Consider out-of-bounds accesses as escaping uses.

test/mjsunit/compiler/escape-analysis.js

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-// Flags: --allow-natives-syntax --use-escape-analysis
+// Flags: --allow-natives-syntax --use-escape-analysis --expose-gc
 
 
 // Test stores on a join path.
 (function testJoin() {
   function constructor() {
     this.a = 0;
   }
   function join(mode, expected) {
     var object = new constructor();
     if (mode) {
@@ skipping 195 matching lines @@
   }
   function test(closure) {
     assertEquals(45, closure(10));
     assertEquals(45, closure(10));
     assertEquals(10, closure(50000));
   }
   test(osr1);
   test(osr2);
   test(osr3);
 })();
+
+
+// Test out-of-bounds access on captured objects.
+(function testOOB() {
+  function cons1() {
+    this.x = 1;
+    this.y = 2;
+    this.z = 3;
+  }
+  function cons2() {
+    this.a = 7;
+  }
+  function oob(constructor, branch) {
+    var o = new constructor();
+    if (branch) {
+      return o.a;
+    } else {
+      return o.z;
+    }
+  }
+  assertEquals(3, oob(cons1, false));
+  assertEquals(3, oob(cons1, false));
+  assertEquals(7, oob(cons2, true));
+  assertEquals(7, oob(cons2, true));
+  gc();  // Clears type feedback of constructor call.
+  assertEquals(7, oob(cons2, true));
+  assertEquals(7, oob(cons2, true));
+  %OptimizeFunctionOnNextCall(oob);
+  assertEquals(7, oob(cons2, true));
+})();