| // Copyright 2016 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 |
| MOVD _crosscall2_ptr(SB), R1 |
| MOVD $crosscall2_trampoline<>(SB), R2 |
| MOVD R2, (R1) |
| 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|NOFRAME,$0 |
| // Start with standard C stack frame layout and linkage. |
| |
| // Save R6-R15 in the register save area of the calling function. |
| STMG R6, R15, 48(R15) |
| |
| // Allocate 96 bytes on the stack. |
| MOVD $-96(R15), R15 |
| |
| // Save F8-F15 in our stack frame. |
| FMOVD F8, 32(R15) |
| FMOVD F9, 40(R15) |
| FMOVD F10, 48(R15) |
| FMOVD F11, 56(R15) |
| FMOVD F12, 64(R15) |
| FMOVD F13, 72(R15) |
| FMOVD F14, 80(R15) |
| FMOVD F15, 88(R15) |
| |
| // Initialize Go ABI environment. |
| BL runtime·load_g(SB) |
| |
| MOVD R2, 8(R15) // fn unsafe.Pointer |
| MOVD R3, 16(R15) // a unsafe.Pointer |
| // Skip R4 = n uint32 |
| MOVD R5, 24(R15) // ctxt uintptr |
| BL runtime·cgocallback(SB) |
| |
| FMOVD 32(R15), F8 |
| FMOVD 40(R15), F9 |
| FMOVD 48(R15), F10 |
| FMOVD 56(R15), F11 |
| FMOVD 64(R15), F12 |
| FMOVD 72(R15), F13 |
| FMOVD 80(R15), F14 |
| FMOVD 88(R15), F15 |
| |
| // De-allocate stack frame. |
| MOVD $96(R15), R15 |
| |
| // Restore R6-R15. |
| LMG 48(R15), R6, R15 |
| |
| RET |
| |
