/* Do not fiddle about polymorphy. */
if (is_Class_type(get_entity_owner(ent)) &&
- ((get_entity_n_overwrites(ent) != 0) ||
- (get_entity_n_overwrittenby(ent) != 0) ) )
- return NULL;
+ ((get_entity_n_overwrites(ent) != 0) ||
+ (get_entity_n_overwrittenby(ent) != 0) ) )
+ return NULL;
if (variability_constant == get_entity_variability(ent))
- return ent;
+ return ent;
if (is_Array_type(tp)) {
/* check bounds */
}
}
+/**
+ * Return the Selection index of a Sel node from dimension n
+ */
static long get_Sel_array_index_long(ir_node *n, int dim) {
ir_node *index = get_Sel_index(n, dim);
assert(get_irn_op(index) == op_Const);
return get_tarval_long(get_Const_tarval(index));
}
-compound_graph_path *rec_get_accessed_path(ir_node *ptr, int depth) {
- compound_graph_path *res;
+/**
+ * Returns the accessed component graph path for an
+ * node computing an address.
+ *
+ * @param ptr the node computing the address
+ * @param depth current depth in steps upward from the root
+ * of the address
+ */
+static compound_graph_path *rec_get_accessed_path(ir_node *ptr, int depth) {
+ compound_graph_path *res = NULL;
+ entity *root, *field;
+ int path_len, pos;
+
if (get_irn_op(ptr) == op_SymConst) {
+ /* a SymConst. If the depth is 0, this is an access to a global
+ * entity and we don't need a component path, else we know
+ * at least it's length.
+ */
assert(get_SymConst_kind(ptr) == symconst_addr_ent);
- entity *root = get_SymConst_entity(ptr);
- res = new_compound_graph_path(get_entity_type(root), depth);
- } else {
+ root = get_SymConst_entity(ptr);
+ res = (depth == 0) ? NULL : new_compound_graph_path(get_entity_type(root), depth);
+ }
+ else {
assert(get_irn_op(ptr) == op_Sel);
+ /* it's a Sel, go up until we find the root */
res = rec_get_accessed_path(get_Sel_ptr(ptr), depth+1);
- entity *field = get_Sel_entity(ptr);
- int path_len = get_compound_graph_path_length(res);
- int pos = path_len - depth -1;
+
+ /* fill up the step in the path at the current position */
+ field = get_Sel_entity(ptr);
+ path_len = get_compound_graph_path_length(res);
+ pos = path_len - depth - 1;
set_compound_graph_path_node(res, pos, field);
+
if (is_Array_type(get_entity_owner(field))) {
assert(get_Sel_n_indexs(ptr) == 1 && "multi dim arrays not implemented");
set_compound_graph_path_array_index(res, pos, get_Sel_array_index_long(ptr, 0));
return res;
}
-compound_graph_path *get_accessed_path(ir_node *ptr) {
+/** Returns an access path or NULL. The access path is only
+ * valid, if the graph is in phase_high and _no_ address computation is used.
+ */
+static compound_graph_path *get_accessed_path(ir_node *ptr) {
return rec_get_accessed_path(ptr, 0);
}
-
/**
* optimize a Load
*/
{
ldst_info_t *info = get_irn_link(load);
ir_mode *load_mode = get_Load_mode(load);
- ir_node *pred, *mem, *ptr;
+ ir_node *pred, *mem, *ptr, *new_node;
entity *ent;
int res = 0;
+ /* do NOT touch volatile loads for now */
+ if (get_Load_volatility(load) == volatility_is_volatile)
+ return 0;
+
/* the address of the load to be optimized */
ptr = get_Load_ptr(load);
/*
- * Check if we can remove the exception form a Load:
- * this can be done, if the address is from an Sel(Alloc) and
- * the Sel type is a subtype of the alloc type.
+ * Check if we can remove the exception from a Load:
+ * This can be done, if the address is from an Sel(Alloc) and
+ * the Sel type is a subtype of the allocated type.
*
* This optimizes some often used OO constructs,
* like x = new O; x->t;
if (get_irn_op(ptr) == op_Sel) {
ir_node *mem = get_Sel_mem(ptr);
- if (get_irn_op(mem) == op_Alloc) {
+ if (get_irn_op(skip_Proj(mem)) == op_Alloc) {
/* ok, check the types */
entity *ent = get_Sel_entity(ptr);
type *s_type = get_entity_type(ent);
if (is_subclass_of(s_type, a_type)) {
/* ok, condition met: there can't be an exception because
- * alloc guarantees that enough memory was allocated */
+ * Alloc guarantees that enough memory was allocated */
exchange(info->projs[pn_Load_X_except], new_Bad());
info->projs[pn_Load_X_except] = NULL;
+ res = 1;
}
}
}
- else if (get_irn_op(ptr) == op_Alloc) {
+ else if ((get_irn_op(skip_Proj(ptr)) == op_Alloc) ||
+ ((get_irn_op(ptr) == op_Cast) && (get_irn_op(skip_Proj(get_Cast_op(ptr))) == op_Alloc))) {
/* simple case: a direct load after an Alloc. Firm Alloc throw
* an exception in case of out-of-memory. So, there is no way for an
* exception in this load.
*/
exchange(info->projs[pn_Load_X_except], new_Bad());
info->projs[pn_Load_X_except] = NULL;
+ res = 1;
}
}
- /* do NOT touch volatile loads for now */
- if (get_Load_volatility(load) == volatility_is_volatile)
- return 0;
+ /* the mem of the Load. Must still be returned after optimization */
+ mem = get_Load_mem(load);
if (! info->projs[pn_Load_res] && ! info->projs[pn_Load_X_except]) {
/* a Load which value is neither used nor exception checked, remove it */
- mem = get_Load_mem(load);
exchange(info->projs[pn_Load_M], mem);
return 1;
}
- /* the mem of the Load. Must still be returned after optimization */
- mem = get_Load_mem(load);
-
/* Load from a constant polymorphic field, where we can resolve
polymorphy. */
- ir_node *new_node = transform_node_Load(load);
+ new_node = transform_node_Load(load);
if (new_node != load) {
if (info->projs[pn_Load_M]) {
exchange(info->projs[pn_Load_M], mem);
if (info->projs[pn_Load_X_except]) {
exchange(info->projs[pn_Load_X_except], new_Bad());
info->projs[pn_Load_X_except] = NULL;
+ res = 1;
}
if (variability_constant == get_entity_variability(ent)
- && is_atomic_entity(ent)) { /* Might not be atomic after
- lowering of Sels. In this
- case we could also load, but
- it's more complicated. */
+ && is_atomic_entity(ent)) {
+ /* Might not be atomic after
+ lowering of Sels. In this
+ case we could also load, but
+ it's more complicated. */
/* more simpler case: we load the content of a constant value:
* replace it by the constant itself
*/
/* no memory */
- if (info->projs[pn_Load_M])
+ if (info->projs[pn_Load_M]) {
exchange(info->projs[pn_Load_M], mem);
+ res = 1;
+ }
/* no result :-) */
if (info->projs[pn_Load_res]) {
DBG_OPT_RC(load, c);
exchange(info->projs[pn_Load_res], c);
-
return 1;
}
}
}
else if (variability_constant == get_entity_variability(ent)) {
- printf(">>>>>>>>>>>>> Found access to constant entity %s in function %s\n", get_entity_name(ent),
- get_entity_name(get_irg_entity(current_ir_graph)));
- printf(" load: "); DDMN(load);
- printf(" ptr: "); DDMN(ptr);
+ compound_graph_path *path = get_accessed_path(ptr);
+
+ if (path) {
+ ir_node *c;
+
+ assert(is_proper_compound_graph_path(path, get_compound_graph_path_length(path)-1));
+ /*
+ {
+ int j;
+ for (j = 0; j < get_compound_graph_path_length(path); ++j) {
+ entity *node = get_compound_graph_path_node(path, j);
+ fprintf(stdout, ".%s", get_entity_name(node));
+ if (is_Array_type(get_entity_owner(node)))
+ fprintf(stdout, "[%d]", get_compound_graph_path_array_index(path, j));
+ }
+ printf("\n");
+ }
+ */
- compound_graph_path *path = get_accessed_path(ptr);
- assert(is_proper_compound_graph_path(path, get_compound_graph_path_length(path)-1));
- ir_node *c = get_compound_ent_value_by_path(ent, path);
+ c = get_compound_ent_value_by_path(ent, path);
+ free_compound_graph_path(path);
- printf(" cons: "); DDMN(c);
-
- if (info->projs[pn_Load_M])
- exchange(info->projs[pn_Load_M], mem);
- if (info->projs[pn_Load_res])
- exchange(info->projs[pn_Load_res], copy_const_value(c));
-
- {
- int j;
- for (j = 0; j < get_compound_graph_path_length(path); ++j) {
- entity *node = get_compound_graph_path_node(path, j);
- fprintf(stdout, ".%s", get_entity_name(node));
- if (is_Array_type(get_entity_owner(node)))
- fprintf(stdout, "[%d]", get_compound_graph_path_array_index(path, j));
- }
- printf("\n");
- }
+ /* printf(" cons: "); DDMN(c); */
+ if (info->projs[pn_Load_M]) {
+ exchange(info->projs[pn_Load_M], mem);
+ res = 1;
+ }
+ if (info->projs[pn_Load_res]) {
+ exchange(info->projs[pn_Load_res], copy_const_value(c));
+ return 1;
+ }
+ }
+ else {
+ /* We can not determine a correct access path. E.g., in jack, we load
+ a byte from an object to generate an exception. Happens in test program
+ Reflectiontest.
+ printf(">>>>>>>>>>>>> Found access to constant entity %s in function %s\n", get_entity_name(ent),
+ get_entity_name(get_irg_entity(current_ir_graph)));
+ printf(" load: "); DDMN(load);
+ printf(" ptr: "); DDMN(ptr);
+ */
+ }
}
-
- /* we changed the irg, but try further */
- res = 1;
}
-
-
}
/* Check, if the address of this load is used more than once.
* If not, this load cannot be removed in any case. */
if (get_irn_out_n(ptr) <= 1)
- return 0;
+ return res;
- /* follow the memory chain as long as there are only Loads */
+ /* follow the memory chain as long as there are only Loads
+ * and try to replace current Load or Store by a previous one
+ */
for (pred = skip_Proj(mem); ; pred = skip_Proj(get_Load_mem(pred))) {
-
/*
* BEWARE: one might think that checking the modes is useless, because
* if the pointers are identical, they refer to the same object.
- * This is only true in strong typed languages, not is C were the following
+ * This is only true in strong typed languages, not in C were the following
* is possible a = *(type1 *)p; b = *(type2 *)p ...
*/
* OR they are in the same block. In the latter case the Load cannot
* throw an exception when the previous Store was quiet.
*
- * Why we need to check for Store Exc? If the Store cannot be executed (ROM)
- * the exception handler might simply jump into the load block :-(
+ * Why we need to check for Store Exception? If the Store cannot
+ * be executed (ROM) the exception handler might simply jump into
+ * the load block :-(
* We could make it a little bit better if we would know that the exception
* handler of the Store jumps directly to the end...
*/
if ((!pred_info->projs[pn_Store_X_except] && !info->projs[pn_Load_X_except]) ||
get_nodes_block(load) == get_nodes_block(pred)) {
- DBG_OPT_RAW(load, pred);
- exchange( info->projs[pn_Load_res], get_Store_value(pred) );
+ ir_node *value = get_Store_value(pred);
+ DBG_OPT_RAW(load, value);
if (info->projs[pn_Load_M])
exchange(info->projs[pn_Load_M], mem);
/* no exception */
if (info->projs[pn_Load_X_except])
exchange( info->projs[pn_Load_X_except], new_Bad());
+
+ if (info->projs[pn_Load_res])
+ exchange(info->projs[pn_Load_res], value);
+
return 1;
}
}
* OR they are in the same block. In the later case the Load cannot
* throw an exception when the previous Load was quiet.
*
- * Here, there is no need to check if the previos Load has an exception hander because
- * they would have exact the same exception...
+ * Here, there is no need to check if the previous Load has an exception
+ * hander because they would have exact the same exception...
*/
if (! info->projs[pn_Load_X_except] || get_nodes_block(load) == get_nodes_block(pred)) {
ldst_info_t *pred_info = get_irn_link(pred);
if (pred_info->projs[pn_Load_res]) {
/* we need a data proj from the previous load for this optimization */
- exchange( info->projs[pn_Load_res], pred_info->projs[pn_Load_res] );
+ if (info->projs[pn_Load_res])
+ exchange(info->projs[pn_Load_res], pred_info->projs[pn_Load_res]);
+
if (info->projs[pn_Load_M])
exchange(info->projs[pn_Load_M], mem);
}
if (info->projs[pn_Load_res]) {
set_Proj_pred(info->projs[pn_Load_res], pred);
set_nodes_block(info->projs[pn_Load_res], get_nodes_block(pred));
+ pred_info->projs[pn_Load_res] = info->projs[pn_Load_res];
}
if (info->projs[pn_Load_M]) {
/* Actually, this if should not be necessary. Construct the Loads
walk_env_t env;
assert(get_irg_phase_state(irg) != phase_building);
+ assert(get_irg_pinned(irg) != op_pin_state_floats &&
+ "LoadStore optimization needs pinned graph");
if (!get_opt_redundant_LoadStore())
return;
projects / libfirm / blobdiff