- Don't reverse bitfields; do use ego (41f3bf7).
- Use MACHOPT_F=-m2 (3dae9e4).
- Remove old trap.s (26de4c1).
At this commit, one can build qemuppc with mcg by editing the root
build.lua to uncomment "qemuppc" in "vars.plats". If one also
uncomments "qemuppc" from "vars.plats_with_tests", then mcg fails to
build the tests. If one uses ncg (by editing plat/qemuppc/descr to
change "mcg" to "ncg"), then the tests pass.
corresponding invocation in the ncg table so the same helpers can be used for
both mcg and ncg. Add a new IR opcode, FARJUMP, which jumps to a helper
function but saves volatile registers.