Rather than allow arbitrary shift+trunc, only concern ourselves
with low and high parts. This is all that was being used anyway.
Backports commit 609ad70562793937257c89d07bf7c1370b9fc9aa from qemu
Rather reserving space in the op stream for optimization,
let the optimizer add ops as necessary.
Backports commit a4ce099a7a4b4734c372f6bf28f3362e370f23c1 from qemu
With the linked list scheme we need not leave nops in the stream
that we need to process later.
Backports commit 0c627cdca20155753a536c51385abb73941a59a0 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.
