asm_arm64.s RawHistoryFolder

1// Copyright 2015 The Go Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style
3// license that can be found in the LICENSE file.
4
5#include "textflag.h"
6#include "abi_arm64.h"
7
8// Called by C code generated by cmd/cgo.
9// func crosscall2(fn, a unsafe.Pointer, n int32, ctxt uintptr)
10// Saves C callee-saved registers and calls cgocallback with three arguments.
11// fn is the PC of a func(a unsafe.Pointer) function.
12TEXT crosscall2(SB), NOSPLIT|NOFRAME, $0
13/*
14 * We still need to save all callee save register as before, and then
15 *  push 3 args for fn (R0, R1, R3), skipping R2.
16 * Also note that at procedure entry in gc world, 8(RSP) will be the
17 *  first arg.
18 */
19	SUB  $(8*24), RSP
20	STP  (R0, R1), (8*1)(RSP)
21	MOVD R3, (8*3)(RSP)
22
23	SAVE_R19_TO_R28(8*4)
24	SAVE_F8_TO_F15(8*14)
25	STP (R29, R30), (8*22)(RSP)
26
27	// Initialize Go ABI environment
28	BL runtime·cgocallback(SB)
29
30	RESTORE_R19_TO_R28(8*4)
31	RESTORE_F8_TO_F15(8*14)
32	LDP (8*22)(RSP), (R29, R30)
33
34	ADD $(8*24), RSP
35	RET