- BugFix: constants must be evaluated BEFORE congruence checks

[r20758]

diff --git a/ir/opt/combo.c b/ir/opt/combo.c
index dd5e66d..32db696 100644 (file)
--- a/ir/opt/combo.c
+++ b/ir/opt/combo.c
@@ -1136,6 +1136,13 @@ static void compute_Add(node_t *node) {
        }
 }  /* compute_Add */
 
+/**
+ * Returns true if a type is a constant.
+ */
+static int is_con(const lattice_elem_t type) {
+       return is_entity(type.sym.entity_p) || tarval_is_constant(type.tv);
+}
+
 /**
  * (Re-)compute the type for a Sub. Special case: both nodes are congruent.
  *
@@ -1153,19 +1160,23 @@ static void compute_Sub(node_t *node) {
                node->type.tv = tarval_top;
                return;
        }
-
        if (a.tv == tarval_top || b.tv == tarval_top) {
                node->type.tv = tarval_top;
+       } else if (is_con(a) && is_con(b)) {
+               if (is_tarval(a.tv) && is_tarval(b.tv)) {
+                       node->type.tv = tarval_sub(a.tv, b.tv);
+               } else if (is_tarval(a.tv) && tarval_is_null(a.tv)) {
+                       node->type = b;
+               } else if (is_tarval(b.tv) && tarval_is_null(b.tv)) {
+                       node->type = a;
+               } else {
+                       node->type.tv = tarval_bottom;
+               }
        } else if (r->part == l->part) {
                ir_mode *mode = get_irn_mode(sub);
                node->type.tv = get_mode_null(mode);
-       } else if (a.tv == tarval_bottom || b.tv == tarval_bottom) {
-               node->type.tv = tarval_bottom;
        } else {
-               if (is_tarval(a.tv) && is_tarval(b.tv))
-                       node->type.tv = tarval_sub(a.tv, b.tv);
-               else
-                       node->type.tv = tarval_bottom;
+               node->type.tv = tarval_bottom;
        }
 }  /* compute_Sub */
 
@@ -1190,12 +1201,12 @@ static void compute_Proj_Cmp(node_t *node, ir_node *cmp) {
        if (!mode_is_float(get_irn_mode(l->node)) || pnc == pn_Cmp_Lt ||  pnc == pn_Cmp_Gt) {
                if (a.tv == tarval_top || b.tv == tarval_top) {
                        node->type.tv = tarval_top;
+               } else if (is_con(a) && is_con(b)) {
+                       default_compute(node);
                } else if (r->part == l->part) {
                        node->type.tv = new_tarval_from_long(pnc & pn_Cmp_Eq, mode_b);
-               } else if (a.tv == tarval_bottom || b.tv == tarval_bottom) {
-                       node->type.tv = tarval_bottom;
                } else {
-                       default_compute(node);
+                       node->type.tv = tarval_bottom;
                }
        } else {
                default_compute(node);
@@ -1559,7 +1570,7 @@ void combo(ir_graph *irg) {
 
        /* register a debug mask */
        FIRM_DBG_REGISTER(dbg, "firm.opt.combo");
-       firm_dbg_set_mask(dbg, SET_LEVEL_3);
+       //firm_dbg_set_mask(dbg, SET_LEVEL_3);
 
        DB((dbg, LEVEL_1, "Doing COMBO for %+F\n", irg));