liblog: add __attribute__((uninitialized)) to liblog buffers

These buffers are immediately written into with *printf() and are in
the hot path, so do not initialize them.  This saves ~70ns off of each
log message, which is ~14% of the overhead within
__android_log_print() when writing to a no-op logger.

Test: liblog benchmarks
Change-Id: I2b898e72c75b57bc63fee565b49a4e00e377ed1a
1 file changed
tree: 189215c2d924352163cbfdc89b6d88a8ae7b64b0
  1. liblog/
  2. logcat/
  3. logd/
  4. logwrapper/