[deliverable/binutils-gdb.git] / gdb / config / i386 / tm-linux.h

/* Definitions to target GDB to GNU/Linux on 386.
   Copyright 1992, 1993 Free Software Foundation, Inc.

   This file is part of GDB.

   This program 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 of the License, or
   (at your option) any later version.

   This program 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 this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

#ifndef TM_LINUX_H
#define TM_LINUX_H

#define I386_GNULINUX_TARGET
#define HAVE_I387_REGS
#ifdef HAVE_PTRACE_GETXFPREGS
#define HAVE_SSE_REGS
#endif

#include "i386/tm-i386.h"
#include "tm-linux.h"

/* Size of sigcontext, from <asm/sigcontext.h>.  */
#define LINUX_SIGCONTEXT_SIZE (88)

/* Offset to saved PC in sigcontext, from <asm/sigcontext.h>.  */
#define LINUX_SIGCONTEXT_PC_OFFSET (56)

/* Offset to saved SP in sigcontext, from <asm/sigcontext.h>.  */
#define LINUX_SIGCONTEXT_SP_OFFSET (28)

#define LOW_RETURN_REGNUM 0	/* holds low four bytes of result */
#define HIGH_RETURN_REGNUM 2	/* holds high four bytes of result */

/* This should probably move to tm-i386.h.  */
#define TARGET_LONG_DOUBLE_BIT 80

#if defined(HAVE_LONG_DOUBLE) && defined(HOST_I386)
/* The host and target are i386 machines and the compiler supports
   long doubles. Long doubles on the host therefore have the same
   layout as a 387 FPU stack register. */
#define LD_I387

extern int i387_extract_floating (PTR addr, int len, long double *dretptr);
extern int i387_store_floating   (PTR addr, int len, long double val);

#define TARGET_EXTRACT_FLOATING i387_extract_floating
#define TARGET_STORE_FLOATING   i387_store_floating

#define TARGET_ANALYZE_FLOATING					\
  do								\
    {								\
      unsigned expon;						\
								\
      low = extract_unsigned_integer (valaddr, 4);		\
      high = extract_unsigned_integer (valaddr + 4, 4);		\
      expon = extract_unsigned_integer (valaddr + 8, 2);	\
								\
      nonnegative = ((expon & 0x8000) == 0);			\
      is_nan = ((expon & 0x7fff) == 0x7fff)			\
	&& ((high & 0x80000000) == 0x80000000)			\
	&& (((high & 0x7fffffff) | low) != 0);			\
    }								\
  while (0)

#undef REGISTER_CONVERT_TO_VIRTUAL
#define REGISTER_CONVERT_TO_VIRTUAL(REGNUM,TYPE,FROM,TO)	\
{								\
  long double val = *((long double *)FROM);			\
  store_floating ((TO), TYPE_LENGTH (TYPE), val);		\
}

#undef REGISTER_CONVERT_TO_RAW
#define REGISTER_CONVERT_TO_RAW(TYPE,REGNUM,FROM,TO)			\
{									\
  long double val = extract_floating ((FROM), TYPE_LENGTH (TYPE));	\
  *((long double *)TO) = val;						\
}

/* Return the GDB type object for the "standard" data type
   of data in register N.  */
#undef REGISTER_VIRTUAL_TYPE
#define REGISTER_VIRTUAL_TYPE(N)				\
  (((N) == PC_REGNUM || (N) == FP_REGNUM || (N) == SP_REGNUM)	\
   ? lookup_pointer_type (builtin_type_void)			\
   : IS_FP_REGNUM(N) ? builtin_type_long_double			\
   : IS_SSE_REGNUM(N) ? builtin_type_v4sf			\
   : builtin_type_int)

#endif

/* The following works around a problem with /usr/include/sys/procfs.h  */
#define sys_quotactl 1

/* When the i386 Linux kernel calls a signal handler, the return
   address points to a bit of code on the stack.  These definitions
   are used to identify this bit of code as a signal trampoline in
   order to support backtracing through calls to signal handlers.  */

#define I386_LINUX_SIGTRAMP
#define IN_SIGTRAMP(pc, name) ((name) == NULL && i386_linux_sigtramp (pc))

extern int i386_linux_sigtramp PARAMS ((CORE_ADDR));

/* We need our own version of sigtramp_saved_pc to get the saved PC in
   a sigtramp routine.  */

#define sigtramp_saved_pc i386_linux_sigtramp_saved_pc
extern CORE_ADDR i386_linux_sigtramp_saved_pc PARAMS ((struct frame_info *));

/* Signal trampolines don't have a meaningful frame.  As in tm-i386.h,
   the frame pointer value we use is actually the frame pointer of the
   calling frame--that is, the frame which was in progress when the
   signal trampoline was entered.  gdb mostly treats this frame
   pointer value as a magic cookie.  We detect the case of a signal
   trampoline by looking at the SIGNAL_HANDLER_CALLER field, which is
   set based on IN_SIGTRAMP.

   When a signal trampoline is invoked from a frameless function, we
   essentially have two frameless functions in a row.  In this case,
   we use the same magic cookie for three frames in a row.  We detect
   this case by seeing whether the next frame has
   SIGNAL_HANDLER_CALLER set, and, if it does, checking whether the
   current frame is actually frameless.  In this case, we need to get
   the PC by looking at the SP register value stored in the signal
   context.

   This should work in most cases except in horrible situations where
   a signal occurs just as we enter a function but before the frame
   has been set up.  */

#define FRAMELESS_SIGNAL(FRAME)					\
  ((FRAME)->next != NULL					\
   && (FRAME)->next->signal_handler_caller			\
   && frameless_look_for_prologue (FRAME))

#undef FRAME_CHAIN
#define FRAME_CHAIN(FRAME)					\
  ((FRAME)->signal_handler_caller				\
   ? (FRAME)->frame						\
    : (FRAMELESS_SIGNAL (FRAME)					\
       ? (FRAME)->frame						\
       : (!inside_entry_file ((FRAME)->pc)			\
	  ? read_memory_integer ((FRAME)->frame, 4)		\
	  : 0)))

#undef FRAME_SAVED_PC
#define FRAME_SAVED_PC(FRAME)					\
  ((FRAME)->signal_handler_caller				\
   ? sigtramp_saved_pc (FRAME)					\
   : (FRAMELESS_SIGNAL (FRAME)					\
      ? read_memory_integer (i386_linux_sigtramp_saved_sp ((FRAME)->next), 4) \
      : read_memory_integer ((FRAME)->frame + 4, 4)))

extern CORE_ADDR i386_linux_sigtramp_saved_sp PARAMS ((struct frame_info *));

/* When we call a function in a shared library, and the PLT sends us
   into the dynamic linker to find the function's real address, we
   need to skip over the dynamic linker call.  This function decides
   when to skip, and where to skip to.  See the comments for
   SKIP_SOLIB_RESOLVER at the top of infrun.c.  */
#define SKIP_SOLIB_RESOLVER i386_linux_skip_solib_resolver
extern CORE_ADDR i386_linux_skip_solib_resolver (CORE_ADDR pc);

/* N_FUN symbols in shared libaries have 0 for their values and need
   to be relocated. */
#define SOFUN_ADDRESS_MAYBE_MISSING

#endif /* #ifndef TM_LINUX_H */
Commit	Line	Data
c906108c SS	1	/* Definitions to target GDB to GNU/Linux on 386.
	2	Copyright 1992, 1993 Free Software Foundation, Inc.
	3
c5aa993b	4	This file is part of GDB.
c906108c	5
c5aa993b JM	6	This program is free software; you can redistribute it and/or modify
	7	it under the terms of the GNU General Public License as published by
	8	the Free Software Foundation; either version 2 of the License, or
	9	(at your option) any later version.
c906108c	10
c5aa993b JM	11	This program is distributed in the hope that it will be useful,
	12	but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	GNU General Public License for more details.
c906108c	15
c5aa993b JM	16	You should have received a copy of the GNU General Public License
	17	along with this program; if not, write to the Free Software
	18	Foundation, Inc., 59 Temple Place - Suite 330,
	19	Boston, MA 02111-1307, USA. */
c906108c SS	20
	21	#ifndef TM_LINUX_H
	22	#define TM_LINUX_H
	23
d4f3574e	24	#define I386_GNULINUX_TARGET
917317f4	25	#define HAVE_I387_REGS
5c44784c JM	26	#ifdef HAVE_PTRACE_GETXFPREGS
	27	#define HAVE_SSE_REGS
	28	#endif
c906108c SS	29
c906108c SS	30	#include "i386/tm-i386.h"
c2d11a7d	31	#include "tm-linux.h"
c906108c	32
a0b3c4fd JM	33	/* Size of sigcontext, from <asm/sigcontext.h>. */
	34	#define LINUX_SIGCONTEXT_SIZE (88)
	35
	36	/* Offset to saved PC in sigcontext, from <asm/sigcontext.h>. */
	37	#define LINUX_SIGCONTEXT_PC_OFFSET (56)
	38
	39	/* Offset to saved SP in sigcontext, from <asm/sigcontext.h>. */
	40	#define LINUX_SIGCONTEXT_SP_OFFSET (28)
c906108c	41
d4f3574e SS	42	#define LOW_RETURN_REGNUM 0 /* holds low four bytes of result */
	43	#define HIGH_RETURN_REGNUM 2 /* holds high four bytes of result */
	44
917317f4 JM	45	/* This should probably move to tm-i386.h. */
917317f4 JM	46	#define TARGET_LONG_DOUBLE_BIT 80
d4f3574e SS	47
	48	#if defined(HAVE_LONG_DOUBLE) && defined(HOST_I386)
	49	/* The host and target are i386 machines and the compiler supports
	50	long doubles. Long doubles on the host therefore have the same
	51	layout as a 387 FPU stack register. */
	52	#define LD_I387
d4f3574e	53
d4f3574e SS	54	extern int i387_extract_floating (PTR addr, int len, long double *dretptr);
	55	extern int i387_store_floating (PTR addr, int len, long double val);
	56
	57	#define TARGET_EXTRACT_FLOATING i387_extract_floating
	58	#define TARGET_STORE_FLOATING i387_store_floating
	59
	60	#define TARGET_ANALYZE_FLOATING \
	61	do \
	62	{ \
	63	unsigned expon; \
	64	\
	65	low = extract_unsigned_integer (valaddr, 4); \
	66	high = extract_unsigned_integer (valaddr + 4, 4); \
	67	expon = extract_unsigned_integer (valaddr + 8, 2); \
	68	\
	69	nonnegative = ((expon & 0x8000) == 0); \
	70	is_nan = ((expon & 0x7fff) == 0x7fff) \
	71	&& ((high & 0x80000000) == 0x80000000) \
	72	&& (((high & 0x7fffffff) \| low) != 0); \
	73	} \
	74	while (0)
d4f3574e	75
917317f4 JM	76	#undef REGISTER_CONVERT_TO_VIRTUAL
	77	#define REGISTER_CONVERT_TO_VIRTUAL(REGNUM,TYPE,FROM,TO) \
	78	{ \
	79	long double val = ((long double )FROM); \
	80	store_floating ((TO), TYPE_LENGTH (TYPE), val); \
d4f3574e	81	}
d4f3574e	82
917317f4 JM	83	#undef REGISTER_CONVERT_TO_RAW
	84	#define REGISTER_CONVERT_TO_RAW(TYPE,REGNUM,FROM,TO) \
	85	{ \
	86	long double val = extract_floating ((FROM), TYPE_LENGTH (TYPE)); \
	87	((long double )TO) = val; \
d4f3574e	88	}
d4f3574e SS	89
	90	/* Return the GDB type object for the "standard" data type
	91	of data in register N. */
917317f4	92	#undef REGISTER_VIRTUAL_TYPE
5c44784c JM	93	#define REGISTER_VIRTUAL_TYPE(N) \
	94	(((N) == PC_REGNUM \|\| (N) == FP_REGNUM \|\| (N) == SP_REGNUM) \
	95	? lookup_pointer_type (builtin_type_void) \
	96	: IS_FP_REGNUM(N) ? builtin_type_long_double \
	97	: IS_SSE_REGNUM(N) ? builtin_type_v4sf \
	98	: builtin_type_int)
d4f3574e	99
d4f3574e SS	100	#endif
d4f3574e SS	101
c906108c SS	102	/* The following works around a problem with /usr/include/sys/procfs.h */
	103	#define sys_quotactl 1
	104
a0b3c4fd JM	105	/* When the i386 Linux kernel calls a signal handler, the return
	106	address points to a bit of code on the stack. These definitions
	107	are used to identify this bit of code as a signal trampoline in
	108	order to support backtracing through calls to signal handlers. */
	109
	110	#define I386_LINUX_SIGTRAMP
	111	#define IN_SIGTRAMP(pc, name) ((name) == NULL && i386_linux_sigtramp (pc))
	112
	113	extern int i386_linux_sigtramp PARAMS ((CORE_ADDR));
	114
	115	/* We need our own version of sigtramp_saved_pc to get the saved PC in
	116	a sigtramp routine. */
	117
	118	#define sigtramp_saved_pc i386_linux_sigtramp_saved_pc
	119	extern CORE_ADDR i386_linux_sigtramp_saved_pc PARAMS ((struct frame_info *));
	120
	121	/* Signal trampolines don't have a meaningful frame. As in tm-i386.h,
	122	the frame pointer value we use is actually the frame pointer of the
	123	calling frame--that is, the frame which was in progress when the
	124	signal trampoline was entered. gdb mostly treats this frame
	125	pointer value as a magic cookie. We detect the case of a signal
	126	trampoline by looking at the SIGNAL_HANDLER_CALLER field, which is
	127	set based on IN_SIGTRAMP.
	128
	129	When a signal trampoline is invoked from a frameless function, we
	130	essentially have two frameless functions in a row. In this case,
	131	we use the same magic cookie for three frames in a row. We detect
	132	this case by seeing whether the next frame has
	133	SIGNAL_HANDLER_CALLER set, and, if it does, checking whether the
	134	current frame is actually frameless. In this case, we need to get
	135	the PC by looking at the SP register value stored in the signal
	136	context.
	137
	138	This should work in most cases except in horrible situations where
	139	a signal occurs just as we enter a function but before the frame
	140	has been set up. */
	141
	142	#define FRAMELESS_SIGNAL(FRAME) \
	143	((FRAME)->next != NULL \
	144	&& (FRAME)->next->signal_handler_caller \
	145	&& frameless_look_for_prologue (FRAME))
	146
	147	#undef FRAME_CHAIN
	148	#define FRAME_CHAIN(FRAME) \
	149	((FRAME)->signal_handler_caller \
	150	? (FRAME)->frame \
	151	: (FRAMELESS_SIGNAL (FRAME) \
	152	? (FRAME)->frame \
	153	: (!inside_entry_file ((FRAME)->pc) \
	154	? read_memory_integer ((FRAME)->frame, 4) \
	155	: 0)))
	156
	157	#undef FRAME_SAVED_PC
	158	#define FRAME_SAVED_PC(FRAME) \
	159	((FRAME)->signal_handler_caller \
	160	? sigtramp_saved_pc (FRAME) \
	161	: (FRAMELESS_SIGNAL (FRAME) \
	162	? read_memory_integer (i386_linux_sigtramp_saved_sp ((FRAME)->next), 4) \
	163	: read_memory_integer ((FRAME)->frame + 4, 4)))
	164
	165	extern CORE_ADDR i386_linux_sigtramp_saved_sp PARAMS ((struct frame_info *));
	166
d4f3574e SS	167	/* When we call a function in a shared library, and the PLT sends us
	168	into the dynamic linker to find the function's real address, we
	169	need to skip over the dynamic linker call. This function decides
	170	when to skip, and where to skip to. See the comments for
	171	SKIP_SOLIB_RESOLVER at the top of infrun.c. */
	172	#define SKIP_SOLIB_RESOLVER i386_linux_skip_solib_resolver
	173	extern CORE_ADDR i386_linux_skip_solib_resolver (CORE_ADDR pc);
	174
	175	/* N_FUN symbols in shared libaries have 0 for their values and need
	176	to be relocated. */
	177	#define SOFUN_ADDRESS_MAYBE_MISSING
	178
c5aa993b	179	#endif /* #ifndef TM_LINUX_H */