Initial creation of sourceware repository

gdb/i386ly-tdep.c

@@ -0,0 +1,43 @@
+/* Target-dependent code for Intel 386 running LynxOS.
+   Copyright 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.  */
+
+#include "defs.h"
+#include "inferior.h"
+#include "target.h"
+#include "gdbcore.h"
+
+/* Return the PC of the caller from the call frame.  Assumes the subr prologue
+   has already been executed, and the frame pointer setup.  If this is the
+   outermost frame, we check to see if we are in a system call by examining the
+   previous instruction.  If so, then the return PC is actually at SP+4 because
+   system calls use a different calling sequence.  */
+
+CORE_ADDR
+i386lynx_saved_pc_after_call (frame)
+     struct frame_info *frame;
+{
+  char opcode[7];
+  static const unsigned char call_inst[] = {0x9a, 0, 0, 0, 0, 8, 0}; /* lcall 0x8,0x0 */
+
+  read_memory (frame->pc - 7, opcode, 7);
+  if (memcmp (opcode, call_inst, 7) == 0)
+    return read_memory_integer (read_register (SP_REGNUM) + 4, 4);
+
+  return read_memory_integer (read_register (SP_REGNUM), 4);
+}