/* Miscellaneous SSA utility functions.
- Copyright (C) 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
+ Copyright (C) 2001, 2002, 2003, 2004, 2005, 2007, 2008 Free Software
+ Foundation, Inc.
This file is part of GCC.
GCC is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
-the Free Software Foundation; either version 2, or (at your option)
+the Free Software Foundation; either version 3, or (at your option)
any later version.
GCC is distributed in the hope that it will be useful,
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
-along with GCC; see the file COPYING. If not, write to
-the Free Software Foundation, 51 Franklin Street, Fifth Floor,
-Boston, MA 02110-1301, USA. */
+along with GCC; see the file COPYING3. If not see
+<http://www.gnu.org/licenses/>. */
#include "config.h"
#include "system.h"
#include "bitmap.h"
#include "pointer-set.h"
#include "tree-flow.h"
-#include "tree-gimple.h"
+#include "gimple.h"
#include "tree-inline.h"
#include "varray.h"
#include "timevar.h"
#include "tree-pass.h"
#include "toplev.h"
+/* Pointer map of variable mappings, keyed by edge. */
+static struct pointer_map_t *edge_var_maps;
+
+
+/* Add a mapping with PHI RESULT and PHI DEF associated with edge E. */
+
+void
+redirect_edge_var_map_add (edge e, tree result, tree def)
+{
+ void **slot;
+ edge_var_map_vector old_head, head;
+ edge_var_map new_node;
+
+ if (edge_var_maps == NULL)
+ edge_var_maps = pointer_map_create ();
+
+ slot = pointer_map_insert (edge_var_maps, e);
+ old_head = head = (edge_var_map_vector) *slot;
+ if (!head)
+ {
+ head = VEC_alloc (edge_var_map, heap, 5);
+ *slot = head;
+ }
+ new_node.def = def;
+ new_node.result = result;
+
+ VEC_safe_push (edge_var_map, heap, head, &new_node);
+ if (old_head != head)
+ {
+ /* The push did some reallocation. Update the pointer map. */
+ *slot = head;
+ }
+}
+
+
+/* Clear the var mappings in edge E. */
+
+void
+redirect_edge_var_map_clear (edge e)
+{
+ void **slot;
+ edge_var_map_vector head;
+
+ if (!edge_var_maps)
+ return;
+
+ slot = pointer_map_contains (edge_var_maps, e);
+
+ if (slot)
+ {
+ head = (edge_var_map_vector) *slot;
+ VEC_free (edge_var_map, heap, head);
+ *slot = NULL;
+ }
+}
+
+
+/* Duplicate the redirected var mappings in OLDE in NEWE.
+
+ Since we can't remove a mapping, let's just duplicate it. This assumes a
+ pointer_map can have multiple edges mapping to the same var_map (many to
+ one mapping), since we don't remove the previous mappings. */
+
+void
+redirect_edge_var_map_dup (edge newe, edge olde)
+{
+ void **new_slot, **old_slot;
+ edge_var_map_vector head;
+
+ if (!edge_var_maps)
+ return;
+
+ new_slot = pointer_map_insert (edge_var_maps, newe);
+ old_slot = pointer_map_contains (edge_var_maps, olde);
+ if (!old_slot)
+ return;
+ head = (edge_var_map_vector) *old_slot;
+
+ if (head)
+ *new_slot = VEC_copy (edge_var_map, heap, head);
+ else
+ *new_slot = VEC_alloc (edge_var_map, heap, 5);
+}
+
+
+/* Return the variable mappings for a given edge. If there is none, return
+ NULL. */
+
+edge_var_map_vector
+redirect_edge_var_map_vector (edge e)
+{
+ void **slot;
+
+ /* Hey, what kind of idiot would... you'd be surprised. */
+ if (!edge_var_maps)
+ return NULL;
+
+ slot = pointer_map_contains (edge_var_maps, e);
+ if (!slot)
+ return NULL;
+
+ return (edge_var_map_vector) *slot;
+}
+
+/* Used by redirect_edge_var_map_destroy to free all memory. */
+
+static bool
+free_var_map_entry (const void *key ATTRIBUTE_UNUSED,
+ void **value,
+ void *data ATTRIBUTE_UNUSED)
+{
+ edge_var_map_vector head = (edge_var_map_vector) *value;
+ VEC_free (edge_var_map, heap, head);
+ return true;
+}
+
+/* Clear the edge variable mappings. */
+
+void
+redirect_edge_var_map_destroy (void)
+{
+ if (edge_var_maps)
+ {
+ pointer_map_traverse (edge_var_maps, free_var_map_entry, NULL);
+ pointer_map_destroy (edge_var_maps);
+ edge_var_maps = NULL;
+ }
+}
+
+
/* Remove the corresponding arguments from the PHI nodes in E's
destination block and redirect it to DEST. Return redirected edge.
- The list of removed arguments is stored in PENDING_STMT (e). */
+ The list of removed arguments is stored in a vector accessed
+ through edge_var_maps. */
edge
ssa_redirect_edge (edge e, basic_block dest)
{
- tree phi;
- tree list = NULL, *last = &list;
- tree src, dst, node;
+ gimple_stmt_iterator gsi;
+ gimple phi;
+
+ redirect_edge_var_map_clear (e);
/* Remove the appropriate PHI arguments in E's destination block. */
- for (phi = phi_nodes (e->dest); phi; phi = PHI_CHAIN (phi))
+ for (gsi = gsi_start_phis (e->dest); !gsi_end_p (gsi); gsi_next (&gsi))
{
- if (PHI_ARG_DEF (phi, e->dest_idx) == NULL_TREE)
+ tree def;
+
+ phi = gsi_stmt (gsi);
+ def = gimple_phi_arg_def (phi, e->dest_idx);
+
+ if (def == NULL_TREE)
continue;
- src = PHI_ARG_DEF (phi, e->dest_idx);
- dst = PHI_RESULT (phi);
- node = build_tree_list (dst, src);
- *last = node;
- last = &TREE_CHAIN (node);
+ redirect_edge_var_map_add (e, gimple_phi_result (phi), def);
}
e = redirect_edge_succ_nodup (e, dest);
- PENDING_STMT (e) = list;
return e;
}
+
/* Add PHI arguments queued in PENDING_STMT list on edge E to edge
E->dest. */
void
flush_pending_stmts (edge e)
{
- tree phi, arg;
-
- if (!PENDING_STMT (e))
+ gimple phi;
+ edge_var_map_vector v;
+ edge_var_map *vm;
+ int i;
+ gimple_stmt_iterator gsi;
+
+ v = redirect_edge_var_map_vector (e);
+ if (!v)
return;
- for (phi = phi_nodes (e->dest), arg = PENDING_STMT (e);
- phi;
- phi = PHI_CHAIN (phi), arg = TREE_CHAIN (arg))
+ for (gsi = gsi_start_phis (e->dest), i = 0;
+ !gsi_end_p (gsi) && VEC_iterate (edge_var_map, v, i, vm);
+ gsi_next (&gsi), i++)
{
- tree def = TREE_VALUE (arg);
+ tree def;
+
+ phi = gsi_stmt (gsi);
+ def = redirect_edge_var_map_def (vm);
add_phi_arg (phi, def, e);
}
- PENDING_STMT (e) = NULL;
+ redirect_edge_var_map_clear (e);
}
/* Return true if SSA_NAME is malformed and mark it visited.
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;
- }
-
if (SSA_NAME_IS_DEFAULT_DEF (ssa_name)
- && !IS_EMPTY_STMT (SSA_NAME_DEF_STMT (ssa_name)))
+ && !gimple_nop_p (SSA_NAME_DEF_STMT (ssa_name)))
{
error ("found a default name with a non-empty defining statement");
return true;
static bool
verify_def (basic_block bb, basic_block *definition_block, tree ssa_name,
- tree stmt, bool is_virtual)
+ gimple stmt, bool is_virtual)
{
if (verify_ssa_name (ssa_name, is_virtual))
goto err;
{
error ("SSA_NAME_DEF_STMT is wrong");
fprintf (stderr, "Expected definition statement:\n");
- print_generic_stmt (stderr, SSA_NAME_DEF_STMT (ssa_name), TDF_VOPS);
+ print_gimple_stmt (stderr, SSA_NAME_DEF_STMT (ssa_name), 4, TDF_VOPS);
fprintf (stderr, "\nActual definition statement:\n");
- print_generic_stmt (stderr, stmt, TDF_VOPS);
+ print_gimple_stmt (stderr, stmt, 4, TDF_VOPS);
goto err;
}
fprintf (stderr, "while verifying SSA_NAME ");
print_generic_expr (stderr, ssa_name, 0);
fprintf (stderr, " in statement\n");
- print_generic_stmt (stderr, stmt, TDF_VOPS);
+ print_gimple_stmt (stderr, stmt, 4, TDF_VOPS);
return true;
}
static bool
verify_use (basic_block bb, basic_block def_bb, use_operand_p use_p,
- tree stmt, bool check_abnormal, bitmap names_defined_in_bb)
+ gimple stmt, bool check_abnormal, bitmap names_defined_in_bb)
{
bool err = false;
tree ssa_name = USE_FROM_PTR (use_p);
TREE_VISITED (ssa_name) = 1;
- if (IS_EMPTY_STMT (SSA_NAME_DEF_STMT (ssa_name))
+ if (gimple_nop_p (SSA_NAME_DEF_STMT (ssa_name))
&& SSA_NAME_IS_DEFAULT_DEF (ssa_name))
; /* Default definitions have empty statements. Nothing to do. */
else if (!def_bb)
}
else
{
- tree listvar ;
+ tree listvar;
if (use_p->prev->use == NULL)
- listvar = use_p->prev->stmt;
+ listvar = use_p->prev->loc.ssa_name;
else
listvar = USE_FROM_PTR (use_p->prev);
if (listvar != ssa_name)
fprintf (stderr, "for SSA_NAME: ");
print_generic_expr (stderr, ssa_name, TDF_VOPS);
fprintf (stderr, " in statement:\n");
- print_generic_stmt (stderr, stmt, TDF_VOPS);
+ print_gimple_stmt (stderr, stmt, 0, TDF_VOPS);
}
return err;
definition of SSA_NAME. */
static bool
-verify_phi_args (tree phi, basic_block bb, basic_block *definition_block)
+verify_phi_args (gimple phi, basic_block bb, basic_block *definition_block)
{
edge e;
bool err = false;
- unsigned i, phi_num_args = PHI_NUM_ARGS (phi);
+ size_t i, phi_num_args = gimple_phi_num_args (phi);
if (EDGE_COUNT (bb->preds) != phi_num_args)
{
for (i = 0; i < phi_num_args; i++)
{
- use_operand_p op_p = PHI_ARG_DEF_PTR (phi, i);
+ use_operand_p op_p = gimple_phi_arg_imm_use_ptr (phi, i);
tree op = USE_FROM_PTR (op_p);
e = EDGE_PRED (bb, i);
if (TREE_CODE (op) == SSA_NAME)
{
- err = verify_ssa_name (op, !is_gimple_reg (PHI_RESULT (phi)));
+ err = verify_ssa_name (op, !is_gimple_reg (gimple_phi_result (phi)));
err |= verify_use (e->src, definition_block[SSA_NAME_VERSION (op)],
op_p, phi, e->flags & EDGE_ABNORMAL, NULL);
}
if (err)
{
fprintf (stderr, "for PHI node\n");
- print_generic_stmt (stderr, phi, TDF_VOPS|TDF_MEMSYMS);
+ print_gimple_stmt (stderr, phi, 0, TDF_VOPS|TDF_MEMSYMS);
}
continue;
ann = var_ann (var);
- if (pi->is_dereferenced && !pi->name_mem_tag && !ann->symbol_mem_tag)
+ if (pi->memory_tag_needed && !pi->name_mem_tag && !ann->symbol_mem_tag)
{
error ("dereferenced pointers should have a name or a symbol tag");
goto err;
goto err;
}
- if (pi->value_escapes_p && pi->name_mem_tag)
+ if (pi->value_escapes_p
+ && pi->escape_mask & ~ESCAPE_TO_RETURN
+ && pi->name_mem_tag)
{
tree t = memory_partition (pi->name_mem_tag);
if (t == NULL_TREE)
tree name = ssa_name (i);
if (name)
{
- tree stmt;
+ gimple stmt;
TREE_VISITED (name) = 0;
stmt = SSA_NAME_DEF_STMT (name);
- if (!IS_EMPTY_STMT (stmt))
+ if (!gimple_nop_p (stmt))
{
- basic_block bb = bb_for_stmt (stmt);
+ basic_block bb = gimple_bb (stmt);
verify_def (bb, definition_block,
name, stmt, !is_gimple_reg (name));
FOR_EACH_BB (bb)
{
edge e;
- tree phi;
+ gimple phi;
edge_iterator ei;
- block_stmt_iterator bsi;
+ gimple_stmt_iterator gsi;
/* Make sure that all edges have a clear 'aux' field. */
FOR_EACH_EDGE (e, ei, bb->preds)
}
/* Verify the arguments for every PHI node in the block. */
- for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
+ for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
{
+ phi = gsi_stmt (gsi);
if (verify_phi_args (phi, bb, definition_block))
goto err;
bitmap_set_bit (names_defined_in_bb,
- SSA_NAME_VERSION (PHI_RESULT (phi)));
+ SSA_NAME_VERSION (gimple_phi_result (phi)));
}
/* Now verify all the uses and vuses in every statement of the block. */
- for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi))
+ for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
{
- tree stmt = bsi_stmt (bsi);
+ gimple stmt = gsi_stmt (gsi);
use_operand_p use_p;
- if (check_modified_stmt && stmt_modified_p (stmt))
+ if (check_modified_stmt && gimple_modified_p (stmt))
{
error ("stmt (%p) marked modified after optimization pass: ",
(void *)stmt);
- print_generic_stmt (stderr, stmt, TDF_VOPS);
+ print_gimple_stmt (stderr, stmt, 0, TDF_VOPS);
goto err;
}
- if (TREE_CODE (stmt) == GIMPLE_MODIFY_STMT
- && TREE_CODE (GIMPLE_STMT_OPERAND (stmt, 0)) != SSA_NAME)
+ if (is_gimple_assign (stmt)
+ && TREE_CODE (gimple_assign_lhs (stmt)) != SSA_NAME)
{
tree lhs, base_address;
- lhs = GIMPLE_STMT_OPERAND (stmt, 0);
+ lhs = gimple_assign_lhs (stmt);
base_address = get_base_address (lhs);
if (base_address
&& gimple_aliases_computed_p (cfun)
&& SSA_VAR_P (base_address)
- && !stmt_ann (stmt)->has_volatile_ops
+ && !gimple_has_volatile_ops (stmt)
&& ZERO_SSA_OPERANDS (stmt, SSA_OP_VDEF))
{
error ("statement makes a memory store, but has no VDEFS");
- print_generic_stmt (stderr, stmt, TDF_VOPS);
+ print_gimple_stmt (stderr, stmt, 0, TDF_VOPS);
goto err;
}
}
if (verify_ssa_name (op, true))
{
error ("in statement");
- print_generic_stmt (stderr, stmt, TDF_VOPS|TDF_MEMSYMS);
+ print_gimple_stmt (stderr, stmt, 0, TDF_VOPS|TDF_MEMSYMS);
goto err;
}
}
if (verify_ssa_name (op, false))
{
error ("in statement");
- print_generic_stmt (stderr, stmt, TDF_VOPS|TDF_MEMSYMS);
+ print_gimple_stmt (stderr, stmt, 0, TDF_VOPS|TDF_MEMSYMS);
goto err;
}
}
return ((const struct int_tree_map *)item)->uid;
}
-/* Return true if the uid in both int tree maps are equal. */
+/* Return true if the DECL_UID in both trees are equal. */
+
+int
+uid_decl_map_eq (const void *va, const void *vb)
+{
+ const_tree a = (const_tree) va;
+ const_tree b = (const_tree) vb;
+ return (a->decl_minimal.uid == b->decl_minimal.uid);
+}
+
+/* Hash a tree in a uid_decl_map. */
+
+unsigned int
+uid_decl_map_hash (const void *item)
+{
+ return ((const_tree)item)->decl_minimal.uid;
+}
+
+/* Return true if the DECL_UID in both trees are equal. */
static int
-var_ann_eq (const void *va, const void *vb)
+uid_ssaname_map_eq (const void *va, const void *vb)
{
- const struct static_var_ann_d *a = (const struct static_var_ann_d *) va;
- tree b = (tree) vb;
- return (a->uid == DECL_UID (b));
+ const_tree a = (const_tree) va;
+ const_tree b = (const_tree) vb;
+ return (a->ssa_name.var->decl_minimal.uid == b->ssa_name.var->decl_minimal.uid);
}
-/* Hash a UID in a int_tree_map. */
+/* Hash a tree in a uid_decl_map. */
static unsigned int
-var_ann_hash (const void *item)
+uid_ssaname_map_hash (const void *item)
{
- return ((const struct static_var_ann_d *)item)->uid;
+ return ((const_tree)item)->ssa_name.var->decl_minimal.uid;
}
/* Initialize global DFA and SSA structures. */
void
-init_tree_ssa (void)
+init_tree_ssa (struct function *fn)
{
- cfun->gimple_df = GGC_CNEW (struct gimple_df);
- cfun->gimple_df->referenced_vars = htab_create_ggc (20, int_tree_map_hash,
- int_tree_map_eq, NULL);
- cfun->gimple_df->default_defs = htab_create_ggc (20, int_tree_map_hash,
- int_tree_map_eq, NULL);
- cfun->gimple_df->var_anns = htab_create_ggc (20, var_ann_hash,
- var_ann_eq, NULL);
- cfun->gimple_df->call_clobbered_vars = BITMAP_GGC_ALLOC ();
- cfun->gimple_df->addressable_vars = BITMAP_GGC_ALLOC ();
- init_ssanames ();
+ fn->gimple_df = GGC_CNEW (struct gimple_df);
+ fn->gimple_df->referenced_vars = htab_create_ggc (20, uid_decl_map_hash,
+ uid_decl_map_eq, NULL);
+ fn->gimple_df->default_defs = htab_create_ggc (20, uid_ssaname_map_hash,
+ uid_ssaname_map_eq, NULL);
+ fn->gimple_df->call_clobbered_vars = BITMAP_GGC_ALLOC ();
+ fn->gimple_df->call_used_vars = BITMAP_GGC_ALLOC ();
+ fn->gimple_df->addressable_vars = BITMAP_GGC_ALLOC ();
+ init_ssanames (fn, 0);
init_phinodes ();
}
{
size_t i;
basic_block bb;
- block_stmt_iterator bsi;
+ gimple_stmt_iterator gsi;
referenced_var_iterator rvi;
tree var;
release_ssa_name (var);
}
- /* Remove annotations from every tree in the function. */
+ /* FIXME. This may not be necessary. We will release all this
+ memory en masse in free_ssa_operands. This clearing used to be
+ necessary to avoid problems with the inliner, but it may not be
+ needed anymore. */
FOR_EACH_BB (bb)
{
- for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi))
+ for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
{
- tree stmt = bsi_stmt (bsi);
- stmt_ann_t ann = get_stmt_ann (stmt);
+ gimple stmt = gsi_stmt (gsi);
- free_ssa_operands (&ann->operands);
- ann->addresses_taken = 0;
- mark_stmt_modified (stmt);
+ if (gimple_has_ops (stmt))
+ {
+ gimple_set_def_ops (stmt, NULL);
+ gimple_set_use_ops (stmt, NULL);
+ gimple_set_addresses_taken (stmt, NULL);
+ }
+
+ if (gimple_has_mem_ops (stmt))
+ {
+ gimple_set_vdef_ops (stmt, NULL);
+ gimple_set_vuse_ops (stmt, NULL);
+ BITMAP_FREE (stmt->gsmem.membase.stores);
+ BITMAP_FREE (stmt->gsmem.membase.loads);
+ }
+
+ gimple_set_modified (stmt, true);
}
set_phi_nodes (bb, NULL);
}
- /* Remove annotations from every referenced variable. */
+ /* Remove annotations from every referenced local variable. */
FOR_EACH_REFERENCED_VAR (var, rvi)
{
+ if (!MTAG_P (var)
+ && (TREE_STATIC (var) || DECL_EXTERNAL (var)))
+ {
+ var_ann (var)->mpt = NULL_TREE;
+ var_ann (var)->symbol_mem_tag = NULL_TREE;
+ continue;
+ }
if (var->base.ann)
ggc_free (var->base.ann);
var->base.ann = NULL;
fini_ssanames ();
fini_phinodes ();
- /* we no longer maintain the SSA operand cache at this point. */
- fini_ssa_operands ();
+
+ /* We no longer maintain the SSA operand cache at this point. */
+ if (ssa_operands_active ())
+ fini_ssa_operands ();
cfun->gimple_df->global_var = NULL_TREE;
htab_delete (cfun->gimple_df->default_defs);
cfun->gimple_df->default_defs = NULL;
- htab_delete (cfun->gimple_df->var_anns);
- cfun->gimple_df->var_anns = NULL;
cfun->gimple_df->call_clobbered_vars = NULL;
+ cfun->gimple_df->call_used_vars = NULL;
cfun->gimple_df->addressable_vars = NULL;
cfun->gimple_df->modified_noreturn_calls = NULL;
if (gimple_aliases_computed_p (cfun))
delete_mem_ref_stats (cfun);
cfun->gimple_df = NULL;
-}
-
-/* Return true if the conversion from INNER_TYPE to OUTER_TYPE is a
- useless type conversion, otherwise return false.
-
- This function implicitly defines the middle-end type system. With
- the notion of 'a < b' meaning that useless_type_conversion_p (a, b)
- holds and 'a > b' meaning that useless_type_conversion_p (b, a) holds,
- the following invariants shall be fulfilled:
-
- 1) useless_type_conversion_p is transitive.
- If a < b and b < c then a < c.
-
- 2) useless_type_conversion_p is not symmetric.
- From a < b does not follow a > b.
+ /* We no longer need the edge variable maps. */
+ redirect_edge_var_map_destroy ();
+}
- 3) Types define the available set of operations applicable to values.
- A type conversion is useless if the operations for the target type
- is a subset of the operations for the source type. For example
- casts to void* are useless, casts from void* are not (void* can't
- be dereferenced or offsetted, but copied, hence its set of operations
- is a strict subset of that of all other data pointer types). Casts
- to const T* are useless (can't be written to), casts from const T*
- to T* are not. */
+/* Helper function for useless_type_conversion_p. */
-bool
-useless_type_conversion_p (tree outer_type, tree inner_type)
+static bool
+useless_type_conversion_p_1 (tree outer_type, tree inner_type)
{
/* Qualifiers on value types do not matter. */
inner_type = TYPE_MAIN_VARIANT (inner_type);
|| TYPE_PRECISION (inner_type) != TYPE_PRECISION (outer_type))
return false;
- /* Preserve booleanness. Some code assumes an invariant that boolean
- types stay boolean and do not become 1-bit bit-field types. */
- if ((TREE_CODE (inner_type) == BOOLEAN_TYPE)
- != (TREE_CODE (outer_type) == BOOLEAN_TYPE))
+ /* Conversions from a non-base to a base type are not useless.
+ This way we preserve the invariant to do arithmetic in
+ base types only. */
+ if (TREE_TYPE (inner_type)
+ && TREE_TYPE (inner_type) != inner_type
+ && (TREE_TYPE (outer_type) == outer_type
+ || TREE_TYPE (outer_type) == NULL_TREE))
return false;
- /* Preserve changes in the types minimum or maximum value.
- ??? Due to the way we handle sizetype as signed we need
- to jump through hoops here to make sizetype and size_type_node
- compatible. */
- if (!tree_int_cst_equal (fold_convert (outer_type,
- TYPE_MIN_VALUE (inner_type)),
- TYPE_MIN_VALUE (outer_type))
- || !tree_int_cst_equal (fold_convert (outer_type,
- TYPE_MAX_VALUE (inner_type)),
- TYPE_MAX_VALUE (outer_type)))
- return false;
+ /* We don't need to preserve changes in the types minimum or
+ maximum value in general as these do not generate code
+ unless the types precisions are different. */
return true;
}
else if (POINTER_TYPE_P (inner_type)
&& POINTER_TYPE_P (outer_type))
{
- /* If the outer type is (void *), then the conversion is not
- necessary. */
- if (TREE_CODE (TREE_TYPE (outer_type)) == VOID_TYPE)
- return true;
-
/* Don't lose casts between pointers to volatile and non-volatile
qualified types. Doing so would result in changing the semantics
of later accesses. */
!= get_alias_set (TREE_TYPE (outer_type))))
return false;
- /* Do not lose casts from const qualified to non-const
- qualified. */
- if ((TYPE_READONLY (TREE_TYPE (outer_type))
- != TYPE_READONLY (TREE_TYPE (inner_type)))
- && TYPE_READONLY (TREE_TYPE (inner_type)))
- return false;
+ /* We do not care for const qualification of the pointed-to types
+ as const qualification has no semantic value to the middle-end. */
/* Do not lose casts to restrict qualified pointers. */
if ((TYPE_RESTRICT (outer_type)
to types are effectively the same. We can strip qualifiers
on pointed-to types for further comparison, which is done in
the callee. */
- return useless_type_conversion_p (TREE_TYPE (outer_type),
- TREE_TYPE (inner_type));
+ return useless_type_conversion_p_1 (TREE_TYPE (outer_type),
+ TREE_TYPE (inner_type));
}
/* Recurse for complex types. */
if (TREE_CODE (inner_type) != TREE_CODE (outer_type))
return false;
- /* ??? Add structural equivalence check. */
+ /* ??? This seems to be necessary even for aggregates that don't
+ have TYPE_STRUCTURAL_EQUALITY_P set. */
/* ??? This should eventually just return false. */
return lang_hooks.types_compatible_p (inner_type, outer_type);
}
-
+ /* Also for functions and possibly other types with
+ TYPE_STRUCTURAL_EQUALITY_P set. */
+ else if (TYPE_STRUCTURAL_EQUALITY_P (inner_type)
+ && TYPE_STRUCTURAL_EQUALITY_P (outer_type))
+ return lang_hooks.types_compatible_p (inner_type, outer_type);
+
return false;
}
+/* Return true if the conversion from INNER_TYPE to OUTER_TYPE is a
+ useless type conversion, otherwise return false.
+
+ This function implicitly defines the middle-end type system. With
+ the notion of 'a < b' meaning that useless_type_conversion_p (a, b)
+ holds and 'a > b' meaning that useless_type_conversion_p (b, a) holds,
+ the following invariants shall be fulfilled:
+
+ 1) useless_type_conversion_p is transitive.
+ If a < b and b < c then a < c.
+
+ 2) useless_type_conversion_p is not symmetric.
+ From a < b does not follow a > b.
+
+ 3) Types define the available set of operations applicable to values.
+ A type conversion is useless if the operations for the target type
+ is a subset of the operations for the source type. For example
+ casts to void* are useless, casts from void* are not (void* can't
+ be dereferenced or offsetted, but copied, hence its set of operations
+ is a strict subset of that of all other data pointer types). Casts
+ to const T* are useless (can't be written to), casts from const T*
+ to T* are not. */
+
+bool
+useless_type_conversion_p (tree outer_type, tree inner_type)
+{
+ /* If the outer type is (void *), then the conversion is not
+ necessary. We have to make sure to not apply this while
+ recursing though. */
+ if (POINTER_TYPE_P (inner_type)
+ && POINTER_TYPE_P (outer_type)
+ && TREE_CODE (TREE_TYPE (outer_type)) == VOID_TYPE)
+ return true;
+
+ return useless_type_conversion_p_1 (outer_type, inner_type);
+}
+
/* Return true if a conversion from either type of TYPE1 and TYPE2
to the other is not required. Otherwise return false. */
the top of the RHS to the type of the LHS and the type conversion
is "safe", then strip away the type conversion so that we can
enter LHS = RHS into the const_and_copies table. */
- if (TREE_CODE (expr) == NOP_EXPR || TREE_CODE (expr) == CONVERT_EXPR
+ if (CONVERT_EXPR_P (expr)
|| TREE_CODE (expr) == VIEW_CONVERT_EXPR
|| TREE_CODE (expr) == NON_LVALUE_EXPR)
- /* FIXME: Use of GENERIC_TREE_TYPE here is a temporary measure to work
- around known bugs with GIMPLE_MODIFY_STMTs appearing in places
- they shouldn't. See PR 30391. */
return useless_type_conversion_p
(TREE_TYPE (expr),
- GENERIC_TREE_TYPE (TREE_OPERAND (expr, 0)));
+ TREE_TYPE (TREE_OPERAND (expr, 0)));
return false;
}
walk_use_def_chains_1 (tree var, walk_use_def_chains_fn fn, void *data,
struct pointer_set_t *visited, bool is_dfs)
{
- tree def_stmt;
+ gimple def_stmt;
if (pointer_set_insert (visited, var))
return false;
def_stmt = SSA_NAME_DEF_STMT (var);
- if (TREE_CODE (def_stmt) != PHI_NODE)
+ if (gimple_code (def_stmt) != GIMPLE_PHI)
{
/* If we reached the end of the use-def chain, call FN. */
return fn (var, def_stmt, data);
}
else
{
- int i;
+ size_t i;
/* When doing a breadth-first search, call FN before following the
use-def links for each argument. */
if (!is_dfs)
- for (i = 0; i < PHI_NUM_ARGS (def_stmt); i++)
- if (fn (PHI_ARG_DEF (def_stmt, i), def_stmt, data))
+ for (i = 0; i < gimple_phi_num_args (def_stmt); i++)
+ if (fn (gimple_phi_arg_def (def_stmt, i), def_stmt, data))
return true;
/* Follow use-def links out of each PHI argument. */
- for (i = 0; i < PHI_NUM_ARGS (def_stmt); i++)
+ for (i = 0; i < gimple_phi_num_args (def_stmt); i++)
{
- tree arg = PHI_ARG_DEF (def_stmt, i);
+ tree arg = gimple_phi_arg_def (def_stmt, i);
/* ARG may be NULL for newly introduced PHI nodes. */
if (arg
/* When doing a depth-first search, call FN after following the
use-def links for each argument. */
if (is_dfs)
- for (i = 0; i < PHI_NUM_ARGS (def_stmt); i++)
- if (fn (PHI_ARG_DEF (def_stmt, i), def_stmt, data))
+ for (i = 0; i < gimple_phi_num_args (def_stmt); i++)
+ if (fn (gimple_phi_arg_def (def_stmt, i), def_stmt, data))
return true;
}
walk_use_def_chains (tree var, walk_use_def_chains_fn fn, void *data,
bool is_dfs)
{
- tree def_stmt;
+ gimple def_stmt;
gcc_assert (TREE_CODE (var) == SSA_NAME);
/* We only need to recurse if the reaching definition comes from a PHI
node. */
- if (TREE_CODE (def_stmt) != PHI_NODE)
+ if (gimple_code (def_stmt) != GIMPLE_PHI)
(*fn) (var, def_stmt, data);
else
{
}
\f
+/* Return true if T, an SSA_NAME, has an undefined value. */
+
+bool
+ssa_undefined_value_p (tree t)
+{
+ tree var = SSA_NAME_VAR (t);
+
+ /* Parameters get their initial value from the function entry. */
+ if (TREE_CODE (var) == PARM_DECL)
+ return false;
+
+ /* Hard register variables get their initial value from the ether. */
+ if (TREE_CODE (var) == VAR_DECL && DECL_HARD_REGISTER (var))
+ return false;
+
+ /* The value is undefined iff its definition statement is empty. */
+ return gimple_nop_p (SSA_NAME_DEF_STMT (t));
+}
+
/* Emit warnings for uninitialized variables. This is done in two passes.
- The first pass notices real uses of SSA names with default definitions.
+ The first pass notices real uses of SSA names with undefined values.
Such uses are unconditionally uninitialized, and we can be certain that
such a use is a mistake. This pass is run before most optimizations,
so that we catch as many as we can.
warn_uninit (tree t, const char *gmsgid, void *data)
{
tree var = SSA_NAME_VAR (t);
- tree def = SSA_NAME_DEF_STMT (t);
- tree context = (tree) data;
- location_t *locus;
+ gimple context = (gimple) data;
+ location_t location;
expanded_location xloc, floc;
- /* Default uses (indicated by an empty definition statement),
- are uninitialized. */
- if (!IS_EMPTY_STMT (def))
- return;
-
- /* Except for PARMs of course, which are always initialized. */
- if (TREE_CODE (var) == PARM_DECL)
- return;
-
- /* Hard register variables get their initial value from the ether. */
- if (TREE_CODE (var) == VAR_DECL && DECL_HARD_REGISTER (var))
+ if (!ssa_undefined_value_p (t))
return;
/* TREE_NO_WARNING either means we already warned, or the front end
if (TREE_NO_WARNING (var))
return;
- locus = (context != NULL && EXPR_HAS_LOCATION (context)
- ? EXPR_LOCUS (context)
- : &DECL_SOURCE_LOCATION (var));
- warning (OPT_Wuninitialized, gmsgid, locus, var);
- xloc = expand_location (*locus);
+ /* Do not warn if it can be initialized outside this module. */
+ if (is_global_var (var))
+ return;
+
+ location = (context != NULL && gimple_has_location (context))
+ ? gimple_location (context)
+ : DECL_SOURCE_LOCATION (var);
+ xloc = expand_location (location);
floc = expand_location (DECL_SOURCE_LOCATION (cfun->decl));
- if (xloc.file != floc.file
- || xloc.line < floc.line
- || xloc.line > LOCATION_LINE (cfun->function_end_locus))
- inform ("%J%qD was declared here", var, var);
+ if (warning_at (location, OPT_Wuninitialized, gmsgid, var))
+ {
+ TREE_NO_WARNING (var) = 1;
- TREE_NO_WARNING (var) = 1;
+ if (xloc.file != floc.file
+ || xloc.line < floc.line
+ || xloc.line > LOCATION_LINE (cfun->function_end_locus))
+ inform (input_location, "%J%qD was declared here", var, var);
+ }
}
-
+
+struct walk_data {
+ gimple stmt;
+ bool always_executed;
+ bool warn_possibly_uninitialized;
+};
+
/* Called via walk_tree, look for SSA_NAMEs that have empty definitions
and warn about them. */
static tree
-warn_uninitialized_var (tree *tp, int *walk_subtrees, void *data)
+warn_uninitialized_var (tree *tp, int *walk_subtrees, void *data_)
{
+ struct walk_stmt_info *wi = (struct walk_stmt_info *) data_;
+ struct walk_data *data = (struct walk_data *) wi->info;
tree t = *tp;
+ /* We do not care about LHS. */
+ if (wi->is_lhs)
+ return NULL_TREE;
+
switch (TREE_CODE (t))
{
+ case ADDR_EXPR:
+ /* Taking the address of an uninitialized variable does not
+ count as using it. */
+ *walk_subtrees = 0;
+ break;
+
+ case VAR_DECL:
+ {
+ /* A VAR_DECL in the RHS of a gimple statement may mean that
+ this variable is loaded from memory. */
+ use_operand_p vuse;
+ tree op;
+
+ /* If there is not gimple stmt,
+ or alias information has not been computed,
+ then we cannot check VUSE ops. */
+ if (data->stmt == NULL
+ || !gimple_aliases_computed_p (cfun))
+ return NULL_TREE;
+
+ vuse = SINGLE_SSA_USE_OPERAND (data->stmt, SSA_OP_VUSE);
+ if (vuse == NULL_USE_OPERAND_P)
+ return NULL_TREE;
+
+ op = USE_FROM_PTR (vuse);
+ if (t != SSA_NAME_VAR (op)
+ || !SSA_NAME_IS_DEFAULT_DEF (op))
+ return NULL_TREE;
+ /* If this is a VUSE of t and it is the default definition,
+ then warn about op. */
+ t = op;
+ /* Fall through into SSA_NAME. */
+ }
+
case SSA_NAME:
/* We only do data flow with SSA_NAMEs, so that's all we
can warn about. */
- warn_uninit (t, "%H%qD is used uninitialized in this function", data);
+ if (data->always_executed)
+ warn_uninit (t, "%qD is used uninitialized in this function",
+ data->stmt);
+ else if (data->warn_possibly_uninitialized)
+ warn_uninit (t, "%qD may be used uninitialized in this function",
+ data->stmt);
*walk_subtrees = 0;
break;
and warn about them. */
static void
-warn_uninitialized_phi (tree phi)
+warn_uninitialized_phi (gimple phi)
{
- int i, n = PHI_NUM_ARGS (phi);
+ size_t i, n = gimple_phi_num_args (phi);
/* Don't look at memory tags. */
- if (!is_gimple_reg (PHI_RESULT (phi)))
+ if (!is_gimple_reg (gimple_phi_result (phi)))
return;
for (i = 0; i < n; ++i)
{
- tree op = PHI_ARG_DEF (phi, i);
+ tree op = gimple_phi_arg_def (phi, i);
if (TREE_CODE (op) == SSA_NAME)
- warn_uninit (op, "%H%qD may be used uninitialized in this function",
+ warn_uninit (op, "%qD may be used uninitialized in this function",
NULL);
}
}
static unsigned int
-execute_early_warn_uninitialized (void)
+warn_uninitialized_vars (bool warn_possibly_uninitialized)
{
- block_stmt_iterator bsi;
+ gimple_stmt_iterator gsi;
basic_block bb;
+ struct walk_data data;
+
+ data.warn_possibly_uninitialized = warn_possibly_uninitialized;
+
+ calculate_dominance_info (CDI_POST_DOMINATORS);
FOR_EACH_BB (bb)
- for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi))
- {
- tree context = bsi_stmt (bsi);
- walk_tree (bsi_stmt_ptr (bsi), warn_uninitialized_var,
- context, NULL);
- }
+ {
+ data.always_executed = dominated_by_p (CDI_POST_DOMINATORS,
+ single_succ (ENTRY_BLOCK_PTR), bb);
+ for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+ {
+ struct walk_stmt_info wi;
+ data.stmt = gsi_stmt (gsi);
+ memset (&wi, 0, sizeof (wi));
+ wi.info = &data;
+ walk_gimple_op (gsi_stmt (gsi), warn_uninitialized_var, &wi);
+ }
+ }
+ return 0;
+}
+
+static unsigned int
+execute_early_warn_uninitialized (void)
+{
+ /* Currently, this pass runs always but
+ execute_late_warn_uninitialized only runs with optimization. With
+ optimization we want to warn about possible uninitialized as late
+ as possible, thus don't do it here. However, without
+ optimization we need to warn here about "may be uninitialized".
+ */
+ warn_uninitialized_vars (/*warn_possibly_uninitialized=*/!optimize);
return 0;
}
execute_late_warn_uninitialized (void)
{
basic_block bb;
- tree phi;
+ gimple_stmt_iterator gsi;
/* Re-do the plain uninitialized variable check, as optimization may have
straightened control flow. Do this first so that we don't accidentally
get a "may be" warning when we'd have seen an "is" warning later. */
- execute_early_warn_uninitialized ();
+ warn_uninitialized_vars (/*warn_possibly_uninitialized=*/1);
FOR_EACH_BB (bb)
- for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
- warn_uninitialized_phi (phi);
+ for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+ warn_uninitialized_phi (gsi_stmt (gsi));
+
return 0;
}
return warn_uninitialized != 0;
}
-struct tree_opt_pass pass_early_warn_uninitialized =
+struct gimple_opt_pass pass_early_warn_uninitialized =
{
+ {
+ GIMPLE_PASS,
NULL, /* name */
gate_warn_uninitialized, /* gate */
execute_early_warn_uninitialized, /* execute */
0, /* properties_provided */
0, /* properties_destroyed */
0, /* todo_flags_start */
- 0, /* todo_flags_finish */
- 0 /* letter */
+ 0 /* todo_flags_finish */
+ }
};
-struct tree_opt_pass pass_late_warn_uninitialized =
+struct gimple_opt_pass pass_late_warn_uninitialized =
{
+ {
+ GIMPLE_PASS,
NULL, /* name */
gate_warn_uninitialized, /* gate */
execute_late_warn_uninitialized, /* execute */
0, /* properties_provided */
0, /* properties_destroyed */
0, /* todo_flags_start */
- 0, /* todo_flags_finish */
- 0 /* letter */
+ 0 /* todo_flags_finish */
+ }
+};
+
+/* Compute TREE_ADDRESSABLE and DECL_GIMPLE_REG_P for local variables. */
+
+static unsigned int
+execute_update_addresses_taken (void)
+{
+ tree var;
+ referenced_var_iterator rvi;
+ gimple_stmt_iterator gsi;
+ basic_block bb;
+ bitmap addresses_taken = BITMAP_ALLOC (NULL);
+ bitmap not_reg_needs = BITMAP_ALLOC (NULL);
+ bitmap vars_updated = BITMAP_ALLOC (NULL);
+ bool update_vops = false;
+
+ /* Collect into ADDRESSES_TAKEN all variables whose address is taken within
+ the function body. */
+ FOR_EACH_BB (bb)
+ {
+ for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+ {
+ const_gimple stmt = gsi_stmt (gsi);
+ enum gimple_code code = gimple_code (stmt);
+ bitmap taken = gimple_addresses_taken (stmt);
+
+ if (taken)
+ bitmap_ior_into (addresses_taken, taken);
+
+ /* If we have a call or an assignment, see if the lhs contains
+ a local decl that requires not to be a gimple register. */
+ if (code == GIMPLE_ASSIGN || code == GIMPLE_CALL)
+ {
+ tree lhs = gimple_get_lhs (stmt);
+ /* A plain decl does not need it set. */
+ if (lhs && handled_component_p (lhs))
+ {
+ var = get_base_address (lhs);
+ if (DECL_P (var))
+ bitmap_set_bit (not_reg_needs, DECL_UID (var));
+ }
+ }
+ }
+
+ for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+ {
+ size_t i;
+ gimple phi = gsi_stmt (gsi);
+
+ for (i = 0; i < gimple_phi_num_args (phi); i++)
+ {
+ tree op = PHI_ARG_DEF (phi, i), var;
+ if (TREE_CODE (op) == ADDR_EXPR
+ && (var = get_base_address (TREE_OPERAND (op, 0))) != NULL
+ && DECL_P (var))
+ bitmap_set_bit (addresses_taken, DECL_UID (var));
+ }
+ }
+ }
+
+ /* When possible, clear ADDRESSABLE bit or set the REGISTER bit
+ and mark variable for conversion into SSA. */
+ FOR_EACH_REFERENCED_VAR (var, rvi)
+ {
+ /* Global Variables, result decls cannot be changed. */
+ if (is_global_var (var)
+ || TREE_CODE (var) == RESULT_DECL
+ || bitmap_bit_p (addresses_taken, DECL_UID (var)))
+ continue;
+
+ if (TREE_ADDRESSABLE (var))
+ {
+ TREE_ADDRESSABLE (var) = 0;
+ if (is_gimple_reg (var))
+ mark_sym_for_renaming (var);
+ update_vops = true;
+ bitmap_set_bit (vars_updated, DECL_UID (var));
+ if (dump_file)
+ {
+ fprintf (dump_file, "No longer having address taken ");
+ print_generic_expr (dump_file, var, 0);
+ fprintf (dump_file, "\n");
+ }
+ }
+ if (!DECL_GIMPLE_REG_P (var)
+ && !bitmap_bit_p (not_reg_needs, DECL_UID (var))
+ && (TREE_CODE (TREE_TYPE (var)) == COMPLEX_TYPE
+ || TREE_CODE (TREE_TYPE (var)) == VECTOR_TYPE))
+ {
+ DECL_GIMPLE_REG_P (var) = 1;
+ mark_sym_for_renaming (var);
+ update_vops = true;
+ bitmap_set_bit (vars_updated, DECL_UID (var));
+ if (dump_file)
+ {
+ fprintf (dump_file, "Decl is now a gimple register ");
+ print_generic_expr (dump_file, var, 0);
+ fprintf (dump_file, "\n");
+ }
+ }
+ }
+
+ /* Operand caches needs to be recomputed for operands referencing the updated
+ variables. */
+ if (update_vops)
+ FOR_EACH_BB (bb)
+ for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+ {
+ gimple stmt = gsi_stmt (gsi);
+
+ if ((gimple_loaded_syms (stmt)
+ && bitmap_intersect_p (gimple_loaded_syms (stmt), vars_updated))
+ || (gimple_stored_syms (stmt)
+ && bitmap_intersect_p (gimple_stored_syms (stmt), vars_updated)))
+ update_stmt (stmt);
+ }
+ BITMAP_FREE (not_reg_needs);
+ BITMAP_FREE (addresses_taken);
+ BITMAP_FREE (vars_updated);
+ return 0;
+}
+
+struct gimple_opt_pass pass_update_address_taken =
+{
+ {
+ GIMPLE_PASS,
+ "addressables", /* name */
+ NULL, /* gate */
+ execute_update_addresses_taken, /* execute */
+ NULL, /* sub */
+ NULL, /* next */
+ 0, /* static_pass_number */
+ 0, /* tv_id */
+ PROP_ssa, /* properties_required */
+ 0, /* properties_provided */
+ 0, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ TODO_update_ssa /* todo_flags_finish */
+ }
};