string.c: use predefined IDs for minor bloat reduction

* string.c (id_to_s): remove redundant variable
  (rb_obj_as_string): trade id_to_s for idTo_s
  (rb_str_equal): replace rb_intern(...) with pre-defined ID
  (rb_str_cmp_m): ditto
  (rb_str_match): ditto
  (str_upto_each): ditto
  (rb_str_sum): ditto
  (Init_String): remove id_to_s initialization

This leads to a minor size reduction on my x86 (32-bit) system:

   text	   data	    bss	    dec	    hex	filename
 129373	      8	     32	 129413	  1f985	string.o-orig
 129082	      8	      8	 129098	  1f84a	string.o

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@52479 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

2 files changed, 18 insertions, 10 deletions

diff --git a/ChangeLog b/ChangeLog
index 2ba77afa47..4693463b4e 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,14 @@
+Sat Nov  7 12:18:05 2015  Eric Wong  <e@80x24.org>
+
+	* string.c (id_to_s): remove redundant variable
+	  (rb_obj_as_string): trade id_to_s for idTo_s
+	  (rb_str_equal): replace rb_intern(...) with pre-defined ID
+	  (rb_str_cmp_m): ditto
+	  (rb_str_match): ditto
+	  (str_upto_each): ditto
+	  (rb_str_sum): ditto
+	  (Init_String): remove id_to_s initialization
+
 Sat Nov  7 11:40:05 2015  Eric Wong  <e@80x24.org>
 
 	* thread.c (rb_cThreadShield): make static
diff --git a/string.c b/string.c
index 3a0089669c..d834754743 100644
--- a/string.c
+++ b/string.c
@@ -17,6 +17,7 @@
 #include "probes.h"
 #include "gc.h"
 #include <assert.h>
+#include "id.h"
 
 #define BEG(no) (regs->beg[(no)])
 #define END(no) (regs->end[(no)])
@@ -1227,8 +1228,6 @@ str_shared_replace(VALUE str, VALUE str2)
     }
 }
 
-static ID id_to_s;
-
 VALUE
 rb_obj_as_string(VALUE obj)
 {
@@ -1237,7 +1236,7 @@ rb_obj_as_string(VALUE obj)
     if (RB_TYPE_P(obj, T_STRING)) {
 	return obj;
     }
-    str = rb_funcall(obj, id_to_s, 0);
+    str = rb_funcall(obj, idTo_s, 0);
     if (!RB_TYPE_P(str, T_STRING))
 	return rb_any_to_s(obj);
     OBJ_INFECT(str, obj);
@@ -2761,7 +2760,7 @@ rb_str_equal(VALUE str1, VALUE str2)
 {
     if (str1 == str2) return Qtrue;
     if (!RB_TYPE_P(str2, T_STRING)) {
-	if (!rb_respond_to(str2, rb_intern("to_str"))) {
+	if (!rb_respond_to(str2, idTo_str)) {
 	    return Qfalse;
 	}
 	return rb_equal(str2, str1);
@@ -2816,7 +2815,7 @@ rb_str_cmp_m(VALUE str1, VALUE str2)
     int result;
 
     if (!RB_TYPE_P(str2, T_STRING)) {
-	VALUE tmp = rb_check_funcall(str2, rb_intern("to_str"), 0, 0);
+	VALUE tmp = rb_check_funcall(str2, idTo_str, 0, 0);
 	if (RB_TYPE_P(tmp, T_STRING)) {
 	    result = rb_str_cmp(str1, tmp);
 	}
@@ -3219,7 +3218,7 @@ rb_str_match(VALUE x, VALUE y)
 
       generic:
       default:
-	return rb_funcall(y, rb_intern("=~"), 1, x);
+	return rb_funcall(y, idEqTilde, 1, x);
     }
 }
 
@@ -3699,7 +3698,7 @@ str_upto_each(VALUE beg, VALUE end, int excl, int (*each)(VALUE, VALUE), VALUE a
 	    }
 	}
 	else {
-	    ID op = excl ? '<' : rb_intern("<=");
+	    ID op = excl ? '<' : idLE;
 	    VALUE args[2], fmt = rb_obj_freeze(rb_usascii_str_new_cstr("%.*d"));
 
 	    args[0] = INT2FIX(width);
@@ -8044,7 +8043,7 @@ rb_str_sum(int argc, VALUE *argv, VALUE str)
                 sum = rb_funcall(sum, '+', 1, LONG2FIX(sum0));
             }
 
-            mod = rb_funcall(INT2FIX(1), rb_intern("<<"), 1, INT2FIX(bits));
+            mod = rb_funcall(INT2FIX(1), idLTLT, 1, INT2FIX(bits));
             mod = rb_funcall(mod, '-', 1, INT2FIX(1));
             sum = rb_funcall(sum, '&', 1, mod);
         }
@@ -9368,8 +9367,6 @@ Init_String(void)
     rb_define_method(rb_cString, "valid_encoding?", rb_str_valid_encoding_p, 0);
     rb_define_method(rb_cString, "ascii_only?", rb_str_is_ascii_only_p, 0);
 
-    id_to_s = rb_intern("to_s");
-
     rb_fs = Qnil;
     rb_define_variable("$;", &rb_fs);
     rb_define_variable("$-F", &rb_fs);