libcoro/coro.c

/*
 * Copyright (c) 2001-2008 Marc Alexander Lehmann <schmorp@schmorp.de>
 * 
 * Redistribution and use in source and binary forms, with or without modifica-
 * tion, are permitted provided that the following conditions are met:
 * 
 *   1.  Redistributions of source code must retain the above copyright notice,
 *       this list of conditions and the following disclaimer.
 * 
 *   2.  Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
 * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO
 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
 * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-
 * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * Alternatively, the contents of this file may be used under the terms of
 * the GNU General Public License ("GPL") version 2 or any later version,
 * in which case the provisions of the GPL are applicable instead of
 * the above. If you wish to allow the use of your version of this file
 * only under the terms of the GPL and not to allow others to use your
 * version of this file under the BSD license, indicate your decision
 * by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL. If you do not delete the
 * provisions above, a recipient may use your version of this file under
 * either the BSD or the GPL.
 *
 * This library is modelled strictly after Ralf S. Engelschalls article at
 * http://www.gnu.org/software/pth/rse-pmt.ps. So most of the credit must
 * go to Ralf S. Engelschall <rse@engelschall.com>.
 */

#include "coro.h"

#if !defined(STACK_ADJUST_PTR)
/* IRIX is decidedly NON-unix */
# if __sgi
#  define STACK_ADJUST_PTR(sp,ss) ((char *)(sp) + (ss) - 8)
#  define STACK_ADJUST_SIZE(sp,ss) ((ss) - 8)
# elif __i386__ && CORO_LINUX
#  define STACK_ADJUST_PTR(sp,ss) ((char *)(sp) + (ss))
#  define STACK_ADJUST_SIZE(sp,ss) (ss)
# elif __amd64__ && CORO_LINUX
#  define STACK_ADJUST_PTR(sp,ss) ((char *)(sp) + (ss) - 8)
#  define STACK_ADJUST_SIZE(sp,ss) (ss)
# else
#  define STACK_ADJUST_PTR(sp,ss) (sp)
#  define STACK_ADJUST_SIZE(sp,ss) (ss)
# endif
#endif

#if CORO_UCONTEXT
# include <stddef.h>
#endif

#if CORO_SJLJ || CORO_LOSER || CORO_LINUX || CORO_IRIX || CORO_ASM

#include <stdlib.h>

#if CORO_SJLJ
# include <stdio.h>
# include <signal.h>
# include <unistd.h>
#endif

static volatile coro_func coro_init_func;
static volatile void *coro_init_arg;
static volatile coro_context *new_coro, *create_coro;

/* what we really want to detect here is wether we use a new-enough version of GAS */
/* instead, check for gcc 3, ELF and GNU/Linux and hope for the best */
#if __GNUC__ >= 3 && __ELF__ && __linux__
# define HAVE_CFI 1
#endif

static void
coro_init (void)
{
  volatile coro_func func = coro_init_func;
  volatile void *arg = coro_init_arg;

  coro_transfer ((coro_context *)new_coro, (coro_context *)create_coro);

  func ((void *)arg);

  /* the new coro returned. bad. just abort() for now */
  abort ();
}

# if CORO_SJLJ

static volatile int trampoline_count;

/* trampoline signal handler */
static void
trampoline (int sig)
{
  if (setjmp (((coro_context *)new_coro)->env))
    {
#if HAVE_CFI
      asm (".cfi_startproc");
#endif
      coro_init (); /* start it */
#if HAVE_CFI
      asm (".cfi_endproc");
#endif
    }
  else
    trampoline_count++;
}

# endif

#endif

#if CORO_ASM
void __attribute__((__noinline__, __fastcall__))
coro_transfer (struct coro_context *prev, struct coro_context *next)
{
  asm volatile (
#if __amd64
# define NUM_CLOBBERED 5
     "push %%rbx\n\t"
     "push %%r12\n\t"
     "push %%r13\n\t"
     "push %%r14\n\t"
     "push %%r15\n\t"
     "mov  %%rsp, %0\n\t"
     "mov  %1, %%rsp\n\t"
     "pop  %%r15\n\t"
     "pop  %%r14\n\t"
     "pop  %%r13\n\t"
     "pop  %%r12\n\t"
     "pop  %%rbx\n\t"
#elif __i386
# define NUM_CLOBBERED 4
     "push %%ebx\n\t"
     "push %%esi\n\t"
     "push %%edi\n\t"
     "push %%ebp\n\t"
     "mov  %%esp, %0\n\t"
     "mov  %1, %%esp\n\t"
     "pop  %%ebp\n\t"
     "pop  %%edi\n\t"
     "pop  %%esi\n\t"
     "pop  %%ebx\n\t"
#else
# error unsupported architecture
#endif
     : "=m" (prev->sp)
     : "m" (next->sp)
  );
}
#endif

#if CORO_PTHREAD

struct coro_init_args {
  coro_func func;
  void *arg;
  coro_context *self, *main;
};

pthread_mutex_t coro_mutex = PTHREAD_MUTEX_INITIALIZER;

static void *
trampoline (void *args_)
{
  struct coro_init_args *args = (struct coro_init_args *)args_;
  coro_func func = args->func;
  void *arg = args->arg;

  pthread_mutex_lock (&coro_mutex);
  pthread_cond_destroy (&args->self->c);
  coro_transfer (args->self, args->main);
  func (arg);
  pthread_mutex_unlock (&coro_mutex);

  return 0;
}

void coro_transfer(coro_context *prev, coro_context *next)
{
  pthread_cond_init (&prev->c, 0);
  pthread_cond_signal (&next->c);
  pthread_cond_wait (&prev->c, &coro_mutex);
  pthread_cond_destroy (&prev->c);
}

#endif

/* initialize a machine state */
void coro_create (coro_context *ctx,
                  coro_func coro, void *arg,
                  void *sptr, long ssize)
{
#if CORO_UCONTEXT

  getcontext (&(ctx->uc));

  ctx->uc.uc_link           =  0;
  ctx->uc.uc_stack.ss_sp    = STACK_ADJUST_PTR (sptr,ssize);
  ctx->uc.uc_stack.ss_size  = (size_t) STACK_ADJUST_SIZE (sptr,ssize);
  ctx->uc.uc_stack.ss_flags = 0;

  makecontext (&(ctx->uc), (void (*)()) coro, 1, arg);

#elif CORO_SJLJ || CORO_LOSER || CORO_LINUX || CORO_IRIX || CORO_ASM

# if CORO_SJLJ
  stack_t ostk, nstk;
  struct sigaction osa, nsa;
  sigset_t nsig, osig;
# endif
  coro_context nctx;

  coro_init_func = coro;
  coro_init_arg  = arg;

  new_coro    = ctx;
  create_coro = &nctx;

# if CORO_SJLJ
  /* we use SIGUSR2. first block it, then fiddle with it. */

  sigemptyset (&nsig);
  sigaddset (&nsig, SIGUSR2);
  sigprocmask (SIG_BLOCK, &nsig, &osig);

  nsa.sa_handler = trampoline;
  sigemptyset (&nsa.sa_mask);
  nsa.sa_flags = SA_ONSTACK;

  if (sigaction (SIGUSR2, &nsa, &osa))
    {
      perror ("sigaction");
      abort ();
    }

  /* set the new stack */
  nstk.ss_sp    = STACK_ADJUST_PTR (sptr,ssize); /* yes, some platforms (IRIX) get this wrong. */
  nstk.ss_size  = STACK_ADJUST_SIZE (sptr,ssize);
  nstk.ss_flags = 0;

  if (sigaltstack (&nstk, &ostk) < 0)
    {
      perror ("sigaltstack");
      abort ();
    }

  trampoline_count = 0;
  kill (getpid (), SIGUSR2);
  sigfillset (&nsig); sigdelset (&nsig, SIGUSR2);

  while (!trampoline_count)
    sigsuspend (&nsig);

  sigaltstack (0, &nstk);
  nstk.ss_flags = SS_DISABLE;
  if (sigaltstack (&nstk, 0) < 0)
    perror ("sigaltstack");

  sigaltstack (0, &nstk);
  if (~nstk.ss_flags & SS_DISABLE)
    abort ();

  if (~ostk.ss_flags & SS_DISABLE)
    sigaltstack (&ostk, 0);

  sigaction (SIGUSR2, &osa, 0);

  sigprocmask (SIG_SETMASK, &osig, 0);

# elif CORO_LOSER

  setjmp (ctx->env);
#if __CYGWIN__
  ctx->env[7] = (long)((char *)sptr + ssize);
  ctx->env[8] = (long)coro_init;
#elif defined(_M_IX86)
  ((_JUMP_BUFFER *)&ctx->env)->Eip   = (long)coro_init;
  ((_JUMP_BUFFER *)&ctx->env)->Esp   = (long)STACK_ADJUST_PTR (sptr,ssize);
#elif defined(_M_AMD64)
  ((_JUMP_BUFFER *)&ctx->env)->Rip   = (__int64)coro_init;
  ((_JUMP_BUFFER *)&ctx->env)->Rsp   = (__int64)STACK_ADJUST_PTR (sptr,ssize);
#elif defined(_M_IA64)
  ((_JUMP_BUFFER *)&ctx->env)->StIIP = (__int64)coro_init;
  ((_JUMP_BUFFER *)&ctx->env)->IntSp = (__int64)STACK_ADJUST_PTR (sptr,ssize);
#else
# error "microsoft libc or architecture not supported"
#endif

# elif CORO_LINUX

  _setjmp (ctx->env);
#if __GLIBC__ >= 2 && __GLIBC_MINOR__ >= 0 && defined (JB_PC) && defined (JB_SP)
  ctx->env[0].__jmpbuf[JB_PC] = (long)coro_init;
  ctx->env[0].__jmpbuf[JB_SP] = (long)STACK_ADJUST_PTR (sptr, ssize);
#elif __GLIBC__ >= 2 && __GLIBC_MINOR__ >= 0 && defined (__mc68000__)
  ctx->env[0].__jmpbuf[0].__aregs[0] = (long int)coro_init;
  ctx->env[0].__jmpbuf[0].__sp = (int *)((char *)sptr + ssize);
#elif defined (__GNU_LIBRARY__) && defined (__i386__)
  ctx->env[0].__jmpbuf[0].__pc = (char *)coro_init;
  ctx->env[0].__jmpbuf[0].__sp = (void *)((char *)sptr + ssize);
#elif defined (__GNU_LIBRARY__) && defined (__amd64__)
  ctx->env[0].__jmpbuf[JB_PC]  = (long)coro_init;
  ctx->env[0].__jmpbuf[JB_RSP] = (long)STACK_ADJUST_PTR (sptr, ssize);
#else
# error "linux libc or architecture not supported"
#endif

# elif CORO_IRIX

  setjmp (ctx->env);
  ctx->env[JB_PC] = (__uint64_t)coro_init;
  ctx->env[JB_SP] = (__uint64_t)STACK_ADJUST_PTR (sptr, ssize);

# elif CORO_ASM

  ctx->sp = (volatile void **)(ssize + (char *)sptr);
  *--ctx->sp = (void *)coro_init;
  *--ctx->sp = (void *)coro_init; // this is needed when the prologue saves ebp
  ctx->sp -= NUM_CLOBBERED;

# endif

  coro_transfer ((coro_context *)create_coro, (coro_context *)new_coro);

# elif CORO_PTHREAD

  pthread_t id;
  pthread_attr_t attr;
  coro_context nctx;
  struct coro_init_args args;
  static int once;

  if (!once)
    {
      pthread_mutex_lock (&coro_mutex);
      once = 1;
    }

  args.func = coro;
  args.arg  = arg;
  args.self = ctx;
  args.main = &nctx;

  pthread_attr_init (&attr);
  pthread_attr_setdetachstate (&attr, PTHREAD_CREATE_DETACHED);
  pthread_attr_setstack (&attr, sptr, (size_t)ssize);
  pthread_create (&id, &attr, trampoline, &args);

  pthread_cond_init (&args.self->c, 0);
  coro_transfer (args.main, args.self);

#else
# error unsupported backend
#endif
}

Revision:	1.30
Committed:	Fri Apr 4 20:07:35 2008 UTC (16 years, 1 month ago) by root
Content type:	text/plain
Branch:	MAIN
CVS Tags:	rel-4_50, rel-4_51, rel-4_49, rel-4_48, rel-4_47, rel-4_46
Changes since 1.29:	+65 -2 lines
Log Message:	* empty log message *
#	Content
1	/*
2	* Copyright (c) 2001-2008 Marc Alexander Lehmann <schmorp@schmorp.de>
3	*
4	* Redistribution and use in source and binary forms, with or without modifica-
5	* tion, are permitted provided that the following conditions are met:
6	*
7	* 1. Redistributions of source code must retain the above copyright notice,
8	* this list of conditions and the following disclaimer.
9	*
10	* 2. Redistributions in binary form must reproduce the above copyright
11	* notice, this list of conditions and the following disclaimer in the
12	* documentation and/or other materials provided with the distribution.
13	*
14	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
15	* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
16	* CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
17	* EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
18	* CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19	* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
20	* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
21	* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-
22	* ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
23	* OF THE POSSIBILITY OF SUCH DAMAGE.
24	*
25	* Alternatively, the contents of this file may be used under the terms of
26	* the GNU General Public License ("GPL") version 2 or any later version,
27	* in which case the provisions of the GPL are applicable instead of
28	* the above. If you wish to allow the use of your version of this file
29	* only under the terms of the GPL and not to allow others to use your
30	* version of this file under the BSD license, indicate your decision
31	* by deleting the provisions above and replace them with the notice
32	* and other provisions required by the GPL. If you do not delete the
33	* provisions above, a recipient may use your version of this file under
34	* either the BSD or the GPL.
35	*
36	* This library is modelled strictly after Ralf S. Engelschalls article at
37	* http://www.gnu.org/software/pth/rse-pmt.ps. So most of the credit must
38	* go to Ralf S. Engelschall <rse@engelschall.com>.
39	*/
40
41	#include "coro.h"
42
43	#if !defined(STACK_ADJUST_PTR)
44	/* IRIX is decidedly NON-unix */
45	# if __sgi
46	# define STACK_ADJUST_PTR(sp,ss) ((char *)(sp) + (ss) - 8)
47	# define STACK_ADJUST_SIZE(sp,ss) ((ss) - 8)
48	# elif __i386__ && CORO_LINUX
49	# define STACK_ADJUST_PTR(sp,ss) ((char *)(sp) + (ss))
50	# define STACK_ADJUST_SIZE(sp,ss) (ss)
51	# elif __amd64__ && CORO_LINUX
52	# define STACK_ADJUST_PTR(sp,ss) ((char *)(sp) + (ss) - 8)
53	# define STACK_ADJUST_SIZE(sp,ss) (ss)
54	# else
55	# define STACK_ADJUST_PTR(sp,ss) (sp)
56	# define STACK_ADJUST_SIZE(sp,ss) (ss)
57	# endif
58	#endif
59
60	#if CORO_UCONTEXT
61	# include <stddef.h>
62	#endif
63
64	#if CORO_SJLJ \|\| CORO_LOSER \|\| CORO_LINUX \|\| CORO_IRIX \|\| CORO_ASM
65
66	#include <stdlib.h>
67
68	#if CORO_SJLJ
69	# include <stdio.h>
70	# include <signal.h>
71	# include <unistd.h>
72	#endif
73
74	static volatile coro_func coro_init_func;
75	static volatile void *coro_init_arg;
76	static volatile coro_context new_coro, create_coro;
77
78	/* what we really want to detect here is wether we use a new-enough version of GAS */
79	/* instead, check for gcc 3, ELF and GNU/Linux and hope for the best */
80	#if __GNUC__ >= 3 && __ELF__ && __linux__
81	# define HAVE_CFI 1
82	#endif
83
84	static void
85	coro_init (void)
86	{
87	volatile coro_func func = coro_init_func;
88	volatile void *arg = coro_init_arg;
89
90	coro_transfer ((coro_context )new_coro, (coro_context )create_coro);
91
92	func ((void *)arg);
93
94	/* the new coro returned. bad. just abort() for now */
95	abort ();
96	}
97
98	# if CORO_SJLJ
99
100	static volatile int trampoline_count;
101
102	/* trampoline signal handler */
103	static void
104	trampoline (int sig)
105	{
106	if (setjmp (((coro_context *)new_coro)->env))
107	{
108	#if HAVE_CFI
109	asm (".cfi_startproc");
110	#endif
111	coro_init (); /* start it */
112	#if HAVE_CFI
113	asm (".cfi_endproc");
114	#endif
115	}
116	else
117	trampoline_count++;
118	}
119
120	# endif
121
122	#endif
123
124	#if CORO_ASM
125	void __attribute__((__noinline__, __fastcall__))
126	coro_transfer (struct coro_context prev, struct coro_context next)
127	{
128	asm volatile (
129	#if __amd64
130	# define NUM_CLOBBERED 5
131	"push %%rbx\n\t"
132	"push %%r12\n\t"
133	"push %%r13\n\t"
134	"push %%r14\n\t"
135	"push %%r15\n\t"
136	"mov %%rsp, %0\n\t"
137	"mov %1, %%rsp\n\t"
138	"pop %%r15\n\t"
139	"pop %%r14\n\t"
140	"pop %%r13\n\t"
141	"pop %%r12\n\t"
142	"pop %%rbx\n\t"
143	#elif __i386
144	# define NUM_CLOBBERED 4
145	"push %%ebx\n\t"
146	"push %%esi\n\t"
147	"push %%edi\n\t"
148	"push %%ebp\n\t"
149	"mov %%esp, %0\n\t"
150	"mov %1, %%esp\n\t"
151	"pop %%ebp\n\t"
152	"pop %%edi\n\t"
153	"pop %%esi\n\t"
154	"pop %%ebx\n\t"
155	#else
156	# error unsupported architecture
157	#endif
158	: "=m" (prev->sp)
159	: "m" (next->sp)
160	);
161	}
162	#endif
163
164	#if CORO_PTHREAD
165
166	struct coro_init_args {
167	coro_func func;
168	void *arg;
169	coro_context self, main;
170	};
171
172	pthread_mutex_t coro_mutex = PTHREAD_MUTEX_INITIALIZER;
173
174	static void *
175	trampoline (void *args_)
176	{
177	struct coro_init_args args = (struct coro_init_args )args_;
178	coro_func func = args->func;
179	void *arg = args->arg;
180
181	pthread_mutex_lock (&coro_mutex);
182	pthread_cond_destroy (&args->self->c);
183	coro_transfer (args->self, args->main);
184	func (arg);
185	pthread_mutex_unlock (&coro_mutex);
186
187	return 0;
188	}
189
190	void coro_transfer(coro_context prev, coro_context next)
191	{
192	pthread_cond_init (&prev->c, 0);
193	pthread_cond_signal (&next->c);
194	pthread_cond_wait (&prev->c, &coro_mutex);
195	pthread_cond_destroy (&prev->c);
196	}
197
198	#endif
199
200	/* initialize a machine state */
201	void coro_create (coro_context *ctx,
202	coro_func coro, void *arg,
203	void *sptr, long ssize)
204	{
205	#if CORO_UCONTEXT
206
207	getcontext (&(ctx->uc));
208
209	ctx->uc.uc_link = 0;
210	ctx->uc.uc_stack.ss_sp = STACK_ADJUST_PTR (sptr,ssize);
211	ctx->uc.uc_stack.ss_size = (size_t) STACK_ADJUST_SIZE (sptr,ssize);
212	ctx->uc.uc_stack.ss_flags = 0;
213
214	makecontext (&(ctx->uc), (void (*)()) coro, 1, arg);
215
216	#elif CORO_SJLJ \|\| CORO_LOSER \|\| CORO_LINUX \|\| CORO_IRIX \|\| CORO_ASM
217
218	# if CORO_SJLJ
219	stack_t ostk, nstk;
220	struct sigaction osa, nsa;
221	sigset_t nsig, osig;
222	# endif
223	coro_context nctx;
224
225	coro_init_func = coro;
226	coro_init_arg = arg;
227
228	new_coro = ctx;
229	create_coro = &nctx;
230
231	# if CORO_SJLJ
232	/* we use SIGUSR2. first block it, then fiddle with it. */
233
234	sigemptyset (&nsig);
235	sigaddset (&nsig, SIGUSR2);
236	sigprocmask (SIG_BLOCK, &nsig, &osig);
237
238	nsa.sa_handler = trampoline;
239	sigemptyset (&nsa.sa_mask);
240	nsa.sa_flags = SA_ONSTACK;
241
242	if (sigaction (SIGUSR2, &nsa, &osa))
243	{
244	perror ("sigaction");
245	abort ();
246	}
247
248	/* set the new stack */
249	nstk.ss_sp = STACK_ADJUST_PTR (sptr,ssize); /* yes, some platforms (IRIX) get this wrong. */
250	nstk.ss_size = STACK_ADJUST_SIZE (sptr,ssize);
251	nstk.ss_flags = 0;
252
253	if (sigaltstack (&nstk, &ostk) < 0)
254	{
255	perror ("sigaltstack");
256	abort ();
257	}
258
259	trampoline_count = 0;
260	kill (getpid (), SIGUSR2);
261	sigfillset (&nsig); sigdelset (&nsig, SIGUSR2);
262
263	while (!trampoline_count)
264	sigsuspend (&nsig);
265
266	sigaltstack (0, &nstk);
267	nstk.ss_flags = SS_DISABLE;
268	if (sigaltstack (&nstk, 0) < 0)
269	perror ("sigaltstack");
270
271	sigaltstack (0, &nstk);
272	if (~nstk.ss_flags & SS_DISABLE)
273	abort ();
274
275	if (~ostk.ss_flags & SS_DISABLE)
276	sigaltstack (&ostk, 0);
277
278	sigaction (SIGUSR2, &osa, 0);
279
280	sigprocmask (SIG_SETMASK, &osig, 0);
281
282	# elif CORO_LOSER
283
284	setjmp (ctx->env);
285	#if __CYGWIN__
286	ctx->env[7] = (long)((char *)sptr + ssize);
287	ctx->env[8] = (long)coro_init;
288	#elif defined(_M_IX86)
289	((_JUMP_BUFFER *)&ctx->env)->Eip = (long)coro_init;
290	((_JUMP_BUFFER *)&ctx->env)->Esp = (long)STACK_ADJUST_PTR (sptr,ssize);
291	#elif defined(_M_AMD64)
292	((_JUMP_BUFFER *)&ctx->env)->Rip = (__int64)coro_init;
293	((_JUMP_BUFFER *)&ctx->env)->Rsp = (__int64)STACK_ADJUST_PTR (sptr,ssize);
294	#elif defined(_M_IA64)
295	((_JUMP_BUFFER *)&ctx->env)->StIIP = (__int64)coro_init;
296	((_JUMP_BUFFER *)&ctx->env)->IntSp = (__int64)STACK_ADJUST_PTR (sptr,ssize);
297	#else
298	# error "microsoft libc or architecture not supported"
299	#endif
300
301	# elif CORO_LINUX
302
303	_setjmp (ctx->env);
304	#if __GLIBC__ >= 2 && __GLIBC_MINOR__ >= 0 && defined (JB_PC) && defined (JB_SP)
305	ctx->env[0].__jmpbuf[JB_PC] = (long)coro_init;
306	ctx->env[0].__jmpbuf[JB_SP] = (long)STACK_ADJUST_PTR (sptr, ssize);
307	#elif __GLIBC__ >= 2 && __GLIBC_MINOR__ >= 0 && defined (__mc68000__)
308	ctx->env[0].__jmpbuf[0].__aregs[0] = (long int)coro_init;
309	ctx->env[0].__jmpbuf[0].__sp = (int )((char )sptr + ssize);
310	#elif defined (__GNU_LIBRARY__) && defined (__i386__)
311	ctx->env[0].__jmpbuf[0].__pc = (char *)coro_init;
312	ctx->env[0].__jmpbuf[0].__sp = (void )((char )sptr + ssize);
313	#elif defined (__GNU_LIBRARY__) && defined (__amd64__)
314	ctx->env[0].__jmpbuf[JB_PC] = (long)coro_init;
315	ctx->env[0].__jmpbuf[JB_RSP] = (long)STACK_ADJUST_PTR (sptr, ssize);
316	#else
317	# error "linux libc or architecture not supported"
318	#endif
319
320	# elif CORO_IRIX
321
322	setjmp (ctx->env);
323	ctx->env[JB_PC] = (__uint64_t)coro_init;
324	ctx->env[JB_SP] = (__uint64_t)STACK_ADJUST_PTR (sptr, ssize);
325
326	# elif CORO_ASM
327
328	ctx->sp = (volatile void *)(ssize + (char )sptr);
329	--ctx->sp = (void )coro_init;
330	--ctx->sp = (void )coro_init; // this is needed when the prologue saves ebp
331	ctx->sp -= NUM_CLOBBERED;
332
333	# endif
334
335	coro_transfer ((coro_context )create_coro, (coro_context )new_coro);
336
337	# elif CORO_PTHREAD
338
339	pthread_t id;
340	pthread_attr_t attr;
341	coro_context nctx;
342	struct coro_init_args args;
343	static int once;
344
345	if (!once)
346	{
347	pthread_mutex_lock (&coro_mutex);
348	once = 1;
349	}
350
351	args.func = coro;
352	args.arg = arg;
353	args.self = ctx;
354	args.main = &nctx;
355
356	pthread_attr_init (&attr);
357	pthread_attr_setdetachstate (&attr, PTHREAD_CREATE_DETACHED);
358	pthread_attr_setstack (&attr, sptr, (size_t)ssize);
359	pthread_create (&id, &attr, trampoline, &args);
360
361	pthread_cond_init (&args.self->c, 0);
362	coro_transfer (args.main, args.self);
363
364	#else
365	# error unsupported backend
366	#endif
367	}
368