edge
ssa_redirect_edge (edge e, basic_block dest)
{
- tree phi, next;
+ tree phi;
tree list = NULL, *last = &list;
tree src, dst, node;
/* Remove the appropriate PHI arguments in E's destination block. */
- for (phi = phi_nodes (e->dest); phi; phi = next)
+ for (phi = phi_nodes (e->dest); phi; phi = PHI_CHAIN (phi))
{
- next = PHI_CHAIN (phi);
-
if (PHI_ARG_DEF (phi, e->dest_idx) == NULL_TREE)
continue;
return true;
}
+ if (is_virtual && var_ann (SSA_NAME_VAR (ssa_name))
+ && get_subvars_for_var (SSA_NAME_VAR (ssa_name)) != NULL)
+ {
+ error ("Found real variable when subvariables should have appeared");
+ return true;
+ }
+
return false;
}
that are defined before STMT in basic block BB. */
static bool
-verify_use (basic_block bb, basic_block def_bb, tree ssa_name,
+verify_use (basic_block bb, basic_block def_bb, use_operand_p use_p,
tree stmt, bool check_abnormal, bool is_virtual,
bitmap names_defined_in_bb)
{
bool err = false;
+ tree ssa_name = USE_FROM_PTR (use_p);
err = verify_ssa_name (ssa_name, is_virtual);
+
+ if (!TREE_VISITED (ssa_name))
+ if (verify_imm_links (stderr, ssa_name))
+ err = true;
+
TREE_VISITED (ssa_name) = 1;
if (IS_EMPTY_STMT (SSA_NAME_DEF_STMT (ssa_name))
err = true;
}
+ /* Make sure the use is in an appropriate list by checking the previous
+ element to make sure it's the same. */
+ if (use_p->prev == NULL)
+ {
+ error ("No immediate_use list");
+ err = true;
+ }
+ else
+ {
+ tree listvar ;
+ if (use_p->prev->use == NULL)
+ listvar = use_p->prev->stmt;
+ else
+ listvar = USE_FROM_PTR (use_p->prev);
+ if (listvar != ssa_name)
+ {
+ error ("Wrong immediate use list");
+ err = true;
+ }
+ }
+
if (err)
{
fprintf (stderr, "for SSA_NAME: ");
print_generic_expr (stderr, ssa_name, TDF_VOPS);
- fprintf (stderr, "in statement:\n");
+ fprintf (stderr, " in statement:\n");
print_generic_stmt (stderr, stmt, TDF_VOPS);
}
for (i = 0; i < phi_num_args; i++)
{
- tree op = PHI_ARG_DEF (phi, i);
+ use_operand_p op_p = PHI_ARG_DEF_PTR (phi, i);
+ tree op = USE_FROM_PTR (op_p);
+
e = EDGE_PRED (bb, i);
}
if (TREE_CODE (op) == SSA_NAME)
- err = verify_use (e->src, definition_block[SSA_NAME_VERSION (op)], op,
+ err = verify_use (e->src, definition_block[SSA_NAME_VERSION (op)], op_p,
phi, e->flags & EDGE_ABNORMAL,
!is_gimple_reg (PHI_RESULT (phi)),
NULL);
TODO: verify the variable annotations. */
void
-verify_ssa (void)
+verify_ssa (bool check_modified_stmt)
{
size_t i;
basic_block bb;
for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi))
{
tree stmt = bsi_stmt (bsi);
+ use_operand_p use_p;
- get_stmt_operands (stmt);
+ if (check_modified_stmt && stmt_modified_p (stmt))
+ {
+ error ("Stmt (0x%x) marked modified after optimization pass : ",
+ (unsigned long)stmt);
+ print_generic_stmt (stderr, stmt, TDF_VOPS);
+ goto err;
+ }
+
+ if (TREE_CODE (stmt) == MODIFY_EXPR
+ && TREE_CODE (TREE_OPERAND (stmt, 0)) != SSA_NAME)
+ {
+ tree lhs, base_address;
+
+ lhs = TREE_OPERAND (stmt, 0);
+ base_address = get_base_address (lhs);
- if (stmt_ann (stmt)->makes_aliased_stores
- && NUM_V_MAY_DEFS (STMT_V_MAY_DEF_OPS (stmt)) == 0)
+ if (base_address
+ && SSA_VAR_P (base_address)
+ && NUM_V_MAY_DEFS (STMT_V_MAY_DEF_OPS (stmt)) == 0
+ && NUM_V_MUST_DEFS (STMT_V_MUST_DEF_OPS (stmt)) == 0)
{
- error ("Statement makes aliased stores, but has no V_MAY_DEFS");
+ error ("Statement makes a memory store, but has no "
+ "V_MAY_DEFS nor V_MUST_DEFS");
print_generic_stmt (stderr, stmt, TDF_VOPS);
goto err;
}
+ }
+
- FOR_EACH_SSA_TREE_OPERAND (op, stmt, iter, SSA_OP_ALL_USES | SSA_OP_ALL_KILLS)
+ if (stmt_ann (stmt)->makes_aliased_stores
+ && NUM_V_MAY_DEFS (STMT_V_MAY_DEF_OPS (stmt)) == 0)
{
+ error ("Statement makes aliased stores, but has no V_MAY_DEFS");
+ print_generic_stmt (stderr, stmt, TDF_VOPS);
+ goto err;
+ }
+
+ FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter,
+ SSA_OP_ALL_USES | SSA_OP_ALL_KILLS)
+ {
+ op = USE_FROM_PTR (use_p);
if (verify_use (bb, definition_block[SSA_NAME_VERSION (op)],
- op, stmt, false, !is_gimple_reg (op),
+ use_p, stmt, false, !is_gimple_reg (op),
names_defined_in_bb))
goto err;
}
VARRAY_TREE_INIT (referenced_vars, 20, "referenced_vars");
call_clobbered_vars = BITMAP_ALLOC (NULL);
addressable_vars = BITMAP_ALLOC (NULL);
- init_ssa_operands ();
init_ssanames ();
init_phinodes ();
global_var = NULL_TREE;
+ aliases_computed_p = false;
}
fini_ssanames ();
fini_phinodes ();
- fini_ssa_operands ();
global_var = NULL_TREE;
BITMAP_FREE (call_clobbered_vars);
BITMAP_FREE (addressable_vars);
addressable_vars = NULL;
modified_noreturn_calls = NULL;
+ aliases_computed_p = false;
}
bool
tree_ssa_useless_type_conversion_1 (tree outer_type, tree inner_type)
{
+ if (inner_type == outer_type)
+ return true;
+
+ /* Changes in machine mode are never useless conversions. */
+ if (TYPE_MODE (inner_type) != TYPE_MODE (outer_type))
+ return false;
+
/* If the inner and outer types are effectively the same, then
strip the type conversion and enter the equivalence into
the table. */
- if (inner_type == outer_type
- || (lang_hooks.types_compatible_p (inner_type, outer_type)))
+ if (lang_hooks.types_compatible_p (inner_type, outer_type))
return true;
/* If both types are pointers and the outer type is a (void *), then
implement the ABI. */
else if (POINTER_TYPE_P (inner_type)
&& POINTER_TYPE_P (outer_type)
- && TYPE_MODE (inner_type) == TYPE_MODE (outer_type)
&& TYPE_REF_CAN_ALIAS_ALL (inner_type)
== TYPE_REF_CAN_ALIAS_ALL (outer_type)
&& TREE_CODE (TREE_TYPE (outer_type)) == VOID_TYPE)
so strip conversions that just switch between them. */
else if (POINTER_TYPE_P (inner_type)
&& POINTER_TYPE_P (outer_type)
- && TYPE_MODE (inner_type) == TYPE_MODE (outer_type)
&& TYPE_REF_CAN_ALIAS_ALL (inner_type)
== TYPE_REF_CAN_ALIAS_ALL (outer_type)
&& lang_hooks.types_compatible_p (TREE_TYPE (inner_type),
mean that testing of precision is necessary. */
else if (INTEGRAL_TYPE_P (inner_type)
&& INTEGRAL_TYPE_P (outer_type)
- && TYPE_MODE (inner_type) == TYPE_MODE (outer_type)
&& TYPE_UNSIGNED (inner_type) == TYPE_UNSIGNED (outer_type)
&& TYPE_PRECISION (inner_type) == TYPE_PRECISION (outer_type))
{
bool
stmt_references_memory_p (tree stmt)
{
- stmt_ann_t ann;
-
- get_stmt_operands (stmt);
- ann = stmt_ann (stmt);
+ stmt_ann_t ann = stmt_ann (stmt);
if (ann->has_volatile_ops)
return true;
}
}
-
-/* Replaces VAR with REPL in memory reference expression *X in
- statement STMT. */
-
-static void
-propagate_into_addr (tree stmt, tree var, tree *x, tree repl)
-{
- tree new_var, ass_stmt, addr_var;
- basic_block bb;
- block_stmt_iterator bsi;
-
- /* There is nothing special to handle in the other cases. */
- if (TREE_CODE (repl) != ADDR_EXPR)
- return;
- addr_var = TREE_OPERAND (repl, 0);
-
- while (handled_component_p (*x)
- || TREE_CODE (*x) == REALPART_EXPR
- || TREE_CODE (*x) == IMAGPART_EXPR)
- x = &TREE_OPERAND (*x, 0);
-
- if (TREE_CODE (*x) != INDIRECT_REF
- || TREE_OPERAND (*x, 0) != var)
- return;
-
- if (TREE_TYPE (*x) == TREE_TYPE (addr_var))
- {
- *x = addr_var;
- mark_new_vars_to_rename (stmt, vars_to_rename);
- return;
- }
-
-
- /* Frontends sometimes produce expressions like *&a instead of a[0].
- Create a temporary variable to handle this case. */
- ass_stmt = build2 (MODIFY_EXPR, void_type_node, NULL_TREE, repl);
- new_var = duplicate_ssa_name (var, ass_stmt);
- TREE_OPERAND (*x, 0) = new_var;
- TREE_OPERAND (ass_stmt, 0) = new_var;
-
- bb = bb_for_stmt (stmt);
- tree_block_label (bb);
- bsi = bsi_after_labels (bb);
- bsi_insert_after (&bsi, ass_stmt, BSI_NEW_STMT);
-
- mark_new_vars_to_rename (stmt, vars_to_rename);
-}
-
-/* Replaces immediate uses of VAR by REPL. */
-
-static void
-replace_immediate_uses (tree var, tree repl)
-{
- int i, j, n;
- dataflow_t df;
- tree stmt;
- bool mark_new_vars;
- ssa_op_iter iter;
- use_operand_p use_p;
-
- df = get_immediate_uses (SSA_NAME_DEF_STMT (var));
- n = num_immediate_uses (df);
-
- for (i = 0; i < n; i++)
- {
- stmt = immediate_use (df, i);
-
- if (TREE_CODE (stmt) == PHI_NODE)
- {
- for (j = 0; j < PHI_NUM_ARGS (stmt); j++)
- if (PHI_ARG_DEF (stmt, j) == var)
- {
- SET_PHI_ARG_DEF (stmt, j, repl);
- if (TREE_CODE (repl) == SSA_NAME
- && PHI_ARG_EDGE (stmt, j)->flags & EDGE_ABNORMAL)
- SSA_NAME_OCCURS_IN_ABNORMAL_PHI (repl) = 1;
- }
-
- continue;
- }
-
- get_stmt_operands (stmt);
- mark_new_vars = false;
- if (is_gimple_reg (SSA_NAME_VAR (var)))
- {
- if (TREE_CODE (stmt) == MODIFY_EXPR)
- {
- propagate_into_addr (stmt, var, &TREE_OPERAND (stmt, 0), repl);
- propagate_into_addr (stmt, var, &TREE_OPERAND (stmt, 1), repl);
- }
-
- FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter, SSA_OP_USE)
- if (USE_FROM_PTR (use_p) == var)
- {
- propagate_value (use_p, repl);
- mark_new_vars = POINTER_TYPE_P (TREE_TYPE (repl));
- }
- }
- else
- {
- FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter,
- SSA_OP_VIRTUAL_USES | SSA_OP_VIRTUAL_KILLS)
- if (USE_FROM_PTR (use_p) == var)
- propagate_value (use_p, repl);
- }
-
- /* FIXME. If REPL is a constant, we need to fold STMT.
- However, fold_stmt wants a pointer to the statement, because
- it may happen that it needs to replace the whole statement
- with a new expression. Since the current def-use machinery
- does not return pointers to statements, we call fold_stmt
- with the address of a local temporary, if that call changes
- the temporary then we fallback on looking for a proper
- pointer to STMT by scanning STMT's basic block.
-
- Note that all this will become unnecessary soon. This
- pass is being replaced with a proper copy propagation pass
- for 4.1 (dnovillo, 2004-09-17). */
- if (TREE_CODE (repl) != SSA_NAME)
- {
- tree tmp = stmt;
- fold_stmt (&tmp);
- mark_new_vars = true;
- if (tmp != stmt)
- {
- block_stmt_iterator si = bsi_for_stmt (stmt);
- mark_new_vars_to_rename (tmp, vars_to_rename);
- redirect_immediate_uses (stmt, tmp);
- bsi_replace (&si, tmp, true);
- stmt = bsi_stmt (si);
- }
- }
-
- /* If REPL is a pointer, it may have different memory tags associated
- with it. For instance, VAR may have had a name tag while REPL
- only had a type tag. In these cases, the virtual operands (if
- any) in the statement will refer to different symbols which need
- to be renamed. */
- if (mark_new_vars)
- mark_new_vars_to_rename (stmt, vars_to_rename);
- else
- modify_stmt (stmt);
- }
-}
-
-/* Gets the value VAR is equivalent to according to EQ_TO. */
-
-static tree
-get_eq_name (tree *eq_to, tree var)
-{
- unsigned ver;
- tree val = var;
-
- while (TREE_CODE (val) == SSA_NAME)
- {
- ver = SSA_NAME_VERSION (val);
- if (!eq_to[ver])
- break;
-
- val = eq_to[ver];
- }
-
- while (TREE_CODE (var) == SSA_NAME)
- {
- ver = SSA_NAME_VERSION (var);
- if (!eq_to[ver])
- break;
-
- var = eq_to[ver];
- eq_to[ver] = val;
- }
-
- return val;
-}
-
-/* Checks whether phi node PHI is redundant and if it is, records the ssa name
- its result is redundant to to EQ_TO array. */
-
-static void
-check_phi_redundancy (tree phi, tree *eq_to)
-{
- tree val = NULL_TREE, def, res = PHI_RESULT (phi), stmt;
- unsigned i, ver = SSA_NAME_VERSION (res), n;
- dataflow_t df;
-
- /* It is unlikely that such large phi node would be redundant. */
- if (PHI_NUM_ARGS (phi) > 16)
- return;
-
- for (i = 0; i < (unsigned) PHI_NUM_ARGS (phi); i++)
- {
- def = PHI_ARG_DEF (phi, i);
-
- if (TREE_CODE (def) == SSA_NAME)
- {
- def = get_eq_name (eq_to, def);
- if (def == res)
- continue;
- }
-
- if (val
- && !operand_equal_for_phi_arg_p (val, def))
- return;
-
- val = def;
- }
-
- /* At least one of the arguments should not be equal to the result, or
- something strange is happening. */
- gcc_assert (val);
-
- if (get_eq_name (eq_to, res) == val)
- return;
-
- if (!may_propagate_copy (res, val))
- return;
-
- eq_to[ver] = val;
-
- df = get_immediate_uses (SSA_NAME_DEF_STMT (res));
- n = num_immediate_uses (df);
-
- for (i = 0; i < n; i++)
- {
- stmt = immediate_use (df, i);
-
- if (TREE_CODE (stmt) == PHI_NODE)
- check_phi_redundancy (stmt, eq_to);
- }
-}
-
-/* Removes redundant phi nodes.
-
- A redundant PHI node is a PHI node where all of its PHI arguments
- are the same value, excluding any PHI arguments which are the same
- as the PHI result.
-
- A redundant PHI node is effectively a copy, so we forward copy propagate
- which removes all uses of the destination of the PHI node then
- finally we delete the redundant PHI node.
-
- Note that if we can not copy propagate the PHI node, then the PHI
- will not be removed. Thus we do not have to worry about dependencies
- between PHIs and the problems serializing PHIs into copies creates.
-
- The most important effect of this pass is to remove degenerate PHI
- nodes created by removing unreachable code. */
-
-void
-kill_redundant_phi_nodes (void)
-{
- tree *eq_to;
- unsigned i, old_num_ssa_names;
- basic_block bb;
- tree phi, var, repl, stmt;
-
- /* The EQ_TO[VER] holds the value by that the ssa name VER should be
- replaced. If EQ_TO[VER] is ssa name and it is decided to replace it by
- other value, it may be necessary to follow the chain till the final value.
- We perform path shortening (replacing the entries of the EQ_TO array with
- heads of these chains) whenever we access the field to prevent quadratic
- complexity (probably would not occur in practice anyway, but let us play
- it safe). */
- eq_to = xcalloc (num_ssa_names, sizeof (tree));
-
- /* We have had cases where computing immediate uses takes a
- significant amount of compile time. If we run into such
- problems here, we may want to only compute immediate uses for
- a subset of all the SSA_NAMEs instead of computing it for
- all of the SSA_NAMEs. */
- compute_immediate_uses (TDFA_USE_OPS | TDFA_USE_VOPS, NULL);
- old_num_ssa_names = num_ssa_names;
-
- FOR_EACH_BB (bb)
- {
- for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
- {
- var = PHI_RESULT (phi);
- check_phi_redundancy (phi, eq_to);
- }
- }
-
- /* Now propagate the values. */
- for (i = 0; i < old_num_ssa_names; i++)
- {
- if (!ssa_name (i))
- continue;
-
- repl = get_eq_name (eq_to, ssa_name (i));
- if (repl != ssa_name (i))
- replace_immediate_uses (ssa_name (i), repl);
- }
-
- /* And remove the dead phis. */
- for (i = 0; i < old_num_ssa_names; i++)
- {
- if (!ssa_name (i))
- continue;
-
- repl = get_eq_name (eq_to, ssa_name (i));
- if (repl != ssa_name (i))
- {
- stmt = SSA_NAME_DEF_STMT (ssa_name (i));
- remove_phi_node (stmt, NULL_TREE, bb_for_stmt (stmt));
- }
- }
-
- free_df ();
- free (eq_to);
-}
-
-struct tree_opt_pass pass_redundant_phi =
-{
- "redphi", /* name */
- NULL, /* gate */
- kill_redundant_phi_nodes, /* execute */
- NULL, /* sub */
- NULL, /* next */
- 0, /* static_pass_number */
- TV_TREE_REDPHI, /* tv_id */
- PROP_cfg | PROP_ssa | PROP_alias, /* properties_required */
- 0, /* properties_provided */
- 0, /* properties_destroyed */
- 0, /* todo_flags_start */
- TODO_dump_func | TODO_rename_vars
- | TODO_ggc_collect | TODO_verify_ssa, /* todo_flags_finish */
- 0 /* letter */
-};
\f
/* Emit warnings for uninitialized variables. This is done in two passes.
warning text is in MSGID and LOCUS may contain a location or be null. */
static void
-warn_uninit (tree t, const char *msgid, location_t *locus)
+warn_uninit (tree t, const char *msgid, void *data)
{
tree var = SSA_NAME_VAR (t);
tree def = SSA_NAME_DEF_STMT (t);
+ tree context = (tree) data;
+ location_t * locus;
/* Default uses (indicated by an empty definition statement),
are uninitialized. */
if (TREE_NO_WARNING (var))
return;
- if (!locus)
- locus = &DECL_SOURCE_LOCATION (var);
+ locus = (context != NULL && EXPR_HAS_LOCATION (context)
+ ? EXPR_LOCUS (context)
+ : &DECL_SOURCE_LOCATION (var));
warning (msgid, locus, var);
TREE_NO_WARNING (var) = 1;
}
static tree
warn_uninitialized_var (tree *tp, int *walk_subtrees, void *data)
{
- location_t *locus = data;
tree t = *tp;
/* We only do data flow with SSA_NAMEs, so that's all we can warn about. */
if (TREE_CODE (t) == SSA_NAME)
{
- warn_uninit (t, "%H%qD is used uninitialized in this function", locus);
+ warn_uninit (t, "%H%qD is used uninitialized in this function", data);
*walk_subtrees = 0;
}
else if (IS_TYPE_OR_DECL_P (t))
FOR_EACH_BB (bb)
for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi))
- walk_tree (bsi_stmt_ptr (bsi), warn_uninitialized_var,
- EXPR_LOCUS (bsi_stmt (bsi)), NULL);
+ {
+ tree context = bsi_stmt (bsi);
+ walk_tree (bsi_stmt_ptr (bsi), warn_uninitialized_var,
+ context, NULL);
+ }
}
static void