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Diffstat (limited to 'libthreads/i386/csw.S')
| -rw-r--r-- | libthreads/i386/csw.S | 185 |
1 files changed, 185 insertions, 0 deletions
diff --git a/libthreads/i386/csw.S b/libthreads/i386/csw.S new file mode 100644 index 00000000..5579db5c --- /dev/null +++ b/libthreads/i386/csw.S @@ -0,0 +1,185 @@ +/* + * Mach Operating System + * Copyright (c) 1991,1990,1989 Carnegie Mellon University + * All Rights Reserved. + * + * Permission to use, copy, modify and distribute this software and its + * documentation is hereby granted, provided that both the copyright + * notice and this permission notice appear in all copies of the + * software, derivative works or modified versions, and any portions + * thereof, and that both notices appear in supporting documentation. + * + * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" + * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR + * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. + * + * Carnegie Mellon requests users of this software to return to + * + * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU + * School of Computer Science + * Carnegie Mellon University + * Pittsburgh PA 15213-3890 + * + * any improvements or extensions that they make and grant Carnegie Mellon + * the rights to redistribute these changes. + */ +/* + * HISTORY + * $Log: csw.S,v $ + * Revision 1.8 1997/04/04 01:31:16 thomas + * Thu Apr 3 20:29:27 1997 Thomas Bushnell, n/BSG <thomas@gnu.ai.mit.edu> + * + * * i386/csw.S: Define __ELF__ too. + * + * Revision 1.7 1996/10/24 19:30:10 thomas + * Mon Oct 21 22:05:48 1996 Thomas Bushnell, n/BSG <thomas@gnu.ai.mit.edu> + * + * * i386/csw.S (CALL_MCOUNT): New macro. + * (cproc_swtich, cproc_start_wait, cproc_prepare): Use CALL_MCOUNT. + * + * Revision 1.6 1996/08/29 17:44:42 thomas + * *** empty log message *** + * + * Revision 1.5 1995/10/04 20:55:28 roland + * (JUMPTARGET): New macro, versions for [PIC] and not. + * Use it in place of EXT. + * + * Revision 1.4 1995/10/04 20:22:17 roland + * [PIC] (EXT): Redefine to use PLT. + * + * Revision 1.3 1995/05/12 18:35:55 roland + * Use EXT macro instead of explicit underscores. + * +# Revision 1.2 1994/05/04 19:01:50 mib +# entered into RCS +# + * Revision 2.7 91/07/31 18:36:32 dbg + * Fix for ANSI C preprocessor. + * [91/07/30 17:35:16 dbg] + * + * Revision 2.6 91/05/14 17:56:56 mrt + * Correcting copyright + * + * Revision 2.5 91/05/08 13:35:49 dbg + * Unlock lock with a locked instruction (xchg). + * [91/03/20 dbg] + * + * Revision 2.4 91/02/14 14:20:02 mrt + * Changed to new Mach copyright + * [91/02/13 12:15:27 mrt] + * + * Revision 2.3 91/01/08 16:46:20 rpd + * Don't use Times - horta doesn't like it for some reason. + * [91/01/06 rpd] + * + * Revision 2.2 90/05/03 15:54:37 dbg + * Created. + * [90/02/05 dbg] + * + */ +#define ELF +#define __ELF__ +#include <mach/i386/asm.h> + +#ifdef PIC +#define JUMPTARGET(name) EXT(name##@PLT) +#else +#define JUMPTARGET(name) EXT(name) +#endif + +#ifdef PROF +#define CALL_MCOUNT \ + pushl %ebp; movl %esp, %ebp; call JUMPTARGET(mcount); popl %ebp; +#else +#define CALL_MCOUNT +#endif + + +/* + * Suspend the current thread and resume the next one. + * + * void cproc_switch(int *cur, int *next, int *lock) + */ +ENTRY(cproc_switch) + CALL_MCOUNT + pushl %ebp /* save ebp */ + movl %esp,%ebp /* set frame pointer to get arguments */ + pushl %ebx /* save ebx */ + pushl %esi /* esi */ + pushl %edi /* edi */ + movl B_ARG0,%eax /* get cur */ + movl %esp,(%eax) /* save current esp */ + movl B_ARG2,%edx /* get address of lock before switching */ + /* stacks */ + movl B_ARG1,%eax /* get next */ + movl (%eax),%esp /* get new stack pointer */ + xorl %eax,%eax /* unlock */ + xchgl %eax,(%edx) /* the lock - now old thread can run */ + + popl %edi /* restore di */ + popl %esi /* si */ + popl %ebx /* bx */ + popl %ebp /* and bp (don`t use "leave" - bp */ + /* still points to old stack) */ + ret + +/* + * Create a new stack frame for a 'waiting' thread, + * save current thread's frame, and switch to waiting thread. + * + * void cproc_start_wait(int *cur, + * cproc_t child, + * int stackp, + * int *lock) + */ +ENTRY(cproc_start_wait) + CALL_MCOUNT + pushl %ebp /* save ebp */ + movl %esp,%ebp /* set frame pointer */ + pushl %ebx /* save ebx */ + pushl %esi /* esi */ + pushl %edi /* edi */ + movl B_ARG0,%eax /* get cur */ + movl %esp,(%eax) /* save current esp */ + movl B_ARG1,%eax /* get child thread */ + movl B_ARG3,%edx /* point to lock before switching stack */ + movl B_ARG2,%esp /* get new stack */ + pushl %eax /* push child thread as argument */ + movl $0,%ebp /* (clear frame pointer) */ + xorl %eax,%eax /* unlock */ + xchgl %eax,(%edx) /* the lock - now old thread can run */ + call JUMPTARGET(cproc_waiting)/* call cproc_waiting */ + /*NOTREACHED*/ + +/* + * Set up a thread's stack so that when cproc_switch switches to + * it, it will start up as if it called + * cproc_body(child) + * + * void cproc_prepare(cproc_t child, int *context, int stack, + * void (*cthread_body)(cproc_t)); + */ +ENTRY(cproc_prepare) + CALL_MCOUNT + pushl %ebp /* save ebp */ + movl %esp,%ebp /* set frame pointer */ + movl B_ARG2,%edx /* get child`s stack */ + subl $28,%edx + /* make room for context: */ + /* 0 saved edi () */ + /* 4 saved esi () */ + /* 8 saved ebx () */ + /* 12 saved ebp () */ + /* 16 return PC from cproc_switch */ + /* 20 return PC from cthread_body */ + /* 24 argument to cthread_body */ + movl $0,12(%edx) /* clear frame pointer */ + movl B_ARG3,%ecx /* get address of cthread_body passed in */ + movl %ecx,16(%edx) /* set child to resume at cthread_body */ + movl $0,20(%edx) /* fake return address from cthread_body */ + movl B_ARG0,%ecx /* get child thread pointer */ + movl %ecx,24(%edx) /* set as argument to cthread_body */ + movl B_ARG1,%ecx /* get pointer to context */ + movl %edx,(%ecx) /* save context */ + leave + ret |