(function units): Numerous cycle count change.

(zero_extendqidi2, extendqidi2, zero_extendhidi2): New patterns.
(extendhidi2, zero_extendsidi2, extendsidi2): Likewise.
(zero_extendqisi2, zero_extendqihi2, zero_extendhisi2): Use
andil/andi instead of rlinm/rlwinm.
(zero_extendqihi2): Add condition register variants.
(extendqisi2, extendqihi2): Use extsb for PowerPC.
(adddi3, subdi3, negdi2, ashrdi3): Emulate only if !TARGET_POWERPC64.
(movdf, movdi, movti): New PowerPC64 versions.
(load/store with update): New PowerPC64 patterns.

From-SVN: r7288