| // 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" |
| #include "abi_amd64.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 |
| MOVQ _crosscall2_ptr(SB), AX |
| MOVQ $crosscall2_trampoline<>(SB), BX |
| MOVQ 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. |
| // This signature is known to SWIG, so we can't change it. |
| TEXT crosscall2(SB),NOSPLIT|NOFRAME,$0-0 |
| PUSH_REGS_HOST_TO_ABI0() |
| |
| // Make room for arguments to cgocallback. |
| ADJSP $0x18 |
| #ifndef GOOS_windows |
| MOVQ DI, 0x0(SP) /* fn */ |
| MOVQ SI, 0x8(SP) /* arg */ |
| // Skip n in DX. |
| MOVQ CX, 0x10(SP) /* ctxt */ |
| #else |
| MOVQ CX, 0x0(SP) /* fn */ |
| MOVQ DX, 0x8(SP) /* arg */ |
| // Skip n in R8. |
| MOVQ R9, 0x10(SP) /* ctxt */ |
| #endif |
| |
| CALL runtime·cgocallback(SB) |
| |
| ADJSP $-0x18 |
| POP_REGS_HOST_TO_ABI0() |
| RET |
