| // 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 路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,$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路cgocallback(SB) | |
| ADJSP $-0x18 | |
| POP_REGS_HOST_TO_ABI0() | |
| RET | |