tree-scalar-evolution.c [plain text]
#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "tm.h"
#include "ggc.h"
#include "tree.h"
#include "real.h"
#include "rtl.h"
#include "basic-block.h"
#include "diagnostic.h"
#include "tree-flow.h"
#include "tree-dump.h"
#include "timevar.h"
#include "cfgloop.h"
#include "tree-chrec.h"
#include "tree-scalar-evolution.h"
#include "tree-pass.h"
#include "flags.h"
#include "params.h"
static tree analyze_scalar_evolution_1 (struct loop *, tree, tree);
static tree resolve_mixers (struct loop *, tree);
struct scev_info_str
{
tree var;
tree chrec;
};
static unsigned nb_set_scev = 0;
static unsigned nb_get_scev = 0;
tree chrec_not_analyzed_yet;
tree chrec_dont_know;
tree chrec_known;
static bitmap already_instantiated;
static htab_t scalar_evolution_info;
static inline struct scev_info_str *
new_scev_info_str (tree var)
{
struct scev_info_str *res;
res = XNEW (struct scev_info_str);
res->var = var;
res->chrec = chrec_not_analyzed_yet;
return res;
}
static hashval_t
hash_scev_info (const void *elt)
{
return SSA_NAME_VERSION (((struct scev_info_str *) elt)->var);
}
static int
eq_scev_info (const void *e1, const void *e2)
{
const struct scev_info_str *elt1 = (const struct scev_info_str *) e1;
const struct scev_info_str *elt2 = (const struct scev_info_str *) e2;
return elt1->var == elt2->var;
}
static void
del_scev_info (void *e)
{
free (e);
}
static tree *
find_var_scev_info (tree var)
{
struct scev_info_str *res;
struct scev_info_str tmp;
PTR *slot;
tmp.var = var;
slot = htab_find_slot (scalar_evolution_info, &tmp, INSERT);
if (!*slot)
*slot = new_scev_info_str (var);
res = (struct scev_info_str *) *slot;
return &res->chrec;
}
bool
chrec_contains_symbols_defined_in_loop (tree chrec, unsigned loop_nb)
{
if (chrec == NULL_TREE)
return false;
if (TREE_INVARIANT (chrec))
return false;
if (TREE_CODE (chrec) == VAR_DECL
|| TREE_CODE (chrec) == PARM_DECL
|| TREE_CODE (chrec) == FUNCTION_DECL
|| TREE_CODE (chrec) == LABEL_DECL
|| TREE_CODE (chrec) == RESULT_DECL
|| TREE_CODE (chrec) == FIELD_DECL)
return true;
if (TREE_CODE (chrec) == SSA_NAME)
{
tree def = SSA_NAME_DEF_STMT (chrec);
struct loop *def_loop = loop_containing_stmt (def);
struct loop *loop = current_loops->parray[loop_nb];
if (def_loop == NULL)
return false;
if (loop == def_loop || flow_loop_nested_p (loop, def_loop))
return true;
return false;
}
switch (TREE_CODE_LENGTH (TREE_CODE (chrec)))
{
case 3:
if (chrec_contains_symbols_defined_in_loop (TREE_OPERAND (chrec, 2),
loop_nb))
return true;
case 2:
if (chrec_contains_symbols_defined_in_loop (TREE_OPERAND (chrec, 1),
loop_nb))
return true;
case 1:
if (chrec_contains_symbols_defined_in_loop (TREE_OPERAND (chrec, 0),
loop_nb))
return true;
default:
return false;
}
}
static bool
loop_phi_node_p (tree phi)
{
return loop_containing_stmt (phi)->header == bb_for_stmt (phi);
}
static tree
compute_overall_effect_of_inner_loop (struct loop *loop, tree evolution_fn)
{
bool val = false;
if (evolution_fn == chrec_dont_know)
return chrec_dont_know;
else if (TREE_CODE (evolution_fn) == POLYNOMIAL_CHREC)
{
if (CHREC_VARIABLE (evolution_fn) >= (unsigned) loop->num)
{
struct loop *inner_loop =
current_loops->parray[CHREC_VARIABLE (evolution_fn)];
tree nb_iter = number_of_iterations_in_loop (inner_loop);
if (nb_iter == chrec_dont_know)
return chrec_dont_know;
else
{
tree res;
tree type = chrec_type (nb_iter);
nb_iter = chrec_fold_minus (type, nb_iter,
build_int_cst (type, 1));
res = chrec_apply (inner_loop->num, evolution_fn, nb_iter);
return compute_overall_effect_of_inner_loop (loop, res);
}
}
else
return evolution_fn;
}
else if (no_evolution_in_loop_p (evolution_fn, loop->num, &val) && val)
return evolution_fn;
else
return chrec_dont_know;
}
bool
chrec_is_positive (tree chrec, bool *value)
{
bool value0, value1, value2;
tree type, end_value, nb_iter;
switch (TREE_CODE (chrec))
{
case POLYNOMIAL_CHREC:
if (!chrec_is_positive (CHREC_LEFT (chrec), &value0)
|| !chrec_is_positive (CHREC_RIGHT (chrec), &value1))
return false;
if (value0 == value1)
{
*value = value0;
return true;
}
if (!evolution_function_is_affine_p (chrec))
return false;
nb_iter = number_of_iterations_in_loop
(current_loops->parray[CHREC_VARIABLE (chrec)]);
if (chrec_contains_undetermined (nb_iter))
return false;
type = chrec_type (nb_iter);
nb_iter = chrec_fold_minus (type, nb_iter, build_int_cst (type, 1));
#if 0
if (after_exit)
nb_iter = chrec_fold_minus (type, nb_iter, build_int_cst (type, 1));
#endif
end_value = chrec_apply (CHREC_VARIABLE (chrec), chrec, nb_iter);
if (!chrec_is_positive (end_value, &value2))
return false;
*value = value0;
return value0 == value1;
case INTEGER_CST:
*value = (tree_int_cst_sgn (chrec) == 1);
return true;
default:
return false;
}
}
static void
set_scalar_evolution (tree scalar, tree chrec)
{
tree *scalar_info;
if (TREE_CODE (scalar) != SSA_NAME)
return;
scalar_info = find_var_scev_info (scalar);
if (dump_file)
{
if (dump_flags & TDF_DETAILS)
{
fprintf (dump_file, "(set_scalar_evolution \n");
fprintf (dump_file, " (scalar = ");
print_generic_expr (dump_file, scalar, 0);
fprintf (dump_file, ")\n (scalar_evolution = ");
print_generic_expr (dump_file, chrec, 0);
fprintf (dump_file, "))\n");
}
if (dump_flags & TDF_STATS)
nb_set_scev++;
}
*scalar_info = chrec;
}
static tree
get_scalar_evolution (tree scalar)
{
tree res;
if (dump_file)
{
if (dump_flags & TDF_DETAILS)
{
fprintf (dump_file, "(get_scalar_evolution \n");
fprintf (dump_file, " (scalar = ");
print_generic_expr (dump_file, scalar, 0);
fprintf (dump_file, ")\n");
}
if (dump_flags & TDF_STATS)
nb_get_scev++;
}
switch (TREE_CODE (scalar))
{
case SSA_NAME:
res = *find_var_scev_info (scalar);
break;
case REAL_CST:
case INTEGER_CST:
res = scalar;
break;
default:
res = chrec_not_analyzed_yet;
break;
}
if (dump_file && (dump_flags & TDF_DETAILS))
{
fprintf (dump_file, " (scalar_evolution = ");
print_generic_expr (dump_file, res, 0);
fprintf (dump_file, "))\n");
}
return res;
}
static tree
add_to_evolution_1 (unsigned loop_nb, tree chrec_before, tree to_add,
tree at_stmt)
{
tree type, left, right;
switch (TREE_CODE (chrec_before))
{
case POLYNOMIAL_CHREC:
if (CHREC_VARIABLE (chrec_before) <= loop_nb)
{
unsigned var;
type = chrec_type (chrec_before);
if (CHREC_VARIABLE (chrec_before) < loop_nb)
{
var = loop_nb;
left = chrec_before;
right = SCALAR_FLOAT_TYPE_P (type)
? build_real (type, dconst0)
: build_int_cst (type, 0);
}
else
{
var = CHREC_VARIABLE (chrec_before);
left = CHREC_LEFT (chrec_before);
right = CHREC_RIGHT (chrec_before);
}
to_add = chrec_convert (type, to_add, at_stmt);
right = chrec_convert (type, right, at_stmt);
right = chrec_fold_plus (type, right, to_add);
return build_polynomial_chrec (var, left, right);
}
else
{
left = add_to_evolution_1 (loop_nb, CHREC_LEFT (chrec_before),
to_add, at_stmt);
right = CHREC_RIGHT (chrec_before);
right = chrec_convert (chrec_type (left), right, at_stmt);
return build_polynomial_chrec (CHREC_VARIABLE (chrec_before),
left, right);
}
default:
if (chrec_before == chrec_dont_know)
return chrec_dont_know;
left = chrec_before;
right = chrec_convert (chrec_type (left), to_add, at_stmt);
return build_polynomial_chrec (loop_nb, left, right);
}
}
static tree
add_to_evolution (unsigned loop_nb, tree chrec_before, enum tree_code code,
tree to_add, tree at_stmt)
{
tree type = chrec_type (to_add);
tree res = NULL_TREE;
if (to_add == NULL_TREE)
return chrec_before;
if (TREE_CODE (to_add) == POLYNOMIAL_CHREC)
return chrec_dont_know;
if (dump_file && (dump_flags & TDF_DETAILS))
{
fprintf (dump_file, "(add_to_evolution \n");
fprintf (dump_file, " (loop_nb = %d)\n", loop_nb);
fprintf (dump_file, " (chrec_before = ");
print_generic_expr (dump_file, chrec_before, 0);
fprintf (dump_file, ")\n (to_add = ");
print_generic_expr (dump_file, to_add, 0);
fprintf (dump_file, ")\n");
}
if (code == MINUS_EXPR)
to_add = chrec_fold_multiply (type, to_add, SCALAR_FLOAT_TYPE_P (type)
? build_real (type, dconstm1)
: build_int_cst_type (type, -1));
res = add_to_evolution_1 (loop_nb, chrec_before, to_add, at_stmt);
if (dump_file && (dump_flags & TDF_DETAILS))
{
fprintf (dump_file, " (res = ");
print_generic_expr (dump_file, res, 0);
fprintf (dump_file, "))\n");
}
return res;
}
static inline tree
set_nb_iterations_in_loop (struct loop *loop,
tree res)
{
tree type = chrec_type (res);
res = chrec_fold_plus (type, res, build_int_cst (type, 1));
if (TREE_CODE (res) == INTEGER_CST
&& (TREE_INT_CST_LOW (res) == 0
|| TREE_OVERFLOW (res)))
res = chrec_dont_know;
if (dump_file && (dump_flags & TDF_DETAILS))
{
fprintf (dump_file, " (set_nb_iterations_in_loop = ");
print_generic_expr (dump_file, res, 0);
fprintf (dump_file, "))\n");
}
loop->nb_iterations = res;
return res;
}
static bool
analyzable_condition (tree expr)
{
tree condition;
if (TREE_CODE (expr) != COND_EXPR)
return false;
condition = TREE_OPERAND (expr, 0);
switch (TREE_CODE (condition))
{
case SSA_NAME:
return true;
case LT_EXPR:
case LE_EXPR:
case GT_EXPR:
case GE_EXPR:
case EQ_EXPR:
case NE_EXPR:
return true;
default:
return false;
}
return false;
}
tree
get_loop_exit_condition (struct loop *loop)
{
tree res = NULL_TREE;
edge exit_edge = loop->single_exit;
if (dump_file && (dump_flags & TDF_DETAILS))
fprintf (dump_file, "(get_loop_exit_condition \n ");
if (exit_edge)
{
tree expr;
expr = last_stmt (exit_edge->src);
if (analyzable_condition (expr))
res = expr;
}
if (dump_file && (dump_flags & TDF_DETAILS))
{
print_generic_expr (dump_file, res, 0);
fprintf (dump_file, ")\n");
}
return res;
}
static void
get_exit_conditions_rec (struct loop *loop,
VEC(tree,heap) **exit_conditions)
{
if (!loop)
return;
get_exit_conditions_rec (loop->inner, exit_conditions);
get_exit_conditions_rec (loop->next, exit_conditions);
if (loop->single_exit)
{
tree loop_condition = get_loop_exit_condition (loop);
if (loop_condition)
VEC_safe_push (tree, heap, *exit_conditions, loop_condition);
}
}
static void
select_loops_exit_conditions (struct loops *loops,
VEC(tree,heap) **exit_conditions)
{
struct loop *function_body = loops->parray[0];
get_exit_conditions_rec (function_body->inner, exit_conditions);
}
typedef enum t_bool {
t_false,
t_true,
t_dont_know
} t_bool;
static t_bool follow_ssa_edge (struct loop *loop, tree, tree, tree *, int);
static t_bool
follow_ssa_edge_in_rhs (struct loop *loop, tree at_stmt, tree rhs,
tree halting_phi, tree *evolution_of_loop, int limit)
{
t_bool res = t_false;
tree rhs0, rhs1;
tree type_rhs = TREE_TYPE (rhs);
tree evol;
switch (TREE_CODE (rhs))
{
case NOP_EXPR:
res = follow_ssa_edge_in_rhs (loop, at_stmt, TREE_OPERAND (rhs, 0),
halting_phi, evolution_of_loop, limit);
*evolution_of_loop = chrec_convert (TREE_TYPE (rhs),
*evolution_of_loop, at_stmt);
break;
case INTEGER_CST:
res = t_false;
break;
case SSA_NAME:
res = follow_ssa_edge
(loop, SSA_NAME_DEF_STMT (rhs), halting_phi, evolution_of_loop, limit);
break;
case PLUS_EXPR:
rhs0 = TREE_OPERAND (rhs, 0);
rhs1 = TREE_OPERAND (rhs, 1);
STRIP_TYPE_NOPS (rhs0);
STRIP_TYPE_NOPS (rhs1);
if (TREE_CODE (rhs0) == SSA_NAME)
{
if (TREE_CODE (rhs1) == SSA_NAME)
{
evol = *evolution_of_loop;
res = follow_ssa_edge
(loop, SSA_NAME_DEF_STMT (rhs0), halting_phi,
&evol, limit);
if (res == t_true)
*evolution_of_loop = add_to_evolution
(loop->num,
chrec_convert (type_rhs, evol, at_stmt),
PLUS_EXPR, rhs1, at_stmt);
else if (res == t_false)
{
res = follow_ssa_edge
(loop, SSA_NAME_DEF_STMT (rhs1), halting_phi,
evolution_of_loop, limit);
if (res == t_true)
*evolution_of_loop = add_to_evolution
(loop->num,
chrec_convert (type_rhs, *evolution_of_loop, at_stmt),
PLUS_EXPR, rhs0, at_stmt);
else if (res == t_dont_know)
*evolution_of_loop = chrec_dont_know;
}
else if (res == t_dont_know)
*evolution_of_loop = chrec_dont_know;
}
else
{
res = follow_ssa_edge
(loop, SSA_NAME_DEF_STMT (rhs0), halting_phi,
evolution_of_loop, limit);
if (res == t_true)
*evolution_of_loop = add_to_evolution
(loop->num, chrec_convert (type_rhs, *evolution_of_loop,
at_stmt),
PLUS_EXPR, rhs1, at_stmt);
else if (res == t_dont_know)
*evolution_of_loop = chrec_dont_know;
}
}
else if (TREE_CODE (rhs1) == SSA_NAME)
{
res = follow_ssa_edge
(loop, SSA_NAME_DEF_STMT (rhs1), halting_phi,
evolution_of_loop, limit);
if (res == t_true)
*evolution_of_loop = add_to_evolution
(loop->num, chrec_convert (type_rhs, *evolution_of_loop,
at_stmt),
PLUS_EXPR, rhs0, at_stmt);
else if (res == t_dont_know)
*evolution_of_loop = chrec_dont_know;
}
else
res = t_false;
break;
case MINUS_EXPR:
rhs0 = TREE_OPERAND (rhs, 0);
rhs1 = TREE_OPERAND (rhs, 1);
STRIP_TYPE_NOPS (rhs0);
STRIP_TYPE_NOPS (rhs1);
if (TREE_CODE (rhs0) == SSA_NAME)
{
res = follow_ssa_edge (loop, SSA_NAME_DEF_STMT (rhs0), halting_phi,
evolution_of_loop, limit);
if (res == t_true)
*evolution_of_loop = add_to_evolution
(loop->num, chrec_convert (type_rhs, *evolution_of_loop, at_stmt),
MINUS_EXPR, rhs1, at_stmt);
else if (res == t_dont_know)
*evolution_of_loop = chrec_dont_know;
}
else
res = t_false;
break;
case ASSERT_EXPR:
{
tree op0 = ASSERT_EXPR_VAR (rhs);
if (TREE_CODE (op0) == SSA_NAME)
res = follow_ssa_edge (loop, SSA_NAME_DEF_STMT (op0),
halting_phi, evolution_of_loop, limit);
else
res = t_false;
break;
}
default:
res = t_false;
break;
}
return res;
}
static bool
backedge_phi_arg_p (tree phi, int i)
{
edge e = PHI_ARG_EDGE (phi, i);
if (e->flags & EDGE_IRREDUCIBLE_LOOP)
return true;
return false;
}
static inline t_bool
follow_ssa_edge_in_condition_phi_branch (int i,
struct loop *loop,
tree condition_phi,
tree halting_phi,
tree *evolution_of_branch,
tree init_cond, int limit)
{
tree branch = PHI_ARG_DEF (condition_phi, i);
*evolution_of_branch = chrec_dont_know;
if (backedge_phi_arg_p (condition_phi, i))
return t_false;
if (TREE_CODE (branch) == SSA_NAME)
{
*evolution_of_branch = init_cond;
return follow_ssa_edge (loop, SSA_NAME_DEF_STMT (branch), halting_phi,
evolution_of_branch, limit);
}
return t_false;
}
static t_bool
follow_ssa_edge_in_condition_phi (struct loop *loop,
tree condition_phi,
tree halting_phi,
tree *evolution_of_loop, int limit)
{
int i;
tree init = *evolution_of_loop;
tree evolution_of_branch;
t_bool res = follow_ssa_edge_in_condition_phi_branch (0, loop, condition_phi,
halting_phi,
&evolution_of_branch,
init, limit);
if (res == t_false || res == t_dont_know)
return res;
*evolution_of_loop = evolution_of_branch;
for (i = 1; i < PHI_NUM_ARGS (condition_phi); i++)
{
if (*evolution_of_loop == chrec_dont_know)
return t_true;
res = follow_ssa_edge_in_condition_phi_branch (i, loop, condition_phi,
halting_phi,
&evolution_of_branch,
init, limit);
if (res == t_false || res == t_dont_know)
return res;
*evolution_of_loop = chrec_merge (*evolution_of_loop,
evolution_of_branch);
}
return t_true;
}
static t_bool
follow_ssa_edge_inner_loop_phi (struct loop *outer_loop,
tree loop_phi_node,
tree halting_phi,
tree *evolution_of_loop, int limit)
{
struct loop *loop = loop_containing_stmt (loop_phi_node);
tree ev = analyze_scalar_evolution (loop, PHI_RESULT (loop_phi_node));
if (ev == PHI_RESULT (loop_phi_node))
{
t_bool res = t_false;
int i;
for (i = 0; i < PHI_NUM_ARGS (loop_phi_node); i++)
{
tree arg = PHI_ARG_DEF (loop_phi_node, i);
basic_block bb;
bb = PHI_ARG_EDGE (loop_phi_node, i)->src;
if (!flow_bb_inside_loop_p (loop, bb))
res = follow_ssa_edge_in_rhs (outer_loop, loop_phi_node,
arg, halting_phi,
evolution_of_loop, limit);
if (res == t_true)
break;
}
if (res == t_true)
*evolution_of_loop = chrec_dont_know;
return res;
}
ev = compute_overall_effect_of_inner_loop (loop, ev);
return follow_ssa_edge_in_rhs (outer_loop, loop_phi_node, ev, halting_phi,
evolution_of_loop, limit);
}
static t_bool
follow_ssa_edge (struct loop *loop, tree def, tree halting_phi,
tree *evolution_of_loop, int limit)
{
struct loop *def_loop;
if (TREE_CODE (def) == NOP_EXPR)
return t_false;
if (limit++ > PARAM_VALUE (PARAM_SCEV_MAX_EXPR_SIZE))
return t_dont_know;
def_loop = loop_containing_stmt (def);
switch (TREE_CODE (def))
{
case PHI_NODE:
if (!loop_phi_node_p (def))
return follow_ssa_edge_in_condition_phi
(loop, def, halting_phi, evolution_of_loop, limit);
if (def == halting_phi)
return t_true;
if (def_loop == loop)
return t_false;
if (flow_loop_nested_p (loop, def_loop))
return follow_ssa_edge_inner_loop_phi
(loop, def, halting_phi, evolution_of_loop, limit);
return t_false;
case MODIFY_EXPR:
return follow_ssa_edge_in_rhs (loop, def,
TREE_OPERAND (def, 1),
halting_phi,
evolution_of_loop, limit);
default:
return t_false;
}
}
static tree
analyze_evolution_in_loop (tree loop_phi_node,
tree init_cond)
{
int i;
tree evolution_function = chrec_not_analyzed_yet;
struct loop *loop = loop_containing_stmt (loop_phi_node);
basic_block bb;
if (dump_file && (dump_flags & TDF_DETAILS))
{
fprintf (dump_file, "(analyze_evolution_in_loop \n");
fprintf (dump_file, " (loop_phi_node = ");
print_generic_expr (dump_file, loop_phi_node, 0);
fprintf (dump_file, ")\n");
}
for (i = 0; i < PHI_NUM_ARGS (loop_phi_node); i++)
{
tree arg = PHI_ARG_DEF (loop_phi_node, i);
tree ssa_chain, ev_fn;
t_bool res;
bb = PHI_ARG_EDGE (loop_phi_node, i)->src;
if (!flow_bb_inside_loop_p (loop, bb))
continue;
if (TREE_CODE (arg) == SSA_NAME)
{
ssa_chain = SSA_NAME_DEF_STMT (arg);
ev_fn = init_cond;
res = follow_ssa_edge (loop, ssa_chain, loop_phi_node, &ev_fn, 0);
}
else
res = t_false;
if (res != t_true)
ev_fn = chrec_dont_know;
evolution_function = chrec_merge (evolution_function, ev_fn);
}
if (dump_file && (dump_flags & TDF_DETAILS))
{
fprintf (dump_file, " (evolution_function = ");
print_generic_expr (dump_file, evolution_function, 0);
fprintf (dump_file, "))\n");
}
return evolution_function;
}
static tree
analyze_initial_condition (tree loop_phi_node)
{
int i;
tree init_cond = chrec_not_analyzed_yet;
struct loop *loop = bb_for_stmt (loop_phi_node)->loop_father;
if (dump_file && (dump_flags & TDF_DETAILS))
{
fprintf (dump_file, "(analyze_initial_condition \n");
fprintf (dump_file, " (loop_phi_node = \n");
print_generic_expr (dump_file, loop_phi_node, 0);
fprintf (dump_file, ")\n");
}
for (i = 0; i < PHI_NUM_ARGS (loop_phi_node); i++)
{
tree branch = PHI_ARG_DEF (loop_phi_node, i);
basic_block bb = PHI_ARG_EDGE (loop_phi_node, i)->src;
if (flow_bb_inside_loop_p (loop, bb))
continue;
if (init_cond == chrec_not_analyzed_yet)
{
init_cond = branch;
continue;
}
if (TREE_CODE (branch) == SSA_NAME)
{
init_cond = chrec_dont_know;
break;
}
init_cond = chrec_merge (init_cond, branch);
}
if (init_cond == chrec_not_analyzed_yet)
init_cond = chrec_dont_know;
if (dump_file && (dump_flags & TDF_DETAILS))
{
fprintf (dump_file, " (init_cond = ");
print_generic_expr (dump_file, init_cond, 0);
fprintf (dump_file, "))\n");
}
return init_cond;
}
static tree
interpret_loop_phi (struct loop *loop, tree loop_phi_node)
{
tree res;
struct loop *phi_loop = loop_containing_stmt (loop_phi_node);
tree init_cond;
if (phi_loop != loop)
{
struct loop *subloop;
tree evolution_fn = analyze_scalar_evolution
(phi_loop, PHI_RESULT (loop_phi_node));
subloop = superloop_at_depth (phi_loop, loop->depth + 1);
res = compute_overall_effect_of_inner_loop (subloop, evolution_fn);
return res;
}
init_cond = analyze_initial_condition (loop_phi_node);
res = analyze_evolution_in_loop (loop_phi_node, init_cond);
return res;
}
static tree
interpret_condition_phi (struct loop *loop, tree condition_phi)
{
int i;
tree res = chrec_not_analyzed_yet;
for (i = 0; i < PHI_NUM_ARGS (condition_phi); i++)
{
tree branch_chrec;
if (backedge_phi_arg_p (condition_phi, i))
{
res = chrec_dont_know;
break;
}
branch_chrec = analyze_scalar_evolution
(loop, PHI_ARG_DEF (condition_phi, i));
res = chrec_merge (res, branch_chrec);
}
return res;
}
static tree
interpret_rhs_modify_expr (struct loop *loop, tree at_stmt,
tree opnd1, tree type)
{
tree res, opnd10, opnd11, chrec10, chrec11;
if (is_gimple_min_invariant (opnd1))
return chrec_convert (type, opnd1, at_stmt);
switch (TREE_CODE (opnd1))
{
case PLUS_EXPR:
opnd10 = TREE_OPERAND (opnd1, 0);
opnd11 = TREE_OPERAND (opnd1, 1);
chrec10 = analyze_scalar_evolution (loop, opnd10);
chrec11 = analyze_scalar_evolution (loop, opnd11);
chrec10 = chrec_convert (type, chrec10, at_stmt);
chrec11 = chrec_convert (type, chrec11, at_stmt);
res = chrec_fold_plus (type, chrec10, chrec11);
break;
case MINUS_EXPR:
opnd10 = TREE_OPERAND (opnd1, 0);
opnd11 = TREE_OPERAND (opnd1, 1);
chrec10 = analyze_scalar_evolution (loop, opnd10);
chrec11 = analyze_scalar_evolution (loop, opnd11);
chrec10 = chrec_convert (type, chrec10, at_stmt);
chrec11 = chrec_convert (type, chrec11, at_stmt);
res = chrec_fold_minus (type, chrec10, chrec11);
break;
case NEGATE_EXPR:
opnd10 = TREE_OPERAND (opnd1, 0);
chrec10 = analyze_scalar_evolution (loop, opnd10);
chrec10 = chrec_convert (type, chrec10, at_stmt);
res = chrec_fold_multiply (type, chrec10,
fold_convert (type, integer_minus_one_node));
break;
case MULT_EXPR:
opnd10 = TREE_OPERAND (opnd1, 0);
opnd11 = TREE_OPERAND (opnd1, 1);
chrec10 = analyze_scalar_evolution (loop, opnd10);
chrec11 = analyze_scalar_evolution (loop, opnd11);
chrec10 = chrec_convert (type, chrec10, at_stmt);
chrec11 = chrec_convert (type, chrec11, at_stmt);
res = chrec_fold_multiply (type, chrec10, chrec11);
break;
case SSA_NAME:
res = chrec_convert (type, analyze_scalar_evolution (loop, opnd1),
at_stmt);
break;
case ASSERT_EXPR:
opnd10 = ASSERT_EXPR_VAR (opnd1);
res = chrec_convert (type, analyze_scalar_evolution (loop, opnd10),
at_stmt);
break;
case NOP_EXPR:
case CONVERT_EXPR:
opnd10 = TREE_OPERAND (opnd1, 0);
chrec10 = analyze_scalar_evolution (loop, opnd10);
res = chrec_convert (type, chrec10, at_stmt);
break;
default:
res = chrec_dont_know;
break;
}
return res;
}
static tree
compute_scalar_evolution_in_loop (struct loop *wrto_loop,
struct loop *def_loop,
tree ev)
{
tree res;
if (def_loop == wrto_loop)
return ev;
def_loop = superloop_at_depth (def_loop, wrto_loop->depth + 1);
res = compute_overall_effect_of_inner_loop (def_loop, ev);
return analyze_scalar_evolution_1 (wrto_loop, res, chrec_not_analyzed_yet);
}
static tree
fold_used_pointer_cast (tree expr)
{
tree op;
tree type, inner_type;
if (TREE_CODE (expr) != NOP_EXPR && TREE_CODE (expr) != CONVERT_EXPR)
return expr;
op = TREE_OPERAND (expr, 0);
if (TREE_CODE (op) != POLYNOMIAL_CHREC)
return expr;
type = TREE_TYPE (expr);
inner_type = TREE_TYPE (op);
if (!INTEGRAL_TYPE_P (inner_type)
|| TYPE_PRECISION (inner_type) != TYPE_PRECISION (type))
return expr;
return build_polynomial_chrec (CHREC_VARIABLE (op),
chrec_convert (type, CHREC_LEFT (op), NULL_TREE),
chrec_convert (type, CHREC_RIGHT (op), NULL_TREE));
}
static bool
pointer_offset_p (tree expr)
{
if (TREE_CODE (expr) == INTEGER_CST)
return true;
if ((TREE_CODE (expr) == NOP_EXPR || TREE_CODE (expr) == CONVERT_EXPR)
&& INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (expr, 0))))
return true;
return false;
}
static tree
fold_used_pointer (tree expr, tree at_stmt)
{
tree op0, op1, new0, new1;
enum tree_code code = TREE_CODE (expr);
if (code == PLUS_EXPR
|| code == MINUS_EXPR)
{
op0 = TREE_OPERAND (expr, 0);
op1 = TREE_OPERAND (expr, 1);
if (pointer_offset_p (op1))
{
new0 = fold_used_pointer (op0, at_stmt);
new1 = fold_used_pointer_cast (op1);
}
else if (code == PLUS_EXPR && pointer_offset_p (op0))
{
new0 = fold_used_pointer_cast (op0);
new1 = fold_used_pointer (op1, at_stmt);
}
else
return expr;
if (new0 == op0 && new1 == op1)
return expr;
new0 = chrec_convert (TREE_TYPE (expr), new0, at_stmt);
new1 = chrec_convert (TREE_TYPE (expr), new1, at_stmt);
if (code == PLUS_EXPR)
expr = chrec_fold_plus (TREE_TYPE (expr), new0, new1);
else
expr = chrec_fold_minus (TREE_TYPE (expr), new0, new1);
return expr;
}
else
return fold_used_pointer_cast (expr);
}
static bool
pointer_used_p (tree ptr)
{
use_operand_p use_p;
imm_use_iterator imm_iter;
tree stmt, rhs;
struct ptr_info_def *pi = get_ptr_info (ptr);
var_ann_t v_ann = var_ann (SSA_NAME_VAR (ptr));
if ((pi != NULL && pi->name_mem_tag != NULL)
|| v_ann->symbol_mem_tag)
return true;
FOR_EACH_IMM_USE_FAST (use_p, imm_iter, ptr)
{
stmt = USE_STMT (use_p);
if (TREE_CODE (stmt) == COND_EXPR)
return true;
if (TREE_CODE (stmt) != MODIFY_EXPR)
continue;
rhs = TREE_OPERAND (stmt, 1);
if (!COMPARISON_CLASS_P (rhs))
continue;
if (TREE_OPERAND (stmt, 0) == ptr
|| TREE_OPERAND (stmt, 1) == ptr)
return true;
}
return false;
}
static tree
analyze_scalar_evolution_1 (struct loop *loop, tree var, tree res)
{
tree def, type = TREE_TYPE (var);
basic_block bb;
struct loop *def_loop;
if (loop == NULL || TREE_CODE (type) == VECTOR_TYPE)
return chrec_dont_know;
if (TREE_CODE (var) != SSA_NAME)
return interpret_rhs_modify_expr (loop, NULL_TREE, var, type);
def = SSA_NAME_DEF_STMT (var);
bb = bb_for_stmt (def);
def_loop = bb ? bb->loop_father : NULL;
if (bb == NULL
|| !flow_bb_inside_loop_p (loop, bb))
{
res = var;
goto set_and_end;
}
if (res != chrec_not_analyzed_yet)
{
if (loop != bb->loop_father)
res = compute_scalar_evolution_in_loop
(find_common_loop (loop, bb->loop_father), bb->loop_father, res);
goto set_and_end;
}
if (loop != def_loop)
{
res = analyze_scalar_evolution_1 (def_loop, var, chrec_not_analyzed_yet);
res = compute_scalar_evolution_in_loop (loop, def_loop, res);
goto set_and_end;
}
switch (TREE_CODE (def))
{
case MODIFY_EXPR:
res = interpret_rhs_modify_expr (loop, def, TREE_OPERAND (def, 1), type);
if (POINTER_TYPE_P (type)
&& !automatically_generated_chrec_p (res)
&& pointer_used_p (var))
res = fold_used_pointer (res, def);
break;
case PHI_NODE:
if (loop_phi_node_p (def))
res = interpret_loop_phi (loop, def);
else
res = interpret_condition_phi (loop, def);
break;
default:
res = chrec_dont_know;
break;
}
set_and_end:
if (res == chrec_dont_know)
res = var;
if (loop == def_loop)
set_scalar_evolution (var, res);
return res;
}
tree
analyze_scalar_evolution (struct loop *loop, tree var)
{
tree res;
if (dump_file && (dump_flags & TDF_DETAILS))
{
fprintf (dump_file, "(analyze_scalar_evolution \n");
fprintf (dump_file, " (loop_nb = %d)\n", loop->num);
fprintf (dump_file, " (scalar = ");
print_generic_expr (dump_file, var, 0);
fprintf (dump_file, ")\n");
}
res = analyze_scalar_evolution_1 (loop, var, get_scalar_evolution (var));
if (TREE_CODE (var) == SSA_NAME && res == chrec_dont_know)
res = var;
if (dump_file && (dump_flags & TDF_DETAILS))
fprintf (dump_file, ")\n");
return res;
}
static tree
analyze_scalar_evolution_in_loop (struct loop *wrto_loop, struct loop *use_loop,
tree version, bool *folded_casts)
{
bool val = false;
tree ev = version, tmp;
if (folded_casts)
*folded_casts = false;
while (1)
{
tmp = analyze_scalar_evolution (use_loop, ev);
ev = resolve_mixers (use_loop, tmp);
if (folded_casts && tmp != ev)
*folded_casts = true;
if (use_loop == wrto_loop)
return ev;
if (!no_evolution_in_loop_p (ev, use_loop->num, &val)
|| !val)
return chrec_dont_know;
use_loop = use_loop->outer;
}
}
static tree
get_instantiated_value (htab_t cache, tree version)
{
struct scev_info_str *info, pattern;
pattern.var = version;
info = (struct scev_info_str *) htab_find (cache, &pattern);
if (info)
return info->chrec;
else
return NULL_TREE;
}
static void
set_instantiated_value (htab_t cache, tree version, tree val)
{
struct scev_info_str *info, pattern;
PTR *slot;
pattern.var = version;
slot = htab_find_slot (cache, &pattern, INSERT);
if (!*slot)
*slot = new_scev_info_str (version);
info = (struct scev_info_str *) *slot;
info->chrec = val;
}
static tree
loop_closed_phi_def (tree var)
{
struct loop *loop;
edge exit;
tree phi;
if (var == NULL_TREE
|| TREE_CODE (var) != SSA_NAME)
return NULL_TREE;
loop = loop_containing_stmt (SSA_NAME_DEF_STMT (var));
exit = loop->single_exit;
if (!exit)
return NULL_TREE;
for (phi = phi_nodes (exit->dest); phi; phi = PHI_CHAIN (phi))
if (PHI_ARG_DEF_FROM_EDGE (phi, exit) == var)
return PHI_RESULT (phi);
return NULL_TREE;
}
enum
{
INSERT_SUPERLOOP_CHRECS = 1,
FOLD_CONVERSIONS = 2
};
static tree
instantiate_parameters_1 (struct loop *loop, tree chrec, int flags, htab_t cache,
int size_expr)
{
tree res, op0, op1, op2;
basic_block def_bb;
struct loop *def_loop;
tree type = chrec_type (chrec);
if (size_expr++ > PARAM_VALUE (PARAM_SCEV_MAX_EXPR_SIZE))
return chrec_dont_know;
if (automatically_generated_chrec_p (chrec)
|| is_gimple_min_invariant (chrec))
return chrec;
switch (TREE_CODE (chrec))
{
case SSA_NAME:
def_bb = bb_for_stmt (SSA_NAME_DEF_STMT (chrec));
if (!def_bb
|| (!(flags & INSERT_SUPERLOOP_CHRECS)
&& !flow_bb_inside_loop_p (loop, def_bb)))
return chrec;
res = get_instantiated_value (cache, chrec);
if (res)
return res;
res = !flow_bb_inside_loop_p (loop, def_bb) ? chrec : chrec_dont_know;
set_instantiated_value (cache, chrec, res);
if (bitmap_bit_p (already_instantiated, SSA_NAME_VERSION (chrec)))
return res;
def_loop = find_common_loop (loop, def_bb->loop_father);
bitmap_set_bit (already_instantiated, SSA_NAME_VERSION (chrec));
res = analyze_scalar_evolution (def_loop, chrec);
if (TREE_CODE (res) == SSA_NAME
&& (loop_containing_stmt (SSA_NAME_DEF_STMT (res)) == NULL
|| (loop_containing_stmt (SSA_NAME_DEF_STMT (res))->depth
> def_loop->depth)))
{
if (res == chrec)
res = loop_closed_phi_def (chrec);
else
res = chrec;
if (res == NULL_TREE)
res = chrec_dont_know;
}
else if (res != chrec_dont_know)
res = instantiate_parameters_1 (loop, res, flags, cache, size_expr);
bitmap_clear_bit (already_instantiated, SSA_NAME_VERSION (chrec));
set_instantiated_value (cache, chrec, res);
return res;
case POLYNOMIAL_CHREC:
op0 = instantiate_parameters_1 (loop, CHREC_LEFT (chrec),
flags, cache, size_expr);
if (op0 == chrec_dont_know)
return chrec_dont_know;
op1 = instantiate_parameters_1 (loop, CHREC_RIGHT (chrec),
flags, cache, size_expr);
if (op1 == chrec_dont_know)
return chrec_dont_know;
if (CHREC_LEFT (chrec) != op0
|| CHREC_RIGHT (chrec) != op1)
{
op1 = chrec_convert (chrec_type (op0), op1, NULL_TREE);
chrec = build_polynomial_chrec (CHREC_VARIABLE (chrec), op0, op1);
}
return chrec;
case PLUS_EXPR:
op0 = instantiate_parameters_1 (loop, TREE_OPERAND (chrec, 0),
flags, cache, size_expr);
if (op0 == chrec_dont_know)
return chrec_dont_know;
op1 = instantiate_parameters_1 (loop, TREE_OPERAND (chrec, 1),
flags, cache, size_expr);
if (op1 == chrec_dont_know)
return chrec_dont_know;
if (TREE_OPERAND (chrec, 0) != op0
|| TREE_OPERAND (chrec, 1) != op1)
{
op0 = chrec_convert (type, op0, NULL_TREE);
op1 = chrec_convert (type, op1, NULL_TREE);
chrec = chrec_fold_plus (type, op0, op1);
}
return chrec;
case MINUS_EXPR:
op0 = instantiate_parameters_1 (loop, TREE_OPERAND (chrec, 0),
flags, cache, size_expr);
if (op0 == chrec_dont_know)
return chrec_dont_know;
op1 = instantiate_parameters_1 (loop, TREE_OPERAND (chrec, 1),
flags, cache, size_expr);
if (op1 == chrec_dont_know)
return chrec_dont_know;
if (TREE_OPERAND (chrec, 0) != op0
|| TREE_OPERAND (chrec, 1) != op1)
{
op0 = chrec_convert (type, op0, NULL_TREE);
op1 = chrec_convert (type, op1, NULL_TREE);
chrec = chrec_fold_minus (type, op0, op1);
}
return chrec;
case MULT_EXPR:
op0 = instantiate_parameters_1 (loop, TREE_OPERAND (chrec, 0),
flags, cache, size_expr);
if (op0 == chrec_dont_know)
return chrec_dont_know;
op1 = instantiate_parameters_1 (loop, TREE_OPERAND (chrec, 1),
flags, cache, size_expr);
if (op1 == chrec_dont_know)
return chrec_dont_know;
if (TREE_OPERAND (chrec, 0) != op0
|| TREE_OPERAND (chrec, 1) != op1)
{
op0 = chrec_convert (type, op0, NULL_TREE);
op1 = chrec_convert (type, op1, NULL_TREE);
chrec = chrec_fold_multiply (type, op0, op1);
}
return chrec;
case NOP_EXPR:
case CONVERT_EXPR:
case NON_LVALUE_EXPR:
op0 = instantiate_parameters_1 (loop, TREE_OPERAND (chrec, 0),
flags, cache, size_expr);
if (op0 == chrec_dont_know)
return chrec_dont_know;
if (flags & FOLD_CONVERSIONS)
{
tree tmp = chrec_convert_aggressive (TREE_TYPE (chrec), op0);
if (tmp)
return tmp;
}
if (op0 == TREE_OPERAND (chrec, 0))
return chrec;
if (flags & FOLD_CONVERSIONS)
return fold_convert (TREE_TYPE (chrec), op0);
return chrec_convert (TREE_TYPE (chrec), op0, NULL_TREE);
case SCEV_NOT_KNOWN:
return chrec_dont_know;
case SCEV_KNOWN:
return chrec_known;
default:
break;
}
switch (TREE_CODE_LENGTH (TREE_CODE (chrec)))
{
case 3:
op0 = instantiate_parameters_1 (loop, TREE_OPERAND (chrec, 0),
flags, cache, size_expr);
if (op0 == chrec_dont_know)
return chrec_dont_know;
op1 = instantiate_parameters_1 (loop, TREE_OPERAND (chrec, 1),
flags, cache, size_expr);
if (op1 == chrec_dont_know)
return chrec_dont_know;
op2 = instantiate_parameters_1 (loop, TREE_OPERAND (chrec, 2),
flags, cache, size_expr);
if (op2 == chrec_dont_know)
return chrec_dont_know;
if (op0 == TREE_OPERAND (chrec, 0)
&& op1 == TREE_OPERAND (chrec, 1)
&& op2 == TREE_OPERAND (chrec, 2))
return chrec;
return fold_build3 (TREE_CODE (chrec),
TREE_TYPE (chrec), op0, op1, op2);
case 2:
op0 = instantiate_parameters_1 (loop, TREE_OPERAND (chrec, 0),
flags, cache, size_expr);
if (op0 == chrec_dont_know)
return chrec_dont_know;
op1 = instantiate_parameters_1 (loop, TREE_OPERAND (chrec, 1),
flags, cache, size_expr);
if (op1 == chrec_dont_know)
return chrec_dont_know;
if (op0 == TREE_OPERAND (chrec, 0)
&& op1 == TREE_OPERAND (chrec, 1))
return chrec;
return fold_build2 (TREE_CODE (chrec), TREE_TYPE (chrec), op0, op1);
case 1:
op0 = instantiate_parameters_1 (loop, TREE_OPERAND (chrec, 0),
flags, cache, size_expr);
if (op0 == chrec_dont_know)
return chrec_dont_know;
if (op0 == TREE_OPERAND (chrec, 0))
return chrec;
return fold_build1 (TREE_CODE (chrec), TREE_TYPE (chrec), op0);
case 0:
return chrec;
default:
break;
}
return chrec_dont_know;
}
tree
instantiate_parameters (struct loop *loop,
tree chrec)
{
tree res;
htab_t cache = htab_create (10, hash_scev_info, eq_scev_info, del_scev_info);
if (dump_file && (dump_flags & TDF_DETAILS))
{
fprintf (dump_file, "(instantiate_parameters \n");
fprintf (dump_file, " (loop_nb = %d)\n", loop->num);
fprintf (dump_file, " (chrec = ");
print_generic_expr (dump_file, chrec, 0);
fprintf (dump_file, ")\n");
}
res = instantiate_parameters_1 (loop, chrec, INSERT_SUPERLOOP_CHRECS, cache,
0);
if (dump_file && (dump_flags & TDF_DETAILS))
{
fprintf (dump_file, " (res = ");
print_generic_expr (dump_file, res, 0);
fprintf (dump_file, "))\n");
}
htab_delete (cache);
return res;
}
static tree
resolve_mixers (struct loop *loop, tree chrec)
{
htab_t cache = htab_create (10, hash_scev_info, eq_scev_info, del_scev_info);
tree ret = instantiate_parameters_1 (loop, chrec, FOLD_CONVERSIONS, cache, 0);
htab_delete (cache);
return ret;
}
tree
number_of_iterations_in_loop (struct loop *loop)
{
tree res, type;
edge exit;
struct tree_niter_desc niter_desc;
res = loop->nb_iterations;
if (res)
return res;
res = chrec_dont_know;
if (dump_file && (dump_flags & TDF_DETAILS))
fprintf (dump_file, "(number_of_iterations_in_loop\n");
exit = loop->single_exit;
if (!exit)
goto end;
if (!number_of_iterations_exit (loop, exit, &niter_desc, false))
goto end;
type = TREE_TYPE (niter_desc.niter);
if (integer_nonzerop (niter_desc.may_be_zero))
res = build_int_cst (type, 0);
else if (integer_zerop (niter_desc.may_be_zero))
res = niter_desc.niter;
else
res = chrec_dont_know;
end:
return set_nb_iterations_in_loop (loop, res);
}
static void
number_of_iterations_for_all_loops (VEC(tree,heap) **exit_conditions)
{
unsigned int i;
unsigned nb_chrec_dont_know_loops = 0;
unsigned nb_static_loops = 0;
tree cond;
for (i = 0; VEC_iterate (tree, *exit_conditions, i, cond); i++)
{
tree res = number_of_iterations_in_loop (loop_containing_stmt (cond));
if (chrec_contains_undetermined (res))
nb_chrec_dont_know_loops++;
else
nb_static_loops++;
}
if (dump_file)
{
fprintf (dump_file, "\n(\n");
fprintf (dump_file, "-----------------------------------------\n");
fprintf (dump_file, "%d\tnb_chrec_dont_know_loops\n", nb_chrec_dont_know_loops);
fprintf (dump_file, "%d\tnb_static_loops\n", nb_static_loops);
fprintf (dump_file, "%d\tnb_total_loops\n", current_loops->num);
fprintf (dump_file, "-----------------------------------------\n");
fprintf (dump_file, ")\n\n");
print_loop_ir (dump_file);
}
}
struct chrec_stats
{
unsigned nb_chrecs;
unsigned nb_affine;
unsigned nb_affine_multivar;
unsigned nb_higher_poly;
unsigned nb_chrec_dont_know;
unsigned nb_undetermined;
};
static inline void
reset_chrecs_counters (struct chrec_stats *stats)
{
stats->nb_chrecs = 0;
stats->nb_affine = 0;
stats->nb_affine_multivar = 0;
stats->nb_higher_poly = 0;
stats->nb_chrec_dont_know = 0;
stats->nb_undetermined = 0;
}
static void
dump_chrecs_stats (FILE *file, struct chrec_stats *stats)
{
fprintf (file, "\n(\n");
fprintf (file, "-----------------------------------------\n");
fprintf (file, "%d\taffine univariate chrecs\n", stats->nb_affine);
fprintf (file, "%d\taffine multivariate chrecs\n", stats->nb_affine_multivar);
fprintf (file, "%d\tdegree greater than 2 polynomials\n",
stats->nb_higher_poly);
fprintf (file, "%d\tchrec_dont_know chrecs\n", stats->nb_chrec_dont_know);
fprintf (file, "-----------------------------------------\n");
fprintf (file, "%d\ttotal chrecs\n", stats->nb_chrecs);
fprintf (file, "%d\twith undetermined coefficients\n",
stats->nb_undetermined);
fprintf (file, "-----------------------------------------\n");
fprintf (file, "%d\tchrecs in the scev database\n",
(int) htab_elements (scalar_evolution_info));
fprintf (file, "%d\tsets in the scev database\n", nb_set_scev);
fprintf (file, "%d\tgets in the scev database\n", nb_get_scev);
fprintf (file, "-----------------------------------------\n");
fprintf (file, ")\n\n");
}
static void
gather_chrec_stats (tree chrec, struct chrec_stats *stats)
{
if (dump_file && (dump_flags & TDF_STATS))
{
fprintf (dump_file, "(classify_chrec ");
print_generic_expr (dump_file, chrec, 0);
fprintf (dump_file, "\n");
}
stats->nb_chrecs++;
if (chrec == NULL_TREE)
{
stats->nb_undetermined++;
return;
}
switch (TREE_CODE (chrec))
{
case POLYNOMIAL_CHREC:
if (evolution_function_is_affine_p (chrec))
{
if (dump_file && (dump_flags & TDF_STATS))
fprintf (dump_file, " affine_univariate\n");
stats->nb_affine++;
}
else if (evolution_function_is_affine_multivariate_p (chrec))
{
if (dump_file && (dump_flags & TDF_STATS))
fprintf (dump_file, " affine_multivariate\n");
stats->nb_affine_multivar++;
}
else
{
if (dump_file && (dump_flags & TDF_STATS))
fprintf (dump_file, " higher_degree_polynomial\n");
stats->nb_higher_poly++;
}
break;
default:
break;
}
if (chrec_contains_undetermined (chrec))
{
if (dump_file && (dump_flags & TDF_STATS))
fprintf (dump_file, " undetermined\n");
stats->nb_undetermined++;
}
if (dump_file && (dump_flags & TDF_STATS))
fprintf (dump_file, ")\n");
}
static void
analyze_scalar_evolution_for_all_loop_phi_nodes (VEC(tree,heap) **exit_conditions)
{
unsigned int i;
struct chrec_stats stats;
tree cond;
reset_chrecs_counters (&stats);
for (i = 0; VEC_iterate (tree, *exit_conditions, i, cond); i++)
{
struct loop *loop;
basic_block bb;
tree phi, chrec;
loop = loop_containing_stmt (cond);
bb = loop->header;
for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
if (is_gimple_reg (PHI_RESULT (phi)))
{
chrec = instantiate_parameters
(loop,
analyze_scalar_evolution (loop, PHI_RESULT (phi)));
if (dump_file && (dump_flags & TDF_STATS))
gather_chrec_stats (chrec, &stats);
}
}
if (dump_file && (dump_flags & TDF_STATS))
dump_chrecs_stats (dump_file, &stats);
}
static int
gather_stats_on_scev_database_1 (void **slot, void *stats)
{
struct scev_info_str *entry = (struct scev_info_str *) *slot;
gather_chrec_stats (entry->chrec, (struct chrec_stats *) stats);
return 1;
}
void
gather_stats_on_scev_database (void)
{
struct chrec_stats stats;
if (!dump_file)
return;
reset_chrecs_counters (&stats);
htab_traverse (scalar_evolution_info, gather_stats_on_scev_database_1,
&stats);
dump_chrecs_stats (dump_file, &stats);
}
static void
initialize_scalar_evolutions_analyzer (void)
{
if (chrec_dont_know == NULL_TREE)
{
chrec_not_analyzed_yet = NULL_TREE;
chrec_dont_know = make_node (SCEV_NOT_KNOWN);
chrec_known = make_node (SCEV_KNOWN);
TREE_TYPE (chrec_dont_know) = void_type_node;
TREE_TYPE (chrec_known) = void_type_node;
}
}
void
scev_initialize (struct loops *loops)
{
unsigned i;
current_loops = loops;
scalar_evolution_info = htab_create (100, hash_scev_info,
eq_scev_info, del_scev_info);
already_instantiated = BITMAP_ALLOC (NULL);
initialize_scalar_evolutions_analyzer ();
for (i = 1; i < loops->num; i++)
if (loops->parray[i])
loops->parray[i]->nb_iterations = NULL_TREE;
}
void
scev_reset (void)
{
unsigned i;
struct loop *loop;
if (!scalar_evolution_info || !current_loops)
return;
htab_empty (scalar_evolution_info);
for (i = 1; i < current_loops->num; i++)
{
loop = current_loops->parray[i];
if (loop)
loop->nb_iterations = NULL_TREE;
}
}
bool
simple_iv (struct loop *loop, tree stmt, tree op, affine_iv *iv,
bool allow_nonconstant_step)
{
basic_block bb = bb_for_stmt (stmt);
tree type, ev;
bool folded_casts;
iv->base = NULL_TREE;
iv->step = NULL_TREE;
iv->no_overflow = false;
type = TREE_TYPE (op);
if (TREE_CODE (type) != INTEGER_TYPE
&& TREE_CODE (type) != POINTER_TYPE)
return false;
ev = analyze_scalar_evolution_in_loop (loop, bb->loop_father, op,
&folded_casts);
if (chrec_contains_undetermined (ev))
return false;
if (tree_does_not_contain_chrecs (ev)
&& !chrec_contains_symbols_defined_in_loop (ev, loop->num))
{
iv->base = ev;
iv->no_overflow = true;
return true;
}
if (TREE_CODE (ev) != POLYNOMIAL_CHREC
|| CHREC_VARIABLE (ev) != (unsigned) loop->num)
return false;
iv->step = CHREC_RIGHT (ev);
if (allow_nonconstant_step)
{
if (tree_contains_chrecs (iv->step, NULL)
|| chrec_contains_symbols_defined_in_loop (iv->step, loop->num))
return false;
}
else if (TREE_CODE (iv->step) != INTEGER_CST)
return false;
iv->base = CHREC_LEFT (ev);
if (tree_contains_chrecs (iv->base, NULL)
|| chrec_contains_symbols_defined_in_loop (iv->base, loop->num))
return false;
iv->no_overflow = !folded_casts && TYPE_OVERFLOW_UNDEFINED (type);
return true;
}
void
scev_analysis (void)
{
VEC(tree,heap) *exit_conditions;
exit_conditions = VEC_alloc (tree, heap, 37);
select_loops_exit_conditions (current_loops, &exit_conditions);
if (dump_file && (dump_flags & TDF_STATS))
analyze_scalar_evolution_for_all_loop_phi_nodes (&exit_conditions);
number_of_iterations_for_all_loops (&exit_conditions);
VEC_free (tree, heap, exit_conditions);
}
void
scev_finalize (void)
{
htab_delete (scalar_evolution_info);
BITMAP_FREE (already_instantiated);
}
static bool
expression_expensive_p (tree expr)
{
return force_expr_to_var_cost (expr) >= target_spill_cost;
}
unsigned int
scev_const_prop (void)
{
basic_block bb;
tree name, phi, next_phi, type, ev;
struct loop *loop, *ex_loop;
bitmap ssa_names_to_remove = NULL;
unsigned i;
if (!current_loops)
return 0;
FOR_EACH_BB (bb)
{
loop = bb->loop_father;
for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
{
name = PHI_RESULT (phi);
if (!is_gimple_reg (name))
continue;
type = TREE_TYPE (name);
if (!POINTER_TYPE_P (type)
&& !INTEGRAL_TYPE_P (type))
continue;
ev = resolve_mixers (loop, analyze_scalar_evolution (loop, name));
if (!is_gimple_min_invariant (ev)
|| !may_propagate_copy (name, ev))
continue;
if (name != ev)
replace_uses_by (name, ev);
if (!ssa_names_to_remove)
ssa_names_to_remove = BITMAP_ALLOC (NULL);
bitmap_set_bit (ssa_names_to_remove, SSA_NAME_VERSION (name));
}
}
if (ssa_names_to_remove)
{
bitmap_iterator bi;
unsigned i;
EXECUTE_IF_SET_IN_BITMAP (ssa_names_to_remove, 0, i, bi)
{
name = ssa_name (i);
phi = SSA_NAME_DEF_STMT (name);
gcc_assert (TREE_CODE (phi) == PHI_NODE);
remove_phi_node (phi, NULL);
}
BITMAP_FREE (ssa_names_to_remove);
scev_reset ();
}
for (i = current_loops->num - 1; i > 0; i--)
{
edge exit;
tree def, rslt, ass, niter;
block_stmt_iterator bsi;
loop = current_loops->parray[i];
if (!loop)
continue;
exit = loop->single_exit;
if (!exit)
continue;
niter = number_of_iterations_in_loop (loop);
if (niter == chrec_dont_know
|| expression_expensive_p (niter))
continue;
if (!single_pred_p (exit->dest))
split_loop_exit_edge (exit);
tree_block_label (exit->dest);
bsi = bsi_after_labels (exit->dest);
ex_loop = superloop_at_depth (loop, exit->dest->loop_father->depth + 1);
for (phi = phi_nodes (exit->dest); phi; phi = next_phi)
{
next_phi = PHI_CHAIN (phi);
rslt = PHI_RESULT (phi);
def = PHI_ARG_DEF_FROM_EDGE (phi, exit);
if (!is_gimple_reg (def))
continue;
if (!POINTER_TYPE_P (TREE_TYPE (def))
&& !INTEGRAL_TYPE_P (TREE_TYPE (def)))
continue;
def = analyze_scalar_evolution_in_loop (ex_loop, loop, def, NULL);
def = compute_overall_effect_of_inner_loop (ex_loop, def);
if (!tree_does_not_contain_chrecs (def)
|| chrec_contains_symbols_defined_in_loop (def, ex_loop->num)
|| contains_abnormal_ssa_name_p (def))
continue;
def = unshare_expr (def);
SET_PHI_RESULT (phi, NULL_TREE);
remove_phi_node (phi, NULL_TREE);
ass = build2 (MODIFY_EXPR, void_type_node, rslt, NULL_TREE);
SSA_NAME_DEF_STMT (rslt) = ass;
{
block_stmt_iterator dest = bsi;
bsi_insert_before (&dest, ass, BSI_NEW_STMT);
def = force_gimple_operand_bsi (&dest, def, false, NULL_TREE);
}
TREE_OPERAND (ass, 1) = def;
update_stmt (ass);
}
}
return 0;
}