if (bb_index1 != bb_index2)
> + break;
> +
> + if (dra_group_id != drb_group_id)
> break;
>
> /* Check that the data-refs have same first location (except init)
> @@ -2977,7 +2996,7 @@ vect_analyze_data_ref_accesses (vec_info *vinfo)
> HOST_WIDE_INT init_a = TREE_INT_CST_LOW (DR_INIT (dra));
> HOST_WIDE_INT init_b = TREE_INT_CST_LOW (DR_INIT (drb));
> HOST_WIDE_INT init_prev
> - = TREE_INT_CST_LOW (DR_INIT (datarefs_copy[i-1]));
> + = TREE_INT_CST_LOW (DR_INIT (datarefs_copy[i-1].first));
> gcc_assert (init_a <= init_b
> && init_a <= init_prev
> && init_prev <= init_b);
> @@ -2985,7 +3004,7 @@ vect_analyze_data_ref_accesses (vec_info *vinfo)
> /* Do not place the same access in the interleaving chain twice. */
> if (init_b == init_prev)
> {
> - gcc_assert (gimple_uid (DR_STMT (datarefs_copy[i-1]))
> + gcc_assert (gimple_uid (DR_STMT (datarefs_copy[i-1].first))
> < gimple_uid (DR_STMT (drb)));
> /* Simply link in duplicates and fix up the chain below. */
> }
> @@ -3098,9 +3117,10 @@ vect_analyze_data_ref_accesses (vec_info *vinfo)
> to_fixup.add (newgroup);
> }
>
> - FOR_EACH_VEC_ELT (datarefs_copy, i, dr)
> + data_ref_pair *dr_pair;
> + FOR_EACH_VEC_ELT (datarefs_copy, i, dr_pair)
> {
> - dr_vec_info *dr_info = vinfo->lookup_dr (dr);
> + dr_vec_info *dr_info = vinfo->lookup_dr (dr_pair->first);
> if (STMT_VINFO_VECTORIZABLE (dr_info->stmt)
> && !vect_analyze_data_ref_access (vinfo, dr_info))
> {
> @@ -3991,7 +4011,8 @@ vect_check_gather_scatter (stmt_vec_info stmt_info,
> loop_vec_info loop_vinfo,
>
> opt_result
> vect_find_stmt_data_reference (loop_p loop, gimple *stmt,
> - vec<data_reference_p> *datarefs)
> + vec<data_reference_p> *datarefs,
> + vec<int> *dataref_groups, int group_id)
You are always passing NULL here so simply avoid this and the following changes.
OK with those changes.
Thanks,
Richard.
> {
> /* We can ignore clobbers for dataref analysis - they are removed during
> loop vectorization and BB vectorization checks dependences with a
> @@ -4118,6 +4139,8 @@ vect_find_stmt_data_reference (loop_p loop, gimple
> *stmt,
> newdr->aux = (void *) (-1 - tree_to_uhwi (arg2));
> free_data_ref (dr);
> datarefs->safe_push (newdr);
> + if (dataref_groups)
> + dataref_groups->safe_push (group_id);
> return opt_result::success ();
> }
> }
> @@ -4127,6 +4150,8 @@ vect_find_stmt_data_reference (loop_p loop, gimple
> *stmt,
> }
>
> datarefs->safe_push (dr);
> + if (dataref_groups)
> + dataref_groups->safe_push (group_id);
> return opt_result::success ();
> }
>
> diff --git a/gcc/tree-vect-loop.c b/gcc/tree-vect-loop.c
> index 185019c3305..2326d670bee 100644
> --- a/gcc/tree-vect-loop.c
> +++ b/gcc/tree-vect-loop.c
> @@ -1865,7 +1865,8 @@ vect_get_datarefs_in_loop (loop_p loop, basic_block
> *bbs,
> if (is_gimple_debug (stmt))
> continue;
> ++(*n_stmts);
> - opt_result res = vect_find_stmt_data_reference (loop, stmt, datarefs);
> + opt_result res = vect_find_stmt_data_reference (loop, stmt, datarefs,
> + NULL, 0);
> if (!res)
> {
> if (is_gimple_call (stmt) && loop->safelen)
> @@ -2087,7 +2088,7 @@ vect_analyze_loop_2 (loop_vec_info loop_vinfo, bool
> &fatal, unsigned *n_stmts)
> /* Analyze the access patterns of the data-refs in the loop (consecutive,
> complex, etc.). FORNOW: Only handle consecutive access pattern. */
>
> - ok = vect_analyze_data_ref_accesses (loop_vinfo);
> + ok = vect_analyze_data_ref_accesses (loop_vinfo, NULL);
> if (!ok)
> {
> if (dump_enabled_p ())
> diff --git a/gcc/tree-vect-slp.c b/gcc/tree-vect-slp.c
> index 72192b5a813..167db076454 100644
> --- a/gcc/tree-vect-slp.c
> +++ b/gcc/tree-vect-slp.c
> @@ -3217,7 +3217,8 @@ vect_slp_check_for_constructors (bb_vec_info bb_vinfo)
> region. */
>
> static bool
> -vect_slp_analyze_bb_1 (bb_vec_info bb_vinfo, int n_stmts, bool &fatal)
> +vect_slp_analyze_bb_1 (bb_vec_info bb_vinfo, int n_stmts, bool &fatal,
> + vec<int> *dataref_groups)
> {
> DUMP_VECT_SCOPE ("vect_slp_analyze_bb");
>
> @@ -3239,7 +3240,7 @@ vect_slp_analyze_bb_1 (bb_vec_info bb_vinfo, int
> n_stmts, bool &fatal)
> return false;
> }
>
> - if (!vect_analyze_data_ref_accesses (bb_vinfo))
> + if (!vect_analyze_data_ref_accesses (bb_vinfo, dataref_groups))
> {
> if (dump_enabled_p ())
> dump_printf_loc (MSG_MISSED_OPTIMIZATION, vect_location,
> @@ -3348,10 +3349,11 @@ vect_slp_analyze_bb_1 (bb_vec_info bb_vinfo, int
> n_stmts, bool &fatal)
> given by DATAREFS. */
>
> static bool
> -vect_slp_bb_region (gimple_stmt_iterator region_begin,
> - gimple_stmt_iterator region_end,
> - vec<data_reference_p> datarefs,
> - unsigned int n_stmts)
> +vect_slp_region (gimple_stmt_iterator region_begin,
> + gimple_stmt_iterator region_end,
> + vec<data_reference_p> datarefs,
> + vec<int> *dataref_groups,
> + unsigned int n_stmts)
> {
> bb_vec_info bb_vinfo;
> auto_vector_modes vector_modes;
> @@ -3378,7 +3380,7 @@ vect_slp_bb_region (gimple_stmt_iterator region_begin,
> bb_vinfo->shared->check_datarefs ();
> bb_vinfo->vector_mode = next_vector_mode;
>
> - if (vect_slp_analyze_bb_1 (bb_vinfo, n_stmts, fatal)
> + if (vect_slp_analyze_bb_1 (bb_vinfo, n_stmts, fatal, dataref_groups)
> && dbg_cnt (vect_slp))
> {
> if (dump_enabled_p ())
> @@ -3473,45 +3475,30 @@ vect_slp_bb_region (gimple_stmt_iterator region_begin,
> bool
> vect_slp_bb (basic_block bb)
> {
> - gimple_stmt_iterator gsi;
> - bool any_vectorized = false;
> -
> - gsi = gsi_after_labels (bb);
> - while (!gsi_end_p (gsi))
> + vec<data_reference_p> datarefs = vNULL;
> + vec<int> dataref_groups = vNULL;
> + int insns = 0;
> + int current_group = 0;
> + gimple_stmt_iterator region_begin = gsi_start_nondebug_after_labels_bb
> (bb);
> + gimple_stmt_iterator region_end = gsi_last_bb (bb);
> + if (!gsi_end_p (region_end))
> + gsi_next (®ion_end);
> +
> + for (gimple_stmt_iterator gsi = gsi_after_labels (bb); !gsi_end_p (gsi);
> + gsi_next (&gsi))
> {
> - gimple_stmt_iterator region_begin = gsi;
> - vec<data_reference_p> datarefs = vNULL;
> - int insns = 0;
> -
> - for (; !gsi_end_p (gsi); gsi_next (&gsi))
> - {
> - gimple *stmt = gsi_stmt (gsi);
> - if (is_gimple_debug (stmt))
> - {
> - /* Skip leading debug stmts. */
> - if (gsi_stmt (region_begin) == stmt)
> - gsi_next (®ion_begin);
> - continue;
> - }
> - insns++;
> -
> - if (gimple_location (stmt) != UNKNOWN_LOCATION)
> - vect_location = stmt;
> + gimple *stmt = gsi_stmt (gsi);
> + if (is_gimple_debug (stmt))
> + continue;
>
> - if (!vect_find_stmt_data_reference (NULL, stmt, &datarefs))
> - break;
> - }
> - if (gsi_end_p (region_begin))
> - break;
> + insns++;
>
> - /* Skip leading unhandled stmts. */
> - if (gsi_stmt (region_begin) == gsi_stmt (gsi))
> - {
> - gsi_next (&gsi);
> - continue;
> - }
> + if (gimple_location (stmt) != UNKNOWN_LOCATION)
> + vect_location = stmt;
>
> - gimple_stmt_iterator region_end = gsi;
> + if (!vect_find_stmt_data_reference (NULL, stmt, &datarefs,
> + &dataref_groups, current_group))
> + ++current_group;
>
> if (insns > param_slp_max_insns_in_bb)
> {
> @@ -3520,17 +3507,10 @@ vect_slp_bb (basic_block bb)
> "not vectorized: too many instructions in "
> "basic block.\n");
> }
> - else if (vect_slp_bb_region (region_begin, region_end, datarefs,
> insns))
> - any_vectorized = true;
> -
> - if (gsi_end_p (region_end))
> - break;
> -
> - /* Skip the unhandled stmt. */
> - gsi_next (&gsi);
> }
>
> - return any_vectorized;
> + return vect_slp_region (region_begin, region_end, datarefs,
> + &dataref_groups, insns);
> }
>
>
> diff --git a/gcc/tree-vectorizer.h b/gcc/tree-vectorizer.h
> index 5466c78c20b..21881a9390c 100644
> --- a/gcc/tree-vectorizer.h
> +++ b/gcc/tree-vectorizer.h
> @@ -1917,14 +1917,15 @@ extern bool vect_slp_analyze_instance_dependence
> (vec_info *, slp_instance);
> extern opt_result vect_enhance_data_refs_alignment (loop_vec_info);
> extern opt_result vect_analyze_data_refs_alignment (loop_vec_info);
> extern bool vect_slp_analyze_instance_alignment (vec_info *, slp_instance);
> -extern opt_result vect_analyze_data_ref_accesses (vec_info *);
> +extern opt_result vect_analyze_data_ref_accesses (vec_info *, vec<int> *);
> extern opt_result vect_prune_runtime_alias_test_list (loop_vec_info);
> extern bool vect_gather_scatter_fn_p (vec_info *, bool, bool, tree, tree,
> tree, int, internal_fn *, tree *);
> extern bool vect_check_gather_scatter (stmt_vec_info, loop_vec_info,
> gather_scatter_info *);
> extern opt_result vect_find_stmt_data_reference (loop_p, gimple *,
> - vec<data_reference_p> *);
> + vec<data_reference_p> *,
> + vec<int> *, int);
> extern opt_result vect_analyze_data_refs (vec_info *, poly_uint64 *, bool
> *);
> extern void vect_record_base_alignments (vec_info *);
> extern tree vect_create_data_ref_ptr (vec_info *,
> --
> 2.27.0
>
