implemented constant load access for pointer arithmetic (old initializers only)

[r22088]

diff --git a/ir/opt/ldstopt.c b/ir/opt/ldstopt.c
index 0a42f29..12c41ab 100644 (file)
--- a/ir/opt/ldstopt.c
+++ b/ir/opt/ldstopt.c
@@ -307,6 +307,31 @@ static ir_entity *find_constant_entity(ir_node *ptr)
 
                        /* try next */
                        ptr = get_Sel_ptr(ptr);
+               } else if (is_Add(ptr)) {
+                       ir_node *l = get_Add_left(ptr);
+                       ir_node *r = get_Add_right(ptr);
+
+                       if (get_irn_mode(l) == get_irn_mode(ptr) && is_Const(r))
+                               ptr = l;
+                       else if (get_irn_mode(r) == get_irn_mode(ptr) && is_Const(l))
+                               ptr = r;
+                       else
+                               return NULL;
+
+                       /* for now, we support only one addition, reassoc should fold all others */
+                       if (! is_SymConst(ptr) && !is_Sel(ptr))
+                               return NULL;
+               } else if (is_Sub(ptr)) {
+                       ir_node *l = get_Sub_left(ptr);
+                       ir_node *r = get_Sub_right(ptr);
+
+                       if (get_irn_mode(l) == get_irn_mode(ptr) &&     is_Const(r))
+                               ptr = l;
+                       else
+                               return NULL;
+                       /* for now, we support only one substraction, reassoc should fold all others */
+                       if (! is_SymConst(ptr) && !is_Sel(ptr))
+                               return NULL;
                } else
                        return NULL;
        }
@@ -331,8 +356,10 @@ static long get_Sel_array_index_long(ir_node *n, int dim) {
  */
 static compound_graph_path *rec_get_accessed_path(ir_node *ptr, int depth) {
        compound_graph_path *res = NULL;
-       ir_entity           *root, *field;
-       int                 path_len, pos;
+       ir_entity           *root, *field, *ent;
+       int                 path_len, pos, idx;
+       tarval              *tv;
+       ir_type             *tp;
 
        if (is_SymConst(ptr)) {
                /* a SymConst. If the depth is 0, this is an access to a global
@@ -342,10 +369,11 @@ static compound_graph_path *rec_get_accessed_path(ir_node *ptr, int depth) {
                assert(get_SymConst_kind(ptr) == symconst_addr_ent);
                root = get_SymConst_entity(ptr);
                res = (depth == 0) ? NULL : new_compound_graph_path(get_entity_type(root), depth);
-       } else {
-               assert(is_Sel(ptr));
+       } else if (is_Sel(ptr)) {
                /* it's a Sel, go up until we find the root */
                res = rec_get_accessed_path(get_Sel_ptr(ptr), depth+1);
+               if (res == NULL)
+                       return NULL;
 
                /* fill up the step in the path at the current position */
                field    = get_Sel_entity(ptr);
@@ -357,6 +385,98 @@ static compound_graph_path *rec_get_accessed_path(ir_node *ptr, int depth) {
                        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));
                }
+       } else if (is_Add(ptr)) {
+               ir_node *l = get_Add_left(ptr);
+               ir_node *r = get_Add_right(ptr);
+               ir_mode *mode;
+
+               if (is_Const(r)) {
+                       ptr = l;
+                       tv  = get_Const_tarval(r);
+               } else {
+                       ptr = r;
+                       tv  = get_Const_tarval(l);
+               }
+ptr_arith:
+               mode = get_tarval_mode(tv);
+
+               /* ptr must be a Sel or a SymConst, this was checked in find_constant_entity() */
+               if (is_Sel(ptr)) {
+                       field = get_Sel_entity(ptr);
+               } else {
+                       field = get_SymConst_entity(ptr);
+               }
+               idx = 0;
+               for (ent = field;;) {
+                       tp = get_entity_type(ent);
+                       if (! is_Array_type(tp))
+                               break;
+                       ent = get_array_element_entity(tp);
+                       ++idx;
+               }
+               /* should be at least ONE array */
+               if (idx == 0)
+                       return NULL;
+
+               res = rec_get_accessed_path(ptr, depth + idx);
+               if (res == NULL)
+                       return NULL;
+
+               path_len = get_compound_graph_path_length(res);
+               pos      = path_len - depth - idx;
+
+               for (ent = field;;) {
+                       unsigned size;
+                       tarval   *sz, *tv_index, *tlower, *tupper;
+                       long     index;
+                       ir_node  *bound;
+
+                       tp = get_entity_type(ent);
+                       if (! is_Array_type(tp))
+                               break;
+                       ent = get_array_element_entity(tp);
+                       set_compound_graph_path_node(res, pos, ent);
+
+                       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);
+
+                       if (tv_index == tarval_bad || tv == tarval_bad)
+                               return NULL;
+
+                       assert(get_array_n_dimensions(tp) == 1 && "multiarrays not implemented");
+                       bound  = get_array_lower_bound(tp, 0);
+                       tlower = computed_value(bound);
+                       bound  = get_array_upper_bound(tp, 0);
+                       tupper = computed_value(bound);
+
+                       if (tlower == tarval_bad || tupper == tarval_bad)
+                               return NULL;
+
+                       if (tarval_cmp(tv_index, tlower) & pn_Cmp_Lt)
+                               return NULL;
+                       if (tarval_cmp(tupper, tv_index) & pn_Cmp_Lt)
+                               return NULL;
+
+                       /* ok, bounds check finished */
+                       index = get_tarval_long(tv_index);
+                       set_compound_graph_path_array_index(res, pos, index);
+                       ++pos;
+               }
+               if (! tarval_is_null(tv)) {
+                       /* hmm, wrong access */
+                       return NULL;
+               }
+       } else if (is_Sub(ptr)) {
+               ir_node *l = get_Sub_left(ptr);
+               ir_node *r = get_Sub_right(ptr);
+
+               ptr = l;
+               tv  = get_Const_tarval(r);
+               tv  = tarval_neg(tv);
+               goto ptr_arith;
        }
        return res;
 }  /* rec_get_accessed_path */