get rid of most Optimisation warning: found add/sub with const

[r19757]

diff --git a/ir/ir/iropt.c b/ir/ir/iropt.c
index 27cafe8..ff4a610 100644 (file)
--- a/ir/ir/iropt.c
+++ b/ir/ir/iropt.c
@@ -1990,6 +1990,7 @@ static ir_node *transform_node_AddSub(ir_node *n) {
                        }
                }
        }
+
        return n;
 }  /* transform_node_AddSub */
 
@@ -2042,6 +2043,17 @@ static ir_node *transform_node_Add(ir_node *n) {
        b = get_Add_right(n);
 
        mode = get_irn_mode(n);
+
+       if (mode_is_reference(mode)) {
+               ir_mode *lmode = get_irn_mode(a);
+
+               if (is_Const(b) && is_Const_null(b) && mode_is_int(lmode)) {
+                       /* an Add(a, NULL) is a hidden Conv */
+                       dbg_info *dbg = get_irn_dbg_info(n);
+                       return new_rd_Conv(dbg, current_ir_graph, get_nodes_block(n), a, mode);
+               }
+       }
+
        HANDLE_BINOP_PHI(tarval_add, a, b, c, mode);
 
        /* for FP these optimizations are only allowed if fp_strict_algebraic is disabled */
@@ -2051,7 +2063,7 @@ static ir_node *transform_node_Add(ir_node *n) {
        if (mode_is_num(mode)) {
                /* the following code leads to endless recursion when Mul are replaced by a simple instruction chain */
                if (!is_arch_dep_running() && a == b && mode_is_int(mode)) {
-                       ir_node *block = get_irn_n(n, -1);
+                       ir_node *block = get_nodes_block(n);
 
                        n = new_rd_Mul(
                                get_irn_dbg_info(n),
@@ -2156,6 +2168,16 @@ static ir_node *transform_node_Sub(ir_node *n) {
 
        mode = get_irn_mode(n);
 
+       if (mode_is_int(mode)) {
+               ir_mode *lmode = get_irn_mode(a);
+
+               if (is_Const(b) && is_Const_null(b) && mode_is_reference(lmode)) {
+                       /* a Sub(a, NULL) is a hidden Conv */
+                       dbg_info *dbg = get_irn_dbg_info(n);
+                       return new_rd_Conv(dbg, current_ir_graph, get_nodes_block(n), a, mode);
+               }
+       }
+
 restart:
        HANDLE_BINOP_PHI(tarval_sub, a, b, c, mode);