Trim fast elements tail on significant length decreases.

Trim fast elements tail on significant length decreases.

Runtime_RegExpExecMultiple had to be updated because it assumed
setting an array's length to zero still keeps some capacity in the
backing store.

R=ager@chromium.org

Committed: http://code.google.com/p/v8/source/detail?r=8396

[Mads Ager (chromium), 2011-06-23 06:37:04]

LGTM

http://codereview.chromium.org/7237004/diff/1/src/runtime.cc
File src/runtime.cc (right):

http://codereview.chromium.org/7237004/diff/1/src/runtime.cc#newcode3536
src/runtime.cc:3536: if (result_elements.is_null() || result_elements->length()
< 16) {
Is this an unrelated change?

[Mads Ager (chromium), 2011-06-23 08:54:08]

http://codereview.chromium.org/7237004/diff/1/src/runtime.cc
File src/runtime.cc (right):

http://codereview.chromium.org/7237004/diff/1/src/runtime.cc#newcode3536
src/runtime.cc:3536: if (result_elements.is_null() || result_elements->length()
< 16) {
On 2011/06/23 06:37:04, Mads Ager wrote:
> Is this an unrelated change?

Nevermind, just read the change description. :-)