| // Copyright 2015 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_arm64.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 |
| /* |
| * We still need to save all callee save register as before, and then |
| * push 3 args for fn (R0, R1, R3), skipping R2. |
| * Also note that at procedure entry in gc world, 8(RSP) will be the |
| * first arg. |
| */ |
| SUB $(8*24), RSP |
| STP (R0, R1), (8*1)(RSP) |
| MOVD R3, (8*3)(RSP) |
| |
| SAVE_R19_TO_R28(8*4) |
| SAVE_F8_TO_F15(8*14) |
| STP (R29, R30), (8*22)(RSP) |
| |
| |
| // Initialize Go ABI environment |
| BL runtime·load_g(SB) |
| BL runtime·cgocallback(SB) |
| |
| RESTORE_R19_TO_R28(8*4) |
| RESTORE_F8_TO_F15(8*14) |
| LDP (8*22)(RSP), (R29, R30) |
| |
| ADD $(8*24), RSP |
| RET |
