panic() instead of assert(0).

[libfirm] / ir / opt / ldstopt.c

diff --git a/ir/opt/ldstopt.c b/ir/opt/ldstopt.c
index 58b24ec..91347a7 100644 (file)
--- a/ir/opt/ldstopt.c
+++ b/ir/opt/ldstopt.c
@@ -386,11 +386,12 @@ static compound_graph_path *rec_get_accessed_path(ir_node *ptr, int depth) {
                        set_compound_graph_path_array_index(res, pos, get_Sel_array_index_long(ptr, 0));
                }
        } else if (is_Add(ptr)) {
-               ir_node *l = get_Add_left(ptr);
-               ir_node *r = get_Add_right(ptr);
-               ir_mode *mode;
+               ir_node *l    = get_Add_left(ptr);
+               ir_node *r    = get_Add_right(ptr);
+               ir_mode *mode = get_irn_mode(ptr);
+               tarval  *tmp;
 
-               if (is_Const(r)) {
+               if (is_Const(r) && get_irn_mode(l) == mode) {
                        ptr = l;
                        tv  = get_Const_tarval(r);
                } else {
@@ -399,6 +400,7 @@ static compound_graph_path *rec_get_accessed_path(ir_node *ptr, int depth) {
                }
 ptr_arith:
                mode = get_tarval_mode(tv);
+               tmp  = tv;
 
                /* ptr must be a Sel or a SymConst, this was checked in find_constant_entity() */
                if (is_Sel(ptr)) {
@@ -419,10 +421,10 @@ ptr_arith:
                        size = get_type_size_bytes(get_entity_type(ent));
                        sz   = new_tarval_from_long(size, mode);
 
-                       tv_index = tarval_div(tv, sz);
-                       tv       = tarval_mod(tv, sz);
+                       tv_index = tarval_div(tmp, sz);
+                       tmp      = tarval_mod(tmp, sz);
 
-                       if (tv_index == tarval_bad || tv == tarval_bad)
+                       if (tv_index == tarval_bad || tmp == tarval_bad)
                                return NULL;
 
                        assert(get_array_n_dimensions(tp) == 1 && "multiarrays not implemented");
@@ -442,7 +444,7 @@ ptr_arith:
                        /* ok, bounds check finished */
                        ++idx;
                }
-               if (! tarval_is_null(tv)) {
+               if (! tarval_is_null(tmp)) {
                        /* access to some struct/union member */
                        return NULL;
                }
@@ -500,7 +502,8 @@ ptr_arith:
  * 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);
+       compound_graph_path *gr = rec_get_accessed_path(ptr, 0);
+       return gr;
 }  /* get_accessed_path */
 
 typedef struct path_entry {
@@ -538,7 +541,7 @@ static ir_node *rec_find_compound_ent_value(ir_node *ptr, path_entry *next) {
                                        continue;
                                }
                        }
-                       if (p->index >= n)
+                       if (p->index >= (int) n)
                                return NULL;
                        initializer = get_initializer_compound_value(initializer, p->index);
 
@@ -1188,6 +1191,7 @@ static unsigned optimize_load(ir_node *load)
                                                                assert(is_proper_compound_graph_path(path, get_compound_graph_path_length(path)-1));
 
                                                                value = get_compound_ent_value_by_path(ent, path);
+                                                               DB((dbg, LEVEL_1, "  Constant access at %F%F resulted in %+F\n", ent, path, value));
                                                                free_compound_graph_path(path);
                                                        }
                                                }
@@ -1352,18 +1356,61 @@ static unsigned follow_Mem_chain_for_Store(ir_node *store, ir_node *curr) {
        return res;
 }  /* follow_Mem_chain_for_Store */
 
+/** find entity used as base for an address calculation */
+static ir_entity *find_entity(ir_node *ptr)
+{
+       switch(get_irn_opcode(ptr)) {
+       case iro_SymConst:
+               return get_SymConst_entity(ptr);
+       case iro_Sel: {
+               ir_node *pred = get_Sel_ptr(ptr);
+               if (get_irg_frame(get_irn_irg(ptr)) == pred)
+                       return get_Sel_entity(ptr);
+
+               return find_entity(pred);
+       }
+       case iro_Sub:
+       case iro_Add: {
+               ir_node *left = get_binop_left(ptr);
+               ir_node *right;
+               if (mode_is_reference(get_irn_mode(left)))
+                       return find_entity(left);
+               right = get_binop_right(ptr);
+               if (mode_is_reference(get_irn_mode(right)))
+                       return find_entity(right);
+               return NULL;
+       }
+       default:
+               return NULL;
+       }
+}
+
 /**
  * optimize a Store
  *
  * @param store  the Store node
  */
 static unsigned optimize_store(ir_node *store) {
-       ir_node *ptr, *mem;
+       ir_node   *ptr;
+       ir_node   *mem;
+       ir_entity *entity;
 
        if (get_Store_volatility(store) == volatility_is_volatile)
                return 0;
 
-       ptr = get_Store_ptr(store);
+       ptr    = get_Store_ptr(store);
+       entity = find_entity(ptr);
+
+       /* a store to an entity which is never read is unnecessary */
+       if (entity != NULL && !(get_entity_usage(entity) & ir_usage_read)) {
+               ldst_info_t *info = get_irn_link(store);
+               if (info->projs[pn_Store_X_except] == NULL) {
+                       exchange(info->projs[pn_Store_M], get_Store_mem(store));
+                       kill_node(store);
+                       reduce_adr_usage(ptr);
+                       return DF_CHANGED;
+               }
+       }
 
        /* Check, if the address of this Store is used more than once.
         * If not, this Store cannot be removed in any case. */
@@ -2145,8 +2192,8 @@ void optimize_load_store(ir_graph *irg) {
        assure_postdoms(irg);
 
        if (get_opt_alias_analysis()) {
-               assure_irg_address_taken_computed(irg);
-               assure_irp_globals_address_taken_computed();
+               assure_irg_entity_usage_computed(irg);
+               assure_irp_globals_entity_usage_computed();
        }
 
        obstack_init(&env.obst);
@@ -2166,6 +2213,7 @@ void optimize_load_store(ir_graph *irg) {
        /* Handle graph state */
        if (env.changes) {
                set_irg_outs_inconsistent(irg);
+               set_irg_entity_usage_state(irg, ir_entity_usage_not_computed);
        }
 
        if (env.changes & CF_CHANGED) {