Remove a race between sweepers and the free space skipping code (while iterating new space pointers).

There has been a race between a sweeper setting the next pointer on
free list node and the main thread skipping free space during update of
new space pointers in the heap.

This change removes the free space skipping code.

R=hpayer@chromium.org
BUG=370551
LOG=N

Review URL: https://codereview.chromium.org/285733003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@21306 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Add randomized test generation capability to tools/generate-runtime-tests.py

R=jarin@chromium.org

Review URL: https://codereview.chromium.org/288443005

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@21307 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Introduce a dynamic process pool for the local test driver

The new process pool allows adding jobs after testing has been started. It will also allow to restructure building the job queue (in a follow up CL), so that testing can start instantly while the queue is being built.

Also attempts to clean up the keyboard-interrupt logic. Idea: Only catch keyboard interrupt once per process at the outermost level. Use proper "finally" clauses to clean up everywhere where a keyboard interrupt might occur. Never turn named exceptions into none-exceptions using anonymous "raise".

TEST=python -m unittest pool_unittest
R=jkummerow@chromium.org

Review URL: https://codereview.chromium.org/275093002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@21310 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
A number of small changes:
  - Change ConstantD for +/-zero constants to use the fp_zero register.
  - Use Bfi in DoConstructDouble.
  - Use Tbz for positive dividend check in mod by constant.
  - Optimize some deoptimize checks.
  - Fix a couple of style/consistency issues.

BUG=
R=ulan@chromium.org

Review URL: https://codereview.chromium.org/272183003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@21311 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Merge remote-tracking branch 'upstream/bleeding_edge' into bleeding_edge