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

/* Definitions to target GDB to GNU/Linux on 386.
   Copyright 1992, 1993, 2000 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_GETFPXREGS
#define HAVE_SSE_REGS
#endif

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

/* Use target_specific function to define link map offsets.  */
extern struct link_map_offsets *i386_linux_svr4_fetch_link_map_offsets (void);
#define SVR4_FETCH_LINK_MAP_OFFSETS() i386_linux_svr4_fetch_link_map_offsets ()

/* FIXME: kettenis/2000-03-26: We should get rid of this last piece of
   Linux-specific `long double'-support code, probably by adding code
   to valprint.c:print_floating() to recognize various extended
   floating-point formats.  */

#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 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)

#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 IN_SIGTRAMP(pc, name) i386_linux_in_sigtramp (pc, name)
extern int i386_linux_in_sigtramp (CORE_ADDR, char *);

/* 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 (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 (struct frame_info *);

#undef SAVED_PC_AFTER_CALL
#define SAVED_PC_AFTER_CALL(frame) i386_linux_saved_pc_after_call (frame)
extern CORE_ADDR i386_linux_saved_pc_after_call (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
\f

/* Support for longjmp.  */

/* Details about jmp_buf.  It's supposed to be an array of integers.  */

#define JB_ELEMENT_SIZE 4	/* Size of elements in jmp_buf.  */
#define JB_PC		5	/* Array index of saved PC.  */

/* Figure out where the longjmp will land.  Slurp the args out of the
   stack.  We expect the first arg to be a pointer to the jmp_buf
   structure from which we extract the pc (JB_PC) that we will land
   at.  The pc is copied into ADDR.  This routine returns true on
   success.  */

#define GET_LONGJMP_TARGET(addr) get_longjmp_target (addr)
extern int get_longjmp_target (CORE_ADDR *addr);

#endif /* #ifndef TM_LINUX_H */
Commit	Line	Data
c906108c	1	/* Definitions to target GDB to GNU/Linux on 386.
6ce2ac0b	2	Copyright 1992, 1993, 2000 Free Software Foundation, Inc.
c906108c	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
6ce2ac0b	26	#ifdef HAVE_PTRACE_GETFPXREGS
5c44784c JM	27	#define HAVE_SSE_REGS
5c44784c JM	28	#endif
c906108c SS	29
c906108c SS	30	#include "i386/tm-i386.h"
c2d11a7d	31	#include "tm-linux.h"
c906108c	32
1a8629c7 MS	33	/* Use target_specific function to define link map offsets. */
	34	extern struct link_map_offsets *i386_linux_svr4_fetch_link_map_offsets (void);
	35	#define SVR4_FETCH_LINK_MAP_OFFSETS() i386_linux_svr4_fetch_link_map_offsets ()
	36
ac27f131 MK	37	/* FIXME: kettenis/2000-03-26: We should get rid of this last piece of
	38	Linux-specific `long double'-support code, probably by adding code
	39	to valprint.c:print_floating() to recognize various extended
	40	floating-point formats. */
d4f3574e SS	41
	42	#if defined(HAVE_LONG_DOUBLE) && defined(HOST_I386)
	43	/* The host and target are i386 machines and the compiler supports
	44	long doubles. Long doubles on the host therefore have the same
	45	layout as a 387 FPU stack register. */
d4f3574e SS	46
	47	#define TARGET_ANALYZE_FLOATING \
	48	do \
	49	{ \
	50	unsigned expon; \
	51	\
	52	low = extract_unsigned_integer (valaddr, 4); \
	53	high = extract_unsigned_integer (valaddr + 4, 4); \
	54	expon = extract_unsigned_integer (valaddr + 8, 2); \
	55	\
	56	nonnegative = ((expon & 0x8000) == 0); \
	57	is_nan = ((expon & 0x7fff) == 0x7fff) \
	58	&& ((high & 0x80000000) == 0x80000000) \
	59	&& (((high & 0x7fffffff) \| low) != 0); \
	60	} \
	61	while (0)
d4f3574e	62
d4f3574e SS	63	#endif
d4f3574e SS	64
c906108c SS	65	/* The following works around a problem with /usr/include/sys/procfs.h */
	66	#define sys_quotactl 1
	67
a0b3c4fd JM	68	/* When the i386 Linux kernel calls a signal handler, the return
	69	address points to a bit of code on the stack. These definitions
	70	are used to identify this bit of code as a signal trampoline in
	71	order to support backtracing through calls to signal handlers. */
	72
45a816d9 MK	73	#define IN_SIGTRAMP(pc, name) i386_linux_in_sigtramp (pc, name)
45a816d9 MK	74	extern int i386_linux_in_sigtramp (CORE_ADDR, char *);
a0b3c4fd JM	75
	76	/* We need our own version of sigtramp_saved_pc to get the saved PC in
	77	a sigtramp routine. */
	78
	79	#define sigtramp_saved_pc i386_linux_sigtramp_saved_pc
45a816d9	80	extern CORE_ADDR i386_linux_sigtramp_saved_pc (struct frame_info *);
a0b3c4fd JM	81
	82	/* Signal trampolines don't have a meaningful frame. As in tm-i386.h,
	83	the frame pointer value we use is actually the frame pointer of the
	84	calling frame--that is, the frame which was in progress when the
	85	signal trampoline was entered. gdb mostly treats this frame
	86	pointer value as a magic cookie. We detect the case of a signal
	87	trampoline by looking at the SIGNAL_HANDLER_CALLER field, which is
	88	set based on IN_SIGTRAMP.
	89
	90	When a signal trampoline is invoked from a frameless function, we
	91	essentially have two frameless functions in a row. In this case,
	92	we use the same magic cookie for three frames in a row. We detect
	93	this case by seeing whether the next frame has
	94	SIGNAL_HANDLER_CALLER set, and, if it does, checking whether the
	95	current frame is actually frameless. In this case, we need to get
	96	the PC by looking at the SP register value stored in the signal
	97	context.
	98
	99	This should work in most cases except in horrible situations where
	100	a signal occurs just as we enter a function but before the frame
	101	has been set up. */
	102
	103	#define FRAMELESS_SIGNAL(FRAME) \
	104	((FRAME)->next != NULL \
	105	&& (FRAME)->next->signal_handler_caller \
	106	&& frameless_look_for_prologue (FRAME))
	107
	108	#undef FRAME_CHAIN
	109	#define FRAME_CHAIN(FRAME) \
	110	((FRAME)->signal_handler_caller \
	111	? (FRAME)->frame \
	112	: (FRAMELESS_SIGNAL (FRAME) \
	113	? (FRAME)->frame \
	114	: (!inside_entry_file ((FRAME)->pc) \
	115	? read_memory_integer ((FRAME)->frame, 4) \
	116	: 0)))
	117
	118	#undef FRAME_SAVED_PC
	119	#define FRAME_SAVED_PC(FRAME) \
	120	((FRAME)->signal_handler_caller \
	121	? sigtramp_saved_pc (FRAME) \
	122	: (FRAMELESS_SIGNAL (FRAME) \
	123	? read_memory_integer (i386_linux_sigtramp_saved_sp ((FRAME)->next), 4) \
	124	: read_memory_integer ((FRAME)->frame + 4, 4)))
	125
45a816d9	126	extern CORE_ADDR i386_linux_sigtramp_saved_sp (struct frame_info *);
a0b3c4fd	127
4cc24188 MK	128	#undef SAVED_PC_AFTER_CALL
	129	#define SAVED_PC_AFTER_CALL(frame) i386_linux_saved_pc_after_call (frame)
	130	extern CORE_ADDR i386_linux_saved_pc_after_call (struct frame_info *);
	131
d4f3574e SS	132	/* When we call a function in a shared library, and the PLT sends us
	133	into the dynamic linker to find the function's real address, we
	134	need to skip over the dynamic linker call. This function decides
	135	when to skip, and where to skip to. See the comments for
	136	SKIP_SOLIB_RESOLVER at the top of infrun.c. */
	137	#define SKIP_SOLIB_RESOLVER i386_linux_skip_solib_resolver
	138	extern CORE_ADDR i386_linux_skip_solib_resolver (CORE_ADDR pc);
	139
	140	/* N_FUN symbols in shared libaries have 0 for their values and need
	141	to be relocated. */
	142	#define SOFUN_ADDRESS_MAYBE_MISSING
f19ebbbc MK	143	\f
	144
	145	/* Support for longjmp. */
	146
	147	/* Details about jmp_buf. It's supposed to be an array of integers. */
	148
	149	#define JB_ELEMENT_SIZE 4 /* Size of elements in jmp_buf. */
	150	#define JB_PC 5 /* Array index of saved PC. */
	151
	152	/* Figure out where the longjmp will land. Slurp the args out of the
	153	stack. We expect the first arg to be a pointer to the jmp_buf
	154	structure from which we extract the pc (JB_PC) that we will land
	155	at. The pc is copied into ADDR. This routine returns true on
	156	success. */
	157
	158	#define GET_LONGJMP_TARGET(addr) get_longjmp_target (addr)
	159	extern int get_longjmp_target (CORE_ADDR *addr);
d4f3574e	160
c5aa993b	161	#endif /* #ifndef TM_LINUX_H */