asm_loong64.s raw

   1  // Copyright 2022 The Go Authors. All rights reserved.
   2  // Use of this source code is governed by a BSD-style
   3  // license that can be found in the LICENSE file.
   4  
   5  #include "textflag.h"
   6  #include "abi_loong64.h"
   7  
   8  // Called by C code generated by cmd/cgo.
   9  // func crosscall2(fn, a unsafe.Pointer, n int32, ctxt uintptr)
  10  // Saves C callee-saved registers and calls cgocallback with three arguments.
  11  // fn is the PC of a func(a unsafe.Pointer) function.
  12  TEXT crosscall2(SB),NOSPLIT|NOFRAME,$0
  13  	/*
  14  	 * We still need to save all callee save register as before, and then
  15  	 * push 3 args for fn (R4, R5, R7), skipping R6.
  16  	 * Also note that at procedure entry in gc world, 8(R29) will be the
  17  	 *  first arg.
  18  	 */
  19  
  20  	ADDV	$(-23*8), R3
  21  	MOVV	R4, (1*8)(R3) // fn unsafe.Pointer
  22  	MOVV	R5, (2*8)(R3) // a unsafe.Pointer
  23  	MOVV	R7, (3*8)(R3) // ctxt uintptr
  24  
  25  	SAVE_R22_TO_R31((4*8))
  26  	SAVE_F24_TO_F31((14*8))
  27  	MOVV	R1, (22*8)(R3)
  28  
  29  	// Initialize Go ABI environment
  30  	JAL	runtime·load_g(SB)
  31  
  32  	JAL	runtime·cgocallback(SB)
  33  
  34  	RESTORE_R22_TO_R31((4*8))
  35  	RESTORE_F24_TO_F31((14*8))
  36  	MOVV	(22*8)(R3), R1
  37  
  38  	ADDV	$(23*8), R3
  39  
  40  	RET
  41