// pointer, though it's harmless to not do this.

#ifdef GOOS_windows

// REGS_HOST_TO_ABI0_STACK is the stack bytes used by
// PUSH_REGS_HOST_TO_ABI0.
#define REGS_HOST_TO_ABI0_STACK (28*8 + 8)

// PUSH_REGS_HOST_TO_ABI0 prepares for transitioning from
// the host ABI to Go ABI0 code. It saves all registers that are
// callee-save in the host ABI and caller-save in Go ABI0 and prepares

// exception record and context pointers.
// DX is the kind of sigtramp function.
// Return value of sigtrampgo is stored in AX.
TEXT sigtramp<>(SB),NOSPLIT,$0-0
	// Switch from the host ABI to the Go ABI.
	PUSH_REGS_HOST_TO_ABI0()

	// Set up ABIInternal environment: cleared X15 and R14.
	// R14 is cleared in case there's a non-zero value in there
	// if called from a non-go thread.
	XORPS	X15, X15
	XORQ	R14, R14

// Saves C callee-saved registers and calls cgocallback with three arguments.
// fn is the PC of a func(a unsafe.Pointer) function.
// This signature is known to SWIG, so we can't change it.
TEXT crosscall2(SB),NOSPLIT,$0-0
	PUSH_REGS_HOST_TO_ABI0()

	// Make room for arguments to cgocallback.
	ADJSP	$0x18
#ifndef GOOS_windows
	MOVQ	DI, 0x0(SP)	/* fn */
	MOVQ	SI, 0x8(SP)	/* arg */
	// Skip n in DX.
	MOVQ	CX, 0x10(SP)	/* ctxt */
#else

	ANDQ	$~15, SP	// alignment for x86_64 ABI
	CALL	AX
	MOVQ	BX, SP
	RET

// Called using C ABI.
TEXT runtime·sigtramp(SB),NOSPLIT|TOPFRAME|NOFRAME,$0
	// Transition from C ABI to Go ABI.
	PUSH_REGS_HOST_TO_ABI0()

	// Set up ABIInternal environment: g in R14, cleared X15.
	get_tls(R12)
	MOVQ	g(R12), R14
	PXOR	X15, X15

	// Reserve space for spill slots.
	NOP	SP		// disable vet stack checking

// a signal is received. It just redirects to the Go function sigtrampgo.
// Called using C ABI.
TEXT runtime·sigtramp(SB),NOSPLIT|TOPFRAME|NOFRAME,$0
	// Transition from C ABI to Go ABI.
	PUSH_REGS_HOST_TO_ABI0()

	// Set up ABIInternal environment: g in R14, cleared X15.
	get_tls(R12)
	MOVQ	g(R12), R14
	PXOR	X15, X15

	// Reserve space for spill slots.
	NOP	SP		// disable vet stack checking

// Note: called with the C calling convention.
TEXT runtime·mstart_stub(SB),NOSPLIT,$0
	// DI points to the m.
	// We are already on m's g0 stack.

	// Transition from C ABI to Go ABI.
	PUSH_REGS_HOST_TO_ABI0()

	// Load g and save to TLS entry.
	// See cmd/link/internal/ld/sym.go:computeTLSOffset.
	MOVQ	m_g0(DI), DX // g
	MOVQ	DX, -8(FS)

	CALL	runtime·mstart(SB)

	POP_REGS_HOST_TO_ABI0()

	ANDQ	$~15, SP     // alignment for x86_64 ABI
	CALL	AX
	MOVQ	BX, SP
	RET

// Called using C ABI.
TEXT runtime·sigtramp(SB),NOSPLIT|TOPFRAME|NOFRAME,$0
	// Transition from C ABI to Go ABI.
	PUSH_REGS_HOST_TO_ABI0()

	// Set up ABIInternal environment: g in R14, cleared X15.
	get_tls(R12)
	MOVQ	g(R12), R14
	PXOR	X15, X15

	// Reserve space for spill slots.
	NOP	SP		// disable vet stack checking

	ANDQ	$~15, SP	// alignment for x86_64 ABI
	CALL	AX
	MOVQ	BX, SP
	RET

// Called using C ABI.
TEXT runtime·sigtramp(SB),NOSPLIT|TOPFRAME|NOFRAME,$0
	// Transition from C ABI to Go ABI.
	PUSH_REGS_HOST_TO_ABI0()

	// Set up ABIInternal environment: g in R14, cleared X15.
	get_tls(R12)
	MOVQ	g(R12), R14
	PXOR	X15, X15

	// Reserve space for spill slots.
	NOP	SP		// disable vet stack checking

	ANDQ	$~15, SP	// alignment for x86_64 ABI
	CALL	AX
	MOVQ	BX, SP
	RET

// Called using C ABI.
TEXT runtime·sigtramp(SB),NOSPLIT|TOPFRAME|NOFRAME,$0
	// Transition from C ABI to Go ABI.
	PUSH_REGS_HOST_TO_ABI0()

	// Set up ABIInternal environment: g in R14, cleared X15.
	get_tls(R12)
	MOVQ	g(R12), R14
	PXOR	X15, X15

	// Reserve space for spill slots.
	NOP	SP		// disable vet stack checking

	MOVQ	g(RARG0), RARG0
	MOVQ	g_m(RARG0), RARG0
	MOVQ	m_p(RARG0), RARG0
	MOVQ	p_raceprocctx(RARG0), RARG0
	MOVQ	RARG0, (RARG1)
	RET

rest:
	// Transition from C ABI to Go ABI.
	PUSH_REGS_HOST_TO_ABI0()
	// Set g = g0.
	get_tls(R12)
	MOVQ	g(R12), R14
	MOVQ	g_m(R14), R13
	MOVQ	m_g0(R13), R15
	CMPQ	R13, R15
	JEQ	noswitch	// branch if already on g0
	MOVQ	R15, g(R12)	// g = m->g0