/* Definitions to target GDB to GNU/Linux on 386.
Copyright 1992, 1993 Free Software Foundation, Inc.
-This file is part of GDB.
+ 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 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.
+ 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. */
+ 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
-/* FIXME: If nothing else gets added to this file, it could be removed
- and configure could just use tm-i386.h instead. -fnf */
+#define I386_GNULINUX_TARGET
+#define HAVE_I387_REGS
#include "i386/tm-i386.h"
-/* Offset to saved PC in sigcontext, from <linux/signal.h>. */
-#define SIGCONTEXT_PC_OFFSET 38
+/* 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)
/* We need this file for the SOLIB_TRAMPOLINE stuff. */
#include "tm-sysv4.h"
+#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) \
+ (IS_FP_REGNUM (N) ? builtin_type_long_double : builtin_type_int)
+
+#endif
+
/* The following works around a problem with /usr/include/sys/procfs.h */
#define sys_quotactl 1
-#endif /* #ifndef TM_LINUX_H */
+/* 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 *));
+
+/* Some versions of Linux have real-time signal support in the C library, and
+ some don't. We have to include this file to find out. */
+#include <signal.h>
+
+#ifdef __SIGRTMIN
+#define REALTIME_LO __SIGRTMIN
+#define REALTIME_HI (__SIGRTMAX + 1)
+#else
+#define REALTIME_LO 32
+#define REALTIME_HI 64
+#endif
+
+/* 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 */
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