Reduce regexp compiler stack size when not optimizing regexps

test/mjsunit/regress/regress-475705.js

Index: test/mjsunit/regress/regress-475705.js
diff --git a/test/mjsunit/regress/regress-475705.js b/test/mjsunit/regress/regress-475705.js
new file mode 100644
index 0000000000000000000000000000000000000000..ff96e041b101e12a04b2c55a13ca66938dff3a74
--- /dev/null
+++ b/test/mjsunit/regress/regress-475705.js
@@ -0,0 +1,63 @@
+// Copyright 2015 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.
+
+// Crankshaft changes the stack usage and messes up the binary search for the
+// stack depth that causes a stack overflow.  The issue only arises without
+// regexp optimization, which can happen on pages that create a lot of regexps.
+// Flags: --nocrankshaft --noregexp-optimization
+
+// Should not crash with a stack overflow in the regexp compiler, even when the
+// JS has used most of the stack.
+function use_space_then_do_test(depth) {
+  try {
+    // The "+ depth" is to avoid the regexp compilation cache.
+    var regexp_src = repeat(".(.)", 12) + depth;
+    use_space(depth, regexp_src);
+    return true;
+  } catch (e) {
+    assertFalse(("" + e).indexOf("tack") == -1);  // Check for [Ss]tack.
+    return false;
+  }
+}
+
+function use_space(n, regexp_src) {
+  if (--n == 0) {
+    do_test(regexp_src);
+    return;
+  }
+  use_space(n, regexp_src);
+}
+
+function repeat(str, n) {
+  var answer = "";
+  while (n-- != 0) {
+    answer += str;
+  }
+  return answer;
+}
+
+var subject = repeat("y", 200);
+
+function do_test(regexp_src) {
+  var re = new RegExp(regexp_src);
+  re.test(subject);
+}
+
+function try_different_stack_limits() {
+  var lower = 100;
+  var higher = 100000;
+  while (lower < higher - 1) {
+    var average = Math.floor((lower + higher) / 2);
+    if (use_space_then_do_test(average)) {
+      lower = average;
+    } else {
+      higher = average;
+    }
+  }
+  for (var i = lower - 5; i < higher + 5; i++) {
+    use_space_then_do_test(i);
+  }
+}
+
+try_different_stack_limits();