[PATCH 0/4] Minor performance tuning

[Adam Jackson]

Found these in an old work branch.  The first two are only relevant if
you're using XACE or dtrace, the second two apply unconditionally.
The total series is good for about 13% speedup on x11perf's 10x10
PutImage and ShmPutImage tests, and should be a win across the board.

Alan, I assume the dtrace change is compatible with Solaris'
implementation, I'm just going by the code that the systemtap dtrace
emulation generates.

- ajax