/* Print NS 32000 instructions for GDB, the GNU debugger.
- Copyright 1986, 1988, 1991, 1992, 1994, 1995
+ Copyright 1986, 1988, 1991, 1992, 1994, 1995, 1998, 1999, 2000, 2001
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. */
#include "defs.h"
+#include "frame.h"
+#include "gdbcore.h"
+
+static int sign_extend (int value, int bits);
void
-_initialize_ns32k_tdep ()
+_initialize_ns32k_tdep (void)
{
tm_print_insn = print_insn_ns32k;
}
+
+/* Advance PC across any function entry prologue instructions
+ to reach some "real" code. */
+
+CORE_ADDR
+umax_skip_prologue (CORE_ADDR pc)
+{
+ register unsigned char op = read_memory_integer (pc, 1);
+ if (op == 0x82)
+ {
+ op = read_memory_integer (pc + 2, 1);
+ if ((op & 0x80) == 0)
+ pc += 3;
+ else if ((op & 0xc0) == 0x80)
+ pc += 4;
+ else
+ pc += 6;
+ }
+ return pc;
+}
+
+/* Return number of args passed to a frame.
+ Can return -1, meaning no way to tell.
+ Encore's C compiler often reuses same area on stack for args,
+ so this will often not work properly. If the arg names
+ are known, it's likely most of them will be printed. */
+
+int
+umax_frame_num_args (struct frame_info *fi)
+{
+ int numargs;
+ CORE_ADDR pc;
+ CORE_ADDR enter_addr;
+ unsigned int insn;
+ unsigned int addr_mode;
+ int width;
+
+ numargs = -1;
+ enter_addr = ns32k_get_enter_addr ((fi)->pc);
+ if (enter_addr > 0)
+ {
+ pc = ((enter_addr == 1)
+ ? SAVED_PC_AFTER_CALL (fi)
+ : FRAME_SAVED_PC (fi));
+ insn = read_memory_integer (pc, 2);
+ addr_mode = (insn >> 11) & 0x1f;
+ insn = insn & 0x7ff;
+ if ((insn & 0x7fc) == 0x57c
+ && addr_mode == 0x14) /* immediate */
+ {
+ if (insn == 0x57c) /* adjspb */
+ width = 1;
+ else if (insn == 0x57d) /* adjspw */
+ width = 2;
+ else if (insn == 0x57f) /* adjspd */
+ width = 4;
+ else
+ internal_error (__FILE__, __LINE__, "bad else");
+ numargs = read_memory_integer (pc + 2, width);
+ if (width > 1)
+ flip_bytes (&numargs, width);
+ numargs = -sign_extend (numargs, width * 8) / 4;
+ }
+ }
+ return numargs;
+}
+
+static int
+sign_extend (int value, int bits)
+{
+ value = value & ((1 << bits) - 1);
+ return (value & (1 << (bits - 1))
+ ? value | (~((1 << bits) - 1))
+ : value);
+}
+
+void
+flip_bytes (void *p, int count)
+{
+ char tmp;
+ char *ptr = 0;
+
+ while (count > 0)
+ {
+ tmp = *ptr;
+ ptr[0] = ptr[count - 1];
+ ptr[count - 1] = tmp;
+ ptr++;
+ count -= 2;
+ }
+}
+
+/* Return the number of locals in the current frame given a pc
+ pointing to the enter instruction. This is used in the macro
+ FRAME_FIND_SAVED_REGS. */
+
+int
+ns32k_localcount (CORE_ADDR enter_pc)
+{
+ unsigned char localtype;
+ int localcount;
+
+ localtype = read_memory_integer (enter_pc + 2, 1);
+ if ((localtype & 0x80) == 0)
+ localcount = localtype;
+ else if ((localtype & 0xc0) == 0x80)
+ localcount = (((localtype & 0x3f) << 8)
+ | (read_memory_integer (enter_pc + 3, 1) & 0xff));
+ else
+ localcount = (((localtype & 0x3f) << 24)
+ | ((read_memory_integer (enter_pc + 3, 1) & 0xff) << 16)
+ | ((read_memory_integer (enter_pc + 4, 1) & 0xff) << 8)
+ | (read_memory_integer (enter_pc + 5, 1) & 0xff));
+ return localcount;
+}
+
+
+/* Nonzero if instruction at PC is a return instruction. */
+
+static int
+ns32k_about_to_return (CORE_ADDR pc)
+{
+ return (read_memory_integer (pc, 1) == 0x12);
+}
+
+
+/*
+ * Get the address of the enter opcode for the function
+ * containing PC, if there is an enter for the function,
+ * and if the pc is between the enter and exit.
+ * Returns positive address if pc is between enter/exit,
+ * 1 if pc before enter or after exit, 0 otherwise.
+ */
+
+CORE_ADDR
+ns32k_get_enter_addr (CORE_ADDR pc)
+{
+ CORE_ADDR enter_addr;
+ unsigned char op;
+
+ if (pc == 0)
+ return 0;
+
+ if (ns32k_about_to_return (pc))
+ return 1; /* after exit */
+
+ enter_addr = get_pc_function_start (pc);
+
+ if (pc == enter_addr)
+ return 1; /* before enter */
+
+ op = read_memory_integer (enter_addr, 1);
+
+ if (op != 0x82)
+ return 0; /* function has no enter/exit */
+
+ return enter_addr; /* pc is between enter and exit */
+}
projects / deliverable / binutils-gdb.git / blobdiff