// Store the original signal mask for use by minit.
	mp.sigmask = sigmask

	// Install TLS on some platforms (previously setg
	// would do this if necessary).
	osSetupTLS(mp)

	// Install g (= m->g0) and set the stack bounds
	// to match the current stack.
	setg(mp.g0)
	sp := getcallersp()
	callbackUpdateSystemStack(mp, sp, signal)

	// Should mark we are already in Go now.

		x15        = buildReg("X15")
		gpsp       = gp | buildReg("SP")
		gpspsb     = gpsp | buildReg("SB")
		gpspsbg    = gpspsb | g
		callerSave = gp | fp | g // runtime.setg (and anything calling it) may clobber g
	)
	// Common slices of register masks
	var (
		gponly = []regMask{gp}
		fponly = []regMask{fp}
	)

	// Common regInfo
	var (