/* SSA Dominator optimizations for trees
- Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
+ Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
Free Software Foundation, Inc.
Contributed by Diego Novillo <dnovillo@redhat.com>
static VEC(expr_hash_elt_t,heap) *avail_exprs_stack;
-/* Stack of statements we need to rescan during finalization for newly
- exposed variables.
-
- Statement rescanning must occur after the current block's available
- expressions are removed from AVAIL_EXPRS. Else we may change the
- hash code for an expression and be unable to find/remove it from
- AVAIL_EXPRS. */
-typedef gimple *gimple_p;
-DEF_VEC_P(gimple_p);
-DEF_VEC_ALLOC_P(gimple_p,heap);
-
-static VEC(gimple_p,heap) *stmts_to_rescan;
-
/* Structure for entries in the expression hash table. */
struct expr_hash_elt
static struct opt_stats_d opt_stats;
/* Local functions. */
-static void optimize_stmt (struct dom_walk_data *,
- basic_block,
- gimple_stmt_iterator);
+static void optimize_stmt (basic_block, gimple_stmt_iterator);
static tree lookup_avail_expr (gimple, bool);
static hashval_t avail_expr_hash (const void *);
static hashval_t real_avail_expr_hash (const void *);
static void record_equality (tree, tree);
static void record_equivalences_from_phis (basic_block);
static void record_equivalences_from_incoming_edge (basic_block);
-static bool eliminate_redundant_computations (gimple_stmt_iterator *);
+static void eliminate_redundant_computations (gimple_stmt_iterator *);
static void record_equivalences_from_stmt (gimple, int);
static void dom_thread_across_edge (struct dom_walk_data *, edge);
-static void dom_opt_finalize_block (struct dom_walk_data *, basic_block);
-static void dom_opt_initialize_block (struct dom_walk_data *, basic_block);
-static void propagate_to_outgoing_edges (struct dom_walk_data *, basic_block);
+static void dom_opt_leave_block (struct dom_walk_data *, basic_block);
+static void dom_opt_enter_block (struct dom_walk_data *, basic_block);
static void remove_local_expressions_from_table (void);
static void restore_vars_to_original_value (void);
static edge single_incoming_edge_ignoring_loop_edges (basic_block);
tree_ssa_dominator_optimize (void)
{
struct dom_walk_data walk_data;
- unsigned int i;
memset (&opt_stats, 0, sizeof (opt_stats));
avail_exprs = htab_create (1024, real_avail_expr_hash, avail_expr_eq, free_expr_hash_elt);
avail_exprs_stack = VEC_alloc (expr_hash_elt_t, heap, 20);
const_and_copies_stack = VEC_alloc (tree, heap, 20);
- stmts_to_rescan = VEC_alloc (gimple_p, heap, 20);
need_eh_cleanup = BITMAP_ALLOC (NULL);
/* Setup callbacks for the generic dominator tree walker. */
- walk_data.walk_stmts_backward = false;
walk_data.dom_direction = CDI_DOMINATORS;
walk_data.initialize_block_local_data = NULL;
- walk_data.before_dom_children_before_stmts = dom_opt_initialize_block;
- walk_data.before_dom_children_walk_stmts = optimize_stmt;
- walk_data.before_dom_children_after_stmts = propagate_to_outgoing_edges;
- walk_data.after_dom_children_before_stmts = NULL;
- walk_data.after_dom_children_walk_stmts = NULL;
- walk_data.after_dom_children_after_stmts = dom_opt_finalize_block;
+ walk_data.before_dom_children = dom_opt_enter_block;
+ walk_data.after_dom_children = dom_opt_leave_block;
/* Right now we only attach a dummy COND_EXPR to the global data pointer.
When we attach more stuff we'll need to fill this out with a real
structure. */
walk_data.global_data = NULL;
walk_data.block_local_data_size = 0;
- walk_data.interesting_blocks = NULL;
/* Now initialize the dominator walker. */
init_walk_dominator_tree (&walk_data);
that we update the loop info. */
loop_optimizer_init (LOOPS_HAVE_SIMPLE_LATCHES);
+ /* Initialize the value-handle array. */
+ threadedge_initialize_values ();
+
/* We need accurate information regarding back edges in the CFG
for jump threading; this may include back edges that are not part of
a single loop. */
bitmap_zero (need_eh_cleanup);
}
- /* Finally, remove everything except invariants in SSA_NAME_VALUE.
-
- Long term we will be able to let everything in SSA_NAME_VALUE
- persist. However, for now, we know this is the safe thing to do. */
- for (i = 0; i < num_ssa_names; i++)
- {
- tree name = ssa_name (i);
- tree value;
-
- if (!name)
- continue;
-
- value = SSA_NAME_VALUE (name);
- if (value && !is_gimple_min_invariant (value))
- SSA_NAME_VALUE (name) = NULL;
- }
-
statistics_counter_event (cfun, "Redundant expressions eliminated",
opt_stats.num_re);
statistics_counter_event (cfun, "Constants propagated",
VEC_free (expr_hash_elt_t, heap, avail_exprs_stack);
VEC_free (tree, heap, const_and_copies_stack);
- VEC_free (gimple_p, heap, stmts_to_rescan);
+ /* Free the value-handle array. */
+ threadedge_finalize_values ();
+ ssa_name_values = NULL;
+
return 0;
}
NULL, /* next */
0, /* static_pass_number */
TV_TREE_SSA_DOMINATOR_OPTS, /* tv_id */
- PROP_cfg | PROP_ssa | PROP_alias, /* properties_required */
+ PROP_cfg | PROP_ssa, /* properties_required */
0, /* properties_provided */
0, /* properties_destroyed */
0, /* todo_flags_start */
upon entry to BB. Equivalences can come from the edge traversed to
reach BB or they may come from PHI nodes at the start of BB. */
-static void
-dom_opt_initialize_block (struct dom_walk_data *walk_data ATTRIBUTE_UNUSED,
- basic_block bb)
-{
- if (dump_file && (dump_flags & TDF_DETAILS))
- fprintf (dump_file, "\n\nOptimizing block #%d\n\n", bb->index);
-
- /* Push a marker on the stacks of local information so that we know how
- far to unwind when we finalize this block. */
- VEC_safe_push (expr_hash_elt_t, heap, avail_exprs_stack, NULL);
- VEC_safe_push (tree, heap, const_and_copies_stack, NULL_TREE);
-
- record_equivalences_from_incoming_edge (bb);
-
- /* PHI nodes can create equivalences too. */
- record_equivalences_from_phis (bb);
-}
-
/* Remove all the expressions in LOCALS from TABLE, stopping when there are
LIMIT entries left in LOCALs. */
}
prev_value = VEC_pop (tree, const_and_copies_stack);
- SSA_NAME_VALUE (dest) = prev_value;
+ set_ssa_name_value (dest, prev_value);
}
}
simplify_stmt_for_jump_threading);
}
-/* We have finished processing the dominator children of BB, perform
- any finalization actions in preparation for leaving this node in
- the dominator tree. */
-
-static void
-dom_opt_finalize_block (struct dom_walk_data *walk_data, basic_block bb)
-{
- gimple last;
-
- /* If we have an outgoing edge to a block with multiple incoming and
- outgoing edges, then we may be able to thread the edge, i.e., we
- may be able to statically determine which of the outgoing edges
- will be traversed when the incoming edge from BB is traversed. */
- if (single_succ_p (bb)
- && (single_succ_edge (bb)->flags & EDGE_ABNORMAL) == 0
- && potentially_threadable_block (single_succ (bb)))
- {
- dom_thread_across_edge (walk_data, single_succ_edge (bb));
- }
- else if ((last = last_stmt (bb))
- && gimple_code (last) == GIMPLE_COND
- && EDGE_COUNT (bb->succs) == 2
- && (EDGE_SUCC (bb, 0)->flags & EDGE_ABNORMAL) == 0
- && (EDGE_SUCC (bb, 1)->flags & EDGE_ABNORMAL) == 0)
- {
- edge true_edge, false_edge;
-
- extract_true_false_edges_from_block (bb, &true_edge, &false_edge);
-
- /* Only try to thread the edge if it reaches a target block with
- more than one predecessor and more than one successor. */
- if (potentially_threadable_block (true_edge->dest))
- {
- struct edge_info *edge_info;
- unsigned int i;
-
- /* Push a marker onto the available expression stack so that we
- unwind any expressions related to the TRUE arm before processing
- the false arm below. */
- VEC_safe_push (expr_hash_elt_t, heap, avail_exprs_stack, NULL);
- VEC_safe_push (tree, heap, const_and_copies_stack, NULL_TREE);
-
- edge_info = (struct edge_info *) true_edge->aux;
-
- /* If we have info associated with this edge, record it into
- our equivalence tables. */
- if (edge_info)
- {
- struct cond_equivalence *cond_equivalences = edge_info->cond_equivalences;
- tree lhs = edge_info->lhs;
- tree rhs = edge_info->rhs;
-
- /* If we have a simple NAME = VALUE equivalence, record it. */
- if (lhs && TREE_CODE (lhs) == SSA_NAME)
- record_const_or_copy (lhs, rhs);
-
- /* If we have 0 = COND or 1 = COND equivalences, record them
- into our expression hash tables. */
- if (cond_equivalences)
- for (i = 0; i < edge_info->max_cond_equivalences; i++)
- record_cond (&cond_equivalences[i]);
- }
-
- dom_thread_across_edge (walk_data, true_edge);
-
- /* And restore the various tables to their state before
- we threaded this edge. */
- remove_local_expressions_from_table ();
- }
-
- /* Similarly for the ELSE arm. */
- if (potentially_threadable_block (false_edge->dest))
- {
- struct edge_info *edge_info;
- unsigned int i;
-
- VEC_safe_push (tree, heap, const_and_copies_stack, NULL_TREE);
- edge_info = (struct edge_info *) false_edge->aux;
-
- /* If we have info associated with this edge, record it into
- our equivalence tables. */
- if (edge_info)
- {
- struct cond_equivalence *cond_equivalences = edge_info->cond_equivalences;
- tree lhs = edge_info->lhs;
- tree rhs = edge_info->rhs;
-
- /* If we have a simple NAME = VALUE equivalence, record it. */
- if (lhs && TREE_CODE (lhs) == SSA_NAME)
- record_const_or_copy (lhs, rhs);
-
- /* If we have 0 = COND or 1 = COND equivalences, record them
- into our expression hash tables. */
- if (cond_equivalences)
- for (i = 0; i < edge_info->max_cond_equivalences; i++)
- record_cond (&cond_equivalences[i]);
- }
-
- /* Now thread the edge. */
- dom_thread_across_edge (walk_data, false_edge);
-
- /* No need to remove local expressions from our tables
- or restore vars to their original value as that will
- be done immediately below. */
- }
- }
-
- remove_local_expressions_from_table ();
- restore_vars_to_original_value ();
-
- /* If we queued any statements to rescan in this block, then
- go ahead and rescan them now. */
- while (VEC_length (gimple_p, stmts_to_rescan) > 0)
- {
- gimple *stmt_p = VEC_last (gimple_p, stmts_to_rescan);
- gimple stmt = *stmt_p;
- basic_block stmt_bb = gimple_bb (stmt);
-
- if (stmt_bb != bb)
- break;
-
- VEC_pop (gimple_p, stmts_to_rescan);
- pop_stmt_changes (stmt_p);
- }
-}
-
/* PHI nodes can create equivalences too.
Ignoring any alternatives which are the same as the result, if
inferred from a comparison. All uses of this ssa name are dominated
by this assignment, so unwinding just costs time and space. */
if (i == gimple_phi_num_args (phi) && may_propagate_copy (lhs, rhs))
- SSA_NAME_VALUE (lhs) = rhs;
+ set_ssa_name_value (lhs, rhs);
}
}
static void
record_const_or_copy_1 (tree x, tree y, tree prev_x)
{
- SSA_NAME_VALUE (x) = y;
+ set_ssa_name_value (x, y);
if (dump_file && (dump_flags & TDF_DETAILS))
{
if (! gsi_end_p (gsi))
{
gimple stmt = gsi_stmt (gsi);
+ location_t loc = gimple_location (stmt);
if (gimple_code (stmt) == GIMPLE_SWITCH)
{
if (label != NULL && label != error_mark_node)
{
- tree x = fold_convert (TREE_TYPE (index), CASE_LOW (label));
+ tree x = fold_convert_loc (loc, TREE_TYPE (index),
+ CASE_LOW (label));
edge_info = allocate_edge_info (e);
edge_info->lhs = index;
edge_info->rhs = x;
|| is_gimple_min_invariant (op1)))
{
tree cond = build2 (code, boolean_type_node, op0, op1);
- tree inverted = invert_truthvalue (cond);
+ tree inverted = invert_truthvalue_loc (loc, cond);
struct edge_info *edge_info;
edge_info = allocate_edge_info (true_edge);
|| TREE_CODE (op1) == SSA_NAME))
{
tree cond = build2 (code, boolean_type_node, op0, op1);
- tree inverted = invert_truthvalue (cond);
+ tree inverted = invert_truthvalue_loc (loc, cond);
struct edge_info *edge_info;
edge_info = allocate_edge_info (true_edge);
}
}
-/* Propagate information from BB to its outgoing edges.
-
- This can include equivalence information implied by control statements
- at the end of BB and const/copy propagation into PHIs in BB's
- successor blocks. */
-
static void
-propagate_to_outgoing_edges (struct dom_walk_data *walk_data ATTRIBUTE_UNUSED,
- basic_block bb)
+dom_opt_enter_block (struct dom_walk_data *walk_data ATTRIBUTE_UNUSED,
+ basic_block bb)
{
+ gimple_stmt_iterator gsi;
+
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ fprintf (dump_file, "\n\nOptimizing block #%d\n\n", bb->index);
+
+ /* Push a marker on the stacks of local information so that we know how
+ far to unwind when we finalize this block. */
+ VEC_safe_push (expr_hash_elt_t, heap, avail_exprs_stack, NULL);
+ VEC_safe_push (tree, heap, const_and_copies_stack, NULL_TREE);
+
+ record_equivalences_from_incoming_edge (bb);
+
+ /* PHI nodes can create equivalences too. */
+ record_equivalences_from_phis (bb);
+
+ for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+ optimize_stmt (bb, gsi);
+
+ /* Now prepare to process dominated blocks. */
record_edge_info (bb);
cprop_into_successor_phis (bb);
}
+/* We have finished processing the dominator children of BB, perform
+ any finalization actions in preparation for leaving this node in
+ the dominator tree. */
+
+static void
+dom_opt_leave_block (struct dom_walk_data *walk_data, basic_block bb)
+{
+ gimple last;
+
+ /* If we have an outgoing edge to a block with multiple incoming and
+ outgoing edges, then we may be able to thread the edge, i.e., we
+ may be able to statically determine which of the outgoing edges
+ will be traversed when the incoming edge from BB is traversed. */
+ if (single_succ_p (bb)
+ && (single_succ_edge (bb)->flags & EDGE_ABNORMAL) == 0
+ && potentially_threadable_block (single_succ (bb)))
+ {
+ dom_thread_across_edge (walk_data, single_succ_edge (bb));
+ }
+ else if ((last = last_stmt (bb))
+ && gimple_code (last) == GIMPLE_COND
+ && EDGE_COUNT (bb->succs) == 2
+ && (EDGE_SUCC (bb, 0)->flags & EDGE_ABNORMAL) == 0
+ && (EDGE_SUCC (bb, 1)->flags & EDGE_ABNORMAL) == 0)
+ {
+ edge true_edge, false_edge;
+
+ extract_true_false_edges_from_block (bb, &true_edge, &false_edge);
+
+ /* Only try to thread the edge if it reaches a target block with
+ more than one predecessor and more than one successor. */
+ if (potentially_threadable_block (true_edge->dest))
+ {
+ struct edge_info *edge_info;
+ unsigned int i;
+
+ /* Push a marker onto the available expression stack so that we
+ unwind any expressions related to the TRUE arm before processing
+ the false arm below. */
+ VEC_safe_push (expr_hash_elt_t, heap, avail_exprs_stack, NULL);
+ VEC_safe_push (tree, heap, const_and_copies_stack, NULL_TREE);
+
+ edge_info = (struct edge_info *) true_edge->aux;
+
+ /* If we have info associated with this edge, record it into
+ our equivalence tables. */
+ if (edge_info)
+ {
+ struct cond_equivalence *cond_equivalences = edge_info->cond_equivalences;
+ tree lhs = edge_info->lhs;
+ tree rhs = edge_info->rhs;
+
+ /* If we have a simple NAME = VALUE equivalence, record it. */
+ if (lhs && TREE_CODE (lhs) == SSA_NAME)
+ record_const_or_copy (lhs, rhs);
+
+ /* If we have 0 = COND or 1 = COND equivalences, record them
+ into our expression hash tables. */
+ if (cond_equivalences)
+ for (i = 0; i < edge_info->max_cond_equivalences; i++)
+ record_cond (&cond_equivalences[i]);
+ }
+
+ dom_thread_across_edge (walk_data, true_edge);
+
+ /* And restore the various tables to their state before
+ we threaded this edge. */
+ remove_local_expressions_from_table ();
+ }
+
+ /* Similarly for the ELSE arm. */
+ if (potentially_threadable_block (false_edge->dest))
+ {
+ struct edge_info *edge_info;
+ unsigned int i;
+
+ VEC_safe_push (tree, heap, const_and_copies_stack, NULL_TREE);
+ edge_info = (struct edge_info *) false_edge->aux;
+
+ /* If we have info associated with this edge, record it into
+ our equivalence tables. */
+ if (edge_info)
+ {
+ struct cond_equivalence *cond_equivalences = edge_info->cond_equivalences;
+ tree lhs = edge_info->lhs;
+ tree rhs = edge_info->rhs;
+
+ /* If we have a simple NAME = VALUE equivalence, record it. */
+ if (lhs && TREE_CODE (lhs) == SSA_NAME)
+ record_const_or_copy (lhs, rhs);
+
+ /* If we have 0 = COND or 1 = COND equivalences, record them
+ into our expression hash tables. */
+ if (cond_equivalences)
+ for (i = 0; i < edge_info->max_cond_equivalences; i++)
+ record_cond (&cond_equivalences[i]);
+ }
+
+ /* Now thread the edge. */
+ dom_thread_across_edge (walk_data, false_edge);
+
+ /* No need to remove local expressions from our tables
+ or restore vars to their original value as that will
+ be done immediately below. */
+ }
+ }
+
+ remove_local_expressions_from_table ();
+ restore_vars_to_original_value ();
+}
+
/* Search for redundant computations in STMT. If any are found, then
replace them with the variable holding the result of the computation.
If safe, record this expression into the available expression hash
table. */
-static bool
+static void
eliminate_redundant_computations (gimple_stmt_iterator* gsi)
{
tree expr_type;
tree cached_lhs;
bool insert = true;
- bool retval = false;
bool assigns_var_p = false;
gimple stmt = gsi_stmt (*gsi);
if (! def
|| TREE_CODE (def) != SSA_NAME
|| SSA_NAME_OCCURS_IN_ABNORMAL_PHI (def)
- || !ZERO_SSA_OPERANDS (stmt, SSA_OP_VDEF)
+ || gimple_vdef (stmt)
/* Do not record equivalences for increments of ivs. This would create
overlapping live ranges for a very questionable gain. */
|| simple_iv_increment_p (stmt))
gcc_unreachable ();
if (!cached_lhs)
- return false;
+ return;
/* It is safe to ignore types here since we have already done
type checking in the hashing and equality routines. In fact
}
opt_stats.num_re++;
-
- if (TREE_CODE (cached_lhs) == ADDR_EXPR
- || (POINTER_TYPE_P (expr_type)
- && is_gimple_min_invariant (cached_lhs)))
- retval = true;
if (assigns_var_p
&& !useless_type_conversion_p (expr_type, TREE_TYPE (cached_lhs)))
itself. */
gimple_set_modified (gsi_stmt (*gsi), true);
}
- return retval;
-}
-
-/* Return true if statement GS is an assignment that peforms a useless
- type conversion. It is is intended to be a tuples analog of function
- tree_ssa_useless_type_conversion. */
-
-static bool
-gimple_assign_unary_useless_conversion_p (gimple gs)
-{
- if (is_gimple_assign (gs)
- && (CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (gs))
- || gimple_assign_rhs_code (gs) == VIEW_CONVERT_EXPR
- || gimple_assign_rhs_code (gs) == NON_LVALUE_EXPR))
- {
- tree lhs_type = TREE_TYPE (gimple_assign_lhs (gs));
- tree rhs_type = TREE_TYPE (gimple_assign_rhs1 (gs));
- return useless_type_conversion_p (lhs_type, rhs_type);
- }
-
- return false;
}
/* STMT, a GIMPLE_ASSIGN, may create certain equivalences, in either
lhs_code = TREE_CODE (lhs);
if (lhs_code == SSA_NAME
- && (gimple_assign_single_p (stmt)
- || gimple_assign_unary_useless_conversion_p (stmt)))
+ && gimple_assign_single_p (stmt))
{
tree rhs = gimple_assign_rhs1 (stmt);
- /* Strip away any useless type conversions. */
- STRIP_USELESS_TYPE_CONVERSION (rhs);
-
/* If the RHS of the assignment is a constant or another variable that
may be propagated, register it in the CONST_AND_COPIES table. We
do not need to record unwind data for this, since this is a true
fprintf (dump_file, "\n");
}
- SSA_NAME_VALUE (lhs) = rhs;
+ set_ssa_name_value (lhs, rhs);
}
}
else
new_stmt = gimple_build_assign (rhs, lhs);
- create_ssa_artificial_load_stmt (new_stmt, stmt, true);
+ gimple_set_vuse (new_stmt, gimple_vdef (stmt));
/* Finally enter the statement into the available expression
table. */
/* Replace *OP_P in STMT with any known equivalent value for *OP_P from
CONST_AND_COPIES. */
-static bool
+static void
cprop_operand (gimple stmt, use_operand_p op_p)
{
- bool may_have_exposed_new_symbols = false;
tree val;
tree op = USE_FROM_PTR (op_p);
&& (TREE_CODE (val) != SSA_NAME
|| is_gimple_reg (val)
|| get_virtual_var (val) != get_virtual_var (op)))
- return false;
+ return;
/* Do not replace hard register operands in asm statements. */
if (gimple_code (stmt) == GIMPLE_ASM
&& !may_propagate_copy_into_asm (op))
- return false;
+ return;
/* Certain operands are not allowed to be copy propagated due
to their interaction with exception handling and some GCC
extensions. */
if (!may_propagate_copy (op, val))
- return false;
+ return;
/* Do not propagate addresses that point to volatiles into memory
stmts without volatile operands. */
&& TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (val)))
&& gimple_has_mem_ops (stmt)
&& !gimple_has_volatile_ops (stmt))
- return false;
+ return;
/* Do not propagate copies if the propagated value is at a deeper loop
depth than the propagatee. Otherwise, this may move loop variant
opportunities. If the value was loop invariant, it will be hoisted
by LICM and exposed for copy propagation. */
if (loop_depth_of_name (val) > loop_depth_of_name (op))
- return false;
+ return;
+
+ /* Do not propagate copies into simple IV increment statements.
+ See PR23821 for how this can disturb IV analysis. */
+ if (TREE_CODE (val) != INTEGER_CST
+ && simple_iv_increment_p (stmt))
+ return;
/* Dump details. */
if (dump_file && (dump_flags & TDF_DETAILS))
fprintf (dump_file, "'\n");
}
- /* If VAL is an ADDR_EXPR or a constant of pointer type, note
- that we may have exposed a new symbol for SSA renaming. */
- if (TREE_CODE (val) == ADDR_EXPR
- || (POINTER_TYPE_P (TREE_TYPE (op))
- && is_gimple_min_invariant (val)))
- may_have_exposed_new_symbols = true;
-
if (TREE_CODE (val) != SSA_NAME)
opt_stats.num_const_prop++;
else
rescan the statement and rewrite its operands again. */
gimple_set_modified (stmt, true);
}
- return may_have_exposed_new_symbols;
}
/* CONST_AND_COPIES is a table which maps an SSA_NAME to the current
Propagate values from CONST_AND_COPIES into the uses, vuses and
vdef_ops of STMT. */
-static bool
+static void
cprop_into_stmt (gimple stmt)
{
- bool may_have_exposed_new_symbols = false;
use_operand_p op_p;
ssa_op_iter iter;
FOR_EACH_SSA_USE_OPERAND (op_p, stmt, iter, SSA_OP_ALL_USES)
{
if (TREE_CODE (USE_FROM_PTR (op_p)) == SSA_NAME)
- may_have_exposed_new_symbols |= cprop_operand (stmt, op_p);
+ cprop_operand (stmt, op_p);
}
-
- return may_have_exposed_new_symbols;
}
/* Optimize the statement pointed to by iterator SI.
the variable in the LHS in the CONST_AND_COPIES table. */
static void
-optimize_stmt (struct dom_walk_data *walk_data ATTRIBUTE_UNUSED,
- basic_block bb, gimple_stmt_iterator si)
+optimize_stmt (basic_block bb, gimple_stmt_iterator si)
{
gimple stmt, old_stmt;
bool may_optimize_p;
- bool may_have_exposed_new_symbols;
bool modified_p = false;
old_stmt = stmt = gsi_stmt (si);
update_stmt_if_modified (stmt);
opt_stats.num_stmts++;
- push_stmt_changes (gsi_stmt_ptr (&si));
if (dump_file && (dump_flags & TDF_DETAILS))
{
}
/* Const/copy propagate into USES, VUSES and the RHS of VDEFs. */
- may_have_exposed_new_symbols = cprop_into_stmt (stmt);
+ cprop_into_stmt (stmt);
/* If the statement has been modified with constant replacements,
fold its RHS before checking for redundant computations. */
if (rhs && TREE_CODE (rhs) == ADDR_EXPR)
recompute_tree_invariant_for_addr_expr (rhs);
- /* Constant/copy propagation above may change the set of
- virtual operands associated with this statement. Folding
- may remove the need for some virtual operands.
-
- Indicate we will need to rescan and rewrite the statement. */
- may_have_exposed_new_symbols = true;
/* Indicate that maybe_clean_or_replace_eh_stmt needs to be called,
even if fold_stmt updated the stmt already and thus cleared
gimple_modified_p flag on it. */
if (may_optimize_p)
{
- may_have_exposed_new_symbols |= eliminate_redundant_computations (&si);
+ eliminate_redundant_computations (&si);
stmt = gsi_stmt (si);
+ if (gimple_code (stmt) == GIMPLE_CALL)
+ {
+ /* Resolve __builtin_constant_p. If it hasn't been
+ folded to integer_one_node by now, it's fairly
+ certain that the value simply isn't constant. */
+ tree callee = gimple_call_fndecl (stmt);
+ if (callee
+ && DECL_BUILT_IN_CLASS (callee) == BUILT_IN_NORMAL
+ && DECL_FUNCTION_CODE (callee) == BUILT_IN_CONSTANT_P)
+ {
+ propagate_tree_value_into_stmt (&si, integer_zero_node);
+ stmt = gsi_stmt (si);
+ }
+ }
}
/* Record any additional equivalences created by this statement. */
if (gimple_modified_p (stmt) || modified_p)
{
tree val = NULL;
+
+ update_stmt (stmt);
if (gimple_code (stmt) == GIMPLE_COND)
- val = fold_binary (gimple_cond_code (stmt), boolean_type_node,
+ val = fold_binary_loc (gimple_location (stmt),
+ gimple_cond_code (stmt), boolean_type_node,
gimple_cond_lhs (stmt), gimple_cond_rhs (stmt));
else if (gimple_code (stmt) == GIMPLE_SWITCH)
val = gimple_switch_index (stmt);
fprintf (dump_file, " Flagged to clear EH edges.\n");
}
}
-
- if (may_have_exposed_new_symbols)
- {
- /* Queue the statement to be re-scanned after all the
- AVAIL_EXPRS have been processed. The change buffer stack for
- all the pushed statements will be processed when this queue
- is emptied. */
- VEC_safe_push (gimple_p, heap, stmts_to_rescan, gsi_stmt_ptr (&si));
- }
- else
- {
- /* Otherwise, just discard the recently pushed change buffer. If
- not, the STMTS_TO_RESCAN queue will get out of synch with the
- change buffer stack. */
- discard_stmt_changes (gsi_stmt_ptr (&si));
- }
}
/* Search for an existing instance of STMT in the AVAIL_EXPRS table.
gimple stmt = ((const struct expr_hash_elt *)p)->stmt;
const struct hashable_expr *expr = &((const struct expr_hash_elt *)p)->expr;
tree vuse;
- ssa_op_iter iter;
hashval_t val = 0;
val = iterative_hash_hashable_expr (expr, val);
if (!stmt)
return val;
- /* Add the SSA version numbers of every vuse operand. This is important
+ /* Add the SSA version numbers of the vuse operand. This is important
because compound variables like arrays are not renamed in the
operands. Rather, the rename is done on the virtual variable
representing all the elements of the array. */
- FOR_EACH_SSA_TREE_OPERAND (vuse, stmt, iter, SSA_OP_VUSE)
+ if ((vuse = gimple_vuse (stmt)))
val = iterative_hash_expr (vuse, val);
return val;
&& types_compatible_p (expr1->type, expr2->type))
{
/* Note that STMT1 and/or STMT2 may be NULL. */
- bool ret = compare_ssa_operands_equal (stmt1, stmt2, SSA_OP_VUSE);
- return ret;
+ return ((stmt1 ? gimple_vuse (stmt1) : NULL_TREE)
+ == (stmt2 ? gimple_vuse (stmt2) : NULL_TREE));
}
return false;
/* Given PHI, return its RHS if the PHI is a degenerate, otherwise return
NULL. */
-static tree
+tree
degenerate_phi_result (gimple phi)
{
tree lhs = gimple_phi_result (phi);
be successful would be if the use occurs in an ASM_EXPR. */
FOR_EACH_IMM_USE_STMT (use_stmt, iter, lhs)
{
+ /* Leave debug stmts alone. If we succeed in propagating
+ all non-debug uses, we'll drop the DEF, and propagation
+ into debug stmts will occur then. */
+ if (gimple_debug_bind_p (use_stmt))
+ continue;
/* It's not always safe to propagate into an ASM_EXPR. */
if (gimple_code (use_stmt) == GIMPLE_ASM
print_gimple_stmt (dump_file, use_stmt, 0, dump_flags);
}
- push_stmt_changes (&use_stmt);
-
/* Propagate the RHS into this use of the LHS. */
FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
propagate_value (use_p, rhs);
bitmap_set_bit (interesting_names, SSA_NAME_VERSION (result));
}
- discard_stmt_changes (&use_stmt);
continue;
}
fold_stmt_inplace (use_stmt);
/* Sometimes propagation can expose new operands to the
- renamer. Note this will call update_stmt at the
- appropriate time. */
- pop_stmt_changes (&use_stmt);
+ renamer. */
+ update_stmt (use_stmt);
/* Dump details. */
if (dump_file && (dump_flags & TDF_DETAILS))
tree val;
if (gimple_code (use_stmt) == GIMPLE_COND)
- val = fold_binary (gimple_cond_code (use_stmt),
+ val = fold_binary_loc (gimple_location (use_stmt),
+ gimple_cond_code (use_stmt),
boolean_type_node,
gimple_cond_lhs (use_stmt),
gimple_cond_rhs (use_stmt));
NULL, /* next */
0, /* static_pass_number */
TV_TREE_PHI_CPROP, /* tv_id */
- PROP_cfg | PROP_ssa | PROP_alias, /* properties_required */
+ PROP_cfg | PROP_ssa, /* properties_required */
0, /* properties_provided */
0, /* properties_destroyed */
0, /* todo_flags_start */
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