Cache template literal callSiteObj

test/mjsunit/harmony/templates.js

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Flags: --harmony-templates
 
 var num = 5;
 var str = "str";
 function fn() { return "result"; }
 var obj = {
@@ skipping 312 matching lines @@
   assertEquals(1, calls);
 })();
 
 
 (function testUTF16ByteOrderMark() {
   assertEquals("\uFEFFtest", `\uFEFFtest`);
   assertEquals("\uFEFFtest", eval("`\uFEFFtest`"));
 })();
 
 
+(function testCallSiteCaching() {
+  var callSites = [];
+  function tag(cs) { callSites.push(cs); }
+  var a = 1;
+  var b = 2;
+
+  tag`head${a}tail`;
+  tag`head${b}tail`;
+
+  assertEquals(2, callSites.length);
+  assertSame(callSites[0], callSites[1]);
+
+  eval("tag`head${a}tail`");
+  assertEquals(3, callSites.length);
+  assertSame(callSites[1], callSites[2]);
+
+  eval("tag`head${b}tail`");
+  assertEquals(4, callSites.length);
+  assertSame(callSites[2], callSites[3]);
+
+  (new Function("tag", "a", "b", "return tag`head${a}tail`;"))(tag, 1, 2);
+  assertEquals(5, callSites.length);
+  assertSame(callSites[3], callSites[4]);
+
+  (new Function("tag", "a", "b", "return tag`head${b}tail`;"))(tag, 1, 2);
+  assertEquals(6, callSites.length);
+  assertSame(callSites[4], callSites[5]);
+
+  callSites = [];
+
+  tag`foo${a}bar`;
+  tag`foo\${.}bar`;
+  assertEquals(2, callSites[0].length);
+  assertEquals(1, callSites[1].length);
+})();

[arv (Not doing code reviews), 2014/11/19 06:09:11]

Maybe a test that has same values in the array but different values in the raw
arrays?

+
+
 (function testExtendedArrayPrototype() {
   Object.defineProperty(Array.prototype, 0, {
     set: function() {
       assertUnreachable();
     }
   });
   function tag(){}
   tag`a${1}b`;
 })();