Simplify StringCharCodeAt in non-crankshaft codegen.

test/mjsunit/string-slices.js

Index: test/mjsunit/string-slices.js
diff --git a/test/mjsunit/string-slices.js b/test/mjsunit/string-slices.js
index 7c40229c75def951ac4379af31bf2754ae0bd5c3..0d205cc182d1ea396f530f2662cc7924c8198600 100755
--- a/test/mjsunit/string-slices.js
+++ b/test/mjsunit/string-slices.js
@@ -25,7 +25,7 @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-// Flags: --string-slices --expose-externalize-string
+// Flags: --string-slices --expose-externalize-string --allow-natives-syntax

[Lasse Reichstein, 2011/11/09 12:48:11]

If string-slices is on by default now, we should remove the flag here.

 
 var s = 'abcdefghijklmn';
 assertEquals(s, s.substr());
@@ -100,14 +100,7 @@ for (var i = 5; i < 25; i++) {
 
 // Keep creating strings to to force allocation failure on substring creation.
 var x = "0123456789ABCDEF";
-x += x;  // 2^5
-x += x;
-x += x;
-x += x;
-x += x;
-x += x;  // 2^10
-x += x;
-x += x;
+for (var i = 0; i < 8; i++) x += x;
 var xl = x.length;
 var cache = [];
 for (var i = 0; i < 1000; i++) {
@@ -119,14 +112,7 @@ for (var i = 0; i < 1000; i++) {
 
 // Same with two-byte strings
 var x = "\u2028123456789ABCDEF";
-x += x;  // 2^5
-x += x;
-x += x;
-x += x;
-x += x;
-x += x;  // 2^10
-x += x;
-x += x;
+for (var i = 0; i < 8; i++) x += x;
 var xl = x.length;
 var cache = [];
 for (var i = 0; i < 1000; i++) {
@@ -202,3 +188,21 @@ assertEquals(a.slice(1,-1), b);
 assertTrue(/3456789qwe/.test(a));
 assertEquals(5, a.indexOf("678"));
 assertEquals("12345", a.split("6")[0]);
+
+// Create a slice with an external string as parent string.
+var c = a.slice(1,-1);
+
+function test_crankshaft() {
+  for (var i = 0; i < 20; i++) {
+    assertEquals(b.charAt(i), a.charAt(i + 1));
+    assertEquals(b.charAt(i), c.charAt(i));
+    assertEquals(b.charAt(4), c.charAt(4));
+    assertTrue(/3456789qwe/.test(c));
+    assertEquals(4, c.indexOf("678"));
+    assertEquals("2345", c.split("6")[0]);
+  }
+}
+
+test_crankshaft();
+%OptimizeFunctionOnNextCall(test_crankshaft);
+test_crankshaft();