// 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"

// Set the x_crosscall2_ptr C function pointer variable point to crosscall2.

// It's such a pointer chain: _crosscall2_ptr -> x_crosscall2_ptr -> crosscall2

// Use a local trampoline, to avoid taking the address of a dynamically exported

// function.

TEXT ·set_crosscall2(SB),NOSPLIT,$0-0

MOVL _crosscall2_ptr(SB), AX

MOVL $crosscall2_trampoline<>(SB), BX

MOVL BX, (AX)

RET

TEXT crosscall2_trampoline<>(SB),NOSPLIT,$0-0

JMP crosscall2(SB)

// 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.

TEXT crosscall2(SB),NOSPLIT,$28-16

MOVL BP, 24(SP)

MOVL BX, 20(SP)

MOVL SI, 16(SP)

MOVL DI, 12(SP)

MOVL ctxt+12(FP), AX

MOVL AX, 8(SP)

MOVL a+4(FP), AX

MOVL AX, 4(SP)

MOVL fn+0(FP), AX

MOVL AX, 0(SP)

CALL runtime·cgocallback(SB)

MOVL 12(SP), DI

MOVL 16(SP), SI

MOVL 20(SP), BX

MOVL 24(SP), BP

RET