Almost completely eliminates the ifdefs in this file, improving
confidence in the lesser used 32-bit builds.
Backports commit 3a13c3f34ce2058e0c2decc3b0f9f56be24c9400 from qemu
Some of these functions are really quite large. We have a number of
things that ought to be circularly dependent, but we duplicated code
to break that chain for the inlines.
This saved 25% of the code size of one of the translators I examined.