--- /dev/null
+/* Signal trampoline unwinder, for GDB the GNU Debugger.
+
+ Copyright 2004 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. */
+
+#include "defs.h"
+#include "tramp-frame.h"
+#include "frame-unwind.h"
+#include "gdbcore.h"
+#include "symtab.h"
+#include "objfiles.h"
+#include "target.h"
+#include "trad-frame.h"
+#include "frame-base.h"
+
+struct frame_data
+{
+ const struct tramp_frame *tramp_frame;
+};
+
+struct tramp_frame_cache
+{
+ CORE_ADDR func;
+ const struct tramp_frame *tramp_frame;
+ struct trad_frame_cache *trad_cache;
+};
+
+static struct trad_frame_cache *
+tramp_frame_cache (struct frame_info *next_frame,
+ void **this_cache)
+{
+ CORE_ADDR pc = frame_pc_unwind (next_frame);
+ struct tramp_frame_cache *tramp_cache = (*this_cache);
+ if (tramp_cache->trad_cache == NULL)
+ {
+ tramp_cache->trad_cache = trad_frame_cache_zalloc (next_frame);
+ tramp_cache->tramp_frame->init (tramp_cache->tramp_frame,
+ next_frame,
+ tramp_cache->trad_cache,
+ tramp_cache->func);
+ }
+ return tramp_cache->trad_cache;
+}
+
+static void
+tramp_frame_this_id (struct frame_info *next_frame,
+ void **this_cache,
+ struct frame_id *this_id)
+{
+ struct trad_frame_cache *trad_cache
+ = tramp_frame_cache (next_frame, this_cache);
+ trad_frame_get_id (trad_cache, this_id);
+}
+
+static void
+tramp_frame_prev_register (struct frame_info *next_frame,
+ void **this_cache,
+ int prev_regnum,
+ int *optimizedp,
+ enum lval_type * lvalp,
+ CORE_ADDR *addrp,
+ int *realnump, void *valuep)
+{
+ struct trad_frame_cache *trad_cache
+ = tramp_frame_cache (next_frame, this_cache);
+ trad_frame_get_register (trad_cache, next_frame, prev_regnum, optimizedp,
+ lvalp, addrp, realnump, valuep);
+}
+
+static CORE_ADDR
+tramp_frame_start (CORE_ADDR pc, const struct tramp_frame *tramp)
+{
+ int ti;
+ /* Search through the trampoline for one that matches the
+ instruction sequence around PC. */
+ for (ti = 0; tramp->insn[ti] != 0; ti++)
+ {
+ CORE_ADDR func = pc - tramp->insn_size * ti;
+ int i;
+ for (i = 0; 1; i++)
+ {
+ bfd_byte buf[sizeof (LONGEST)];
+ CORE_ADDR insn;
+ if (tramp->insn[i] == 0)
+ return func;
+ if (target_read_memory (func + i * tramp->insn_size, buf,
+ tramp->insn_size) != 0)
+ break;
+ insn = extract_unsigned_integer (buf, tramp->insn_size);
+ if (tramp->insn[i] != insn)
+ break;
+ }
+ }
+ /* Trampoline doesn't match. */
+ return 0;
+}
+
+static int
+tramp_frame_sniffer (const struct frame_unwind *self,
+ struct frame_info *next_frame,
+ void **this_cache)
+{
+ const struct tramp_frame *tramp = self->unwind_data->tramp_frame;
+ CORE_ADDR pc = frame_pc_unwind (next_frame);
+ CORE_ADDR func;
+ char *name;
+ struct tramp_frame_cache *tramp_cache;
+
+ /* If the function has a valid symbol name, it isn't a
+ trampoline. */
+ find_pc_partial_function (pc, &name, NULL, NULL);
+ if (name != NULL)
+ return 0;
+ /* If the function lives in a valid section (even without a starting
+ point) it isn't a trampoline. */
+ if (find_pc_section (pc) != NULL)
+ return 0;
+ /* Finally, check that the trampoline matches at PC. */
+ func = tramp_frame_start (pc, tramp);
+ if (func == 0)
+ return 0;
+ tramp_cache = FRAME_OBSTACK_ZALLOC (struct tramp_frame_cache);
+ tramp_cache->func = func;
+ tramp_cache->tramp_frame = tramp;
+ (*this_cache) = tramp_cache;
+ return 1;
+}
+
+void
+tramp_frame_append (struct gdbarch *gdbarch,
+ const struct tramp_frame *tramp_frame)
+{
+ struct frame_data *data;
+ struct frame_unwind *unwinder;
+
+ data = GDBARCH_OBSTACK_ZALLOC (gdbarch, struct frame_data);
+ unwinder = GDBARCH_OBSTACK_ZALLOC (gdbarch, struct frame_unwind);
+
+ data->tramp_frame = tramp_frame;
+ unwinder->type = SIGTRAMP_FRAME;
+ unwinder->unwind_data = data;
+ unwinder->sniffer = tramp_frame_sniffer;
+ unwinder->this_id = tramp_frame_this_id;
+ unwinder->prev_register = tramp_frame_prev_register;
+ frame_unwind_register_unwinder (gdbarch, unwinder);
+}
--- /dev/null
+/* Signal trampoline unwinder, for GDB the GNU Debugger.
+
+ Copyright 2004 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 TRAMP_FRAME_H
+#define TRAMP_FRAME_H
+
+struct trad_frame;
+struct frame_info;
+struct trad_frame_cache;
+
+/* A trampoline consists of a small sequence of instructions placed at
+ an unspecified location in the inferior's address space. The only
+ identifying attribute of the trampoline's address is that it does
+ not fall inside an object file's section.
+
+ The only way to identify a trampoline is to perform a brute force
+ examination of the instructions at and around the PC.
+
+ This module provides a convent interface for performing that
+ operation. */
+
+/* A trampoline descriptor. */
+
+struct tramp_frame
+{
+ /* The trampoline's entire instruction sequence. Search for this in
+ the inferior at or around the frame's PC. It is assumed that the
+ PC is INSN_SIZE aligned, and that each element of TRAMP contains
+ one INSN_SIZE instruction. It is also assumed that TRAMP[0]
+ contains the first instruction of the trampoline and hence the
+ address of the instruction matching TRAMP[0] is the trampoline's
+ "func" address. */
+ int insn_size;
+ ULONGEST insn[8];
+ /* Initialize a trad-frame cache corresponding to the tramp-frame.
+ FUNC is the address of the instruction TRAMP[0] in memory. */
+ void (*init) (const struct tramp_frame *self,
+ struct frame_info *next_frame,
+ struct trad_frame_cache *this_cache,
+ CORE_ADDR func);
+};
+
+void tramp_frame_append (struct gdbarch *gdbarch,
+ const struct tramp_frame *tramp);
+
+#endif
projects / binutils-gdb.git / commitdiff