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asm_linux_arm.s
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asm_linux_arm.s
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// 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 "funcdata.h"
//
// System calls for arm, Linux
//
// TODO(kaib): handle error returns
// func Syscall(syscall uintptr, a1, a2, a3 uintptr) (r1, r2, err uintptr);
TEXT ·Syscall(SB),NOSPLIT,$0-28
BL runtime·entersyscall(SB)
MOVW trap+0(FP), R7
MOVW a1+4(FP), R0
MOVW a2+8(FP), R1
MOVW a3+12(FP), R2
MOVW $0, R3
MOVW $0, R4
MOVW $0, R5
SWI $0
MOVW $0xfffff001, R1
CMP R1, R0
BLS ok
MOVW $-1, R1
MOVW R1, r1+16(FP)
MOVW $0, R2
MOVW R2, r2+20(FP)
RSB $0, R0, R0
MOVW R0, err+24(FP)
BL runtime·exitsyscall(SB)
RET
ok:
MOVW R0, r1+16(FP)
MOVW $0, R0
MOVW R0, r2+20(FP)
MOVW R0, err+24(FP)
BL runtime·exitsyscall(SB)
RET
// func Syscall6(trap uintptr, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, err uintptr);
// Actually Syscall5 but the rest of the code expects it to be named Syscall6.
TEXT ·Syscall6(SB),NOSPLIT,$0-40
BL runtime·entersyscall(SB)
MOVW trap+0(FP), R7 // syscall entry
MOVW a1+4(FP), R0
MOVW a2+8(FP), R1
MOVW a3+12(FP), R2
MOVW a4+16(FP), R3
MOVW a5+20(FP), R4
MOVW a6+24(FP), R5
SWI $0
MOVW $0xfffff001, R6
CMP R6, R0
BLS ok6
MOVW $-1, R1
MOVW R1, r1+28(FP)
MOVW $0, R2
MOVW R2, r2+32(FP)
RSB $0, R0, R0
MOVW R0, err+36(FP)
BL runtime·exitsyscall(SB)
RET
ok6:
MOVW R0, r1+28(FP)
MOVW R1, r2+32(FP)
MOVW $0, R0
MOVW R0, err+36(FP)
BL runtime·exitsyscall(SB)
RET
// func RawSyscall6(trap uintptr, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, err uintptr);
// Actually RawSyscall5 but the rest of the code expects it to be named RawSyscall6.
TEXT ·RawSyscall6(SB),NOSPLIT,$0-40
MOVW trap+0(FP), R7 // syscall entry
MOVW a1+4(FP), R0
MOVW a2+8(FP), R1
MOVW a3+12(FP), R2
MOVW a4+16(FP), R3
MOVW a5+20(FP), R4
MOVW a6+24(FP), R5
SWI $0
MOVW $0xfffff001, R6
CMP R6, R0
BLS ok2
MOVW $-1, R1
MOVW R1, r1+28(FP)
MOVW $0, R2
MOVW R2, r2+32(FP)
RSB $0, R0, R0
MOVW R0, err+36(FP)
RET
ok2:
MOVW R0, r1+28(FP)
MOVW R1, r2+32(FP)
MOVW $0, R0
MOVW R0, err+36(FP)
RET
#define SYS__LLSEEK 140 /* from zsysnum_linux_arm.go */
// func seek(fd int, offset int64, whence int) (newoffset int64, errno int)
// Implemented in assembly to avoid allocation when
// taking the address of the return value newoffset.
// Underlying system call is
// llseek(int fd, int offhi, int offlo, int64 *result, int whence)
TEXT ·seek(SB),NOSPLIT,$0-28
BL runtime·entersyscall(SB)
MOVW $SYS__LLSEEK, R7 // syscall entry
MOVW fd+0(FP), R0
MOVW offset_hi+8(FP), R1
MOVW offset_lo+4(FP), R2
MOVW $newoffset_lo+16(FP), R3
MOVW whence+12(FP), R4
SWI $0
MOVW $0xfffff001, R6
CMP R6, R0
BLS okseek
MOVW $0, R1
MOVW R1, newoffset_lo+16(FP)
MOVW R1, newoffset_hi+20(FP)
RSB $0, R0, R0
MOVW R0, err+24(FP)
BL runtime·exitsyscall(SB)
RET
okseek:
// system call filled in newoffset already
MOVW $0, R0
MOVW R0, err+24(FP)
BL runtime·exitsyscall(SB)
RET
// func RawSyscall(trap uintptr, a1, a2, a3 uintptr) (r1, r2, err uintptr);
TEXT ·RawSyscall(SB),NOSPLIT,$0-28
MOVW trap+0(FP), R7 // syscall entry
MOVW a1+4(FP), R0
MOVW a2+8(FP), R1
MOVW a3+12(FP), R2
SWI $0
MOVW $0xfffff001, R1
CMP R1, R0
BLS ok1
MOVW $-1, R1
MOVW R1, r1+16(FP)
MOVW $0, R2
MOVW R2, r2+20(FP)
RSB $0, R0, R0
MOVW R0, err+24(FP)
RET
ok1:
MOVW R0, r1+16(FP)
MOVW $0, R0
MOVW R0, r2+20(FP)
MOVW R0, err+24(FP)
RET