With bytecode flushing and lazy feedback allocation, we need to call
%PrepareForOptimization before we call %OptimizeFunctionOnNextCall,
ideally after declaring the function.

Bug: v8:8801, v8:8394, v8:9183
Change-Id: I3fb257282a30f6526a376a3afdedb44786320d34
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1648255
Commit-Queue: Mathias Bynens <mathias@chromium.org>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Reviewed-by: Mythri Alle <mythria@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62119}

The previous JavaScript version created way too many ConsStrings for
longer strings, i.e. when using String.fromCharCode together with
Function.prototype.apply and arrays of char codes.

This version now always allocates sequential strings and therefore uses
way less memory when turning longer character sequences into strings,
and therefore fixes the memory regression on Google Maps.

BUG=chromium:609831
R=yangguo@chromium.org

Review-Url: https://codereview.chromium.org/2004733002
Cr-Commit-Position: refs/heads/master@{#36427}

R=jkummerow@chromium.org
BUG=

Review URL: https://chromiumcodereview.appspot.com/15743006

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@14769 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

BUG=

Review URL: https://chromiumcodereview.appspot.com/14296009

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@14315 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

Encapsulate the helper functions in mjsunit.js.
Now only exposes the exception class and the assertXXX functions.

Make assertEquals use === instead of ==.
This prevents a lot of possiblefalse positives in tests, and avoids
having to do assertTrue(expected === actual) when you need it.

Fixed some tests that were either buggy or assuming == test.

Review URL: http://codereview.chromium.org/6869007

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@7628 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

Review URL: http://codereview.chromium.org/3291015

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5433 ce2b1a6d-e550-0410-aec6-3dcde31c8c00