Get rid of HStringLength.

Use HLoadNamedField to load the string length field instead.

Depends on: https://codereview.chromium.org/21488002

R=svenpanne@chromium.org

Review URL: https://codereview.chromium.org/21499002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@16002 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Revert "Speed-up 'new TypedArray(arrayLike)'."

This reverts commit r15998 for breaking NaCl build.

TBR=bmeurer@chromium.org

Review URL: https://codereview.chromium.org/21503002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@16003 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Pretenure heap number in high promotino mode if a store requires a mutable heap number to be allocated.

BUG=
R=mstarzinger@chromium.org

Review URL: https://codereview.chromium.org/21501002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@16004 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Speed-up 'new TypedArray(arrayLike)'.

Handle specially the cases when the argument is a typed array,
in particular of the same type as the one we create.

Allocate backing store uninitialized in cases when we can guarantee
complete initialization.

R=bmeurer@chromium.org

Committed: https://code.google.com/p/v8/source/detail?r=15998

Review URL: https://codereview.chromium.org/21369002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@16005 ce2b1a6d-e550-0410-aec6-3dcde31c8c00