Fix a bug in the register allocator around pair allocation.

We may get hints that do not work with the current implementation
of register pairs, which forces the allocation of (low + 1)
for the high register. For example, if the hint is EBX, we will
allocate ESP for the high register.


(cherry picked from commit f29758111e71a7d14f3e52d78773561a5d59961f)

Change-Id: Ib395e36616017a87d3055218d72417f4e9ff6501
4 files changed