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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 "386/asm.h"
TEXT runtime·sys_umtx_op(SB),7,$-4
MOVL $454, AX
INT $0x80
RET
TEXT runtime·thr_new(SB),7,$-4
MOVL $455, AX
INT $0x80
RET
TEXT runtime·thr_start(SB),7,$0
MOVL mm+0(FP), AX
MOVL m_g0(AX), BX
LEAL m_tls(AX), BP
MOVL 0(BP), DI
ADDL $7, DI
PUSHAL
PUSHL $32
PUSHL BP
PUSHL DI
CALL runtime·setldt(SB)
POPL AX
POPL AX
POPL AX
POPAL
get_tls(CX)
MOVL BX, g(CX)
MOVL AX, m(CX)
CALL runtime·stackcheck(SB) // smashes AX
CALL runtime·mstart(SB)
MOVL 0, AX // crash (not reached)
// Exit the entire program (like C exit)
TEXT runtime·exit(SB),7,$-4
MOVL $1, AX
INT $0x80
CALL runtime·notok(SB)
RET
TEXT runtime·exit1(SB),7,$-4
MOVL $431, AX
INT $0x80
JAE 2(PC)
CALL runtime·notok(SB)
RET
TEXT runtime·write(SB),7,$-4
MOVL $4, AX
INT $0x80
RET
TEXT runtime·notok(SB),7,$0
MOVL $0xf1, 0xf1
RET
TEXT runtime·mmap(SB),7,$32
LEAL arg0+0(FP), SI
LEAL 4(SP), DI
CLD
MOVSL
MOVSL
MOVSL
MOVSL
MOVSL
MOVSL
MOVL $0, AX // top 64 bits of file offset
STOSL
MOVL $477, AX
INT $0x80
RET
TEXT runtime·munmap(SB),7,$-4
MOVL $73, AX
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 $416, AX
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)
MOVL $417, AX // sigreturn(ucontext)
INT $0x80
CALL runtime·notok(SB)
RET
TEXT runtime·sigaltstack(SB),7,$0
MOVL $53, AX
INT $0x80
JAE 2(PC)
CALL runtime·notok(SB)
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),7,$32
MOVL address+4(FP), BX // aka base
// see comment in linux/386/sys.s; freebsd is similar
ADDL $0x8, 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 runtime·i386_set_ldt(SB)
// compute segment selector - (entry*8+7)
SHLL $3, AX
ADDL $7, AX
MOVW AX, GS
RET
TEXT runtime·i386_set_ldt(SB),7,$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 $165, AX
INT $0x80
CMPL AX, $0xfffff001
JLS 2(PC)
INT $3
RET
GLOBL runtime·tlsoffset(SB),$4
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