Hi,

The attached SH patch converts sequences such as:
	movt	r2
	movt	r13
into:
	movt	r2
	mov	r2,r13

This shortens the live range of the T bit register and is better for
parallel execution.  It doesn't happen often, but it's easy to avoid it.

Unfortunately I had to do this manually because cprop_hardreg gets in
the way here.  If done as a peephole2, cprop_hardreg then
unconditionally just converts it back, because it thinks that all reg
copies are equal in some way.

Tested on sh-elf with
make -k check RUNTESTFLAGS="--target_board=sh-sim
\{-m2/-ml,-m2/-mb,-m2a/-mb,-m4/-ml,-m4/-mb,-m4a/-ml,-m4a/-mb}"

Committed as r228386.

Cheers,
Oleg

gcc/ChangeLog:
	* config/sh/sh.md: Add new unnamed split pattern to handle
	movt-movt sequences.