github.com/lovishpuri/go-40569/src@v0.0.0-20230519171745-f8623e7c56cf/runtime/cgo/asm_mipsx.s (about)

     1  // Copyright 2016 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  //go:build mips || mipsle
     6  
     7  #include "textflag.h"
     8  
     9  // Set the x_crosscall2_ptr C function pointer variable point to crosscall2.
    10  // It's such a pointer chain: _crosscall2_ptr -> x_crosscall2_ptr -> crosscall2
    11  TEXT ·set_crosscall2(SB),NOSPLIT,$0-0
    12  	MOVW	_crosscall2_ptr(SB), R5
    13  	MOVW	$crosscall2(SB), R6
    14  	MOVW	R6, (R5)
    15  	RET
    16  
    17  // Called by C code generated by cmd/cgo.
    18  // func crosscall2(fn, a unsafe.Pointer, n int32, ctxt uintptr)
    19  // Saves C callee-saved registers and calls cgocallback with three arguments.
    20  // fn is the PC of a func(a unsafe.Pointer) function.
    21  TEXT crosscall2(SB),NOSPLIT|NOFRAME,$0
    22  	/*
    23  	 * We still need to save all callee save register as before, and then
    24  	 *  push 3 args for fn (R4, R5, R7), skipping R6.
    25  	 * Also note that at procedure entry in gc world, 4(R29) will be the
    26  	 *  first arg.
    27  	 */
    28  
    29  	// Space for 9 caller-saved GPR + LR + 6 caller-saved FPR.
    30  	// O32 ABI allows us to smash 16 bytes argument area of caller frame.
    31  #ifndef GOMIPS_softfloat
    32  	SUBU	$(4*14+8*6-16), R29
    33  #else
    34  	SUBU	$(4*14-16), R29	// For soft-float, no FPR.
    35  #endif
    36  	MOVW	R4, (4*1)(R29)	// fn unsafe.Pointer
    37  	MOVW	R5, (4*2)(R29)	// a unsafe.Pointer
    38  	MOVW	R7, (4*3)(R29)	// ctxt uintptr
    39  	MOVW	R16, (4*4)(R29)
    40  	MOVW	R17, (4*5)(R29)
    41  	MOVW	R18, (4*6)(R29)
    42  	MOVW	R19, (4*7)(R29)
    43  	MOVW	R20, (4*8)(R29)
    44  	MOVW	R21, (4*9)(R29)
    45  	MOVW	R22, (4*10)(R29)
    46  	MOVW	R23, (4*11)(R29)
    47  	MOVW	g, (4*12)(R29)
    48  	MOVW	R31, (4*13)(R29)
    49  #ifndef GOMIPS_softfloat
    50  	MOVD	F20, (4*14)(R29)
    51  	MOVD	F22, (4*14+8*1)(R29)
    52  	MOVD	F24, (4*14+8*2)(R29)
    53  	MOVD	F26, (4*14+8*3)(R29)
    54  	MOVD	F28, (4*14+8*4)(R29)
    55  	MOVD	F30, (4*14+8*5)(R29)
    56  #endif
    57  	JAL	runtime·load_g(SB)
    58  
    59  	JAL	runtime·cgocallback(SB)
    60  
    61  	MOVW	(4*4)(R29), R16
    62  	MOVW	(4*5)(R29), R17
    63  	MOVW	(4*6)(R29), R18
    64  	MOVW	(4*7)(R29), R19
    65  	MOVW	(4*8)(R29), R20
    66  	MOVW	(4*9)(R29), R21
    67  	MOVW	(4*10)(R29), R22
    68  	MOVW	(4*11)(R29), R23
    69  	MOVW	(4*12)(R29), g
    70  	MOVW	(4*13)(R29), R31
    71  #ifndef GOMIPS_softfloat
    72  	MOVD	(4*14)(R29), F20
    73  	MOVD	(4*14+8*1)(R29), F22
    74  	MOVD	(4*14+8*2)(R29), F24
    75  	MOVD	(4*14+8*3)(R29), F26
    76  	MOVD	(4*14+8*4)(R29), F28
    77  	MOVD	(4*14+8*5)(R29), F30
    78  
    79  	ADDU	$(4*14+8*6-16), R29
    80  #else
    81  	ADDU	$(4*14-16), R29
    82  #endif
    83  	RET