281 lines
6.4 KiB
C
281 lines
6.4 KiB
C
/* DWARF2 exception handling and frame unwind runtime interface routines.
|
||
Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002
|
||
Free Software Foundation, Inc.
|
||
|
||
This file is part of GCC.
|
||
|
||
GCC is free software; you can redistribute it and/or modify it
|
||
under the terms of the GNU General Public License as published by
|
||
the Free Software Foundation; either version 2, or (at your option)
|
||
any later version.
|
||
|
||
GCC is distributed in the hope that it will be useful, but WITHOUT
|
||
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
|
||
or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
|
||
License for more details.
|
||
|
||
You should have received a copy of the GNU General Public License
|
||
along with GCC; see the file COPYING. If not, write to the Free
|
||
Software Foundation, 59 Temple Place - Suite 330, Boston, MA
|
||
02111-1307, USA. */
|
||
|
||
#include "tconfig.h"
|
||
#include "tsystem.h"
|
||
#include "unwind.h"
|
||
#include "gthr.h"
|
||
|
||
#ifdef __USING_SJLJ_EXCEPTIONS__
|
||
|
||
#ifdef DONT_USE_BUILTIN_SETJMP
|
||
#ifndef inhibit_libc
|
||
#include <setjmp.h>
|
||
#else
|
||
typedef void *jmp_buf[JMP_BUF_SIZE];
|
||
extern void longjmp(jmp_buf, int) __attribute__((noreturn));
|
||
#endif
|
||
#else
|
||
#define setjmp __builtin_setjmp
|
||
#define longjmp __builtin_longjmp
|
||
#endif
|
||
|
||
/* This structure is allocated on the stack of the target function.
|
||
This must match the definition created in except.c:init_eh. */
|
||
struct SjLj_Function_Context
|
||
{
|
||
/* This is the chain through all registered contexts. It is
|
||
filled in by _Unwind_SjLj_Register. */
|
||
struct SjLj_Function_Context *prev;
|
||
|
||
/* This is assigned in by the target function before every call
|
||
to the index of the call site in the lsda. It is assigned by
|
||
the personality routine to the landing pad index. */
|
||
int call_site;
|
||
|
||
/* This is how data is returned from the personality routine to
|
||
the target function's handler. */
|
||
_Unwind_Word data[4];
|
||
|
||
/* These are filled in once by the target function before any
|
||
exceptions are expected to be handled. */
|
||
_Unwind_Personality_Fn personality;
|
||
void *lsda;
|
||
|
||
#ifdef DONT_USE_BUILTIN_SETJMP
|
||
/* We don't know what sort of alignment requirements the system
|
||
jmp_buf has. We over estimated in except.c, and now we have
|
||
to match that here just in case the system *didn't* have more
|
||
restrictive requirements. */
|
||
jmp_buf jbuf __attribute__((aligned));
|
||
#else
|
||
void *jbuf[];
|
||
#endif
|
||
};
|
||
|
||
struct _Unwind_Context
|
||
{
|
||
struct SjLj_Function_Context *fc;
|
||
};
|
||
|
||
typedef struct
|
||
{
|
||
_Unwind_Personality_Fn personality;
|
||
} _Unwind_FrameState;
|
||
|
||
|
||
/* Manage the chain of registered function contexts. */
|
||
|
||
/* Single threaded fallback chain. */
|
||
static struct SjLj_Function_Context *fc_static;
|
||
|
||
#if __GTHREADS
|
||
static __gthread_key_t fc_key;
|
||
static int use_fc_key = -1;
|
||
|
||
static void
|
||
fc_key_dtor (void *ptr)
|
||
{
|
||
__gthread_key_dtor (fc_key, ptr);
|
||
}
|
||
|
||
static void
|
||
fc_key_init (void)
|
||
{
|
||
use_fc_key = __gthread_key_create (&fc_key, fc_key_dtor) == 0;
|
||
}
|
||
|
||
static void
|
||
fc_key_init_once (void)
|
||
{
|
||
static __gthread_once_t once = __GTHREAD_ONCE_INIT;
|
||
if (__gthread_once (&once, fc_key_init) != 0 || use_fc_key < 0)
|
||
use_fc_key = 0;
|
||
}
|
||
#endif
|
||
|
||
void
|
||
_Unwind_SjLj_Register (struct SjLj_Function_Context *fc)
|
||
{
|
||
#if __GTHREADS
|
||
if (use_fc_key < 0)
|
||
fc_key_init_once ();
|
||
|
||
if (use_fc_key)
|
||
{
|
||
fc->prev = __gthread_getspecific (fc_key);
|
||
__gthread_setspecific (fc_key, fc);
|
||
}
|
||
else
|
||
#endif
|
||
{
|
||
fc->prev = fc_static;
|
||
fc_static = fc;
|
||
}
|
||
}
|
||
|
||
static inline struct SjLj_Function_Context *
|
||
_Unwind_SjLj_GetContext (void)
|
||
{
|
||
#if __GTHREADS
|
||
if (use_fc_key < 0)
|
||
fc_key_init_once ();
|
||
|
||
if (use_fc_key)
|
||
return __gthread_getspecific (fc_key);
|
||
#endif
|
||
return fc_static;
|
||
}
|
||
|
||
static inline void
|
||
_Unwind_SjLj_SetContext (struct SjLj_Function_Context *fc)
|
||
{
|
||
#if __GTHREADS
|
||
if (use_fc_key < 0)
|
||
fc_key_init_once ();
|
||
|
||
if (use_fc_key)
|
||
__gthread_setspecific (fc_key, fc);
|
||
else
|
||
#endif
|
||
fc_static = fc;
|
||
}
|
||
|
||
void
|
||
_Unwind_SjLj_Unregister (struct SjLj_Function_Context *fc)
|
||
{
|
||
_Unwind_SjLj_SetContext (fc->prev);
|
||
}
|
||
|
||
|
||
/* Get/set the return data value at INDEX in CONTEXT. */
|
||
|
||
_Unwind_Word
|
||
_Unwind_GetGR (struct _Unwind_Context *context, int index)
|
||
{
|
||
return context->fc->data[index];
|
||
}
|
||
|
||
void
|
||
_Unwind_SetGR (struct _Unwind_Context *context, int index, _Unwind_Word val)
|
||
{
|
||
context->fc->data[index] = val;
|
||
}
|
||
|
||
/* Get the call-site index as saved in CONTEXT. */
|
||
|
||
_Unwind_Ptr
|
||
_Unwind_GetIP (struct _Unwind_Context *context)
|
||
{
|
||
return context->fc->call_site + 1;
|
||
}
|
||
|
||
/* Set the return landing pad index in CONTEXT. */
|
||
|
||
void
|
||
_Unwind_SetIP (struct _Unwind_Context *context, _Unwind_Ptr val)
|
||
{
|
||
context->fc->call_site = val - 1;
|
||
}
|
||
|
||
void *
|
||
_Unwind_GetLanguageSpecificData (struct _Unwind_Context *context)
|
||
{
|
||
return context->fc->lsda;
|
||
}
|
||
|
||
_Unwind_Ptr
|
||
_Unwind_GetRegionStart (struct _Unwind_Context *context __attribute__((unused)) )
|
||
{
|
||
return 0;
|
||
}
|
||
|
||
#ifndef __ia64__
|
||
_Unwind_Ptr
|
||
_Unwind_GetDataRelBase (struct _Unwind_Context *context __attribute__((unused)) )
|
||
{
|
||
return 0;
|
||
}
|
||
|
||
_Unwind_Ptr
|
||
_Unwind_GetTextRelBase (struct _Unwind_Context *context __attribute__((unused)) )
|
||
{
|
||
return 0;
|
||
}
|
||
#endif
|
||
|
||
static inline _Unwind_Reason_Code
|
||
uw_frame_state_for (struct _Unwind_Context *context, _Unwind_FrameState *fs)
|
||
{
|
||
if (context->fc == NULL)
|
||
{
|
||
fs->personality = NULL;
|
||
return _URC_END_OF_STACK;
|
||
}
|
||
else
|
||
{
|
||
fs->personality = context->fc->personality;
|
||
return _URC_NO_REASON;
|
||
}
|
||
}
|
||
|
||
static inline void
|
||
uw_update_context (struct _Unwind_Context *context,
|
||
_Unwind_FrameState *fs __attribute__((unused)) )
|
||
{
|
||
context->fc = context->fc->prev;
|
||
}
|
||
|
||
static inline void
|
||
uw_init_context (struct _Unwind_Context *context)
|
||
{
|
||
context->fc = _Unwind_SjLj_GetContext ();
|
||
}
|
||
|
||
/* ??? There appear to be bugs in integrate.c wrt __builtin_longjmp and
|
||
virtual-stack-vars. An inline version of this segfaults on Sparc. */
|
||
#define uw_install_context(CURRENT, TARGET) \
|
||
do \
|
||
{ \
|
||
_Unwind_SjLj_SetContext ((TARGET)->fc); \
|
||
longjmp ((TARGET)->fc->jbuf, 1); \
|
||
} \
|
||
while (0)
|
||
|
||
|
||
static inline _Unwind_Ptr
|
||
uw_identify_context (struct _Unwind_Context *context)
|
||
{
|
||
return (_Unwind_Ptr) context->fc;
|
||
}
|
||
|
||
|
||
/* Play games with unwind symbols so that we can have call frame
|
||
and sjlj symbols in the same shared library. Not that you can
|
||
use them simultaneously... */
|
||
#define _Unwind_RaiseException _Unwind_SjLj_RaiseException
|
||
#define _Unwind_ForcedUnwind _Unwind_SjLj_ForcedUnwind
|
||
#define _Unwind_Resume _Unwind_SjLj_Resume
|
||
|
||
#include "unwind.inc"
|
||
|
||
#endif /* USING_SJLJ_EXCEPTIONS */
|