MIPS64: Fix simulator arguments handling on generated code entry.

Removed workaround for this issue.

TEST=mjsunit, cctest on sim64
BUG=
R=paul.lind@imgtec.com

Review URL: https://codereview.chromium.org/695933002

Cr-Commit-Position: refs/heads/master@{#25043}
git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@25043 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Revert "Skip the CallFunctionStub when the callee function can be statically determined."

This reverts commit 9845dfadd2ad4a83fa00bf43e0c2791ccf7eacad (r25042) for failing tests.

TBR=titzer@chromium.org
BUG=

Review URL: https://codereview.chromium.org/693103004

Cr-Commit-Position: refs/heads/master@{#25044}
git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@25044 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
[turbofan] Avoid unnecessary (u)int32<->float64 changes in simplified lowering.

BUG=
R=bmeurer@chromium.org, titzer@chromium.org

Review URL: https://codereview.chromium.org/683873002

Cr-Commit-Position: refs/heads/master@{#25045}
git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@25045 ce2b1a6d-e550-0410-aec6-3dcde31c8c00