Constify.

[r14066]

ir/ir/irnode.c

@@ -1037,7 +1037,7 @@ set_Return_res(ir_node *node, int pos, ir_node *res){
 	set_irn_n(node, pos + RETURN_RESULT_OFFSET, res);
 }
 
-tarval *(get_Const_tarval)(ir_node *node) {
+tarval *(get_Const_tarval)(const ir_node *node) {
 	return _get_Const_tarval(node);
 }
 
@@ -1579,7 +1579,7 @@ get_Phi_preds_arr(ir_node *node) {
 }
 
 int
-get_Phi_n_preds(ir_node *node) {
+get_Phi_n_preds(const ir_node *node) {
 	assert(is_Phi(node) || is_Phi0(node));
 	return (get_irn_arity(node));
 }
@@ -1591,7 +1591,7 @@ void set_Phi_n_preds(ir_node *node, int n_preds) {
 */
 
 ir_node *
-get_Phi_pred(ir_node *node, int pos) {
+get_Phi_pred(const ir_node *node, int pos) {
 	assert(is_Phi(node) || is_Phi0(node));
 	return get_irn_n(node, pos);
 }

ir/ir/irnode.h

@@ -483,7 +483,7 @@ typedef enum {
   CNST_NO_CONST =  4  /**< The node is no const at all. */
 } cnst_classify_t;
 
-tarval  *get_Const_tarval(ir_node *node);
+tarval  *get_Const_tarval(const ir_node *node);
 void     set_Const_tarval(ir_node *node, tarval *con);
 
 /**
@@ -899,8 +899,8 @@ int       is_Phi(const ir_node *n);
 int       is_Phi0(const ir_node *n);
 /* These routines also work for Filter nodes in interprocedural view. */
 ir_node **get_Phi_preds_arr(ir_node *node);
-int       get_Phi_n_preds(ir_node *node);
-ir_node  *get_Phi_pred(ir_node *node, int pos);
+int       get_Phi_n_preds(const ir_node *node);
+ir_node  *get_Phi_pred(const ir_node *node, int pos);
 void      set_Phi_pred(ir_node *node, int pos, ir_node *pred);
 
 ir_node  *get_Filter_pred(ir_node *node);

ir/ir/irnode_t.h

@@ -919,7 +919,7 @@ _is_Block_dead(const ir_node *block) {
 	}
 }
 
-static INLINE tarval *_get_Const_tarval(ir_node *node) {
+static INLINE tarval *_get_Const_tarval(const ir_node *node) {
 	assert(_get_irn_op(node) == op_Const);
 	return node->attr.con.tv;
 }