Eliminate Smi check when changing from Smi to Integer32

BUG=
R=verwaest@chromium.org

Review URL: https://chromiumcodereview.appspot.com/22824003

Patch from Weiliang Lin <weiliang.lin2@gmail.com>.

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@16362 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Drop platform-nullos stuff, which was already horribly out-of-date for a long time.

R=verwaest@chromium.org

Review URL: https://codereview.chromium.org/23434004

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@16363 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Fixed HMul::Canonicalize() to support SMI

Same idea for HDiv when the right oeprand is 1

BUG=
R=jkummerow@chromium.org

Review URL: https://codereview.chromium.org/23176002

Patch from Weiliang Lin <weiliang.lin2@gmail.com>.

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@16364 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Introduce SmiValuesAre31Bits and SmiValuesAre32Bits global predicate functions

R=danno@chromium.org

Review URL: https://codereview.chromium.org/22350005

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@16365 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Fix definition of V8_*_C() macros.

Make V8_INT64_C() and V8_UINT64_C() available in 32-bit mode as well,
so we can write readable constants (base 10) instead of having to
obfuscate them using V8_2PART_UINT64_C().

R=svenpanne@chromium.org

Review URL: https://codereview.chromium.org/23557002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@16366 ce2b1a6d-e550-0410-aec6-3dcde31c8c00