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, 59 Temple Place - Suite 330,
-Boston, MA 02111-1307, USA. */
+the Free Software Foundation, 51 Franklin Street, Fifth Floor,
+Boston, MA 02110-1301, USA. */
#include "config.h"
#include "system.h"
#include "hard-reg-set.h"
#include "basic-block.h"
#include "output.h"
-#include "errors.h"
#include "timevar.h"
#include "expr.h"
#include "ggc.h"
long num_phis;
long num_phi_args;
int max_num_phi_args;
- long num_v_may_defs;
+ long num_vdefs;
long num_vuses;
- long num_v_must_defs;
-};
-
-
-/* State information for find_vars_r. */
-struct walk_state
-{
- /* Hash table used to avoid adding the same variable more than once. */
- htab_t vars_found;
};
static void collect_dfa_stats (struct dfa_stats_d *);
static tree collect_dfa_stats_r (tree *, int *, void *);
static tree find_vars_r (tree *, int *, void *);
-static void add_referenced_var (tree, struct walk_state *);
-
-
-/* Global declarations. */
-
-/* Array of all variables referenced in the function. */
-varray_type referenced_vars;
/*---------------------------------------------------------------------------
various attributes for each variable used by alias analysis and the
optimizer. */
-static void
+static unsigned int
find_referenced_vars (void)
{
- htab_t vars_found;
basic_block bb;
block_stmt_iterator si;
- struct walk_state walk_state;
-
- vars_found = htab_create (50, htab_hash_pointer, htab_eq_pointer, NULL);
- memset (&walk_state, 0, sizeof (walk_state));
- walk_state.vars_found = vars_found;
FOR_EACH_BB (bb)
for (si = bsi_start (bb); !bsi_end_p (si); bsi_next (&si))
{
tree *stmt_p = bsi_stmt_ptr (si);
- walk_tree (stmt_p, find_vars_r, &walk_state, NULL);
+ walk_tree (stmt_p, find_vars_r, NULL, NULL);
}
- htab_delete (vars_found);
+ return 0;
}
struct tree_opt_pass pass_referenced_vars =
gcc_assert (t);
gcc_assert (DECL_P (t));
- gcc_assert (!t->common.ann || t->common.ann->common.type == VAR_ANN);
+ gcc_assert (!t->base.ann || t->base.ann->common.type == VAR_ANN);
- ann = ggc_alloc (sizeof (*ann));
- memset ((void *) ann, 0, sizeof (*ann));
+ ann = GGC_CNEW (struct var_ann_d);
ann->common.type = VAR_ANN;
- t->common.ann = (tree_ann_t) ann;
+ t->base.ann = (tree_ann_t) ann;
return ann;
}
+/* Create a new annotation for a FUNCTION_DECL node T. */
+
+function_ann_t
+create_function_ann (tree t)
+{
+ function_ann_t ann;
+
+ gcc_assert (t);
+ gcc_assert (TREE_CODE (t) == FUNCTION_DECL);
+ gcc_assert (!t->base.ann || t->base.ann->common.type == FUNCTION_ANN);
+
+ ann = ggc_alloc (sizeof (*ann));
+ memset ((void *) ann, 0, sizeof (*ann));
+
+ ann->common.type = FUNCTION_ANN;
+
+ t->base.ann = (tree_ann_t) ann;
+
+ return ann;
+}
/* Create a new annotation for a statement node T. */
stmt_ann_t ann;
gcc_assert (is_gimple_stmt (t));
- gcc_assert (!t->common.ann || t->common.ann->common.type == STMT_ANN);
+ gcc_assert (!t->base.ann || t->base.ann->common.type == STMT_ANN);
- ann = ggc_alloc (sizeof (*ann));
- memset ((void *) ann, 0, sizeof (*ann));
+ ann = GGC_CNEW (struct stmt_ann_d);
ann->common.type = STMT_ANN;
/* Since we just created the annotation, mark the statement modified. */
ann->modified = true;
- t->common.ann = (tree_ann_t) ann;
+ t->base.ann = (tree_ann_t) ann;
return ann;
}
-
/* Create a new annotation for a tree T. */
-tree_ann_t
-create_tree_ann (tree t)
+tree_ann_common_t
+create_tree_common_ann (tree t)
{
- tree_ann_t ann;
+ tree_ann_common_t ann;
gcc_assert (t);
- gcc_assert (!t->common.ann || t->common.ann->common.type == TREE_ANN_COMMON);
+ gcc_assert (!t->base.ann || t->base.ann->common.type == TREE_ANN_COMMON);
- ann = ggc_alloc (sizeof (*ann));
- memset ((void *) ann, 0, sizeof (*ann));
+ ann = GGC_CNEW (struct tree_ann_common_d);
- ann->common.type = TREE_ANN_COMMON;
- t->common.ann = ann;
+ ann->type = TREE_ANN_COMMON;
+ t->base.ann = (tree_ann_t) ann;
return ann;
}
make_rename_temp (tree type, const char *prefix)
{
tree t = create_tmp_var (type, prefix);
- if (referenced_vars)
+
+ if (TREE_CODE (type) == COMPLEX_TYPE)
+ DECL_COMPLEX_GIMPLE_REG_P (t) = 1;
+
+ if (gimple_referenced_vars (cfun))
{
- add_referenced_tmp_var (t);
- bitmap_set_bit (vars_to_rename, var_ann (t)->uid);
+ add_referenced_var (t);
+ mark_sym_for_renaming (t);
}
+
return t;
}
void
dump_referenced_vars (FILE *file)
{
- size_t i;
-
+ tree var;
+ referenced_var_iterator rvi;
+
fprintf (file, "\nReferenced variables in %s: %u\n\n",
get_name (current_function_decl), (unsigned) num_referenced_vars);
-
- for (i = 0; i < num_referenced_vars; i++)
+
+ FOR_EACH_REFERENCED_VAR (var, rvi)
{
- tree var = referenced_var (i);
fprintf (file, "Variable: ");
dump_variable (file, var);
fprintf (file, "\n");
}
+/* Dump sub-variables for VAR to FILE. */
+
+void
+dump_subvars_for (FILE *file, tree var)
+{
+ subvar_t sv = get_subvars_for_var (var);
+
+ if (!sv)
+ return;
+
+ fprintf (file, "{ ");
+
+ for (; sv; sv = sv->next)
+ {
+ print_generic_expr (file, sv->var, dump_flags);
+ fprintf (file, " ");
+ }
+
+ fprintf (file, "}");
+}
+
+
+/* Dumb sub-variables for VAR to stderr. */
+
+void
+debug_subvars_for (tree var)
+{
+ dump_subvars_for (stderr, var);
+}
+
+
/* Dump variable VAR and its may-aliases to FILE. */
void
ann = var_ann (var);
- fprintf (file, ", UID %u", (unsigned) ann->uid);
+ fprintf (file, ", UID %u", (unsigned) DECL_UID (var));
fprintf (file, ", ");
print_generic_expr (file, TREE_TYPE (var), dump_flags);
- if (ann->type_mem_tag)
+ if (ann && ann->symbol_mem_tag)
{
- fprintf (file, ", type memory tag: ");
- print_generic_expr (file, ann->type_mem_tag, dump_flags);
+ fprintf (file, ", symbol memory tag: ");
+ print_generic_expr (file, ann->symbol_mem_tag, dump_flags);
}
- if (ann->is_alias_tag)
- fprintf (file, ", is an alias tag");
+ if (ann && ann->is_aliased)
+ fprintf (file, ", is aliased");
if (TREE_ADDRESSABLE (var))
fprintf (file, ", is addressable");
fprintf (file, ", is volatile");
if (is_call_clobbered (var))
- fprintf (file, ", call clobbered");
+ {
+ var_ann_t va = var_ann (var);
+ unsigned int escape_mask = va->escape_mask;
+
+ fprintf (file, ", call clobbered");
+ fprintf (file, " (");
+ if (escape_mask & ESCAPE_STORED_IN_GLOBAL)
+ fprintf (file, ", stored in global");
+ if (escape_mask & ESCAPE_TO_ASM)
+ fprintf (file, ", goes through ASM");
+ if (escape_mask & ESCAPE_TO_CALL)
+ fprintf (file, ", passed to call");
+ if (escape_mask & ESCAPE_BAD_CAST)
+ fprintf (file, ", bad cast");
+ if (escape_mask & ESCAPE_TO_RETURN)
+ fprintf (file, ", returned from func");
+ if (escape_mask & ESCAPE_TO_PURE_CONST)
+ fprintf (file, ", passed to pure/const");
+ if (escape_mask & ESCAPE_IS_GLOBAL)
+ fprintf (file, ", is global var");
+ if (escape_mask & ESCAPE_IS_PARM)
+ fprintf (file, ", is incoming pointer");
+ if (escape_mask & ESCAPE_UNKNOWN)
+ fprintf (file, ", unknown escape");
+ fprintf (file, " )");
+ }
- if (ann->default_def)
+ if (gimple_default_def (cfun, var))
{
fprintf (file, ", default def: ");
- print_generic_expr (file, ann->default_def, dump_flags);
+ print_generic_expr (file, gimple_default_def (cfun, var), dump_flags);
}
- if (ann->may_aliases)
+ if (may_aliases (var))
{
fprintf (file, ", may aliases: ");
dump_may_aliases_for (file, var);
}
+ if (get_subvars_for_var (var))
+ {
+ fprintf (file, ", sub-vars: ");
+ dump_subvars_for (file, var);
+ }
+
+ if (!is_gimple_reg (var))
+ {
+ if (memory_partition (var))
+ {
+ fprintf (file, ", belongs to partition: ");
+ print_generic_expr (file, memory_partition (var), dump_flags);
+ }
+
+ if (TREE_CODE (var) == MEMORY_PARTITION_TAG)
+ {
+ fprintf (file, ", partition symbols: ");
+ dump_decl_set (file, MPT_SYMBOLS (var));
+ }
+ }
+
fprintf (file, "\n");
}
fprintf (file, fmt_str_1, "VUSE operands", dfa_stats.num_vuses,
SCALE (size), LABEL (size));
- size = dfa_stats.num_v_may_defs * sizeof (tree *);
+ size = dfa_stats.num_vdefs * sizeof (tree *);
total += size;
- fprintf (file, fmt_str_1, "V_MAY_DEF operands", dfa_stats.num_v_may_defs,
- SCALE (size), LABEL (size));
-
- size = dfa_stats.num_v_must_defs * sizeof (tree *);
- total += size;
- fprintf (file, fmt_str_1, "V_MUST_DEF operands", dfa_stats.num_v_must_defs,
+ fprintf (file, fmt_str_1, "VDEF operands", dfa_stats.num_vdefs,
SCALE (size), LABEL (size));
size = dfa_stats.num_phis * sizeof (struct tree_phi_node);
}
-/* Collect DFA statistics and store them in the structure pointed by
+/* Collect DFA statistics and store them in the structure pointed to by
DFA_STATS_P. */
static void
memset ((void *)dfa_stats_p, 0, sizeof (struct dfa_stats_d));
/* Walk all the trees in the function counting references. Start at
- basic block 0, but don't stop at block boundaries. */
+ basic block NUM_FIXED_BLOCKS, but don't stop at block boundaries. */
pset = pointer_set_create ();
- for (i = bsi_start (BASIC_BLOCK (0)); !bsi_end_p (i); bsi_next (&i))
+ for (i = bsi_start (BASIC_BLOCK (NUM_FIXED_BLOCKS));
+ !bsi_end_p (i); bsi_next (&i))
walk_tree (bsi_stmt_ptr (i), collect_dfa_stats_r, (void *) dfa_stats_p,
pset);
tree t = *tp;
struct dfa_stats_d *dfa_stats_p = (struct dfa_stats_d *)data;
- if (t->common.ann)
+ if (t->base.ann)
{
- switch (ann_type (t->common.ann))
+ switch (ann_type (t->base.ann))
{
case STMT_ANN:
{
- stmt_ann_t ann = (stmt_ann_t) t->common.ann;
dfa_stats_p->num_stmt_anns++;
- dfa_stats_p->num_defs += NUM_DEFS (DEF_OPS (ann));
- dfa_stats_p->num_uses += NUM_USES (USE_OPS (ann));
- dfa_stats_p->num_v_may_defs +=
- NUM_V_MAY_DEFS (V_MAY_DEF_OPS (ann));
- dfa_stats_p->num_vuses += NUM_VUSES (VUSE_OPS (ann));
- dfa_stats_p->num_v_must_defs +=
- NUM_V_MUST_DEFS (V_MUST_DEF_OPS (ann));
+ dfa_stats_p->num_defs += NUM_SSA_OPERANDS (t, SSA_OP_DEF);
+ dfa_stats_p->num_uses += NUM_SSA_OPERANDS (t, SSA_OP_USE);
+ dfa_stats_p->num_vdefs += NUM_SSA_OPERANDS (t, SSA_OP_VDEF);
+ dfa_stats_p->num_vuses += NUM_SSA_OPERANDS (t, SSA_OP_VUSE);
break;
}
the function. */
static tree
-find_vars_r (tree *tp, int *walk_subtrees, void *data)
+find_vars_r (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
{
- struct walk_state *walk_state = (struct walk_state *) data;
-
/* If T is a regular variable that the optimizers are interested
in, add it to the list of variables. */
if (SSA_VAR_P (*tp))
- add_referenced_var (*tp, walk_state);
+ add_referenced_var (*tp);
/* Type, _DECL and constant nodes have no interesting children.
Ignore them. */
return NULL_TREE;
}
+/* Lookup UID in the referenced_vars hashtable and return the associated
+ variable. */
-/* Add VAR to the list of dereferenced variables.
+tree
+referenced_var_lookup (unsigned int uid)
+{
+ struct int_tree_map *h, in;
+ in.uid = uid;
+ h = (struct int_tree_map *) htab_find_with_hash (gimple_referenced_vars (cfun),
+ &in, uid);
+ gcc_assert (h || uid == 0);
+ if (h)
+ return h->to;
+ return NULL_TREE;
+}
- WALK_STATE contains a hash table used to avoid adding the same
- variable more than once. Note that this function assumes that
- VAR is a valid SSA variable. If WALK_STATE is NULL, no
- duplicate checking is done. */
+/* Check if TO is in the referenced_vars hash table and insert it if not.
+ Return true if it required insertion. */
-static void
-add_referenced_var (tree var, struct walk_state *walk_state)
+bool
+referenced_var_check_and_insert (tree to)
+{
+ struct int_tree_map *h, in;
+ void **loc;
+ unsigned int uid = DECL_UID (to);
+
+ in.uid = uid;
+ in.to = to;
+ h = (struct int_tree_map *) htab_find_with_hash (gimple_referenced_vars (cfun),
+ &in, uid);
+
+ if (h)
+ {
+ /* DECL_UID has already been entered in the table. Verify that it is
+ the same entry as TO. See PR 27793. */
+ gcc_assert (h->to == to);
+ return false;
+ }
+
+ h = GGC_NEW (struct int_tree_map);
+ h->uid = uid;
+ h->to = to;
+ loc = htab_find_slot_with_hash (gimple_referenced_vars (cfun),
+ h, uid, INSERT);
+ *(struct int_tree_map **) loc = h;
+ return true;
+}
+
+/* Lookup VAR UID in the default_defs hashtable and return the associated
+ variable. */
+
+tree
+gimple_default_def (struct function *fn, tree var)
{
- void **slot;
- var_ann_t v_ann;
+ struct int_tree_map *h, in;
+ gcc_assert (SSA_VAR_P (var));
+ in.uid = DECL_UID (var);
+ h = (struct int_tree_map *) htab_find_with_hash (DEFAULT_DEFS (fn),
+ &in,
+ DECL_UID (var));
+ if (h)
+ return h->to;
+ return NULL_TREE;
+}
- v_ann = get_var_ann (var);
+/* Insert the pair VAR's UID, DEF into the default_defs hashtable. */
- if (walk_state)
- slot = htab_find_slot (walk_state->vars_found, (void *) var, INSERT);
- else
- slot = NULL;
+void
+set_default_def (tree var, tree def)
+{
+ struct int_tree_map in;
+ struct int_tree_map *h;
+ void **loc;
- if (slot == NULL || *slot == NULL)
+ gcc_assert (SSA_VAR_P (var));
+ in.uid = DECL_UID (var);
+ if (!def && gimple_default_def (cfun, var))
+ {
+ loc = htab_find_slot_with_hash (DEFAULT_DEFS (cfun), &in,
+ DECL_UID (var), INSERT);
+ htab_remove_elt (DEFAULT_DEFS (cfun), *loc);
+ return;
+ }
+ gcc_assert (TREE_CODE (def) == SSA_NAME);
+ loc = htab_find_slot_with_hash (DEFAULT_DEFS (cfun), &in,
+ DECL_UID (var), INSERT);
+
+ /* Default definition might be changed by tail call optimization. */
+ if (!*loc)
{
- /* This is the first time we find this variable, add it to the
- REFERENCED_VARS array and annotate it with attributes that are
- intrinsic to the variable. */
- if (slot)
- *slot = (void *) var;
- v_ann->uid = num_referenced_vars;
- VARRAY_PUSH_TREE (referenced_vars, var);
-
- /* Global variables are always call-clobbered. */
- if (is_global_var (var))
- mark_call_clobbered (var);
+ h = GGC_NEW (struct int_tree_map);
+ h->uid = DECL_UID (var);
+ h->to = def;
+ *(struct int_tree_map **) loc = h;
+ }
+ else
+ {
+ h = (struct int_tree_map *) *loc;
+ SSA_NAME_IS_DEFAULT_DEF (h->to) = false;
+ h->to = def;
+ }
+
+ /* Mark DEF as the default definition for VAR. */
+ SSA_NAME_IS_DEFAULT_DEF (def) = true;
+}
+
+/* Add VAR to the list of referenced variables if it isn't already there. */
+
+void
+add_referenced_var (tree var)
+{
+ var_ann_t v_ann;
+
+ v_ann = get_var_ann (var);
+ gcc_assert (DECL_P (var));
+
+ /* Insert VAR into the referenced_vars has table if it isn't present. */
+ if (referenced_var_check_and_insert (var))
+ {
+ /* This is the first time we found this variable, annotate it with
+ attributes that are intrinsic to the variable. */
+
+ /* Tag's don't have DECL_INITIAL. */
+ if (MTAG_P (var))
+ return;
/* Scan DECL_INITIAL for pointer variables as they may contain
address arithmetic referencing the address of other
optimizers. */
&& !DECL_EXTERNAL (var)
/* It's not necessary to walk the initial value of non-constant
- public variables because it cannot be propagated by the
+ variables because it cannot be propagated by the
optimizers. */
- && (!TREE_PUBLIC (var) || !TREE_CONSTANT (var)))
- walk_tree (&DECL_INITIAL (var), find_vars_r, walk_state, 0);
+ && (TREE_CONSTANT (var) || TREE_READONLY (var)))
+ walk_tree (&DECL_INITIAL (var), find_vars_r, NULL, 0);
}
}
return var;
}
-/* Add a temporary variable to REFERENCED_VARS. This is similar to
- add_referenced_var, but is used by passes that need to add new temps to
- the REFERENCED_VARS array after the program has been scanned for
- variables. The variable will just receive a new UID and be added
- to the REFERENCED_VARS array without checking for duplicates. */
+/* Mark all the naked symbols in STMT for SSA renaming.
+
+ NOTE: This function should only be used for brand new statements.
+ If the caller is modifying an existing statement, it should use the
+ combination push_stmt_changes/pop_stmt_changes. */
void
-add_referenced_tmp_var (tree var)
-{
- add_referenced_var (var, NULL);
-}
-
-
-/* Add all the non-SSA variables found in STMT's operands to the bitmap
- VARS_TO_RENAME. */
-
-void
-mark_new_vars_to_rename (tree stmt, bitmap vars_to_rename)
+mark_symbols_for_renaming (tree stmt)
{
+ tree op;
ssa_op_iter iter;
- tree val;
- bitmap vars_in_vops_to_rename;
- bool found_exposed_symbol = false;
- int v_may_defs_before, v_may_defs_after;
- int v_must_defs_before, v_must_defs_after;
-
- vars_in_vops_to_rename = BITMAP_ALLOC (NULL);
-
- /* Before re-scanning the statement for operands, mark the existing
- virtual operands to be renamed again. We do this because when new
- symbols are exposed, the virtual operands that were here before due to
- aliasing will probably be removed by the call to get_stmt_operand.
- Therefore, we need to flag them to be renamed beforehand.
-
- We flag them in a separate bitmap because we don't really want to
- rename them if there are not any newly exposed symbols in the
- statement operands. */
- v_may_defs_before = NUM_V_MAY_DEFS (STMT_V_MAY_DEF_OPS (stmt));
- v_must_defs_before = NUM_V_MUST_DEFS (STMT_V_MUST_DEF_OPS (stmt));
-
- FOR_EACH_SSA_TREE_OPERAND (val, stmt, iter,
- SSA_OP_VMAYDEF | SSA_OP_VUSE | SSA_OP_VMUSTDEF)
- {
- if (!DECL_P (val))
- val = SSA_NAME_VAR (val);
- bitmap_set_bit (vars_in_vops_to_rename, var_ann (val)->uid);
- }
- /* Now force an operand re-scan on the statement and mark any newly
- exposed variables. */
update_stmt (stmt);
- v_may_defs_after = NUM_V_MAY_DEFS (STMT_V_MAY_DEF_OPS (stmt));
- v_must_defs_after = NUM_V_MUST_DEFS (STMT_V_MUST_DEF_OPS (stmt));
-
- FOR_EACH_SSA_TREE_OPERAND (val, stmt, iter, SSA_OP_ALL_OPERANDS)
- {
- if (DECL_P (val))
- {
- found_exposed_symbol = true;
- bitmap_set_bit (vars_to_rename, var_ann (val)->uid);
- }
- }
-
- /* If we found any newly exposed symbols, or if there are fewer VDEF
- operands in the statement, add the variables we had set in
- VARS_IN_VOPS_TO_RENAME to VARS_TO_RENAME. We need to check for
- vanishing VDEFs because in those cases, the names that were formerly
- generated by this statement are not going to be available anymore. */
- if (found_exposed_symbol
- || v_may_defs_before > v_may_defs_after
- || v_must_defs_before > v_must_defs_after)
- bitmap_ior_into (vars_to_rename, vars_in_vops_to_rename);
-
- BITMAP_FREE (vars_in_vops_to_rename);
+ /* Mark all the operands for renaming. */
+ FOR_EACH_SSA_TREE_OPERAND (op, stmt, iter, SSA_OP_ALL_OPERANDS)
+ if (DECL_P (op))
+ mark_sym_for_renaming (op);
}
+
/* Find all variables within the gimplified statement that were not previously
visible to the function and add them to the referenced variables list. */
tree t = *tp;
if (TREE_CODE (t) == VAR_DECL && !var_ann (t))
- add_referenced_tmp_var (t);
+ {
+ add_referenced_var (t);
+ mark_sym_for_renaming (t);
+ }
if (IS_TYPE_OR_DECL_P (t))
*walk_subtrees = 0;
}
-/* Mark all call-clobbered variables for renaming. */
+/* If EXP is a handled component reference for a structure, return the
+ base variable. The access range is delimited by bit positions *POFFSET and
+ *POFFSET + *PMAX_SIZE. The access size is *PSIZE bits. If either
+ *PSIZE or *PMAX_SIZE is -1, they could not be determined. If *PSIZE
+ and *PMAX_SIZE are equal, the access is non-variable. */
-void
-mark_call_clobbered_vars_to_rename (void)
+tree
+get_ref_base_and_extent (tree exp, HOST_WIDE_INT *poffset,
+ HOST_WIDE_INT *psize,
+ HOST_WIDE_INT *pmax_size)
{
- unsigned i;
- bitmap_iterator bi;
- EXECUTE_IF_SET_IN_BITMAP (call_clobbered_vars, 0, i, bi)
+ HOST_WIDE_INT bitsize = -1;
+ HOST_WIDE_INT maxsize = -1;
+ tree size_tree = NULL_TREE;
+ tree bit_offset = bitsize_zero_node;
+ bool seen_variable_array_ref = false;
+
+ gcc_assert (!SSA_VAR_P (exp));
+
+ /* First get the final access size from just the outermost expression. */
+ if (TREE_CODE (exp) == COMPONENT_REF)
+ size_tree = DECL_SIZE (TREE_OPERAND (exp, 1));
+ else if (TREE_CODE (exp) == BIT_FIELD_REF)
+ size_tree = TREE_OPERAND (exp, 1);
+ else
{
- tree var = referenced_var (i);
- bitmap_set_bit (vars_to_rename, var_ann (var)->uid);
+ enum machine_mode mode = TYPE_MODE (TREE_TYPE (exp));
+ if (mode == BLKmode)
+ size_tree = TYPE_SIZE (TREE_TYPE (exp));
+ else
+ bitsize = GET_MODE_BITSIZE (mode);
}
-}
-
-/* If REF is a COMPONENT_REF for a structure that can have sub-variables, and
- we know where REF is accessing, return the variable in REF that has the
- sub-variables. If the return value is not NULL, POFFSET will be the
- offset, in bits, of REF inside the return value, and PSIZE will be the
- size, in bits, of REF inside the return value. */
-
-tree
-okay_component_ref_for_subvars (tree ref, HOST_WIDE_INT *poffset,
- HOST_WIDE_INT *psize)
-{
- tree result = NULL;
- HOST_WIDE_INT bitsize;
- HOST_WIDE_INT bitpos;
- tree offset;
- enum machine_mode mode;
- int unsignedp;
- int volatilep;
-
- gcc_assert (!SSA_VAR_P (ref));
- *poffset = 0;
- *psize = (unsigned int) -1;
-
- if (ref_contains_array_ref (ref))
- return result;
- ref = get_inner_reference (ref, &bitsize, &bitpos, &offset, &mode,
- &unsignedp, &volatilep, false);
- if (TREE_CODE (ref) == INDIRECT_REF)
- return result;
- else if (offset == NULL && bitsize != -1 && SSA_VAR_P (ref))
+ if (size_tree != NULL_TREE)
{
- *poffset = bitpos;
- *psize = bitsize;
- if (get_subvars_for_var (ref) != NULL)
- return ref;
+ if (! host_integerp (size_tree, 1))
+ bitsize = -1;
+ else
+ bitsize = TREE_INT_CST_LOW (size_tree);
}
- else if (SSA_VAR_P (ref))
+
+ /* Initially, maxsize is the same as the accessed element size.
+ In the following it will only grow (or become -1). */
+ maxsize = bitsize;
+
+ /* Compute cumulative bit-offset for nested component-refs and array-refs,
+ and find the ultimate containing object. */
+ while (1)
{
- if (get_subvars_for_var (ref) != NULL)
- return ref;
+ switch (TREE_CODE (exp))
+ {
+ case BIT_FIELD_REF:
+ bit_offset = size_binop (PLUS_EXPR, bit_offset,
+ TREE_OPERAND (exp, 2));
+ break;
+
+ case COMPONENT_REF:
+ {
+ tree field = TREE_OPERAND (exp, 1);
+ tree this_offset = component_ref_field_offset (exp);
+
+ if (this_offset && TREE_CODE (this_offset) == INTEGER_CST)
+ {
+ this_offset = size_binop (MULT_EXPR,
+ fold_convert (bitsizetype,
+ this_offset),
+ bitsize_unit_node);
+ bit_offset = size_binop (PLUS_EXPR,
+ bit_offset, this_offset);
+ bit_offset = size_binop (PLUS_EXPR, bit_offset,
+ DECL_FIELD_BIT_OFFSET (field));
+ }
+ else
+ {
+ tree csize = TYPE_SIZE (TREE_TYPE (TREE_OPERAND (exp, 0)));
+ /* We need to adjust maxsize to the whole structure bitsize.
+ But we can subtract any constant offset seen sofar,
+ because that would get us out of the structure otherwise. */
+ if (maxsize != -1
+ && csize && host_integerp (csize, 1))
+ {
+ maxsize = (TREE_INT_CST_LOW (csize)
+ - TREE_INT_CST_LOW (bit_offset));
+ }
+ else
+ maxsize = -1;
+ }
+ }
+ break;
+
+ case ARRAY_REF:
+ case ARRAY_RANGE_REF:
+ {
+ tree index = TREE_OPERAND (exp, 1);
+ tree low_bound = array_ref_low_bound (exp);
+ tree unit_size = array_ref_element_size (exp);
+
+ if (! integer_zerop (low_bound))
+ index = fold_build2 (MINUS_EXPR, TREE_TYPE (index),
+ index, low_bound);
+ index = size_binop (MULT_EXPR,
+ fold_convert (sizetype, index), unit_size);
+ if (TREE_CODE (index) == INTEGER_CST)
+ {
+ index = size_binop (MULT_EXPR,
+ fold_convert (bitsizetype, index),
+ bitsize_unit_node);
+ bit_offset = size_binop (PLUS_EXPR, bit_offset, index);
+
+ /* An array ref with a constant index up in the structure
+ hierarchy will constrain the size of any variable array ref
+ lower in the access hierarchy. */
+ seen_variable_array_ref = false;
+ }
+ else
+ {
+ tree asize = TYPE_SIZE (TREE_TYPE (TREE_OPERAND (exp, 0)));
+ /* We need to adjust maxsize to the whole array bitsize.
+ But we can subtract any constant offset seen sofar,
+ because that would get us outside of the array otherwise. */
+ if (maxsize != -1
+ && asize && host_integerp (asize, 1))
+ {
+ maxsize = (TREE_INT_CST_LOW (asize)
+ - TREE_INT_CST_LOW (bit_offset));
+ }
+ else
+ maxsize = -1;
+
+ /* Remember that we have seen an array ref with a variable
+ index. */
+ seen_variable_array_ref = true;
+ }
+ }
+ break;
+
+ case REALPART_EXPR:
+ break;
+
+ case IMAGPART_EXPR:
+ bit_offset = size_binop (PLUS_EXPR, bit_offset,
+ bitsize_int (bitsize));
+ break;
+
+ case VIEW_CONVERT_EXPR:
+ /* ??? We probably should give up here and bail out. */
+ break;
+
+ default:
+ goto done;
+ }
+
+ exp = TREE_OPERAND (exp, 0);
}
- return NULL_TREE;
+ done:
+
+ /* We need to deal with variable arrays ending structures such as
+ struct { int length; int a[1]; } x; x.a[d]
+ struct { struct { int a; int b; } a[1]; } x; x.a[d].a
+ struct { struct { int a[1]; } a[1]; } x; x.a[0][d], x.a[d][0]
+ where we do not know maxsize for variable index accesses to
+ the array. The simplest way to conservatively deal with this
+ is to punt in the case that offset + maxsize reaches the
+ base type boundary. */
+ if (seen_variable_array_ref
+ && maxsize != -1
+ && host_integerp (TYPE_SIZE (TREE_TYPE (exp)), 1)
+ && TREE_INT_CST_LOW (bit_offset) + maxsize
+ == TREE_INT_CST_LOW (TYPE_SIZE (TREE_TYPE (exp))))
+ maxsize = -1;
+
+ /* ??? Due to negative offsets in ARRAY_REF we can end up with
+ negative bit_offset here. We might want to store a zero offset
+ in this case. */
+ *poffset = TREE_INT_CST_LOW (bit_offset);
+ *psize = bitsize;
+ *pmax_size = maxsize;
+
+ return exp;
}