[gcc.git] / libjava / include / dwarf2-signal.h

// dwarf2-signal.h - Catch runtime signals and turn them into exceptions.

/* Copyright (C) 2000, 2001  Free Software Foundation

   This file is part of libgcj.

   Use this file for a target for which the dwarf2 unwinder in libgcc
   can unwind through signal handlers.

This software is copyrighted work licensed under the terms of the
Libgcj License.  Please consult the file "LIBGCJ_LICENSE" for
details.  */

#ifndef JAVA_SIGNAL_H
#define JAVA_SIGNAL_H 1

#include <signal.h>
#include <sys/syscall.h>

#define HANDLE_SEGV 1
#undef HANDLE_FPE

#define SIGNAL_HANDLER(_name)	\
static void _Jv_##_name (int, siginfo_t *_sip, void *_p)

class java::lang::Throwable;

// Unwind the stack to the point at which the signal was generated and
// then throw an exception.  With the dwarf2 unwinder we don't usually
// need to do anything, with some minor exceptions.

#ifdef __alpha__
#define MAKE_THROW_FRAME(_exception)					\
do									\
{									\
  /* Alpha either leaves PC pointing at a faulting instruction or the	\
   following instruction, depending on the signal.  SEGV always does	\
   the former, so we adjust the saved PC to point to the following	\
   instruction; this is what the handler in libgcc expects.  */		\
  struct sigcontext *_sc = (struct sigcontext *)_p;			\
  _sc->sc_pc += 4;							\
}									\
while (0)

#elif defined(__ia64__)

#define MAKE_THROW_FRAME(_exception)					\
do									\
{									\
  /* IA-64 either leaves PC pointing at a faulting instruction or the	\
   following instruction, depending on the signal.  SEGV always does	\
   the former, so we adjust the saved PC to point to the following	\
   instruction; this is what the handler in libgcc expects.  */		\
  /* Note that we are lying to the unwinder here, which expects the	\
   faulting pc, not pc+1.  But we claim the unwind information can't	\
   be changed by such a ld or st instruction, so it doesn't matter. */	\
  struct sigcontext *_sc = (struct sigcontext *)_p;			\
  _sc->sc_ip++;								\
}									\
while (0)
#elif defined(__sparc__)
/* We could do the unwind of the signal frame quickly by hand here like
   sparc-signal.h does under Solaris, but that makes debugging unwind
   failures almost impossible.  */
#if !defined(__arch64__)
#define MAKE_THROW_FRAME(_exception)					\
do									\
{									\
  /* Sparc-32 leaves PC pointing at a faulting instruction		\
   always.  So we adjust the saved PC to point to the following		\
   instruction; this is what the handler in libgcc expects.  */		\
  /* Note that we are lying to the unwinder here, which expects the	\
   faulting pc, not pc+1.  But we claim the unwind information can't	\
   be changed by such a ld or st instruction, so it doesn't matter. */	\
  struct sig_regs {							\
    unsigned int psr, pc, npc, y, u_regs[16];				\
  } *regp;								\
  unsigned int insn;							\
  __asm__ __volatile__("ld [%%i7 + 8], %0" : "=r" (insn));		\
  /* mov __NR_sigaction, %g1; Old signal stack layout */		\
  if (insn == 0x821020d8)						\
    regp = (struct sig_regs *) _sip;					\
  else									\
    /* mov __NR_rt_sigaction, %g1; New signal stack layout */		\
    regp = (struct sig_regs *) (_sip + 1);				\
  regp->pc = regp->npc;							\
  regp->npc += 4;							\
}									\
while (0)
#else
#define MAKE_THROW_FRAME(_exception)					\
do									\
{									\
  /* Sparc-64 leaves PC pointing at a faulting instruction		\
   always.  So we adjust the saved PC to point to the following		\
   instruction; this is what the handler in libgcc expects.  */		\
  /* Note that we are lying to the unwinder here, which expects the	\
   faulting pc, not pc+1.  But we claim the unwind information can't	\
   be changed by such a ld or st instruction, so it doesn't matter. */	\
  struct pt_regs {							\
    unsigned long u_regs[16];						\
    unsigned long tstate, tpc, tnpc;					\
    unsigned int y, fprs;						\
  } *regp = (struct pt_regs *) (_sip + 1);				\
  regp->tpc = regp->tnpc;						\
  regp->tnpc += 4;							\
}									\
while (0)
#endif
#else
#define MAKE_THROW_FRAME(_exception)		\
do						\
{						\
  (void)_p;					\
}						\
while (0)
#endif

#if !(defined(__ia64__) || defined(__sparc__))
#define INIT_SEGV						\
do								\
  {								\
    nullp = new java::lang::NullPointerException ();    	\
    struct sigaction act;					\
    act.sa_sigaction = _Jv_catch_segv;      			\
    sigemptyset (&act.sa_mask);					\
    act.sa_flags = SA_SIGINFO;	       				\
    syscall (SYS_sigaction, SIGSEGV, &act, NULL);		\
  }								\
while (0)  

#define INIT_FPE						\
do								\
  { 								\
    arithexception = new java::lang::ArithmeticException 	\
      (JvNewStringLatin1 ("/ by zero"));			\
    struct sigaction act;					\
    act.sa_sigaction = _Jv_catch_fpe;				\
    sigemptyset (&act.sa_mask);					\
    act.sa_flags = SA_SIGINFO;		       			\
    syscall (SYS_sigaction, SIGFPE, &act, NULL);		\
  }								\
while (0)  

/* We use syscall(SYS_sigaction) in INIT_SEGV and INIT_FPE instead of
 * sigaction() because on some systems the pthreads wrappers for
 * signal handlers are not compiled with unwind information, so it's
 * not possible to unwind through them.  This is a problem that will
 * go away once all systems have pthreads libraries that are
 * compiled with full unwind info.  */

#else  /* __ia64__ || __sparc__ */

// FIXME: We shouldn't be using libc_sigaction here, since it should
// be glibc private.  But using syscall here would mean translating to
// the kernel's struct sigaction and argument sequence, which we
// shouldn't either.  The right solution is to call sigaction and to
// make sure that we can unwind correctly through the pthread signal
// wrapper.
extern "C" int __libc_sigaction (int __sig, 
		      __const struct sigaction *__restrict __act,
                      struct sigaction *__restrict __oact) throw ();

#define INIT_SEGV						\
do								\
  {								\
    nullp = new java::lang::NullPointerException ();    	\
    struct sigaction act;					\
    act.sa_sigaction = _Jv_catch_segv;      			\
    sigemptyset (&act.sa_mask);					\
    act.sa_flags = SA_SIGINFO;	       				\
    __libc_sigaction (SIGSEGV, &act, NULL);			\
  }								\
while (0)  

#define INIT_FPE						\
do								\
  { 								\
    arithexception = new java::lang::ArithmeticException 	\
      (JvNewStringLatin1 ("/ by zero"));			\
    struct sigaction act;					\
    act.sa_sigaction = _Jv_catch_fpe;				\
    sigemptyset (&act.sa_mask);					\
    act.sa_flags = SA_SIGINFO;		       			\
    __libc_sigaction (SIGFPE, &act, NULL);			\
  }								\
while (0)  
#endif /* __ia64__ || __sparc__ */
#endif /* JAVA_SIGNAL_H */
Commit	Line	Data
01936f3a AH	1	// dwarf2-signal.h - Catch runtime signals and turn them into exceptions.
	2
	3	/* Copyright (C) 2000, 2001 Free Software Foundation
	4
	5	This file is part of libgcj.
	6
c9bffcd5 AH	7	Use this file for a target for which the dwarf2 unwinder in libgcc
c9bffcd5 AH	8	can unwind through signal handlers.
01936f3a AH	9
	10	This software is copyrighted work licensed under the terms of the
	11	Libgcj License. Please consult the file "LIBGCJ_LICENSE" for
	12	details. */
	13
	14	#ifndef JAVA_SIGNAL_H
	15	#define JAVA_SIGNAL_H 1
	16
	17	#include <signal.h>
	18	#include <sys/syscall.h>
	19
	20	#define HANDLE_SEGV 1
	21	#undef HANDLE_FPE
	22
	23	#define SIGNAL_HANDLER(_name) \
714708c8	24	static void _Jv_##_name (int, siginfo_t _sip, void _p)
01936f3a AH	25
	26	class java::lang::Throwable;
	27
	28	// Unwind the stack to the point at which the signal was generated and
c9bffcd5 AH	29	// then throw an exception. With the dwarf2 unwinder we don't usually
	30	// need to do anything, with some minor exceptions.
	31
	32	#ifdef __alpha__
	33	#define MAKE_THROW_FRAME(_exception) \
	34	do \
	35	{ \
	36	/* Alpha either leaves PC pointing at a faulting instruction or the \
	37	following instruction, depending on the signal. SEGV always does \
	38	the former, so we adjust the saved PC to point to the following \
	39	instruction; this is what the handler in libgcc expects. */ \
	40	struct sigcontext _sc = (struct sigcontext )_p; \
	41	_sc->sc_pc += 4; \
	42	} \
	43	while (0)
3cb20545 AH	44
	45	#elif defined(__ia64__)
	46
	47	#define MAKE_THROW_FRAME(_exception) \
	48	do \
	49	{ \
	50	/* IA-64 either leaves PC pointing at a faulting instruction or the \
	51	following instruction, depending on the signal. SEGV always does \
	52	the former, so we adjust the saved PC to point to the following \
	53	instruction; this is what the handler in libgcc expects. */ \
	54	/* Note that we are lying to the unwinder here, which expects the \
	55	faulting pc, not pc+1. But we claim the unwind information can't \
	56	be changed by such a ld or st instruction, so it doesn't matter. */ \
	57	struct sigcontext _sc = (struct sigcontext )_p; \
	58	_sc->sc_ip++; \
	59	} \
	60	while (0)
714708c8 DM	61	#elif defined(__sparc__)
	62	/* We could do the unwind of the signal frame quickly by hand here like
	63	sparc-signal.h does under Solaris, but that makes debugging unwind
	64	failures almost impossible. */
	65	#if !defined(__arch64__)
	66	#define MAKE_THROW_FRAME(_exception) \
	67	do \
	68	{ \
	69	/* Sparc-32 leaves PC pointing at a faulting instruction \
	70	always. So we adjust the saved PC to point to the following \
	71	instruction; this is what the handler in libgcc expects. */ \
	72	/* Note that we are lying to the unwinder here, which expects the \
	73	faulting pc, not pc+1. But we claim the unwind information can't \
	74	be changed by such a ld or st instruction, so it doesn't matter. */ \
	75	struct sig_regs { \
	76	unsigned int psr, pc, npc, y, u_regs[16]; \
	77	} *regp; \
	78	unsigned int insn; \
	79	__asm__ __volatile__("ld [%%i7 + 8], %0" : "=r" (insn)); \
4bf01445	80	/* mov __NR_sigaction, %g1; Old signal stack layout */ \
714708c8 DM	81	if (insn == 0x821020d8) \
	82	regp = (struct sig_regs *) _sip; \
	83	else \
4bf01445	84	/* mov __NR_rt_sigaction, %g1; New signal stack layout */ \
714708c8 DM	85	regp = (struct sig_regs *) (_sip + 1); \
	86	regp->pc = regp->npc; \
	87	regp->npc += 4; \
	88	} \
	89	while (0)
	90	#else
	91	#define MAKE_THROW_FRAME(_exception) \
	92	do \
	93	{ \
	94	/* Sparc-64 leaves PC pointing at a faulting instruction \
	95	always. So we adjust the saved PC to point to the following \
	96	instruction; this is what the handler in libgcc expects. */ \
	97	/* Note that we are lying to the unwinder here, which expects the \
	98	faulting pc, not pc+1. But we claim the unwind information can't \
	99	be changed by such a ld or st instruction, so it doesn't matter. */ \
	100	struct pt_regs { \
	101	unsigned long u_regs[16]; \
	102	unsigned long tstate, tpc, tnpc; \
	103	unsigned int y, fprs; \
	104	} regp = (struct pt_regs ) (_sip + 1); \
	105	regp->tpc = regp->tnpc; \
	106	regp->tnpc += 4; \
	107	} \
	108	while (0)
	109	#endif
c9bffcd5	110	#else
01936f3a AH	111	#define MAKE_THROW_FRAME(_exception) \
	112	do \
	113	{ \
c9bffcd5	114	(void)_p; \
01936f3a AH	115	} \
01936f3a AH	116	while (0)
c9bffcd5	117	#endif
01936f3a	118
714708c8	119	#if !(defined(__ia64__) \|\| defined(__sparc__))
01936f3a AH	120	#define INIT_SEGV \
	121	do \
	122	{ \
	123	nullp = new java::lang::NullPointerException (); \
	124	struct sigaction act; \
c9bffcd5	125	act.sa_sigaction = _Jv_catch_segv; \
01936f3a	126	sigemptyset (&act.sa_mask); \
c9bffcd5	127	act.sa_flags = SA_SIGINFO; \
d6220b3a	128	syscall (SYS_sigaction, SIGSEGV, &act, NULL); \
01936f3a AH	129	} \
	130	while (0)
	131
	132	#define INIT_FPE \
	133	do \
	134	{ \
	135	arithexception = new java::lang::ArithmeticException \
	136	(JvNewStringLatin1 ("/ by zero")); \
	137	struct sigaction act; \
c9bffcd5	138	act.sa_sigaction = _Jv_catch_fpe; \
01936f3a	139	sigemptyset (&act.sa_mask); \
c9bffcd5	140	act.sa_flags = SA_SIGINFO; \
d6220b3a	141	syscall (SYS_sigaction, SIGFPE, &act, NULL); \
01936f3a AH	142	} \
	143	while (0)
	144
	145	/* We use syscall(SYS_sigaction) in INIT_SEGV and INIT_FPE instead of
	146	* sigaction() because on some systems the pthreads wrappers for
	147	* signal handlers are not compiled with unwind information, so it's
	148	* not possible to unwind through them. This is a problem that will
	149	* go away once all systems have pthreads libraries that are
	150	* compiled with full unwind info. */
	151
714708c8	152	#else /* __ia64__ \|\| __sparc__ */
3cb20545 AH	153
	154	// FIXME: We shouldn't be using libc_sigaction here, since it should
	155	// be glibc private. But using syscall here would mean translating to
	156	// the kernel's struct sigaction and argument sequence, which we
	157	// shouldn't either. The right solution is to call sigaction and to
	158	// make sure that we can unwind correctly through the pthread signal
	159	// wrapper.
	160	extern "C" int __libc_sigaction (int __sig,
	161	__const struct sigaction *__restrict __act,
	162	struct sigaction *__restrict __oact) throw ();
	163
	164	#define INIT_SEGV \
	165	do \
	166	{ \
	167	nullp = new java::lang::NullPointerException (); \
	168	struct sigaction act; \
	169	act.sa_sigaction = _Jv_catch_segv; \
	170	sigemptyset (&act.sa_mask); \
	171	act.sa_flags = SA_SIGINFO; \
	172	__libc_sigaction (SIGSEGV, &act, NULL); \
	173	} \
	174	while (0)
	175
	176	#define INIT_FPE \
	177	do \
	178	{ \
	179	arithexception = new java::lang::ArithmeticException \
	180	(JvNewStringLatin1 ("/ by zero")); \
	181	struct sigaction act; \
	182	act.sa_sigaction = _Jv_catch_fpe; \
	183	sigemptyset (&act.sa_mask); \
	184	act.sa_flags = SA_SIGINFO; \
	185	__libc_sigaction (SIGFPE, &act, NULL); \
	186	} \
	187	while (0)
714708c8	188	#endif /* __ia64__ \|\| __sparc__ */
01936f3a	189	#endif /* JAVA_SIGNAL_H */