// Someday the convention will be D is always cleared.
	CLD

	CALL	runtime·stackcheck(SB)	// clobbers AX,CX
	CALL	runtime·mstart(SB)

	RET

// uint32 tstart_stdcall(M *newm);
TEXT runtime·tstart_stdcall(SB),NOSPLIT,$0
	MOVL	newm+0(FP), BX

	PUSHL	BX
	CALL	tstart<>(SB)
	POPL	BX

	// Adjust stack for stdcall to return properly.

	BL	runtime·cgocallback(SB)

	// Get callback result.
	MOVD	$cbargs-(18*8+callbackArgs__size)(SP), R13
	MOVD	callbackArgs_result(R13), R0

	RESTORE_R19_TO_R28(8*9)

	RET

// uint32 tstart_stdcall(M *newm);
TEXT runtime·tstart_stdcall(SB),NOSPLIT,$96-0
	SAVE_R19_TO_R28(8*3)

	MOVD	m_g0(R0), g
	MOVD	R0, g_m(g)
	BL	runtime·save_g(SB)

	// Set up stack guards for OS stack.
	MOVD	RSP, R0

	ADD	$(16 + callbackArgs__size), R13	// free locals
	MOVM.IA.W (R13), [R4-R11, R12]	// pop {r4-r11, lr=>r12}
	ADD	$(4*4), R13	// skip r0-r3
	B	(R12)	// return

// uint32 tstart_stdcall(M *newm);
TEXT runtime·tstart_stdcall(SB),NOSPLIT|NOFRAME,$0
	MOVM.DB.W [R4-R11, R14], (R13)		// push {r4-r11, lr}

	MOVW	m_g0(R0), g
	MOVW	R0, g_m(g)
	BL	runtime·save_g(SB)

	// Get callback result.
	MOVQ	(24+callbackArgs_result)(SP), AX
	ADDQ	$(24+callbackArgs__size), SP

	POP_REGS_HOST_TO_ABI0()

	// The return value was placed in AX above.
	RET

// uint32 tstart_stdcall(M *newm);
TEXT runtime·tstart_stdcall(SB),NOSPLIT|NOFRAME,$0
	// Switch from the host ABI to the Go ABI.
	PUSH_REGS_HOST_TO_ABI0()

	// CX contains first arg newm
	MOVQ	m_g0(CX), DX		// g

	winmmdll            = [...]uint16{'w', 'i', 'n', 'm', 'm', '.', 'd', 'l', 'l', 0}
)

// Function to be called by windows CreateThread
// to start new os thread.
func tstart_stdcall(newm *m)

// Init-time helper
func wintls()

type mOS struct {
	threadLock mutex   // protects "thread" and prevents closing
	thread     uintptr // thread handle