vect: Use generalised accessors to build SLP nodes

This patch adds:

- gimple_num_args
- gimple_arg
- gimple_arg_ptr

for accessing rhs operands of an assignment, call or PHI.  This is
similar to the existing gimple_get_lhs.

I guess there's a danger that these routines could be overused,
such as in cases where gimple_assign_rhs1 etc. would be more
appropriate.  I think the routines are still worth having though.
These days, most new operations are added as internal functions rather
than tree codes, so it's useful to be able to handle assignments and
calls in a consistent way.

The patch also generalises the way that SLP child nodes map
to gimple stmt operands.  This is useful for later patches.

gcc/
	* gimple.h (gimple_num_args, gimple_arg, gimple_arg_ptr): New
	functions.
	* tree-vect-slp.c (cond_expr_maps, arg2_map): New variables.
	(vect_get_operand_map): New function.
	(vect_get_and_check_slp_defs): Fix outdated comment.
	Use vect_get_operand_map and new gimple argument accessors.
	(vect_build_slp_tree_2): Likewise.
This commit is contained in:
Richard Sandiford 2021-11-30 09:52:28 +00:00
parent 8de7958fbd
commit 6f798618c0
2 changed files with 115 additions and 73 deletions

View File

@ -4692,6 +4692,44 @@ gimple_phi_arg_has_location (const gphi *phi, size_t i)
return gimple_phi_arg_location (phi, i) != UNKNOWN_LOCATION;
}
/* Return the number of arguments that can be accessed by gimple_arg. */
static inline unsigned
gimple_num_args (const gimple *gs)
{
if (auto phi = dyn_cast<const gphi *> (gs))
return gimple_phi_num_args (phi);
if (auto call = dyn_cast<const gcall *> (gs))
return gimple_call_num_args (call);
return gimple_num_ops (as_a <const gassign *> (gs)) - 1;
}
/* GS must be an assignment, a call, or a PHI.
If it's an assignment, return rhs operand I.
If it's a call, return function argument I.
If it's a PHI, return the value of PHI argument I. */
static inline tree
gimple_arg (const gimple *gs, unsigned int i)
{
if (auto phi = dyn_cast<const gphi *> (gs))
return gimple_phi_arg_def (phi, i);
if (auto call = dyn_cast<const gcall *> (gs))
return gimple_call_arg (call, i);
return gimple_op (as_a <const gassign *> (gs), i + 1);
}
/* Return a pointer to gimple_arg (GS, I). */
static inline tree *
gimple_arg_ptr (gimple *gs, unsigned int i)
{
if (auto phi = dyn_cast<gphi *> (gs))
return gimple_phi_arg_def_ptr (phi, i);
if (auto call = dyn_cast<gcall *> (gs))
return gimple_call_arg_ptr (call, i);
return gimple_op_ptr (as_a <gassign *> (gs), i + 1);
}
/* Return the region number for GIMPLE_RESX RESX_STMT. */

View File

@ -454,15 +454,57 @@ vect_def_types_match (enum vect_def_type dta, enum vect_def_type dtb)
&& (dtb == vect_external_def || dtb == vect_constant_def)));
}
static const int cond_expr_maps[3][5] = {
{ 4, -1, -2, 1, 2 },
{ 4, -2, -1, 1, 2 },
{ 4, -1, -2, 2, 1 }
};
static const int arg2_map[] = { 1, 2 };
/* For most SLP statements, there is a one-to-one mapping between
gimple arguments and child nodes. If that is not true for STMT,
return an array that contains:
- the number of child nodes, followed by
- for each child node, the index of the argument associated with that node.
The special index -1 is the first operand of an embedded comparison and
the special index -2 is the second operand of an embedded comparison.
SWAP is as for vect_get_and_check_slp_defs. */
static const int *
vect_get_operand_map (const gimple *stmt, unsigned char swap = 0)
{
if (auto assign = dyn_cast<const gassign *> (stmt))
{
if (gimple_assign_rhs_code (assign) == COND_EXPR
&& COMPARISON_CLASS_P (gimple_assign_rhs1 (assign)))
return cond_expr_maps[swap];
}
gcc_assert (!swap);
if (auto call = dyn_cast<const gcall *> (stmt))
{
if (gimple_call_internal_p (call))
switch (gimple_call_internal_fn (call))
{
case IFN_MASK_LOAD:
return arg2_map;
default:
break;
}
}
return nullptr;
}
/* Get the defs for the rhs of STMT (collect them in OPRNDS_INFO), check that
they are of a valid type and that they match the defs of the first stmt of
the SLP group (stored in OPRNDS_INFO). This function tries to match stmts
by swapping operands of STMTS[STMT_NUM] when possible. Non-zero *SWAP
indicates swap is required for cond_expr stmts. Specifically, *SWAP
by swapping operands of STMTS[STMT_NUM] when possible. Non-zero SWAP
indicates swap is required for cond_expr stmts. Specifically, SWAP
is 1 if STMT is cond and operands of comparison need to be swapped;
*SWAP is 2 if STMT is cond and code of comparison needs to be inverted.
If there is any operand swap in this function, *SWAP is set to non-zero
value.
SWAP is 2 if STMT is cond and code of comparison needs to be inverted.
If there was a fatal error return -1; if the error could be corrected by
swapping operands of father node of this one, return 1; if everything is
ok return 0. */
@ -477,76 +519,48 @@ vect_get_and_check_slp_defs (vec_info *vinfo, unsigned char swap,
unsigned int i, number_of_oprnds;
enum vect_def_type dt = vect_uninitialized_def;
slp_oprnd_info oprnd_info;
int first_op_idx = 1;
unsigned int commutative_op = -1U;
bool first_op_cond = false;
bool first = stmt_num == 0;
if (!is_a<gcall *> (stmt_info->stmt)
&& !is_a<gassign *> (stmt_info->stmt)
&& !is_a<gphi *> (stmt_info->stmt))
return -1;
number_of_oprnds = gimple_num_args (stmt_info->stmt);
const int *map = vect_get_operand_map (stmt_info->stmt, swap);
if (map)
number_of_oprnds = *map++;
if (gcall *stmt = dyn_cast <gcall *> (stmt_info->stmt))
{
number_of_oprnds = gimple_call_num_args (stmt);
first_op_idx = 3;
if (gimple_call_internal_p (stmt))
{
internal_fn ifn = gimple_call_internal_fn (stmt);
commutative_op = first_commutative_argument (ifn);
/* Masked load, only look at mask. */
if (ifn == IFN_MASK_LOAD)
{
number_of_oprnds = 1;
/* Mask operand index. */
first_op_idx = 5;
}
}
}
else if (gassign *stmt = dyn_cast <gassign *> (stmt_info->stmt))
{
enum tree_code code = gimple_assign_rhs_code (stmt);
number_of_oprnds = gimple_num_ops (stmt) - 1;
/* Swap can only be done for cond_expr if asked to, otherwise we
could result in different comparison code to the first stmt. */
if (code == COND_EXPR
&& COMPARISON_CLASS_P (gimple_assign_rhs1 (stmt)))
{
first_op_cond = true;
number_of_oprnds++;
}
else
commutative_op = commutative_tree_code (code) ? 0U : -1U;
if (commutative_tree_code (gimple_assign_rhs_code (stmt)))
commutative_op = 0;
}
else if (gphi *stmt = dyn_cast <gphi *> (stmt_info->stmt))
number_of_oprnds = gimple_phi_num_args (stmt);
else
return -1;
bool swapped = (swap != 0);
bool backedge = false;
gcc_assert (!swapped || first_op_cond);
enum vect_def_type *dts = XALLOCAVEC (enum vect_def_type, number_of_oprnds);
for (i = 0; i < number_of_oprnds; i++)
{
if (first_op_cond)
{
/* Map indicating how operands of cond_expr should be swapped. */
int maps[3][4] = {{0, 1, 2, 3}, {1, 0, 2, 3}, {0, 1, 3, 2}};
int *map = maps[swap];
if (i < 2)
oprnd = TREE_OPERAND (gimple_op (stmt_info->stmt,
first_op_idx), map[i]);
else
oprnd = gimple_op (stmt_info->stmt, map[i]);
}
else if (gphi *stmt = dyn_cast <gphi *> (stmt_info->stmt))
{
oprnd = gimple_phi_arg_def (stmt, i);
backedge = dominated_by_p (CDI_DOMINATORS,
gimple_phi_arg_edge (stmt, i)->src,
gimple_bb (stmt_info->stmt));
}
int opno = map ? map[i] : int (i);
if (opno < 0)
oprnd = TREE_OPERAND (gimple_arg (stmt_info->stmt, 0), -1 - opno);
else
oprnd = gimple_op (stmt_info->stmt, first_op_idx + (swapped ? !i : i));
{
oprnd = gimple_arg (stmt_info->stmt, opno);
if (gphi *stmt = dyn_cast <gphi *> (stmt_info->stmt))
backedge = dominated_by_p (CDI_DOMINATORS,
gimple_phi_arg_edge (stmt, opno)->src,
gimple_bb (stmt_info->stmt));
}
if (TREE_CODE (oprnd) == VIEW_CONVERT_EXPR)
oprnd = TREE_OPERAND (oprnd, 0);
@ -1140,9 +1154,7 @@ vect_build_slp_tree_1 (vec_info *vinfo, unsigned char *swap,
if (need_same_oprnds)
{
tree other_op1 = (call_stmt
? gimple_call_arg (call_stmt, 1)
: gimple_assign_rhs2 (stmt));
tree other_op1 = gimple_arg (stmt, 1);
if (!operand_equal_p (first_op1, other_op1, 0))
{
if (dump_enabled_p ())
@ -1601,19 +1613,15 @@ vect_build_slp_tree_2 (vec_info *vinfo, slp_tree node,
matches[0] = false;
stmt_vec_info stmt_info = stmts[0];
if (gcall *stmt = dyn_cast <gcall *> (stmt_info->stmt))
nops = gimple_call_num_args (stmt);
else if (gassign *stmt = dyn_cast <gassign *> (stmt_info->stmt))
{
nops = gimple_num_ops (stmt) - 1;
if (gimple_assign_rhs_code (stmt) == COND_EXPR)
nops++;
}
else if (gphi *phi = dyn_cast <gphi *> (stmt_info->stmt))
nops = gimple_phi_num_args (phi);
else
if (!is_a<gcall *> (stmt_info->stmt)
&& !is_a<gassign *> (stmt_info->stmt)
&& !is_a<gphi *> (stmt_info->stmt))
return NULL;
nops = gimple_num_args (stmt_info->stmt);
if (const int *map = vect_get_operand_map (stmt_info->stmt))
nops = map[0];
/* If the SLP node is a PHI (induction or reduction), terminate
the recursion. */
bool *skip_args = XALLOCAVEC (bool, nops);
@ -1684,11 +1692,7 @@ vect_build_slp_tree_2 (vec_info *vinfo, slp_tree node,
&& DR_IS_READ (STMT_VINFO_DATA_REF (stmt_info)))
{
if (gcall *stmt = dyn_cast <gcall *> (stmt_info->stmt))
{
/* Masked load. */
gcc_assert (gimple_call_internal_p (stmt, IFN_MASK_LOAD));
nops = 1;
}
gcc_assert (gimple_call_internal_p (stmt, IFN_MASK_LOAD));
else
{
*max_nunits = this_max_nunits;