New files.

2 files changed, 175 insertions, 0 deletions

diff --git a/gdb/tramp-frame.c b/gdb/tramp-frame.c
new file mode 100644
index 00000000000..376ab364653
--- /dev/null
+++ b/gdb/tramp-frame.c
@@ -0,0 +1,111 @@
+/* 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 "trad-frame.h"
+#include "frame-unwind.h"
+#include "gdbcore.h"
+#include "symtab.h"
+#include "objfiles.h"
+#include "target.h"
+
+struct trad_frame_data
+{
+  const struct tramp_frame *tramp_frame;
+};
+
+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 void
+tramp_frame_init (const struct trad_frame *self,
+		  struct frame_info *next_frame,
+		  struct trad_frame_cache *this_cache)
+{
+  CORE_ADDR pc = frame_pc_unwind (next_frame);
+  const struct tramp_frame *tramp = self->trad_data->tramp_frame;
+  tramp->init (tramp, next_frame, this_cache, tramp_frame_start (pc, tramp));
+}
+
+static int
+tramp_frame_sniffer (const struct trad_frame *self,
+		     struct frame_info *next_frame)
+{
+  const struct tramp_frame *tramp = self->trad_data->tramp_frame;
+  CORE_ADDR pc = frame_pc_unwind (next_frame);
+  char *name;
+  /* 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 NULL;
+  /* 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 NULL;
+  /* The problem here is that this code, and tramp_frame_cache, both
+     end up doing a search to find the function start :-(.  */
+  return (tramp_frame_start (pc, tramp) != 0);
+}
+
+void
+tramp_frame_append (struct gdbarch *gdbarch,
+		    const struct tramp_frame *tramp)
+{
+  struct trad_frame_data *trad_data;
+  struct trad_frame *trad;
+
+  trad_data = GDBARCH_OBSTACK_ZALLOC (gdbarch, struct trad_frame_data);
+  trad = GDBARCH_OBSTACK_ZALLOC (gdbarch, struct trad_frame);
+
+  trad_data->tramp_frame = tramp;
+  trad->type = SIGTRAMP_FRAME;
+  trad->trad_data = trad_data;
+  trad->sniffer = tramp_frame_sniffer;
+  trad->init = tramp_frame_init;
+  trad_frame_append (gdbarch, trad);
+}
diff --git a/gdb/tramp-frame.h b/gdb/tramp-frame.h
new file mode 100644
index 00000000000..03eb35b866f
--- /dev/null
+++ b/gdb/tramp-frame.h
@@ -0,0 +1,64 @@
+/* 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 trampline 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 convient 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 containts
+     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 trampolines
+     "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