// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

#include "textflag.h"
#include "abi_amd64.h"

// Called by C code generated by cmd/cgo.
// func crosscall2(fn, a unsafe.Pointer, n int32, ctxt uintptr)
// 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
	MOVQ CX, 0x0(SP) // fn
	MOVQ DX, 0x8(SP) // arg

	// Skip n in R8.
	MOVQ R9, 0x10(SP) // ctxt

#endif

	CALL runtime·cgocallback(SB)

	ADJSP $-0x18
	POP_REGS_HOST_TO_ABI0()
	RET