MOVQ	DX, (g_sched+gobuf_ctxt)(DI)

	MOVQ	m_g0(BX), SI  // SI = m.g0
	CMPQ	DI, SI
	JNE	3(PC)
	CALL	runtime·badmorestackg0(SB)
	CALL	runtime·abort(SB)

	// Cannot grow signal stack (m->gsignal).
	MOVQ	m_gsignal(BX), SI
	CMPQ	DI, SI
	JNE	3(PC)
	CALL	runtime·badmorestackgsignal(SB)
	CALL	runtime·abort(SB)

	// Called from f.
	// Set m->morebuf to f's caller.

	assistG := deductAssistCredit(size)

	// Set mp.mallocing to keep from being preempted by GC.
	mp := acquirem()
	if mp.mallocing != 0 {
		throw("malloc deadlock")
	}
	if mp.gsignal == getg() {
		throw("malloc during signal")
	}
	mp.mallocing = 1

	shouldhelpgc := false
	dataSize := userSize
	c := getMCache(mp)
	if c == nil {