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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.
//
// System calls and other sys.stuff for arm, Linux
//
#include "zasm_GOOS_GOARCH.h"
#include "../../cmd/ld/textflag.h"
// for EABI, as we don't support OABI
#define SYS_BASE 0x0
#define SYS_exit (SYS_BASE + 1)
#define SYS_read (SYS_BASE + 3)
#define SYS_write (SYS_BASE + 4)
#define SYS_open (SYS_BASE + 5)
#define SYS_close (SYS_BASE + 6)
#define SYS_gettimeofday (SYS_BASE + 78)
#define SYS_clone (SYS_BASE + 120)
#define SYS_rt_sigreturn (SYS_BASE + 173)
#define SYS_rt_sigaction (SYS_BASE + 174)
#define SYS_rt_sigprocmask (SYS_BASE + 175)
#define SYS_sigaltstack (SYS_BASE + 186)
#define SYS_mmap2 (SYS_BASE + 192)
#define SYS_futex (SYS_BASE + 240)
#define SYS_exit_group (SYS_BASE + 248)
#define SYS_munmap (SYS_BASE + 91)
#define SYS_madvise (SYS_BASE + 220)
#define SYS_setitimer (SYS_BASE + 104)
#define SYS_mincore (SYS_BASE + 219)
#define SYS_gettid (SYS_BASE + 224)
#define SYS_tkill (SYS_BASE + 238)
#define SYS_sched_yield (SYS_BASE + 158)
#define SYS_select (SYS_BASE + 142) // newselect
#define SYS_ugetrlimit (SYS_BASE + 191)
#define SYS_sched_getaffinity (SYS_BASE + 242)
#define SYS_clock_gettime (SYS_BASE + 263)
#define SYS_epoll_create (SYS_BASE + 250)
#define SYS_epoll_ctl (SYS_BASE + 251)
#define SYS_epoll_wait (SYS_BASE + 252)
#define SYS_epoll_create1 (SYS_BASE + 357)
#define SYS_fcntl (SYS_BASE + 55)
#define ARM_BASE (SYS_BASE + 0x0f0000)
TEXT runtime·open(SB),NOSPLIT,$0
MOVW 0(FP), R0
MOVW 4(FP), R1
MOVW 8(FP), R2
MOVW $SYS_open, R7
SWI $0
RET
TEXT runtime·close(SB),NOSPLIT,$0
MOVW 0(FP), R0
MOVW $SYS_close, R7
SWI $0
RET
TEXT runtime·write(SB),NOSPLIT,$0
MOVW 0(FP), R0
MOVW 4(FP), R1
MOVW 8(FP), R2
MOVW $SYS_write, R7
SWI $0
RET
TEXT runtime·read(SB),NOSPLIT,$0
MOVW 0(FP), R0
MOVW 4(FP), R1
MOVW 8(FP), R2
MOVW $SYS_read, R7
SWI $0
RET
TEXT runtime·getrlimit(SB),NOSPLIT,$0
MOVW 0(FP), R0
MOVW 4(FP), R1
MOVW $SYS_ugetrlimit, R7
SWI $0
RET
TEXT runtime·exit(SB),NOSPLIT,$-4
MOVW 0(FP), R0
MOVW $SYS_exit_group, R7
SWI $0
MOVW $1234, R0
MOVW $1002, R1
MOVW R0, (R1) // fail hard
TEXT runtime·exit1(SB),NOSPLIT,$-4
MOVW 0(FP), R0
MOVW $SYS_exit, R7
SWI $0
MOVW $1234, R0
MOVW $1003, R1
MOVW R0, (R1) // fail hard
TEXT runtime·raise(SB),NOSPLIT,$-4
MOVW $SYS_gettid, R7
SWI $0
// arg 1 tid already in R0 from gettid
MOVW sig+0(FP), R1 // arg 2 - signal
MOVW $SYS_tkill, R7
SWI $0
RET
TEXT runtime·mmap(SB),NOSPLIT,$0
MOVW 0(FP), R0
MOVW 4(FP), R1
MOVW 8(FP), R2
MOVW 12(FP), R3
MOVW 16(FP), R4
MOVW 20(FP), R5
MOVW $SYS_mmap2, R7
SWI $0
MOVW $0xfffff001, R6
CMP R6, R0
RSB.HI $0, R0
RET
TEXT runtime·munmap(SB),NOSPLIT,$0
MOVW 0(FP), R0
MOVW 4(FP), R1
MOVW $SYS_munmap, R7
SWI $0
MOVW $0xfffff001, R6
CMP R6, R0
MOVW.HI $0, R8 // crash on syscall failure
MOVW.HI R8, (R8)
RET
TEXT runtime·madvise(SB),NOSPLIT,$0
MOVW 0(FP), R0
MOVW 4(FP), R1
MOVW 8(FP), R2
MOVW $SYS_madvise, R7
SWI $0
// ignore failure - maybe pages are locked
RET
TEXT runtime·setitimer(SB),NOSPLIT,$0
MOVW 0(FP), R0
MOVW 4(FP), R1
MOVW 8(FP), R2
MOVW $SYS_setitimer, R7
SWI $0
RET
TEXT runtime·mincore(SB),NOSPLIT,$0
MOVW 0(FP), R0
MOVW 4(FP), R1
MOVW 8(FP), R2
MOVW $SYS_mincore, R7
SWI $0
RET
TEXT time·now(SB), NOSPLIT, $32
MOVW $0, R0 // CLOCK_REALTIME
MOVW $8(R13), R1 // timespec
MOVW $SYS_clock_gettime, R7
SWI $0
MOVW 8(R13), R0 // sec
MOVW 12(R13), R2 // nsec
MOVW R0, 0(FP)
MOVW $0, R1
MOVW R1, 4(FP)
MOVW R2, 8(FP)
RET
// int64 nanotime(void) so really
// void nanotime(int64 *nsec)
TEXT runtime·nanotime(SB),NOSPLIT,$32
MOVW $0, R0 // CLOCK_REALTIME
MOVW $8(R13), R1 // timespec
MOVW $SYS_clock_gettime, R7
SWI $0
MOVW 8(R13), R0 // sec
MOVW 12(R13), R2 // nsec
MOVW $1000000000, R3
MULLU R0, R3, (R1, R0)
MOVW $0, R4
ADD.S R2, R0
ADC R4, R1
MOVW 0(FP), R3
MOVW R0, 0(R3)
MOVW R1, 4(R3)
RET
// int32 futex(int32 *uaddr, int32 op, int32 val,
// struct timespec *timeout, int32 *uaddr2, int32 val2);
TEXT runtime·futex(SB),NOSPLIT,$0
MOVW 4(SP), R0
MOVW 8(SP), R1
MOVW 12(SP), R2
MOVW 16(SP), R3
MOVW 20(SP), R4
MOVW 24(SP), R5
MOVW $SYS_futex, R7
SWI $0
RET
// int32 clone(int32 flags, void *stack, M *mp, G *gp, void (*fn)(void));
TEXT runtime·clone(SB),NOSPLIT,$0
MOVW flags+0(FP), R0
MOVW stack+4(FP), R1
MOVW $0, R2 // parent tid ptr
MOVW $0, R3 // tls_val
MOVW $0, R4 // child tid ptr
MOVW $0, R5
// Copy mp, gp, fn off parent stack for use by child.
// TODO(kaib): figure out which registers are clobbered by clone and avoid stack copying
MOVW $-16(R1), R1
MOVW mm+8(FP), R6
MOVW R6, 0(R1)
MOVW gg+12(FP), R6
MOVW R6, 4(R1)
MOVW fn+16(FP), R6
MOVW R6, 8(R1)
MOVW $1234, R6
MOVW R6, 12(R1)
MOVW $SYS_clone, R7
SWI $0
// In parent, return.
CMP $0, R0
BEQ 2(PC)
RET
// Paranoia: check that SP is as we expect. Use R13 to avoid linker 'fixup'
MOVW 12(R13), R0
MOVW $1234, R1
CMP R0, R1
BEQ 2(PC)
BL runtime·abort(SB)
MOVW 0(R13), m
MOVW 4(R13), g
// paranoia; check they are not nil
MOVW 0(m), R0
MOVW 0(g), R0
BL runtime·emptyfunc(SB) // fault if stack check is wrong
// Initialize m->procid to Linux tid
MOVW $SYS_gettid, R7
SWI $0
MOVW R0, m_procid(m)
// Call fn
MOVW 8(R13), R0
MOVW $16(R13), R13
BL (R0)
MOVW $0, R0
MOVW R0, 4(R13)
BL runtime·exit1(SB)
// It shouldn't return
MOVW $1234, R0
MOVW $1005, R1
MOVW R0, (R1)
TEXT runtime·sigaltstack(SB),NOSPLIT,$0
MOVW 0(FP), R0
MOVW 4(FP), R1
MOVW $SYS_sigaltstack, R7
SWI $0
MOVW $0xfffff001, R6
CMP R6, R0
MOVW.HI $0, R8 // crash on syscall failure
MOVW.HI R8, (R8)
RET
TEXT runtime·sigtramp(SB),NOSPLIT,$24
// this might be called in external code context,
// where g and m are not set.
// first save R0, because runtime·load_gm will clobber it
MOVW R0, 4(R13)
MOVB runtime·iscgo(SB), R0
CMP $0, R0
BL.NE runtime·load_gm(SB)
CMP $0, m
BNE 4(PC)
// signal number is already prepared in 4(R13)
MOVW $runtime·badsignal(SB), R11
BL (R11)
RET
// save g
MOVW g, R3
MOVW g, 20(R13)
// g = m->gsignal
MOVW m_gsignal(m), g
// copy arguments for call to sighandler
// R0 is already saved above
MOVW R1, 8(R13)
MOVW R2, 12(R13)
MOVW R3, 16(R13)
BL runtime·sighandler(SB)
// restore g
MOVW 20(R13), g
RET
TEXT runtime·rtsigprocmask(SB),NOSPLIT,$0
MOVW 0(FP), R0
MOVW 4(FP), R1
MOVW 8(FP), R2
MOVW 12(FP), R3
MOVW $SYS_rt_sigprocmask, R7
SWI $0
RET
TEXT runtime·rt_sigaction(SB),NOSPLIT,$0
MOVW 0(FP), R0
MOVW 4(FP), R1
MOVW 8(FP), R2
MOVW 12(FP), R3
MOVW $SYS_rt_sigaction, R7
SWI $0
RET
TEXT runtime·sigreturn(SB),NOSPLIT,$0
MOVW $SYS_rt_sigreturn, R7
SWI $0
RET
TEXT runtime·usleep(SB),NOSPLIT,$12
MOVW usec+0(FP), R0
MOVW R0, R1
MOVW $1000000, R2
DIV R2, R0
MOD R2, R1
MOVW R0, 4(SP)
MOVW R1, 8(SP)
MOVW $0, R0
MOVW $0, R1
MOVW $0, R2
MOVW $0, R3
MOVW $4(SP), R4
MOVW $SYS_select, R7
SWI $0
RET
// Use kernel version instead of native armcas in asm_arm.s.
// See ../sync/atomic/asm_linux_arm.s for details.
TEXT cas<>(SB),NOSPLIT,$0
MOVW $0xffff0fc0, PC
TEXT runtime·cas(SB),NOSPLIT,$0
MOVW valptr+0(FP), R2
MOVW old+4(FP), R0
casagain:
MOVW new+8(FP), R1
BL cas<>(SB)
BCC cascheck
MOVW $1, R0
RET
cascheck:
// Kernel lies; double-check.
MOVW valptr+0(FP), R2
MOVW old+4(FP), R0
MOVW 0(R2), R3
CMP R0, R3
BEQ casagain
MOVW $0, R0
RET
TEXT runtime·casp(SB),NOSPLIT,$0
B runtime·cas(SB)
TEXT runtime·osyield(SB),NOSPLIT,$0
MOVW $SYS_sched_yield, R7
SWI $0
RET
TEXT runtime·sched_getaffinity(SB),NOSPLIT,$0
MOVW 0(FP), R0
MOVW 4(FP), R1
MOVW 8(FP), R2
MOVW $SYS_sched_getaffinity, R7
SWI $0
RET
// int32 runtime·epollcreate(int32 size)
TEXT runtime·epollcreate(SB),NOSPLIT,$0
MOVW 0(FP), R0
MOVW $SYS_epoll_create, R7
SWI $0
RET
// int32 runtime·epollcreate1(int32 flags)
TEXT runtime·epollcreate1(SB),NOSPLIT,$0
MOVW 0(FP), R0
MOVW $SYS_epoll_create1, R7
SWI $0
RET
// int32 runtime·epollctl(int32 epfd, int32 op, int32 fd, EpollEvent *ev)
TEXT runtime·epollctl(SB),NOSPLIT,$0
MOVW 0(FP), R0
MOVW 4(FP), R1
MOVW 8(FP), R2
MOVW 12(FP), R3
MOVW $SYS_epoll_ctl, R7
SWI $0
RET
// int32 runtime·epollwait(int32 epfd, EpollEvent *ev, int32 nev, int32 timeout)
TEXT runtime·epollwait(SB),NOSPLIT,$0
MOVW 0(FP), R0
MOVW 4(FP), R1
MOVW 8(FP), R2
MOVW 12(FP), R3
MOVW $SYS_epoll_wait, R7
SWI $0
RET
// void runtime·closeonexec(int32 fd)
TEXT runtime·closeonexec(SB),NOSPLIT,$0
MOVW 0(FP), R0 // fd
MOVW $2, R1 // F_SETFD
MOVW $1, R2 // FD_CLOEXEC
MOVW $SYS_fcntl, R7
SWI $0
RET
// b __kuser_get_tls @ 0xffff0fe0
TEXT runtime·read_tls_fallback(SB),NOSPLIT,$-4
MOVW $0xffff0fe0, R0
B (R0)
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