// s390x uses old_mmap, so the arguments need to be placed into
	// a struct and a pointer to the struct passed to mmap.
	MOVD	R2, addr-48(SP)
	MOVD	R3, n-40(SP)
	MOVD	R4, prot-32(SP)
	MOVD	R5, flags-24(SP)
	MOVD	R6, fd-16(SP)
	MOVD	R7, off-8(SP)

	MOVD	$addr-48(SP), R2
	MOVW	$SYS_mmap, R1
	SYSCALL
	MOVD	$-4095, R3
	CMPUBLT	R2, R3, ok
	NEG	R2
	MOVD	$0, p+32(FP)
	MOVD	R2, err+40(FP)
	RET

		gp21a0      = regInfo{inputs: []regMask{gp, gp | sp | sb}, outputs: []regMask{gp}}
		gp21cxer    = regInfo{inputs: []regMask{gp | sp | sb, gp | sp | sb}, outputs: []regMask{gp}, clobbers: xer}
		gp21xer     = regInfo{inputs: []regMask{gp | sp | sb, gp | sp | sb}, outputs: []regMask{gp, xer}, clobbers: xer}

        assertOrder(X_EQ_Y, "1.final", "1.Final");
        assertOrder(X_EQ_Y, "1.release", "1.RELEASE");
        assertOrder(X_EQ_Y, "1.release", "1.Release");

        assertOrder(X_EQ_Y, "1.sp", "1.SP");
        assertOrder(X_EQ_Y, "1.sp", "1.Sp");

        assertOrder(X_EQ_Y, "1.unknown", "1.UNKNOWN");
        assertOrder(X_EQ_Y, "1.unknown", "1.Unknown");
    }

    @Test

	// Save current m->g0->sched.sp on stack and then set it to SP.
	// Save current sp in m->g0->sched.sp in preparation for
	// switch back to m->curg stack.
	// NOTE: unwindm knows that the saved g->sched.sp is at 8(R29) aka savedsp-16(SP).
	MOVV	m_g0(R12), R19
	MOVV	(g_sched+gobuf_sp)(R19), R13
	MOVV	R13, savedsp-24(SP) // must match frame size
	MOVV	R3, (g_sched+gobuf_sp)(R19)

	// Switch to m->curg stack and call runtime.cgocallbackg.

	if sp != 0 && (sp < gp.stack.lo || gp.stack.hi < sp) {
		print("recover: ", hex(sp), " not in [", hex(gp.stack.lo), ", ", hex(gp.stack.hi), "]\n")
		throw("bad recovery")
	}

	// Make the deferproc for this d return again,
	// this time returning 1. The calling function will
	// jump to the standard return epilogue.
	gp.sched.sp = sp
	gp.sched.pc = pc
	gp.sched.lr = 0

			// Format the sparse map.
			formatSPD := func(sp sparseDatas, sa sparseArray) sparseDatas {
				for i := 0; len(sp) > 0 && i < sa.MaxEntries(); i++ {
					f.formatNumeric(sa.Entry(i).Offset(), sp[0].Offset)
					f.formatNumeric(sa.Entry(i).Length(), sp[0].Length)
					sp = sp[1:]
				}
				if len(sp) > 0 {
					sa.IsExtended()[0] = 1
				}
				return sp
			}
			sp2 := formatSPD(spd, blk.GNU().Sparse())

	gp := gFromSP(mp, c.sp())

	sigprof(c.ip(), c.sp(), c.lr(), gp, mp)
}

func gFromSP(mp *m, sp uintptr) *g {
	if gp := mp.g0; gp != nil && gp.stack.lo < sp && sp < gp.stack.hi {
		return gp
	}
	if gp := mp.gsignal; gp != nil && gp.stack.lo < sp && sp < gp.stack.hi {
		return gp
	}
	if gp := mp.curg; gp != nil && gp.stack.lo < sp && sp < gp.stack.hi {
		return gp
	}

	// Save current m->g0->sched.sp on stack and then set it to SP.
	// Save current sp in m->g0->sched.sp in preparation for
	// switch back to m->curg stack.
	// NOTE: unwindm knows that the saved g->sched.sp is at 4(R13) aka savedsp-12(SP).
	MOVW	m_g0(R8), R3
	MOVW	(g_sched+gobuf_sp)(R3), R4
	MOVW	R4, savedsp-12(SP)	// must match frame size
	MOVW	R13, (g_sched+gobuf_sp)(R3)

	// Switch to m->curg stack and call runtime.cgocallbackg.

	// Save current m->g0->sched.sp on stack and then set it to SP.
	// Save current sp in m->g0->sched.sp in preparation for
	// switch back to m->curg stack.
	// NOTE: unwindm knows that the saved g->sched.sp is at 4(R29) aka savedsp-8(SP).
	MOVW	m_g0(R3), R1
	MOVW	(g_sched+gobuf_sp)(R1), R2
	MOVW	R2, savedsp-12(SP)	// must match frame size
	MOVW	R29, (g_sched+gobuf_sp)(R1)

	// Switch to m->curg stack and call runtime.cgocallbackg.

					// The stack may have moved, which changes SP. Update the local SP variable.
					updateLocalSP(w)
				}

			default:
				panic("bad type for Call")
			}

		case ACallIndirect:
			writeUleb128(w, uint64(p.To.Offset))
			w.WriteByte(0x00) // reserved value
			if hasLocalSP {
				// The stack may have moved, which changes SP. Update the local SP variable.
				updateLocalSP(w)
			}