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 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

 /* This Source Code Form is subject to the terms of the Mozilla Public

  * License, v. 2.0. If a copy of the MPL was not distributed with this

  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

 /*

  *

  * Date:    24 Nov 2003

  * SUMMARY: Testing for recursion check in js_EmitTree

  *

  * See http://bugzilla.mozilla.org/show_bug.cgi?id=226507

  * Igor's comments:

  *

  * "For example, with N in the test  set to 35, I got on my RedHat

  * Linux 10 box a segmentation fault from js after setting the stack limit

  * to 100K. When I set the stack limit to 20K I still got the segmentation fault.

  * Only after -s was changed to 15K, too-deep recursion was detected:

  *

  ~/w/js/x> ulimit -s

  100

  ~/w/js/x> js  fintest.js

  Segmentation fault

  ~/w/js/x> js -S $((20*1024)) fintest.js

  Segmentation fault

  ~/w/js/x> js -S $((15*1024)) fintest.js

  fintest.js:19: InternalError: too much recursion

  *

  * After playing with numbers it seems that while processing try/finally the

  * recursion in js_Emit takes 10 times more space the corresponding recursion

  * in the parser."

  *

  *

  * Note the use of the new -S option to the JS shell to limit stack size.

  * See http://bugzilla.mozilla.org/show_bug.cgi?id=225061. This in turn

  * can be passed to the JS shell by the test driver's -o option, as in:

  *

  * perl jsDriver.pl -e smdebug -fTEST.html -o "-S 100" -l js1_5/Regress

  *

  */

 //-----------------------------------------------------------------------------

 var UBound = 0;

 var BUGNUMBER = 226507;

 var summary = 'Testing for recursion check in js_EmitTree';

 var status = '';

 var statusitems = [];

 var actual = '';

 var actualvalues = [];

 var expect= '';

 var expectedvalues = [];

 /*

  * With stack limit 100K on Linux debug build even N=30 already can cause

  * stack overflow; use 35 to trigger it for sure.

  */

 var N = 350;

 var counter = 0;

 function f()

 {

   ++counter;

 }

 /*

  * Example: if N were 3, this is what |source|

  * would end up looking like:

  *

  *     try { f(); } finally {

  *     try { f(); } finally {

  *     try { f(); } finally {

  *     f(1,1,1,1);

  *     }}}

  *

  */

 var source = "".concat(

   repeat_str("try { f(); } finally {\n", N),

   "f(",

   repeat_str("1,", N),

   "1);\n",

   repeat_str("}", N));

 // Repeat it for additional stress testing

 source += source;

 /*

  * In Rhino, eval() always uses interpreted mode.

  * To use compiled mode, use Script.exec() instead.

  */

 if (typeof Script == 'undefined')

 {

   print('Test skipped. Script not defined.');

   expect = actual = 0;

 }

 else

 {

   try

   {

     var script = Script(source);

     script();

     status = inSection(1);

     actual = counter;

     expect = (N + 1) * 2;

   }

   catch(ex)

   {

     actual = ex + '';

   }

 }

 addThis();

 //-----------------------------------------------------------------------------

 test();

 //-----------------------------------------------------------------------------

 function repeat_str(str, repeat_count)

 {

   var arr = new Array(--repeat_count);

   while (repeat_count != 0)

     arr[--repeat_count] = str;

   return str.concat.apply(str, arr);

 }

 function addThis()

 {

   statusitems[UBound] = status;

   actualvalues[UBound] = actual;

   expectedvalues[UBound] = expect;

   UBound++;

 }

 function test()

 {

   enterFunc('test');

   printBugNumber(BUGNUMBER);

   printStatus(summary);

   for (var i=0; i<UBound; i++)

   {

     reportCompare(expectedvalues[i], actualvalues[i], statusitems[i]);

   }

   exitFunc ('test');

 }