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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 386, FreeBSD
// /usr/src/sys/kern/syscalls.master for syscall numbers.
//
#include "go_asm.h"
#include "go_tls.h"
#include "textflag.h"
#define CLOCK_REALTIME 0
#define CLOCK_MONOTONIC 4
#define SYS_exit 1
#define SYS_read 3
#define SYS_write 4
#define SYS_open 5
#define SYS_close 6
#define SYS_getpid 20
#define SYS_kill 37
#define SYS_sigaltstack 53
#define SYS_munmap 73
#define SYS_madvise 75
#define SYS_setitimer 83
#define SYS_fcntl 92
#define SYS_sysarch 165
#define SYS___sysctl 202
#define SYS_clock_gettime 232
#define SYS_nanosleep 240
#define SYS_issetugid 253
#define SYS_sched_yield 331
#define SYS_sigprocmask 340
#define SYS_kqueue 362
#define SYS_sigaction 416
#define SYS_sigreturn 417
#define SYS_thr_exit 431
#define SYS_thr_self 432
#define SYS_thr_kill 433
#define SYS__umtx_op 454
#define SYS_thr_new 455
#define SYS_mmap 477
#define SYS_cpuset_getaffinity 487
#define SYS_pipe2 542
#define SYS_kevent 560
TEXT runtime·sys_umtx_op(SB),NOSPLIT,$-4
MOVL $SYS__umtx_op, AX
INT $0x80
JAE 2(PC)
NEGL AX
MOVL AX, ret+20(FP)
RET
TEXT runtime·thr_new(SB),NOSPLIT,$-4
MOVL $SYS_thr_new, AX
INT $0x80
JAE 2(PC)
NEGL AX
MOVL AX, ret+8(FP)
RET
// Called by OS using C ABI.
TEXT runtime·thr_start(SB),NOSPLIT,$0
NOP SP // tell vet SP changed - stop checking offsets
MOVL 4(SP), AX // m
MOVL m_g0(AX), BX
LEAL m_tls(AX), BP
MOVL m_id(AX), DI
ADDL $7, DI
PUSHAL
PUSHL $32
PUSHL BP
PUSHL DI
CALL runtime·setldt(SB)
POPL AX
POPL AX
POPL AX
POPAL
get_tls(CX)
MOVL BX, g(CX)
MOVL AX, g_m(BX)
CALL runtime·stackcheck(SB) // smashes AX
CALL runtime·mstart(SB)
MOVL 0, AX // crash (not reached)
// Exit the entire program (like C exit)
TEXT runtime·exit(SB),NOSPLIT,$-4
MOVL $SYS_exit, AX
INT $0x80
MOVL $0xf1, 0xf1 // crash
RET
GLOBL exitStack<>(SB),RODATA,$8
DATA exitStack<>+0x00(SB)/4, $0
DATA exitStack<>+0x04(SB)/4, $0
// func exitThread(wait *atomic.Uint32)
TEXT runtime·exitThread(SB),NOSPLIT,$0-4
MOVL wait+0(FP), AX
// We're done using the stack.
MOVL $0, (AX)
// thr_exit takes a single pointer argument, which it expects
// on the stack. We want to pass 0, so switch over to a fake
// stack of 0s. It won't write to the stack.
MOVL $exitStack<>(SB), SP
MOVL $SYS_thr_exit, AX
INT $0x80
MOVL $0xf1, 0xf1 // crash
JMP 0(PC)
TEXT runtime·open(SB),NOSPLIT,$-4
MOVL $SYS_open, AX
INT $0x80
JAE 2(PC)
MOVL $-1, AX
MOVL AX, ret+12(FP)
RET
TEXT runtime·closefd(SB),NOSPLIT,$-4
MOVL $SYS_close, AX
INT $0x80
JAE 2(PC)
MOVL $-1, AX
MOVL AX, ret+4(FP)
RET
TEXT runtime·read(SB),NOSPLIT,$-4
MOVL $SYS_read, AX
INT $0x80
JAE 2(PC)
NEGL AX // caller expects negative errno
MOVL AX, ret+12(FP)
RET
// func pipe2(flags int32) (r, w int32, errno int32)
TEXT runtime·pipe2(SB),NOSPLIT,$12-16
MOVL $SYS_pipe2, AX
LEAL r+4(FP), BX
MOVL BX, 4(SP)
MOVL flags+0(FP), BX
MOVL BX, 8(SP)
INT $0x80
JAE 2(PC)
NEGL AX
MOVL AX, errno+12(FP)
RET
TEXT runtime·write1(SB),NOSPLIT,$-4
MOVL $SYS_write, AX
INT $0x80
JAE 2(PC)
NEGL AX // caller expects negative errno
MOVL AX, ret+12(FP)
RET
TEXT runtime·thr_self(SB),NOSPLIT,$8-4
// thr_self(&0(FP))
LEAL ret+0(FP), AX
MOVL AX, 4(SP)
MOVL $SYS_thr_self, AX
INT $0x80
RET
TEXT runtime·thr_kill(SB),NOSPLIT,$-4
// thr_kill(tid, sig)
MOVL $SYS_thr_kill, AX
INT $0x80
RET
TEXT runtime·raiseproc(SB),NOSPLIT,$16
// getpid
MOVL $SYS_getpid, AX
INT $0x80
// kill(self, sig)
MOVL AX, 4(SP)
MOVL sig+0(FP), AX
MOVL AX, 8(SP)
MOVL $SYS_kill, AX
INT $0x80
RET
TEXT runtime·mmap(SB),NOSPLIT,$32
LEAL addr+0(FP), SI
LEAL 4(SP), DI
CLD
MOVSL
MOVSL
MOVSL
MOVSL
MOVSL
MOVSL
MOVL $0, AX // top 32 bits of file offset
STOSL
MOVL $SYS_mmap, AX
INT $0x80
JAE ok
MOVL $0, p+24(FP)
MOVL AX, err+28(FP)
RET
ok:
MOVL AX, p+24(FP)
MOVL $0, err+28(FP)
RET
TEXT runtime·munmap(SB),NOSPLIT,$-4
MOVL $SYS_munmap, AX
INT $0x80
JAE 2(PC)
MOVL $0xf1, 0xf1 // crash
RET
TEXT runtime·madvise(SB),NOSPLIT,$-4
MOVL $SYS_madvise, AX
INT $0x80
JAE 2(PC)
MOVL $-1, AX
MOVL AX, ret+12(FP)
RET
TEXT runtime·setitimer(SB), NOSPLIT, $-4
MOVL $SYS_setitimer, AX
INT $0x80
RET
// func fallback_walltime() (sec int64, nsec int32)
TEXT runtime·fallback_walltime(SB), NOSPLIT, $32-12
MOVL $SYS_clock_gettime, AX
LEAL 12(SP), BX
MOVL $CLOCK_REALTIME, 4(SP)
MOVL BX, 8(SP)
INT $0x80
MOVL 12(SP), AX // sec
MOVL 16(SP), BX // nsec
// sec is in AX, nsec in BX
MOVL AX, sec_lo+0(FP)
MOVL $0, sec_hi+4(FP)
MOVL BX, nsec+8(FP)
RET
// func fallback_nanotime() int64
TEXT runtime·fallback_nanotime(SB), NOSPLIT, $32-8
MOVL $SYS_clock_gettime, AX
LEAL 12(SP), BX
MOVL $CLOCK_MONOTONIC, 4(SP)
MOVL BX, 8(SP)
INT $0x80
MOVL 12(SP), AX // sec
MOVL 16(SP), BX // nsec
// sec is in AX, nsec in BX
// convert to DX:AX nsec
MOVL $1000000000, CX
MULL CX
ADDL BX, AX
ADCL $0, DX
MOVL AX, ret_lo+0(FP)
MOVL DX, ret_hi+4(FP)
RET
TEXT runtime·asmSigaction(SB),NOSPLIT,$-4
MOVL $SYS_sigaction, AX
INT $0x80
MOVL AX, ret+12(FP)
RET
TEXT runtime·sigfwd(SB),NOSPLIT,$12-16
MOVL fn+0(FP), AX
MOVL sig+4(FP), BX
MOVL info+8(FP), CX
MOVL ctx+12(FP), DX
MOVL SP, SI
SUBL $32, SP
ANDL $~15, SP // align stack: handler might be a C function
MOVL BX, 0(SP)
MOVL CX, 4(SP)
MOVL DX, 8(SP)
MOVL SI, 12(SP) // save SI: handler might be a Go function
CALL AX
MOVL 12(SP), AX
MOVL AX, SP
RET
// Called by OS using C ABI.
TEXT runtime·sigtramp(SB),NOSPLIT|TOPFRAME,$12
NOP SP // tell vet SP changed - stop checking offsets
MOVL 16(SP), BX // signo
MOVL BX, 0(SP)
MOVL 20(SP), BX // info
MOVL BX, 4(SP)
MOVL 24(SP), BX // context
MOVL BX, 8(SP)
CALL runtime·sigtrampgo(SB)
// call sigreturn
MOVL 24(SP), AX // context
MOVL $0, 0(SP) // syscall gap
MOVL AX, 4(SP)
MOVL $SYS_sigreturn, AX
INT $0x80
MOVL $0xf1, 0xf1 // crash
RET
TEXT runtime·sigaltstack(SB),NOSPLIT,$0
MOVL $SYS_sigaltstack, AX
INT $0x80
JAE 2(PC)
MOVL $0xf1, 0xf1 // crash
RET
TEXT runtime·usleep(SB),NOSPLIT,$20
MOVL $0, DX
MOVL usec+0(FP), AX
MOVL $1000000, CX
DIVL CX
MOVL AX, 12(SP) // tv_sec
MOVL $1000, AX
MULL DX
MOVL AX, 16(SP) // tv_nsec
MOVL $0, 0(SP)
LEAL 12(SP), AX
MOVL AX, 4(SP) // arg 1 - rqtp
MOVL $0, 8(SP) // arg 2 - rmtp
MOVL $SYS_nanosleep, AX
INT $0x80
RET
/*
descriptor entry format for system call
is the native machine format, ugly as it is:
2-byte limit
3-byte base
1-byte: 0x80=present, 0x60=dpl<<5, 0x1F=type
1-byte: 0x80=limit is *4k, 0x40=32-bit operand size,
0x0F=4 more bits of limit
1 byte: 8 more bits of base
int i386_get_ldt(int, union ldt_entry *, int);
int i386_set_ldt(int, const union ldt_entry *, int);
*/
// setldt(int entry, int address, int limit)
TEXT runtime·setldt(SB),NOSPLIT,$32
MOVL base+4(FP), BX
// see comment in sys_linux_386.s; freebsd is similar
ADDL $0x4, BX
// set up data_desc
LEAL 16(SP), AX // struct data_desc
MOVL $0, 0(AX)
MOVL $0, 4(AX)
MOVW BX, 2(AX)
SHRL $16, BX
MOVB BX, 4(AX)
SHRL $8, BX
MOVB BX, 7(AX)
MOVW $0xffff, 0(AX)
MOVB $0xCF, 6(AX) // 32-bit operand, 4k limit unit, 4 more bits of limit
MOVB $0xF2, 5(AX) // r/w data descriptor, dpl=3, present
// call i386_set_ldt(entry, desc, 1)
MOVL $0xffffffff, 0(SP) // auto-allocate entry and return in AX
MOVL AX, 4(SP)
MOVL $1, 8(SP)
CALL i386_set_ldt<>(SB)
// compute segment selector - (entry*8+7)
SHLL $3, AX
ADDL $7, AX
MOVW AX, GS
RET
TEXT i386_set_ldt<>(SB),NOSPLIT,$16
LEAL args+0(FP), AX // 0(FP) == 4(SP) before SP got moved
MOVL $0, 0(SP) // syscall gap
MOVL $1, 4(SP)
MOVL AX, 8(SP)
MOVL $SYS_sysarch, AX
INT $0x80
JAE 2(PC)
INT $3
RET
TEXT runtime·sysctl(SB),NOSPLIT,$28
LEAL mib+0(FP), SI
LEAL 4(SP), DI
CLD
MOVSL // arg 1 - name
MOVSL // arg 2 - namelen
MOVSL // arg 3 - oldp
MOVSL // arg 4 - oldlenp
MOVSL // arg 5 - newp
MOVSL // arg 6 - newlen
MOVL $SYS___sysctl, AX
INT $0x80
JAE 4(PC)
NEGL AX
MOVL AX, ret+24(FP)
RET
MOVL $0, AX
MOVL AX, ret+24(FP)
RET
TEXT runtime·osyield(SB),NOSPLIT,$-4
MOVL $SYS_sched_yield, AX
INT $0x80
RET
TEXT runtime·sigprocmask(SB),NOSPLIT,$16
MOVL $0, 0(SP) // syscall gap
MOVL how+0(FP), AX // arg 1 - how
MOVL AX, 4(SP)
MOVL new+4(FP), AX
MOVL AX, 8(SP) // arg 2 - set
MOVL old+8(FP), AX
MOVL AX, 12(SP) // arg 3 - oset
MOVL $SYS_sigprocmask, AX
INT $0x80
JAE 2(PC)
MOVL $0xf1, 0xf1 // crash
RET
// int32 runtime·kqueue(void);
TEXT runtime·kqueue(SB),NOSPLIT,$0
MOVL $SYS_kqueue, AX
INT $0x80
JAE 2(PC)
NEGL AX
MOVL AX, ret+0(FP)
RET
// int32 runtime·kevent(int kq, Kevent *changelist, int nchanges, Kevent *eventlist, int nevents, Timespec *timeout);
TEXT runtime·kevent(SB),NOSPLIT,$0
MOVL $SYS_kevent, AX
INT $0x80
JAE 2(PC)
NEGL AX
MOVL AX, ret+24(FP)
RET
// func fcntl(fd, cmd, arg int32) (int32, int32)
TEXT runtime·fcntl(SB),NOSPLIT,$-4
MOVL $SYS_fcntl, AX
INT $0x80
JAE noerr
MOVL $-1, ret+12(FP)
MOVL AX, errno+16(FP)
RET
noerr:
MOVL AX, ret+12(FP)
MOVL $0, errno+16(FP)
RET
// func cpuset_getaffinity(level int, which int, id int64, size int, mask *byte) int32
TEXT runtime·cpuset_getaffinity(SB), NOSPLIT, $0-28
MOVL $SYS_cpuset_getaffinity, AX
INT $0x80
JAE 2(PC)
NEGL AX
MOVL AX, ret+24(FP)
RET
GLOBL runtime·tlsoffset(SB),NOPTR,$4
// func issetugid() int32
TEXT runtime·issetugid(SB),NOSPLIT,$0
MOVL $SYS_issetugid, AX
INT $0x80
MOVL AX, ret+0(FP)
RET