[turbofan] Teach escape analysis about ConvertTaggedHoleToUndefined.

The EscapeStatusAnalysis didn't know anything about the simplified
operator ConvertTaggedHoleToUndefined, thus leading to a crash. We
now just handled it by pretending that any allocation that goes into
such a node escapes.

BUG=chromium:669451
R=tebbi@chromium.org

Review-Url: https://codereview.chromium.org/2533263002
Cr-Commit-Position: refs/heads/master@{#41359}

src/compiler/escape-analysis.cc

@@ -796,6 +796,7 @@ bool EscapeStatusAnalysis::CheckUsesForEscape(Node* uses, Node* rep,
       case IrOpcode::kSelect:
       // TODO(mstarzinger): The following list of operators will eventually be
       // handled by the EscapeAnalysisReducer (similar to ObjectIsSmi).
+      case IrOpcode::kConvertTaggedHoleToUndefined:
       case IrOpcode::kStringEqual:
       case IrOpcode::kStringLessThan:
       case IrOpcode::kStringLessThanOrEqual:

test/mjsunit/regress/regress-crbug-669451.js

+// Copyright 2016 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: --allow-natives-syntax
+
+function foo() {
+  var a = [,];
+  a[0] = {}
+  a[0].toString = FAIL;
+}
+try { foo(); } catch (e) {}
+try { foo(); } catch (e) {}
+%OptimizeFunctionOnNextCall(foo);
+try { foo(); } catch (e) {}