better available constant handling

diff --git a/ir/opt/gvn_pre.c b/ir/opt/gvn_pre.c
index 6f1f860..7a6d1b1 100644 (file)
--- a/ir/opt/gvn_pre.c
+++ b/ir/opt/gvn_pre.c
@@ -1259,24 +1259,23 @@ static ir_mode *is_partially_redundant(ir_node *block, ir_node *expr, ir_node *v
                trans_expr = get_translated(pred_block, expr);
                trans_value = identify(trans_expr);
 
-               /* value might be available through a constant */
-               if (is_irn_constlike(trans_expr)) {
-                       avail_expr = trans_expr;
-                       if (get_irn_idx(trans_expr) > environ->last_idx) {
-                               /* limit new constants */
-                               ir_mode   *cmode  = get_irn_mode(trans_expr);
-                               ir_tarval *upper = new_tarval_from_long(127, cmode);
-                               ir_tarval *lower = new_tarval_from_long(-127, cmode);
-                               ir_tarval *c     = get_Const_tarval(trans_expr);
-
-                               if (tarval_cmp(lower, c) != ir_relation_greater_equal &&
-                                   tarval_cmp(c, upper) != ir_relation_greater_equal) {
-                                       avail_expr = NULL;
-                               }
+               avail_expr = (ir_node*)ir_valueset_lookup(pred_info->avail_out, trans_value);
+               /* value might be available through a not yet existing constant */
+               if (avail_expr == NULL && is_irn_constlike(trans_expr)) {
+                       /* limit range of new constants */
+                       ir_mode   *cmode  = get_irn_mode(trans_expr);
+                       ir_tarval *upper = new_tarval_from_long(127, cmode);
+                       ir_tarval *lower = new_tarval_from_long(-127, cmode);
+                       ir_tarval *c     = get_Const_tarval(trans_expr);
+
+                       if (tarval_cmp(lower, c) != ir_relation_greater_equal &&
+                               tarval_cmp(c, upper) != ir_relation_greater_equal) {
+                               avail_expr = NULL;
+                       } else {
+                               avail_expr = trans_expr;
                        }
-           } else {
-                       avail_expr = (ir_node*)ir_valueset_lookup(pred_info->avail_out, trans_value);
-               }
+           }
+
                DB((dbg, LEVEL_3, "avail_expr %+F\n", avail_expr));
 
                if (avail_expr == NULL) {
@@ -1628,7 +1627,6 @@ static void hoist_high(ir_node *block, void *ctx)
                if (is_memop(expr) || is_Proj(expr))
                        continue;
 
-               /* for each path to block */
                for (pos = 0; pos < arity; ++pos) {
                        /* standard target is predecessor block */
                        ir_node    *target     = get_Block_cfgpred_block(block, pos);