* compile.c (iseq_compile_each): emit opt_str_freeze if the #freeze

  method is called on a static string literal with no arguments.

* defs/id.def (firstline): add freeze so idFreeze is available

* insns.def (opt_str_freeze): add opt_str_freeze instruction which
  pushes a frozen string literal without allocating a new object if
  String#freeze is not overriden

* string.c (Init_String): define String#freeze

* vm.c (vm_init_redefined_flag): define BOP_FREEZE on String class as
  a basic operation

* vm_insnhelper.h: ditto

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@43627 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 11 insertions, 0 deletions

diff --git a/compile.c b/compile.c
index f3f5f2d75a..00ae3011e7 100644
--- a/compile.c
+++ b/compile.c
@@ -4314,6 +4314,17 @@ iseq_compile_each(rb_iseq_t *iseq, LINK_ANCHOR *ret, NODE * node, int poped)
 	break;
       }
       case NODE_CALL:
+	if (node->nd_recv && nd_type(node->nd_recv) == NODE_STR &&
+	    node->nd_mid == idFreeze && node->nd_args == NULL)
+	{
+	    VALUE str = rb_fstring(node->nd_recv->nd_lit);
+	    iseq_add_mark_object(iseq, str);
+	    ADD_INSN1(ret, line, opt_str_freeze, str);
+	    if (poped) {
+		ADD_INSN(ret, line, pop);
+	    }
+	    break;
+	}
       case NODE_FCALL:
       case NODE_VCALL:{		/* VCALL: variable or call */
 	/*