Hi!
Unlike LOOP_VECTORIZED ifns, LOOP_DIST_ALIAS is added by the ldist pass
and needs to be maintained until the vectorizer, and parloops in between
that. Earlier I've added code to update or drop orig_loop_num during
move_sese_region_to_fn, but that is not sufficient. If we move
the whole pair of loops with the associated LOOP_DIST_ALIAS call into
the outlined loopfn, we need to update the first argument, as orig_loop_num
is likely changing. If the whole triplet (two loops with orig_loop_num
and LOOP_DIST_ALIAS with the same first argument) stays in parent function,
we don't need to adjust it. In all other cases, this patch folds the
LOOP_DIST_ALIAS ifn to the second argument, like the vectorizer does if
it fails to vectorize it.
Bootstrapped/regtested on x86_64-linux, i686-linux, powerpc64le-linux,
bootstrapped on powerpc64-linux, regtest there pending. Ok for trunk?
2017-12-11 Jakub Jelinek <ja...@redhat.com>
PR tree-optimization/83359
* tree-cfg.h (fold_loop_internal_call): Declare.
* tree-vectorizer.c (fold_loop_internal_call): Moved to ...
* tree-cfg.c (fold_loop_internal_call): ... here. No longer static.
(find_loop_dist_alias): New function.
(move_sese_region_to_fn): If any dloop->orig_loop_num value is
updated, also adjust any corresponding LOOP_DIST_ALIAS internal
calls.
* gcc.dg/graphite/pr83359.c: New test.
--- gcc/tree-cfg.h.jj 2017-09-05 23:28:14.000000000 +0200
+++ gcc/tree-cfg.h 2017-12-11 12:35:24.284777550 +0100
@@ -77,6 +77,7 @@ extern void gather_blocks_in_sese_region
vec<basic_block> *bbs_p);
extern void verify_sese (basic_block, basic_block, vec<basic_block> *);
extern bool gather_ssa_name_hash_map_from (tree const &, tree const &, void *);
+extern void fold_loop_internal_call (gimple *, tree);
extern basic_block move_sese_region_to_fn (struct function *, basic_block,
basic_block, tree);
extern void dump_function_to_file (tree, FILE *, dump_flags_t);
--- gcc/tree-vectorizer.c.jj 2017-09-01 09:26:37.000000000 +0200
+++ gcc/tree-vectorizer.c 2017-12-11 12:33:41.436055580 +0100
@@ -464,27 +464,6 @@ vect_loop_vectorized_call (struct loop *
return NULL;
}
-/* Fold loop internal call G like IFN_LOOP_VECTORIZED/IFN_LOOP_DIST_ALIAS
- to VALUE and update any immediate uses of it's LHS. */
-
-static void
-fold_loop_internal_call (gimple *g, tree value)
-{
- tree lhs = gimple_call_lhs (g);
- use_operand_p use_p;
- imm_use_iterator iter;
- gimple *use_stmt;
- gimple_stmt_iterator gsi = gsi_for_stmt (g);
-
- update_call_from_tree (&gsi, value);
- FOR_EACH_IMM_USE_STMT (use_stmt, iter, lhs)
- {
- FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
- SET_USE (use_p, value);
- update_stmt (use_stmt);
- }
-}
-
/* If LOOP has been versioned during loop distribution, return the gurading
internal call. */
--- gcc/tree-cfg.c.jj 2017-12-07 18:05:30.000000000 +0100
+++ gcc/tree-cfg.c 2017-12-11 12:34:55.054140750 +0100
@@ -7337,6 +7337,47 @@ gather_ssa_name_hash_map_from (tree cons
return true;
}
+/* Return LOOP_DIST_ALIAS call if present in BB. */
+
+static gimple *
+find_loop_dist_alias (basic_block bb)
+{
+ gimple *g = last_stmt (bb);
+ if (g == NULL || gimple_code (g) != GIMPLE_COND)
+ return NULL;
+
+ gimple_stmt_iterator gsi = gsi_for_stmt (g);
+ gsi_prev (&gsi);
+ if (gsi_end_p (gsi))
+ return NULL;
+
+ g = gsi_stmt (gsi);
+ if (gimple_call_internal_p (g, IFN_LOOP_DIST_ALIAS))
+ return g;
+ return NULL;
+}
+
+/* Fold loop internal call G like IFN_LOOP_VECTORIZED/IFN_LOOP_DIST_ALIAS
+ to VALUE and update any immediate uses of it's LHS. */
+
+void
+fold_loop_internal_call (gimple *g, tree value)
+{
+ tree lhs = gimple_call_lhs (g);
+ use_operand_p use_p;
+ imm_use_iterator iter;
+ gimple *use_stmt;
+ gimple_stmt_iterator gsi = gsi_for_stmt (g);
+
+ update_call_from_tree (&gsi, value);
+ FOR_EACH_IMM_USE_STMT (use_stmt, iter, lhs)
+ {
+ FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
+ SET_USE (use_p, value);
+ update_stmt (use_stmt);
+ }
+}
+
/* Move a single-entry, single-exit region delimited by ENTRY_BB and
EXIT_BB to function DEST_CFUN. The whole region is replaced by a
single basic block in the original CFG and the new basic block is
@@ -7510,7 +7551,6 @@ move_sese_region_to_fn (struct function
}
}
-
/* Adjust the number of blocks in the tree root of the outlined part. */
get_loop (dest_cfun, 0)->num_nodes = bbs.length () + 2;
@@ -7521,19 +7561,77 @@ move_sese_region_to_fn (struct function
/* Fix up orig_loop_num. If the block referenced in it has been moved
to dest_cfun, update orig_loop_num field, otherwise clear it. */
struct loop *dloop;
+ signed char *moved_orig_loop_num = NULL;
FOR_EACH_LOOP_FN (dest_cfun, dloop, 0)
if (dloop->orig_loop_num)
{
+ if (moved_orig_loop_num == NULL)
+ moved_orig_loop_num
+ = XCNEWVEC (signed char, vec_safe_length (larray));
if ((*larray)[dloop->orig_loop_num] != NULL
&& get_loop (saved_cfun, dloop->orig_loop_num) == NULL)
- dloop->orig_loop_num = (*larray)[dloop->orig_loop_num]->num;
+ {
+ if (moved_orig_loop_num[dloop->orig_loop_num] >= 0
+ && moved_orig_loop_num[dloop->orig_loop_num] < 2)
+ moved_orig_loop_num[dloop->orig_loop_num]++;
+ dloop->orig_loop_num = (*larray)[dloop->orig_loop_num]->num;
+ }
else
- dloop->orig_loop_num = 0;
+ {
+ moved_orig_loop_num[dloop->orig_loop_num] = -1;
+ dloop->orig_loop_num = 0;
+ }
}
- ggc_free (larray);
-
pop_cfun ();
+ if (moved_orig_loop_num)
+ {
+ FOR_EACH_VEC_ELT (bbs, i, bb)
+ {
+ gimple *g = find_loop_dist_alias (bb);
+ if (g == NULL)
+ continue;
+
+ int orig_loop_num = tree_to_shwi (gimple_call_arg (g, 0));
+ gcc_assert (orig_loop_num
+ && (unsigned) orig_loop_num < vec_safe_length (larray));
+ if (moved_orig_loop_num[orig_loop_num] == 2)
+ {
+ /* If we have moved both loops with this orig_loop_num into
+ dest_cfun and the LOOP_DIST_ALIAS call is being moved there
+ too, update the first argument. */
+ gcc_assert ((*larray)[dloop->orig_loop_num] != NULL
+ && (get_loop (saved_cfun, dloop->orig_loop_num)
+ == NULL));
+ tree t = build_int_cst (integer_type_node,
+ (*larray)[dloop->orig_loop_num]->num);
+ gimple_call_set_arg (g, 0, t);
+ update_stmt (g);
+ /* Make sure the following loop will not update it. */
+ moved_orig_loop_num[orig_loop_num] = 0;
+ }
+ else
+ /* Otherwise at least one of the loops stayed in saved_cfun.
+ Remove the LOOP_DIST_ALIAS call. */
+ fold_loop_internal_call (g, gimple_call_arg (g, 1));
+ }
+ FOR_EACH_BB_FN (bb, saved_cfun)
+ {
+ gimple *g = find_loop_dist_alias (bb);
+ if (g == NULL)
+ continue;
+ int orig_loop_num = tree_to_shwi (gimple_call_arg (g, 0));
+ gcc_assert (orig_loop_num
+ && (unsigned) orig_loop_num < vec_safe_length (larray));
+ if (moved_orig_loop_num[orig_loop_num])
+ /* LOOP_DIST_ALIAS call remained in saved_cfun, if at least one
+ of the corresponding loops was moved, remove it. */
+ fold_loop_internal_call (g, gimple_call_arg (g, 1));
+ }
+ XDELETEVEC (moved_orig_loop_num);
+ }
+ ggc_free (larray);
+
/* Move blocks from BBS into DEST_CFUN. */
gcc_assert (bbs.length () >= 2);
after = dest_cfun->cfg->x_entry_block_ptr;
--- gcc/testsuite/gcc.dg/graphite/pr83359.c.jj 2017-12-11 11:43:10.433737382
+0100
+++ gcc/testsuite/gcc.dg/graphite/pr83359.c 2017-12-11 11:43:01.000000000
+0100
@@ -0,0 +1,40 @@
+/* PR tree-optimization/83359 */
+/* { dg-do compile { target pthread } } */
+/* { dg-options "-O3 -floop-parallelize-all -ftree-parallelize-loops=2" } */
+
+int a, b, c;
+
+void
+foo (int x, int y)
+{
+ int *d = &a;
+ int *e = &x;
+
+ for (a = 0; a < 1; ++a)
+ d = &x;
+
+ while (b < 10)
+ {
+ for (b = 0; b < 1; ++b)
+ if (x == 0)
+ while (x < 1)
+ ++x;
+ else
+ while (x < 1)
+ {
+ d = &y;
+ ++x;
+ }
+ ++b;
+ }
+
+ for (;;)
+ for (c = 0; c < 2; ++c)
+ {
+ if (*d != 0)
+ a = *e;
+
+ e = &b;
+ y = 0;
+ }
+}
Jakub
