Extend JSBuiltinReducer to cover Math.fround as well.

R=bmeurer@chromium.org
TEST=compiler-unittests/JSBuiltinReducerTest.MathFround

Review URL: https://codereview.chromium.org/594183004

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24187 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
[turbofan] ARM64 support for inverted logical ops

Select ARM64 inverted rhs instructions (bic, orn, eon) for cases where the rhs
input is inverted (using e/xor), and add some tests for this. Also, rename xor
to eor in the ARM64 backend.

BUG=
R=bmeurer@chromium.org

Review URL: https://codereview.chromium.org/591383003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24188 ce2b1a6d-e550-0410-aec6-3dcde31c8c00