* string.c (rb_str_append): performance improvement.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@14992 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,7 @@
+Fri Jan 11 16:55:21 2008  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* string.c (rb_str_append): performance improvement.
+
 Fri Jan 11 12:35:56 2008  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* configure.in: moved broken syscall checks from process.c etc.

string.c

@@ -1194,25 +1194,25 @@ rb_str_append(VALUE str, VALUE str2)
     int cr, cr2;
 
     StringValue(str2);
-    enc = rb_enc_check(str, str2);
-    cr = ENC_CODERANGE(str);
-    if ((cr2 = ENC_CODERANGE(str2)) > cr) cr = cr2;
-    rb_str_modify(str);
     if (RSTRING_LEN(str2) > 0) {
 	if (STR_ASSOC_P(str)) {
 	    long len = RSTRING_LEN(str)+RSTRING_LEN(str2);
+	    enc = rb_enc_check(str, str2);
+	    cr = ENC_CODERANGE(str);
+	    if ((cr2 = ENC_CODERANGE(str2)) > cr) cr = cr2;
+	    rb_str_modify(str);
 	    REALLOC_N(RSTRING(str)->as.heap.ptr, char, len+1);
 	    memcpy(RSTRING(str)->as.heap.ptr + RSTRING(str)->as.heap.len,
 		   RSTRING_PTR(str2), RSTRING_LEN(str2)+1);
 	    RSTRING(str)->as.heap.len = len;
+	    rb_enc_associate(str, enc);
+	    ENC_CODERANGE_SET(str, cr);
 	}
 	else {
-	    rb_str_buf_append(str, str2);
+	    return rb_str_buf_append(str, str2);
 	}
     }
     OBJ_INFECT(str, str2);
-    rb_enc_associate(str, enc);
-    ENC_CODERANGE_SET(str, cr);
     return str;
 }