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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, OpenBSD
// /usr/src/sys/kern/syscalls.master for syscall numbers.
//
#include "386/asm.h"
// Exit the entire program (like C exit)
TEXT runtime·exit(SB),7,$-4
MOVL $1, AX
INT $0x80
CALL runtime·notok(SB)
RET
TEXT runtime·exit1(SB),7,$-4
MOVL $302, AX // sys_threxit
INT $0x80
JAE 2(PC)
CALL runtime·notok(SB)
RET
TEXT runtime·write(SB),7,$-4
MOVL $4, AX // sys_write
INT $0x80
RET
TEXT runtime·raisesigpipe(SB),7,$12
MOVL $299, AX // sys_getthrid
INT $0x80
MOVL $0, 0(SP)
MOVL AX, 4(SP) // arg 1 - pid
MOVL $13, 8(SP) // arg 2 - signum == SIGPIPE
MOVL $37, AX // sys_kill
INT $0x80
RET
TEXT runtime·notok(SB),7,$0
MOVL $0xf1, 0xf1
RET
TEXT runtime·mmap(SB),7,$36
LEAL arg0+0(FP), SI
LEAL 4(SP), DI
CLD
MOVSL // arg 1 - addr
MOVSL // arg 2 - len
MOVSL // arg 3 - prot
MOVSL // arg 4 - flags
MOVSL // arg 5 - fd
MOVL $0, AX
STOSL // arg 6 - pad
MOVSL // arg 7 - offset
MOVL $0, AX // top 64 bits of file offset
STOSL
MOVL $197, AX // sys_mmap
INT $0x80
JCC 2(PC)
NEGL AX
RET
TEXT runtime·munmap(SB),7,$-4
MOVL $73, AX // sys_munmap
INT $0x80
JAE 2(PC)
CALL runtime·notok(SB)
RET
TEXT runtime·setitimer(SB),7,$-4
MOVL $83, AX
INT $0x80
RET
TEXT runtime·gettime(SB),7,$32
MOVL $116, AX
LEAL 12(SP), BX
MOVL BX, 4(SP)
MOVL $0, 8(SP)
INT $0x80
MOVL 12(SP), BX // sec
MOVL sec+0(FP), DI
MOVL BX, (DI)
MOVL $0, 4(DI) // zero extend 32 -> 64 bits
MOVL 16(SP), BX // usec
MOVL usec+4(FP), DI
MOVL BX, (DI)
RET
TEXT runtime·sigaction(SB),7,$-4
MOVL $46, AX // sys_sigaction
INT $0x80
JAE 2(PC)
CALL runtime·notok(SB)
RET
TEXT runtime·sigtramp(SB),7,$44
get_tls(CX)
// save g
MOVL g(CX), DI
MOVL DI, 20(SP)
// g = m->gsignal
MOVL m(CX), BX
MOVL m_gsignal(BX), BX
MOVL BX, g(CX)
// copy arguments for call to sighandler
MOVL signo+0(FP), BX
MOVL BX, 0(SP)
MOVL info+4(FP), BX
MOVL BX, 4(SP)
MOVL context+8(FP), BX
MOVL BX, 8(SP)
MOVL DI, 12(SP)
CALL runtime·sighandler(SB)
// restore g
get_tls(CX)
MOVL 20(SP), BX
MOVL BX, g(CX)
// call sigreturn
MOVL context+8(FP), AX
MOVL $0, 0(SP) // syscall gap
MOVL AX, 4(SP) // arg 1 - sigcontext
MOVL $103, AX // sys_sigreturn
INT $0x80
CALL runtime·notok(SB)
RET
// int32 rfork_thread(int32 flags, void *stack, M *m, G *g, void (*fn)(void));
TEXT runtime·rfork_thread(SB),7,$8
MOVL flags+8(SP), AX
MOVL stack+12(SP), CX
// Copy m, g, fn off parent stack for use by child.
SUBL $16, CX
MOVL mm+16(SP), SI
MOVL SI, 0(CX)
MOVL gg+20(SP), SI
MOVL SI, 4(CX)
MOVL fn+24(SP), SI
MOVL SI, 8(CX)
MOVL $1234, 12(CX)
MOVL CX, SI
MOVL $0, 0(SP) // syscall gap
MOVL AX, 4(SP) // arg 1 - flags
MOVL $251, AX // sys_rfork
INT $0x80
// Return if rfork syscall failed
JCC 4(PC)
NEGL AX
MOVL AX, 48(SP)
RET
// In parent, return.
CMPL AX, $0
JEQ 3(PC)
MOVL AX, 48(SP)
RET
// In child, on new stack.
MOVL SI, SP
// Paranoia: check that SP is as we expect.
MOVL 12(SP), BP
CMPL BP, $1234
JEQ 2(PC)
INT $3
// Reload registers
MOVL 0(SP), BX // m
MOVL 4(SP), DX // g
MOVL 8(SP), SI // fn
// Initialize m->procid to thread ID
MOVL $299, AX // sys_getthrid
INT $0x80
MOVL AX, m_procid(BX)
// Set FS to point at m->tls
LEAL m_tls(BX), BP
PUSHAL // save registers
PUSHL BP
CALL runtime·settls(SB)
POPL AX
POPAL
// Now segment is established. Initialize m, g.
get_tls(AX)
MOVL DX, g(AX)
MOVL BX, m(AX)
CALL runtime·stackcheck(SB) // smashes AX, CX
MOVL 0(DX), DX // paranoia; check they are not nil
MOVL 0(BX), BX
// more paranoia; check that stack splitting code works
PUSHAL
CALL runtime·emptyfunc(SB)
POPAL
// Call fn
CALL SI
CALL runtime·exit1(SB)
MOVL $0x1234, 0x1005
RET
TEXT runtime·sigaltstack(SB),7,$-8
MOVL $288, AX // sys_sigaltstack
MOVL new+4(SP), BX
MOVL old+8(SP), CX
INT $0x80
CMPL AX, $0xfffff001
JLS 2(PC)
INT $3
RET
TEXT runtime·setldt(SB),7,$8
// Under OpenBSD we set the GS base instead of messing with the LDT.
MOVL 16(SP), AX // tls0
MOVL AX, 0(SP)
CALL runtime·settls(SB)
RET
TEXT runtime·settls(SB),7,$16
// adjust for ELF: wants to use -8(GS) and -4(GS) for g and m
MOVL 20(SP), CX
ADDL $8, CX
MOVL CX, 0(CX)
MOVL $0, 0(SP) // syscall gap
MOVL $9, 4(SP) // I386_SET_GSBASE (machine/sysarch.h)
MOVL CX, 8(SP) // pointer to base
MOVL $165, AX // sys_sysarch
INT $0x80
JCC 2(PC)
CALL runtime·notok(SB)
RET
TEXT runtime·osyield(SB),7,$-4
MOVL $298, AX // sys_sched_yield
INT $0x80
RET
GLOBL runtime·tlsoffset(SB),$4
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