target-ppc: Special Case of rlwimi Should Use Deposit

The special case of rlwimi where MB <= ME and SH = 31-ME can be implemented
with a single TCG deposit operation.  This replaces the less general case
of SH = MB = 0 and ME = 31.

Signed-off-by: Tom Musta <tommusta@gmail.com>
Suggested-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
target-ppc: Optimize rlwinm MB=0 ME=31

Optimize the special case of rlwinm where MB=0 and ME=31.  This can
be implemented as a 32-bit ROTL.

Signed-off-by: Tom Musta <tommusta@gmail.com>
Suggested-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
target-ppc: Optimize rlwnm MB=0 ME=31

Optimize the special case of rlwnm where MB=0 and ME=31.  This can
be implemented using a ROTL.

Suggested-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Tom Musta <tommusta@gmail.com>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
target-ppc: Clean Up mullw

Eliminate the unecessary ext32s TCG operation and make the multiplication
operation explicitly 32 bit.

Signed-off-by: Tom Musta <tommusta@gmail.com>
Suggested-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
target-ppc: Clean up mullwo

Simplify the implementation of mullwo.  For 64 bit CPUs, the result is
the concatenation of the upper and lower parts of the muls2_i32 operation,
which may be slightly better than deposit.  For 32 bit CPUs, the lower part
of the muls_i32 operation is moved into the target GPR.

Signed-off-by: Tom Musta <tommusta@gmail.com>
Suggested-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
target-ppc: Implement mulldo with TCG

Optimize mulldo by using the muls2_i64 operation rather than a helper.  Eliminate
the obsolete helper code.

Signed-off-by: Tom Musta <tommusta@gmail.com>
Suggested-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Alexander Graf <agraf@suse.de>