tree-vect-loop.c (vect_is_slp_reduction): Remove.

2019-09-19  Richard Biener  <rguenther@suse.de>

	* tree-vect-loop.c (vect_is_slp_reduction): Remove.
	(check_reduction_path): New overload having the path as result.
	(vect_is_simple_reduction): From the detected reduction
	path build a SLP reduction chain if possible.

From-SVN: r275972
This commit is contained in:
Richard Biener 2019-09-19 17:19:31 +00:00 committed by Richard Biener
parent 54dc857754
commit b3c4d0dd30
2 changed files with 54 additions and 172 deletions

View File

@ -1,3 +1,10 @@
2019-09-19 Richard Biener <rguenther@suse.de>
* tree-vect-loop.c (vect_is_slp_reduction): Remove.
(check_reduction_path): New overload having the path as result.
(vect_is_simple_reduction): From the detected reduction
path build a SLP reduction chain if possible.
2019-09-19 Richard Biener <rguenther@suse.de>
PR target/91814

View File

@ -2541,163 +2541,6 @@ vect_valid_reduction_input_p (stmt_vec_info def_stmt_info)
&& !is_loop_header_bb_p (gimple_bb (def_stmt_info->stmt))));
}
/* Detect SLP reduction of the form:
#a1 = phi <a5, a0>
a2 = operation (a1)
a3 = operation (a2)
a4 = operation (a3)
a5 = operation (a4)
#a = phi <a5>
PHI is the reduction phi node (#a1 = phi <a5, a0> above)
FIRST_STMT is the first reduction stmt in the chain
(a2 = operation (a1)).
Return TRUE if a reduction chain was detected. */
static bool
vect_is_slp_reduction (loop_vec_info loop_info, gimple *phi,
gimple *first_stmt)
{
class loop *loop = (gimple_bb (phi))->loop_father;
class loop *vect_loop = LOOP_VINFO_LOOP (loop_info);
enum tree_code code;
gimple *loop_use_stmt = NULL;
stmt_vec_info use_stmt_info;
tree lhs;
imm_use_iterator imm_iter;
use_operand_p use_p;
int nloop_uses, size = 0, n_out_of_loop_uses;
bool found = false;
if (loop != vect_loop)
return false;
auto_vec<stmt_vec_info, 8> reduc_chain;
lhs = PHI_RESULT (phi);
code = gimple_assign_rhs_code (first_stmt);
while (1)
{
nloop_uses = 0;
n_out_of_loop_uses = 0;
FOR_EACH_IMM_USE_FAST (use_p, imm_iter, lhs)
{
gimple *use_stmt = USE_STMT (use_p);
if (is_gimple_debug (use_stmt))
continue;
/* Check if we got back to the reduction phi. */
if (use_stmt == phi)
{
loop_use_stmt = use_stmt;
found = true;
break;
}
if (flow_bb_inside_loop_p (loop, gimple_bb (use_stmt)))
{
loop_use_stmt = use_stmt;
nloop_uses++;
}
else
n_out_of_loop_uses++;
/* There are can be either a single use in the loop or two uses in
phi nodes. */
if (nloop_uses > 1 || (n_out_of_loop_uses && nloop_uses))
return false;
}
if (found)
break;
/* We reached a statement with no loop uses. */
if (nloop_uses == 0)
return false;
/* This is a loop exit phi, and we haven't reached the reduction phi. */
if (gimple_code (loop_use_stmt) == GIMPLE_PHI)
return false;
if (!is_gimple_assign (loop_use_stmt)
|| code != gimple_assign_rhs_code (loop_use_stmt)
|| !flow_bb_inside_loop_p (loop, gimple_bb (loop_use_stmt)))
return false;
/* Insert USE_STMT into reduction chain. */
use_stmt_info = loop_info->lookup_stmt (loop_use_stmt);
reduc_chain.safe_push (use_stmt_info);
lhs = gimple_assign_lhs (loop_use_stmt);
size++;
}
if (!found || loop_use_stmt != phi || size < 2)
return false;
/* Swap the operands, if needed, to make the reduction operand be the second
operand. */
lhs = PHI_RESULT (phi);
for (unsigned i = 0; i < reduc_chain.length (); ++i)
{
gassign *next_stmt = as_a <gassign *> (reduc_chain[i]->stmt);
if (gimple_assign_rhs2 (next_stmt) == lhs)
{
tree op = gimple_assign_rhs1 (next_stmt);
stmt_vec_info def_stmt_info = loop_info->lookup_def (op);
/* Check that the other def is either defined in the loop
("vect_internal_def"), or it's an induction (defined by a
loop-header phi-node). */
if (def_stmt_info
&& flow_bb_inside_loop_p (loop, gimple_bb (def_stmt_info->stmt))
&& vect_valid_reduction_input_p (def_stmt_info))
{
lhs = gimple_assign_lhs (next_stmt);
continue;
}
return false;
}
else
{
gcc_assert (gimple_assign_rhs1 (next_stmt) == lhs);
tree op = gimple_assign_rhs2 (next_stmt);
stmt_vec_info def_stmt_info = loop_info->lookup_def (op);
/* Check that the other def is either defined in the loop
("vect_internal_def"), or it's an induction (defined by a
loop-header phi-node). */
if (def_stmt_info
&& flow_bb_inside_loop_p (loop, gimple_bb (def_stmt_info->stmt))
&& vect_valid_reduction_input_p (def_stmt_info))
{
lhs = gimple_assign_lhs (next_stmt);
continue;
}
return false;
}
}
/* Build up the actual chain. */
for (unsigned i = 0; i < reduc_chain.length () - 1; ++i)
{
REDUC_GROUP_FIRST_ELEMENT (reduc_chain[i]) = reduc_chain[0];
REDUC_GROUP_NEXT_ELEMENT (reduc_chain[i]) = reduc_chain[i+1];
}
REDUC_GROUP_FIRST_ELEMENT (reduc_chain.last ()) = reduc_chain[0];
REDUC_GROUP_NEXT_ELEMENT (reduc_chain.last ()) = NULL;
/* Save the chain for further analysis in SLP detection. */
LOOP_VINFO_REDUCTION_CHAINS (loop_info).safe_push (reduc_chain[0]);
REDUC_GROUP_SIZE (reduc_chain[0]) = size;
return true;
}
/* Return true if we need an in-order reduction for operation CODE
on type TYPE. NEED_WRAPPING_INTEGRAL_OVERFLOW is true if integer
overflow must wrap. */
@ -2738,11 +2581,11 @@ needs_fold_left_reduction_p (tree type, tree_code code,
/* Return true if the reduction PHI in LOOP with latch arg LOOP_ARG and
reduction operation CODE has a handled computation expression. */
bool
static bool
check_reduction_path (dump_user_location_t loc, loop_p loop, gphi *phi,
tree loop_arg, enum tree_code code)
tree loop_arg, enum tree_code code,
vec<std::pair<ssa_op_iter, use_operand_p> > &path)
{
auto_vec<std::pair<ssa_op_iter, use_operand_p> > path;
auto_bitmap visited;
tree lookfor = PHI_RESULT (phi);
ssa_op_iter curri;
@ -2839,6 +2682,15 @@ pop:
return ! fail && ! neg;
}
bool
check_reduction_path (dump_user_location_t loc, loop_p loop, gphi *phi,
tree loop_arg, enum tree_code code)
{
auto_vec<std::pair<ssa_op_iter, use_operand_p> > path;
return check_reduction_path (loc, loop, phi, loop_arg, code, path);
}
/* Function vect_is_simple_reduction
@ -3223,23 +3075,46 @@ vect_is_simple_reduction (loop_vec_info loop_info, stmt_vec_info phi_info,
return def_stmt_info;
}
/* Try to find SLP reduction chain. */
if (! nested_in_vect_loop
&& code != COND_EXPR
&& orig_code != MINUS_EXPR
&& vect_is_slp_reduction (loop_info, phi, def_stmt))
/* Look for the expression computing loop_arg from loop PHI result. */
auto_vec<std::pair<ssa_op_iter, use_operand_p> > path;
if (check_reduction_path (vect_location, loop, phi, loop_arg, code,
path))
{
if (dump_enabled_p ())
report_vect_op (MSG_NOTE, def_stmt,
"reduction: detected reduction chain: ");
/* Try building an SLP reduction chain for which the additional
restriction is that all operations in the chain are the same. */
auto_vec<stmt_vec_info, 8> reduc_chain;
unsigned i;
for (i = path.length () - 1; i >= 1; --i)
{
gimple *stmt = USE_STMT (path[i].second);
if (gimple_assign_rhs_code (stmt) != code)
break;
reduc_chain.safe_push (loop_info->lookup_stmt (stmt));
}
if (i == 0
&& ! nested_in_vect_loop
&& code != COND_EXPR)
{
for (unsigned i = 0; i < reduc_chain.length () - 1; ++i)
{
REDUC_GROUP_FIRST_ELEMENT (reduc_chain[i]) = reduc_chain[0];
REDUC_GROUP_NEXT_ELEMENT (reduc_chain[i]) = reduc_chain[i+1];
}
REDUC_GROUP_FIRST_ELEMENT (reduc_chain.last ()) = reduc_chain[0];
REDUC_GROUP_NEXT_ELEMENT (reduc_chain.last ()) = NULL;
/* Save the chain for further analysis in SLP detection. */
LOOP_VINFO_REDUCTION_CHAINS (loop_info).safe_push (reduc_chain[0]);
REDUC_GROUP_SIZE (reduc_chain[0]) = reduc_chain.length ();
if (dump_enabled_p ())
report_vect_op (MSG_NOTE, def_stmt,
"reduction: detected reduction chain: ");
}
return def_stmt_info;
}
/* Look for the expression computing loop_arg from loop PHI result. */
if (check_reduction_path (vect_location, loop, phi, loop_arg, code))
return def_stmt_info;
if (dump_enabled_p ())
{
report_vect_op (MSG_MISSED_OPTIMIZATION, def_stmt,