1// Copyright 2016 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
7// Called by C code generated by cmd/cgo.
8// func crosscall2(fn, a unsafe.Pointer, n int32, ctxt uintptr)
9// Saves C callee-saved registers and calls cgocallback with three arguments.
10// fn is the PC of a func(a unsafe.Pointer) function.
11TEXT crosscall2(SB), NOSPLIT|NOFRAME, $0
12 // Start with standard C stack frame layout and linkage.
13
14 // Save R6-R15 in the register save area of the calling function.
15 STMG R6, R15, 48(R15)
16
17 // Allocate 96 bytes on the stack.
18 MOVD $-96(R15), R15
19
20 // Save F8-F15 in our stack frame.
21 FMOVD F8, 32(R15)
22 FMOVD F9, 40(R15)
23 FMOVD F10, 48(R15)
24 FMOVD F11, 56(R15)
25 FMOVD F12, 64(R15)
26 FMOVD F13, 72(R15)
27 FMOVD F14, 80(R15)
28 FMOVD F15, 88(R15)
29
30 MOVD R2, 8(R15) // fn unsafe.Pointer
31 MOVD R3, 16(R15) // a unsafe.Pointer
32
33 // Skip R4 = n uint32
34 MOVD R5, 24(R15) // ctxt uintptr
35 BL runtime·cgocallback(SB)
36
37 FMOVD 32(R15), F8
38 FMOVD 40(R15), F9
39 FMOVD 48(R15), F10
40 FMOVD 56(R15), F11
41 FMOVD 64(R15), F12
42 FMOVD 72(R15), F13
43 FMOVD 80(R15), F14
44 FMOVD 88(R15), F15
45
46 // De-allocate stack frame.
47 MOVD $96(R15), R15
48
49 // Restore R6-R15.
50 LMG 48(R15), R6, R15
51
52 RET