static lambda_lattice lambda_lattice_compute_base (lambda_loopnest);
static tree find_induction_var_from_exit_cond (struct loop *);
+static bool can_convert_to_perfect_nest (struct loop *);
/* Create a new lambda body vector. */
/* Compute the least common multiple of two numbers A and B . */
-static int
-lcm (int a, int b)
+int
+least_common_multiple (int a, int b)
{
return (abs (a) * abs (b) / gcd (a, b));
}
{
if (A[k][i] < 0)
{
- multiple = lcm (A[j][i], A[k][i]);
+ multiple = least_common_multiple (A[j][i], A[k][i]);
f1 = multiple / A[j][i];
f2 = -1 * multiple / A[k][i];
4. Multiply the composed transformation matrix times the matrix form of the
loop.
5. Transform the newly created matrix (from step 4) back into a loop nest
- using fourier motzkin elimination to figure out the bounds. */
+ using Fourier-Motzkin elimination to figure out the bounds. */
static lambda_loopnest
lambda_compute_auxillary_space (lambda_loopnest nest,
lambda_matrix_add_mc (B, 1, B1, -1, B1, size, invariants);
/* Now compute the auxiliary space bounds by first inverting U, multiplying
- it by A1, then performing fourier motzkin. */
+ it by A1, then performing Fourier-Motzkin. */
invertedtrans = lambda_matrix_new (depth, depth);
lambda_loopnest
gcc_loopnest_to_lambda_loopnest (struct loops *currloops,
- struct loop * loop_nest,
+ struct loop *loop_nest,
VEC(tree,heap) **inductionvars,
- VEC(tree,heap) **invariants,
- bool need_perfect_nest)
+ VEC(tree,heap) **invariants)
{
lambda_loopnest ret = NULL;
- struct loop *temp;
- int depth = 0;
+ struct loop *temp = loop_nest;
+ int depth = depth_of_nest (loop_nest);
size_t i;
VEC(lambda_loop,heap) *loops = NULL;
VEC(tree,heap) *uboundvars = NULL;
VEC(int,heap) *steps = NULL;
lambda_loop newloop;
tree inductionvar = NULL;
-
- depth = depth_of_nest (loop_nest);
- temp = loop_nest;
+ bool perfect_nest = perfect_nest_p (loop_nest);
+
+ if (!perfect_nest && !can_convert_to_perfect_nest (loop_nest))
+ goto fail;
+
while (temp)
{
newloop = gcc_loop_to_lambda_loop (temp, depth, invariants,
&lboundvars, &uboundvars,
&steps);
if (!newloop)
- return NULL;
+ goto fail;
+
VEC_safe_push (tree, heap, *inductionvars, inductionvar);
VEC_safe_push (lambda_loop, heap, loops, newloop);
temp = temp->inner;
}
- if (need_perfect_nest)
+
+ if (!perfect_nest)
{
if (!perfect_nestify (currloops, loop_nest,
lboundvars, uboundvars, steps, *inductionvars))
fprintf (dump_file,
"Successfully converted loop nest to perfect loop nest.\n");
}
+
ret = lambda_loopnest_new (depth, 2 * depth);
+
for (i = 0; VEC_iterate (lambda_loop, loops, i, newloop); i++)
LN_LOOPS (ret)[i] = newloop;
+
fail:
VEC_free (lambda_loop, heap, loops);
VEC_free (tree, heap, uboundvars);
/* Create a statement list and a linear expression temporary. */
stmts = alloc_stmt_list ();
resvar = create_tmp_var (type, "lbvtmp");
- add_referenced_tmp_var (resvar);
+ add_referenced_var (resvar);
/* Start at 0. */
stmt = build2 (MODIFY_EXPR, void_type_node, resvar, integer_zero_node);
/* Create a statement list and a linear expression temporary. */
stmts = alloc_stmt_list ();
resvar = create_tmp_var (type, "lletmp");
- add_referenced_tmp_var (resvar);
+ add_referenced_var (resvar);
/* Build up the linear expressions, and put the variable representing the
result in the results array. */
/* First, build the new induction variable temporary */
ivvar = create_tmp_var (type, "lnivtmp");
- add_referenced_tmp_var (ivvar);
+ add_referenced_var (ivvar);
VEC_safe_push (tree, heap, new_ivs, ivvar);
type,
new_ivs,
invariants, MIN_EXPR, &stmts);
- exit = temp->single_exit;
+ exit = single_exit (temp);
exitcond = get_loop_exit_condition (temp);
bb = bb_for_stmt (exitcond);
bsi = bsi_start (bb);
for (i = 0; VEC_iterate (tree, old_ivs, i, oldiv); i++)
{
imm_use_iterator imm_iter;
- use_operand_p imm_use;
+ use_operand_p use_p;
tree oldiv_def;
tree oldiv_stmt = SSA_NAME_DEF_STMT (oldiv);
+ tree stmt;
if (TREE_CODE (oldiv_stmt) == PHI_NODE)
oldiv_def = PHI_RESULT (oldiv_stmt);
oldiv_def = SINGLE_SSA_TREE_OPERAND (oldiv_stmt, SSA_OP_DEF);
gcc_assert (oldiv_def != NULL_TREE);
- FOR_EACH_IMM_USE_SAFE (imm_use, imm_iter, oldiv_def)
- {
- tree stmt = USE_STMT (imm_use);
- use_operand_p use_p;
- ssa_op_iter iter;
+ FOR_EACH_IMM_USE_STMT (stmt, imm_iter, oldiv_def)
+ {
+ tree newiv, stmts;
+ lambda_body_vector lbv, newlbv;
+
gcc_assert (TREE_CODE (stmt) != PHI_NODE);
- FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter, SSA_OP_USE)
- {
- if (USE_FROM_PTR (use_p) == oldiv)
- {
- tree newiv, stmts;
- lambda_body_vector lbv, newlbv;
- /* Compute the new expression for the induction
- variable. */
- depth = VEC_length (tree, new_ivs);
- lbv = lambda_body_vector_new (depth);
- LBV_COEFFICIENTS (lbv)[i] = 1;
-
- newlbv = lambda_body_vector_compute_new (transform, lbv);
-
- newiv = lbv_to_gcc_expression (newlbv, TREE_TYPE (oldiv),
- new_ivs, &stmts);
- bsi = bsi_for_stmt (stmt);
- /* Insert the statements to build that
- expression. */
- bsi_insert_before (&bsi, stmts, BSI_SAME_STMT);
- propagate_value (use_p, newiv);
- update_stmt (stmt);
-
- }
- }
+
+ /* Compute the new expression for the induction
+ variable. */
+ depth = VEC_length (tree, new_ivs);
+ lbv = lambda_body_vector_new (depth);
+ LBV_COEFFICIENTS (lbv)[i] = 1;
+
+ newlbv = lambda_body_vector_compute_new (transform, lbv);
+
+ newiv = lbv_to_gcc_expression (newlbv, TREE_TYPE (oldiv),
+ new_ivs, &stmts);
+ bsi = bsi_for_stmt (stmt);
+ /* Insert the statements to build that
+ expression. */
+ bsi_insert_before (&bsi, stmts, BSI_SAME_STMT);
+
+ FOR_EACH_IMM_USE_ON_STMT (use_p, imm_iter)
+ propagate_value (use_p, newiv);
+ update_stmt (stmt);
}
}
VEC_free (tree, heap, new_ivs);
return true;
}
-/* Replace the USES of X in STMT, or uses with the same step as X with Y. */
+/* Replace the USES of X in STMT, or uses with the same step as X with Y.
+ YINIT is the initial value of Y, REPLACEMENTS is a hash table to
+ avoid creating duplicate temporaries and FIRSTBSI is statement
+ iterator where new temporaries should be inserted at the beginning
+ of body basic block. */
static void
replace_uses_equiv_to_x_with_y (struct loop *loop, tree stmt, tree x,
- int xstep, tree y)
+ int xstep, tree y, tree yinit,
+ htab_t replacements,
+ block_stmt_iterator *firstbsi)
{
ssa_op_iter iter;
use_operand_p use_p;
{
tree use = USE_FROM_PTR (use_p);
tree step = NULL_TREE;
- tree access_fn = NULL_TREE;
-
-
- access_fn = instantiate_parameters
- (loop, analyze_scalar_evolution (loop, use));
- if (access_fn != NULL_TREE && access_fn != chrec_dont_know)
- step = evolution_part_in_loop_num (access_fn, loop->num);
- if ((step && step != chrec_dont_know
- && TREE_CODE (step) == INTEGER_CST
- && int_cst_value (step) == xstep)
- || USE_FROM_PTR (use_p) == x)
- SET_USE (use_p, y);
- }
-}
+ tree scev, init, val, var, setstmt;
+ struct tree_map *h, in;
+ void **loc;
-/* Return TRUE if STMT uses tree OP in it's uses. */
+ /* Replace uses of X with Y right away. */
+ if (use == x)
+ {
+ SET_USE (use_p, y);
+ continue;
+ }
-static bool
-stmt_uses_op (tree stmt, tree op)
-{
- ssa_op_iter iter;
- tree use;
+ scev = instantiate_parameters (loop,
+ analyze_scalar_evolution (loop, use));
- FOR_EACH_SSA_TREE_OPERAND (use, stmt, iter, SSA_OP_USE)
- {
- if (use == op)
- return true;
+ if (scev == NULL || scev == chrec_dont_know)
+ continue;
+
+ step = evolution_part_in_loop_num (scev, loop->num);
+ if (step == NULL
+ || step == chrec_dont_know
+ || TREE_CODE (step) != INTEGER_CST
+ || int_cst_value (step) != xstep)
+ continue;
+
+ /* Use REPLACEMENTS hash table to cache already created
+ temporaries. */
+ in.hash = htab_hash_pointer (use);
+ in.from = use;
+ h = htab_find_with_hash (replacements, &in, in.hash);
+ if (h != NULL)
+ {
+ SET_USE (use_p, h->to);
+ continue;
+ }
+
+ /* USE which has the same step as X should be replaced
+ with a temporary set to Y + YINIT - INIT. */
+ init = initial_condition_in_loop_num (scev, loop->num);
+ gcc_assert (init != NULL && init != chrec_dont_know);
+ if (TREE_TYPE (use) == TREE_TYPE (y))
+ {
+ val = fold_build2 (MINUS_EXPR, TREE_TYPE (y), init, yinit);
+ val = fold_build2 (PLUS_EXPR, TREE_TYPE (y), y, val);
+ if (val == y)
+ {
+ /* If X has the same type as USE, the same step
+ and same initial value, it can be replaced by Y. */
+ SET_USE (use_p, y);
+ continue;
+ }
+ }
+ else
+ {
+ val = fold_build2 (MINUS_EXPR, TREE_TYPE (y), y, yinit);
+ val = fold_convert (TREE_TYPE (use), val);
+ val = fold_build2 (PLUS_EXPR, TREE_TYPE (use), val, init);
+ }
+
+ /* Create a temporary variable and insert it at the beginning
+ of the loop body basic block, right after the PHI node
+ which sets Y. */
+ var = create_tmp_var (TREE_TYPE (use), "perfecttmp");
+ add_referenced_var (var);
+ val = force_gimple_operand_bsi (firstbsi, val, false, NULL);
+ setstmt = build2 (MODIFY_EXPR, void_type_node, var, val);
+ var = make_ssa_name (var, setstmt);
+ TREE_OPERAND (setstmt, 0) = var;
+ bsi_insert_before (firstbsi, setstmt, BSI_SAME_STMT);
+ update_stmt (setstmt);
+ SET_USE (use_p, var);
+ h = ggc_alloc (sizeof (struct tree_map));
+ h->hash = in.hash;
+ h->from = use;
+ h->to = var;
+ loc = htab_find_slot_with_hash (replacements, h, in.hash, INSERT);
+ gcc_assert ((*(struct tree_map **)loc) == NULL);
+ *(struct tree_map **) loc = h;
}
- return false;
}
/* Return true if STMT is an exit PHI for LOOP */
if (TREE_CODE (stmt) != PHI_NODE
|| PHI_NUM_ARGS (stmt) != 1
- || bb_for_stmt (stmt) != loop->single_exit->dest)
+ || bb_for_stmt (stmt) != single_exit (loop)->dest)
return false;
return true;
-/* Return TRUE if LOOP is an imperfect nest that we can convert to a perfect
- one. LOOPIVS is a vector of induction variables, one per loop.
- ATM, we only handle imperfect nests of depth 2, where all of the statements
- occur after the inner loop. */
+/* Return TRUE if LOOP is an imperfect nest that we can convert to a
+ perfect one. At the moment, we only handle imperfect nests of
+ depth 2, where all of the statements occur after the inner loop. */
static bool
-can_convert_to_perfect_nest (struct loop *loop,
- VEC(tree,heap) *loopivs)
+can_convert_to_perfect_nest (struct loop *loop)
{
basic_block *bbs;
tree exit_condition, phi;
{
for (bsi = bsi_start (bbs[i]); !bsi_end_p (bsi); bsi_next (&bsi))
{
- size_t j;
tree stmt = bsi_stmt (bsi);
- tree iv;
-
+
if (stmt == exit_condition
|| not_interesting_stmt (stmt)
|| stmt_is_bumper_for_loop (loop, stmt))
continue;
- /* If the statement uses inner loop ivs, we == screwed. */
- for (j = 1; VEC_iterate (tree, loopivs, j, iv); j++)
- if (stmt_uses_op (stmt, iv))
- goto fail;
-
+
/* If this is a scalar operation that can be put back
into the inner loop, or after the inner loop, through
copying, then do so. This works on the theory that
win we get from rearranging the memory walk
the loop is doing so that it has better
cache behavior. */
- if (TREE_CODE (stmt) == MODIFY_EXPR
- && (can_put_in_inner_loop (loop->inner, stmt)
- || can_put_after_inner_loop (loop, stmt)))
- continue;
+ if (TREE_CODE (stmt) == MODIFY_EXPR)
+ {
+ use_operand_p use_a, use_b;
+ imm_use_iterator imm_iter;
+ ssa_op_iter op_iter, op_iter1;
+ tree op0 = TREE_OPERAND (stmt, 0);
+ tree scev = instantiate_parameters
+ (loop, analyze_scalar_evolution (loop, op0));
+
+ /* If the IV is simple, it can be duplicated. */
+ if (!automatically_generated_chrec_p (scev))
+ {
+ tree step = evolution_part_in_loop_num (scev, loop->num);
+ if (step && step != chrec_dont_know
+ && TREE_CODE (step) == INTEGER_CST)
+ continue;
+ }
+
+ /* The statement should not define a variable used
+ in the inner loop. */
+ if (TREE_CODE (op0) == SSA_NAME)
+ FOR_EACH_IMM_USE_FAST (use_a, imm_iter, op0)
+ if (bb_for_stmt (USE_STMT (use_a))->loop_father
+ == loop->inner)
+ goto fail;
+
+ FOR_EACH_SSA_USE_OPERAND (use_a, stmt, op_iter, SSA_OP_USE)
+ {
+ tree node, op = USE_FROM_PTR (use_a);
+
+ /* The variables should not be used in both loops. */
+ FOR_EACH_IMM_USE_FAST (use_b, imm_iter, op)
+ if (bb_for_stmt (USE_STMT (use_b))->loop_father
+ == loop->inner)
+ goto fail;
+
+ /* The statement should not use the value of a
+ scalar that was modified in the loop. */
+ node = SSA_NAME_DEF_STMT (op);
+ if (TREE_CODE (node) == PHI_NODE)
+ FOR_EACH_PHI_ARG (use_b, node, op_iter1, SSA_OP_USE)
+ {
+ tree arg = USE_FROM_PTR (use_b);
+
+ if (TREE_CODE (arg) == SSA_NAME)
+ {
+ tree arg_stmt = SSA_NAME_DEF_STMT (arg);
+
+ if (bb_for_stmt (arg_stmt)->loop_father
+ == loop->inner)
+ goto fail;
+ }
+ }
+ }
+
+ if (can_put_in_inner_loop (loop->inner, stmt)
+ || can_put_after_inner_loop (loop, stmt))
+ continue;
+ }
/* Otherwise, if the bb of a statement we care about isn't
dominated by the header of the inner loop, then we can't
/* We also need to make sure the loop exit only has simple copy phis in it,
otherwise we don't know how to transform it into a perfect nest right
now. */
- exitdest = loop->single_exit->dest;
+ exitdest = single_exit (loop)->dest;
for (phi = phi_nodes (exitdest); phi; phi = PHI_CHAIN (phi))
if (PHI_NUM_ARGS (phi) != 1)
tree then_label, else_label, cond_stmt;
basic_block preheaderbb, headerbb, bodybb, latchbb, olddest;
int i;
- block_stmt_iterator bsi;
+ block_stmt_iterator bsi, firstbsi;
bool insert_after;
edge e;
struct loop *newloop;
tree stmt;
tree oldivvar, ivvar, ivvarinced;
VEC(tree,heap) *phis = NULL;
+ htab_t replacements = NULL;
- if (!can_convert_to_perfect_nest (loop, loopivs))
- return false;
-
- /* Create the new loop */
-
- olddest = loop->single_exit->dest;
- preheaderbb = loop_split_edge_with (loop->single_exit, NULL);
+ /* Create the new loop. */
+ olddest = single_exit (loop)->dest;
+ preheaderbb = split_edge (single_exit (loop));
headerbb = create_empty_bb (EXIT_BLOCK_PTR->prev_bb);
/* Push the exit phi nodes that we are moving. */
newloop = duplicate_loop (loops, loop, olddest->loop_father);
newloop->header = headerbb;
newloop->latch = latchbb;
- newloop->single_exit = e;
+ set_single_exit (newloop, e);
add_bb_to_loop (latchbb, newloop);
add_bb_to_loop (bodybb, newloop);
add_bb_to_loop (headerbb, newloop);
set_immediate_dominator (CDI_DOMINATORS, bodybb, headerbb);
set_immediate_dominator (CDI_DOMINATORS, headerbb, preheaderbb);
set_immediate_dominator (CDI_DOMINATORS, preheaderbb,
- loop->single_exit->src);
+ single_exit (loop)->src);
set_immediate_dominator (CDI_DOMINATORS, latchbb, bodybb);
set_immediate_dominator (CDI_DOMINATORS, olddest, bodybb);
/* Create the new iv. */
oldivvar = VEC_index (tree, loopivs, 0);
ivvar = create_tmp_var (TREE_TYPE (oldivvar), "perfectiv");
- add_referenced_tmp_var (ivvar);
+ add_referenced_var (ivvar);
standard_iv_increment_position (newloop, &bsi, &insert_after);
create_iv (VEC_index (tree, lbounds, 0),
build_int_cst (TREE_TYPE (oldivvar), VEC_index (int, steps, 0)),
exit_condition = get_loop_exit_condition (newloop);
uboundvar = create_tmp_var (integer_type_node, "uboundvar");
- add_referenced_tmp_var (uboundvar);
+ add_referenced_var (uboundvar);
stmt = build2 (MODIFY_EXPR, void_type_node, uboundvar,
VEC_index (tree, ubounds, 0));
uboundvar = make_ssa_name (uboundvar, stmt);
uboundvar,
ivvarinced);
update_stmt (exit_condition);
+ replacements = htab_create_ggc (20, tree_map_hash,
+ tree_map_eq, NULL);
bbs = get_loop_body_in_dom_order (loop);
/* Now move the statements, and replace the induction variable in the moved
statements with the correct loop induction variable. */
oldivvar = VEC_index (tree, loopivs, 0);
+ firstbsi = bsi_start (bodybb);
for (i = loop->num_nodes - 1; i >= 0 ; i--)
{
block_stmt_iterator tobsi = bsi_last (bodybb);
if (dominated_by_p (CDI_DOMINATORS, loop->inner->header, bbs[i]))
{
- for (bsi = bsi_last (bbs[i]); !bsi_end_p (bsi);)
+ block_stmt_iterator header_bsi
+ = bsi_after_labels (loop->inner->header);
+
+ for (bsi = bsi_start (bbs[i]); !bsi_end_p (bsi);)
{
- use_operand_p use_p;
- imm_use_iterator imm_iter;
tree stmt = bsi_stmt (bsi);
if (stmt == exit_condition
|| not_interesting_stmt (stmt)
|| stmt_is_bumper_for_loop (loop, stmt))
{
- if (!bsi_end_p (bsi))
- bsi_prev (&bsi);
+ bsi_next (&bsi);
continue;
}
-
- /* Make copies of this statement to put it back next
- to its uses. */
- FOR_EACH_IMM_USE_SAFE (use_p, imm_iter,
- TREE_OPERAND (stmt, 0))
- {
- tree imm_stmt = USE_STMT (use_p);
- if (!exit_phi_for_loop_p (loop->inner, imm_stmt))
- {
- block_stmt_iterator tobsi;
- tree newname;
- tree newstmt;
-
- newstmt = unshare_expr (stmt);
- tobsi = bsi_after_labels (bb_for_stmt (imm_stmt));
- newname = TREE_OPERAND (newstmt, 0);
- newname = SSA_NAME_VAR (newname);
- newname = make_ssa_name (newname, newstmt);
- TREE_OPERAND (newstmt, 0) = newname;
- SET_USE (use_p, TREE_OPERAND (newstmt, 0));
- bsi_insert_before (&tobsi, newstmt, BSI_SAME_STMT);
- update_stmt (newstmt);
- update_stmt (imm_stmt);
- }
- }
- if (!bsi_end_p (bsi))
- bsi_prev (&bsi);
+
+ bsi_move_before (&bsi, &header_bsi);
}
}
else
continue;
}
- replace_uses_equiv_to_x_with_y (loop, stmt,
- oldivvar,
- VEC_index (int, steps, 0),
- ivvar);
+ replace_uses_equiv_to_x_with_y
+ (loop, stmt, oldivvar, VEC_index (int, steps, 0), ivvar,
+ VEC_index (tree, lbounds, 0), replacements, &firstbsi);
+
bsi_move_before (&bsi, &tobsi);
/* If the statement has any virtual operands, they may
}
free (bbs);
+ htab_delete (replacements);
return perfect_nest_p (loop);
}