* src/vm/jit/s390/emit.c,

* src/vm/jit/s390/emit.c,
src/vm/jit/s390/md-abi.h,
src/vm/jit/s390/md.c,
src/vm/jit/s390/emit.h,
src/vm/jit/s390/codegen.c,
src/vm/jit/s390/machine-instr.h,
src/vm/jit/s390/codegen.h,
src/vm/jit/s390/arch.h,
src/vm/jit/s390/md-asm.h,
src/vm/jit/s390/disass.c,
src/vm/jit/s390/patcher.c,
src/vm/jit/s390/asmpart.S,
src/vm/jit/s390/md-abi.c: Adapted S390 port to changes from branches/twisti (hardware exceptions, emit_branch, abi_registers_*), jctest works again. Cleaned up almost all dead x86_64 code.