This is in preparation for moving unsafe jsc shell functions to $vm.
Created attachment 326833 [details]
Thanks for the review. Landed in r224800: <http://trac.webkit.org/r224800>.
Re-opened since this is blocked by bug 179684
It turns out that there's a bug in the Cloop build that can result in some stack values being wrongly nullified by the stack sanitizer (see https://bugs.webkit.org/show_bug.cgi?id=179936). This bug was triggered because the addition of the $vm object bumped allocation sufficiently such that a slow path allocation is triggered at just the right moment, which in turn, ran the stack sanitizer and manifested the bug.
Incidentally, Saam added some properties to $vm (in r224938). This perturbed the allocation pattern sufficiently such that the CLoop stack sanitizer bug is now hidden again.
Since the bug isn't due to this patch to add the --useDollarVM=true option, and the effects of the bug has been masked in ToT (due to r224938), I'll re-land this patch.
Re-landed in r225097: <http://trac.webkit.org/r225097>.