S390: Initial test changes and files checkin.

test/mjsunit/regress/regress-crbug-178790.js

Index: test/mjsunit/regress/regress-crbug-178790.js
diff --git a/test/mjsunit/regress/regress-crbug-178790.js b/test/mjsunit/regress/regress-crbug-178790.js
index 25cc96b852effd4b7e4d10a72d1b28911fe8e0a8..f18f9918c85947df9e225b2be11c61699b9d0450 100644
--- a/test/mjsunit/regress/regress-crbug-178790.js
+++ b/test/mjsunit/regress/regress-crbug-178790.js
@@ -28,6 +28,10 @@
 // Create a regexp in the form of a?a?...a? so that fully
 // traversing the entire graph would be prohibitively expensive.
 // This should not cause time out.
+// S390X uses more stack space for recursion calls.
+
+// Flags: --stack-size=8192

[Jakob Kummerow, 2016/03/15 14:58:04]

This is a lot, considering that the default value is 984K, and on Windows a
process will get killed when it uses more than 1024K.

Have you tested this on all platforms and operating systems? What's special
about this test's stack consumption? What happens when you don't set the extra
flag? Would it make sense to set an s390 specific V8_DEFAULT_STACK_SIZE_KB value
in globals.h instead? 

+
 var r1 = "";
 for (var i = 0; i < 1000; i++) {
   r1 += "a?";