github.com/likebike/go--@v0.0.0-20190911215757-0bd925d16e96/go/src/syscall/asm_plan9_386.s (about)

     1  // Copyright 2009 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 "funcdata.h"
     7  
     8  //
     9  // System call support for 386, Plan 9
    10  //
    11  
    12  //func Syscall(trap, a1, a2, a3 uintptr) (r1, r2 uintptr, err string)
    13  //func Syscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err string)
    14  //func RawSyscall(trap, a1, a2, a3 uintptr) (r1, r2, err uintptr)
    15  //func RawSyscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, err uintptr)
    16  
    17  // Trap # in AX, args on stack above caller pc.
    18  TEXT	·Syscall(SB),NOSPLIT,$0-32
    19  	CALL	runtime·entersyscall(SB)
    20  	MOVL	trap+0(FP), AX	// syscall entry
    21  	// slide args down on top of system call number
    22  	LEAL	a1+4(FP), SI
    23  	LEAL	trap+0(FP), DI
    24  	CLD
    25  	MOVSL
    26  	MOVSL
    27  	MOVSL
    28  	INT	$64
    29  	MOVL	AX, r1+16(FP)
    30  	MOVL	$0, r2+20(FP)
    31  	CMPL	AX, $-1
    32  	JNE	ok3
    33  
    34  	SUBL	$8, SP
    35  	CALL	runtime·errstr(SB)
    36  	MOVL	SP, SI
    37  	ADDL	$8, SP
    38  	JMP	copyresult3
    39  	
    40  ok3:
    41  	LEAL	·emptystring(SB), SI
    42  	
    43  copyresult3:
    44  	LEAL	err+24(FP), DI
    45  
    46  	CLD
    47  	MOVSL
    48  	MOVSL
    49  
    50  	CALL	runtime·exitsyscall(SB)
    51  	RET
    52  
    53  TEXT	·Syscall6(SB),NOSPLIT,$0-44
    54  	CALL	runtime·entersyscall(SB)
    55  	MOVL	trap+0(FP), AX	// syscall entry
    56  	// slide args down on top of system call number
    57  	LEAL	a1+4(FP), SI
    58  	LEAL	trap+0(FP), DI
    59  	CLD
    60  	MOVSL
    61  	MOVSL
    62  	MOVSL
    63  	MOVSL
    64  	MOVSL
    65  	MOVSL
    66  	INT	$64
    67  	MOVL	AX, r1+28(FP)
    68  	MOVL	$0, r2+32(FP)
    69  	CMPL	AX, $-1
    70  	JNE	ok4
    71  	
    72  	SUBL	$8, SP
    73  	CALL	runtime·errstr(SB)
    74  	MOVL	SP, SI
    75  	ADDL	$8, SP
    76  	JMP	copyresult4
    77  	
    78  ok4:
    79  	LEAL	·emptystring(SB), SI
    80  	
    81  copyresult4:
    82  	LEAL	err+36(FP), DI
    83  
    84  	CLD
    85  	MOVSL
    86  	MOVSL
    87  
    88  	CALL	runtime·exitsyscall(SB)
    89  	RET
    90  
    91  TEXT ·RawSyscall(SB),NOSPLIT,$0-28
    92  	MOVL	trap+0(FP), AX	// syscall entry
    93  	// slide args down on top of system call number
    94  	LEAL	a1+4(FP), SI
    95  	LEAL	trap+0(FP), DI
    96  	CLD
    97  	MOVSL
    98  	MOVSL
    99  	MOVSL
   100  	INT	$64
   101  	MOVL	AX, r1+16(FP)
   102  	MOVL	AX, r2+20(FP)
   103  	MOVL	AX, err+24(FP)
   104  	RET
   105  
   106  TEXT	·RawSyscall6(SB),NOSPLIT,$0-40
   107  	MOVL	trap+0(FP), AX	// syscall entry
   108  	// slide args down on top of system call number
   109  	LEAL	a1+4(FP), SI
   110  	LEAL	trap+0(FP), DI
   111  	CLD
   112  	MOVSL
   113  	MOVSL
   114  	MOVSL
   115  	MOVSL
   116  	MOVSL
   117  	MOVSL
   118  	INT	$64
   119  	MOVL	AX, r1+28(FP)
   120  	MOVL	AX, r2+32(FP)
   121  	MOVL	AX, err+36(FP)
   122  	RET
   123  
   124  #define SYS_SEEK 39	/* from zsysnum_plan9_386.go */
   125  
   126  //func seek(placeholder uintptr, fd int, offset int64, whence int) (newoffset int64, err string)
   127  TEXT ·seek(SB),NOSPLIT,$0-36
   128  	LEAL	newoffset+20(FP), AX
   129  	MOVL	AX, placeholder+0(FP)
   130  	
   131  	MOVL	$SYS_SEEK, AX	// syscall entry
   132  	INT	$64
   133  	
   134  	CMPL	AX, $-1
   135  	JNE	ok6
   136  	MOVL	AX, newoffset_lo+20(FP)
   137  	MOVL	AX, newoffset_hi+24(FP)
   138  	
   139  	SUBL	$8, SP
   140  	CALL	syscall·errstr(SB)
   141  	MOVL	SP, SI
   142  	ADDL	$8, SP	
   143  	JMP	copyresult6
   144  	
   145  ok6:
   146  	LEAL	·emptystring(SB), SI
   147  	
   148  copyresult6:
   149  	LEAL	err+28(FP), DI
   150  
   151  	CLD
   152  	MOVSL
   153  	MOVSL
   154  	RET