| // Copyright 2022 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_loong64.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 | |
| MOVV _crosscall2_ptr(SB), R5 | |
| MOVV $crosscall2_trampoline<>(SB), R6 | |
| MOVV R6, (R5) | |
| 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 (R4, R5, R7), skipping R6. | |
| * Also note that at procedure entry in gc world, 8(R29) will be the | |
| * first arg. | |
| */ | |
| ADDV $(-23*8), R3 | |
| MOVV R4, (1*8)(R3) // fn unsafe.Pointer | |
| MOVV R5, (2*8)(R3) // a unsafe.Pointer | |
| MOVV R7, (3*8)(R3) // ctxt uintptr | |
| SAVE_R22_TO_R31((4*8)) | |
| SAVE_F24_TO_F31((14*8)) | |
| MOVV R1, (22*8)(R3) | |
| // Initialize Go ABI environment | |
| JAL runtime路load_g(SB) | |
| JAL runtime路cgocallback(SB) | |
| RESTORE_R22_TO_R31((4*8)) | |
| RESTORE_F24_TO_F31((14*8)) | |
| MOVV (22*8)(R3), R1 | |
| ADDV $(23*8), R3 | |
| RET | |