[r21671]

[r21669]

Only skip Convs within the same register class when trying to create dest AM (is this still necessary at all?).

[r21668]

[r21666]

[r21665]

[r21664]

[r21657]

[r21655]

[r21653]

[r21652]

[r21650]

[r21648]

[r21647]

[r21646]

[r21645]

[r21644]

[r21643]

[r21641]

[r21640]

[r21639]

[r21638]

[r21637]

[r21636]

Partially undo r20786:  Emit ret $0 especially when its BB is only reached by a fallthrough, because this means its predecessor ends with a conditional jump.  According to the AMD Optimization guides, conditional jump directly followed by ret should be avoided.

[r21632]

[r21619]

[r21561]

[r21560]

[r21558]

[r21557]

[r21556]

[r21555]

[r21554]

[r21553]

[r21552]

[r21483]

[r21482]

[r21477]

purposes, call it only if a node is really replaced.

[r21475]

[r21474]

[r21469]