893 lines
24 KiB
C
893 lines
24 KiB
C
/* Target-dependent code for the Matsushita MN10200 for GDB, the GNU debugger.
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Copyright 1997, 2001 Free Software Foundation, Inc.
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This file is part of GDB.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 59 Temple Place - Suite 330,
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Boston, MA 02111-1307, USA. */
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#include "defs.h"
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#include "frame.h"
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#include "inferior.h"
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#include "obstack.h"
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#include "target.h"
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#include "value.h"
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#include "bfd.h"
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#include "gdb_string.h"
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#include "gdbcore.h"
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#include "symfile.h"
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#include "regcache.h"
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/* Should call_function allocate stack space for a struct return? */
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int
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mn10200_use_struct_convention (int gcc_p, struct type *type)
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{
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return (TYPE_NFIELDS (type) > 1 || TYPE_LENGTH (type) > 8);
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}
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/* *INDENT-OFF* */
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/* The main purpose of this file is dealing with prologues to extract
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information about stack frames and saved registers.
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For reference here's how prologues look on the mn10200:
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With frame pointer:
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mov fp,a0
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mov sp,fp
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add <size>,sp
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Register saves for d2, d3, a1, a2 as needed. Saves start
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at fp - <size> + <outgoing_args_size> and work towards higher
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addresses. Note that the saves are actually done off the stack
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pointer in the prologue! This makes for smaller code and easier
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prologue scanning as the displacement fields will unlikely
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be more than 8 bits!
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Without frame pointer:
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add <size>,sp
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Register saves for d2, d3, a1, a2 as needed. Saves start
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at sp + <outgoing_args_size> and work towards higher addresses.
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Out of line prologue:
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add <local size>,sp -- optional
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jsr __prologue
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add <outgoing_size>,sp -- optional
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The stack pointer remains constant throughout the life of most
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functions. As a result the compiler will usually omit the
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frame pointer, so we must handle frame pointerless functions. */
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/* Analyze the prologue to determine where registers are saved,
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the end of the prologue, etc etc. Return the end of the prologue
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scanned.
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We store into FI (if non-null) several tidbits of information:
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* stack_size -- size of this stack frame. Note that if we stop in
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certain parts of the prologue/epilogue we may claim the size of the
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current frame is zero. This happens when the current frame has
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not been allocated yet or has already been deallocated.
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* fsr -- Addresses of registers saved in the stack by this frame.
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* status -- A (relatively) generic status indicator. It's a bitmask
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with the following bits:
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MY_FRAME_IN_SP: The base of the current frame is actually in
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the stack pointer. This can happen for frame pointerless
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functions, or cases where we're stopped in the prologue/epilogue
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itself. For these cases mn10200_analyze_prologue will need up
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update fi->frame before returning or analyzing the register
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save instructions.
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MY_FRAME_IN_FP: The base of the current frame is in the
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frame pointer register ($a2).
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CALLER_A2_IN_A0: $a2 from the caller's frame is temporarily
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in $a0. This can happen if we're stopped in the prologue.
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NO_MORE_FRAMES: Set this if the current frame is "start" or
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if the first instruction looks like mov <imm>,sp. This tells
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frame chain to not bother trying to unwind past this frame. */
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/* *INDENT-ON* */
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#define MY_FRAME_IN_SP 0x1
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#define MY_FRAME_IN_FP 0x2
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#define CALLER_A2_IN_A0 0x4
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#define NO_MORE_FRAMES 0x8
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static CORE_ADDR
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mn10200_analyze_prologue (struct frame_info *fi, CORE_ADDR pc)
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{
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CORE_ADDR func_addr, func_end, addr, stop;
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CORE_ADDR stack_size;
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unsigned char buf[4];
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int status;
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char *name;
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int out_of_line_prologue = 0;
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/* Use the PC in the frame if it's provided to look up the
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start of this function. */
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pc = (fi ? fi->pc : pc);
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/* Find the start of this function. */
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status = find_pc_partial_function (pc, &name, &func_addr, &func_end);
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/* Do nothing if we couldn't find the start of this function or if we're
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stopped at the first instruction in the prologue. */
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if (status == 0)
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return pc;
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/* If we're in start, then give up. */
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if (strcmp (name, "start") == 0)
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{
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if (fi)
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fi->status = NO_MORE_FRAMES;
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return pc;
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}
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/* At the start of a function our frame is in the stack pointer. */
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if (fi)
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fi->status = MY_FRAME_IN_SP;
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/* If we're physically on an RTS instruction, then our frame has already
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been deallocated.
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fi->frame is bogus, we need to fix it. */
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if (fi && fi->pc + 1 == func_end)
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{
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status = target_read_memory (fi->pc, buf, 1);
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if (status != 0)
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{
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if (fi->next == NULL)
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fi->frame = read_sp ();
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return fi->pc;
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}
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if (buf[0] == 0xfe)
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{
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if (fi->next == NULL)
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fi->frame = read_sp ();
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return fi->pc;
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}
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}
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/* Similarly if we're stopped on the first insn of a prologue as our
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frame hasn't been allocated yet. */
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if (fi && fi->pc == func_addr)
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{
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if (fi->next == NULL)
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fi->frame = read_sp ();
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return fi->pc;
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}
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/* Figure out where to stop scanning. */
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stop = fi ? fi->pc : func_end;
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/* Don't walk off the end of the function. */
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stop = stop > func_end ? func_end : stop;
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/* Start scanning on the first instruction of this function. */
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addr = func_addr;
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status = target_read_memory (addr, buf, 2);
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if (status != 0)
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{
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if (fi && fi->next == NULL && fi->status & MY_FRAME_IN_SP)
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fi->frame = read_sp ();
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return addr;
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}
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/* First see if this insn sets the stack pointer; if so, it's something
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we won't understand, so quit now. */
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if (buf[0] == 0xdf
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|| (buf[0] == 0xf4 && buf[1] == 0x77))
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{
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if (fi)
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fi->status = NO_MORE_FRAMES;
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return addr;
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}
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/* Now see if we have a frame pointer.
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Search for mov a2,a0 (0xf278)
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then mov a3,a2 (0xf27e). */
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if (buf[0] == 0xf2 && buf[1] == 0x78)
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{
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/* Our caller's $a2 will be found in $a0 now. Note it for
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our callers. */
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if (fi)
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fi->status |= CALLER_A2_IN_A0;
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addr += 2;
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if (addr >= stop)
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{
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/* We still haven't allocated our local stack. Handle this
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as if we stopped on the first or last insn of a function. */
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if (fi && fi->next == NULL)
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fi->frame = read_sp ();
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return addr;
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}
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status = target_read_memory (addr, buf, 2);
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if (status != 0)
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{
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if (fi && fi->next == NULL)
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fi->frame = read_sp ();
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return addr;
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}
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if (buf[0] == 0xf2 && buf[1] == 0x7e)
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{
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addr += 2;
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/* Our frame pointer is valid now. */
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if (fi)
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{
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fi->status |= MY_FRAME_IN_FP;
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fi->status &= ~MY_FRAME_IN_SP;
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}
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if (addr >= stop)
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return addr;
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}
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else
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{
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if (fi && fi->next == NULL)
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fi->frame = read_sp ();
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return addr;
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}
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}
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/* Next we should allocate the local frame.
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Search for add imm8,a3 (0xd3XX)
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or add imm16,a3 (0xf70bXXXX)
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or add imm24,a3 (0xf467XXXXXX).
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If none of the above was found, then this prologue has
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no stack, and therefore can't have any register saves,
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so quit now. */
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status = target_read_memory (addr, buf, 2);
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if (status != 0)
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{
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if (fi && fi->next == NULL && (fi->status & MY_FRAME_IN_SP))
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fi->frame = read_sp ();
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return addr;
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}
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if (buf[0] == 0xd3)
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{
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stack_size = extract_signed_integer (&buf[1], 1);
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if (fi)
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fi->stack_size = stack_size;
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addr += 2;
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if (addr >= stop)
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{
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if (fi && fi->next == NULL && (fi->status & MY_FRAME_IN_SP))
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fi->frame = read_sp () - stack_size;
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return addr;
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}
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}
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else if (buf[0] == 0xf7 && buf[1] == 0x0b)
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{
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status = target_read_memory (addr + 2, buf, 2);
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if (status != 0)
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{
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if (fi && fi->next == NULL && (fi->status & MY_FRAME_IN_SP))
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fi->frame = read_sp ();
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return addr;
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}
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stack_size = extract_signed_integer (buf, 2);
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if (fi)
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fi->stack_size = stack_size;
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addr += 4;
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if (addr >= stop)
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{
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if (fi && fi->next == NULL && (fi->status & MY_FRAME_IN_SP))
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fi->frame = read_sp () - stack_size;
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return addr;
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}
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}
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else if (buf[0] == 0xf4 && buf[1] == 0x67)
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{
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status = target_read_memory (addr + 2, buf, 3);
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if (status != 0)
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{
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if (fi && fi->next == NULL && (fi->status & MY_FRAME_IN_SP))
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fi->frame = read_sp ();
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return addr;
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}
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stack_size = extract_signed_integer (buf, 3);
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if (fi)
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fi->stack_size = stack_size;
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addr += 5;
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if (addr >= stop)
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{
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if (fi && fi->next == NULL && (fi->status & MY_FRAME_IN_SP))
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fi->frame = read_sp () - stack_size;
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return addr;
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}
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}
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/* Now see if we have a call to __prologue for an out of line
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prologue. */
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status = target_read_memory (addr, buf, 2);
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if (status != 0)
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return addr;
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/* First check for 16bit pc-relative call to __prologue. */
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if (buf[0] == 0xfd)
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{
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CORE_ADDR temp;
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status = target_read_memory (addr + 1, buf, 2);
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if (status != 0)
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{
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if (fi && fi->next == NULL && (fi->status & MY_FRAME_IN_SP))
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fi->frame = read_sp ();
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return addr;
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}
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/* Get the PC this instruction will branch to. */
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temp = (extract_signed_integer (buf, 2) + addr + 3) & 0xffffff;
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/* Get the name of the function at the target address. */
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status = find_pc_partial_function (temp, &name, NULL, NULL);
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if (status == 0)
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{
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if (fi && fi->next == NULL && (fi->status & MY_FRAME_IN_SP))
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fi->frame = read_sp ();
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return addr;
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}
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/* Note if it is an out of line prologue. */
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out_of_line_prologue = (strcmp (name, "__prologue") == 0);
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/* This sucks up 3 bytes of instruction space. */
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if (out_of_line_prologue)
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addr += 3;
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if (addr >= stop)
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{
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if (fi && fi->next == NULL)
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{
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fi->stack_size -= 16;
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fi->frame = read_sp () - fi->stack_size;
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}
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return addr;
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}
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}
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/* Now check for the 24bit pc-relative call to __prologue. */
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else if (buf[0] == 0xf4 && buf[1] == 0xe1)
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{
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CORE_ADDR temp;
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status = target_read_memory (addr + 2, buf, 3);
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if (status != 0)
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{
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if (fi && fi->next == NULL && (fi->status & MY_FRAME_IN_SP))
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fi->frame = read_sp ();
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return addr;
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}
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/* Get the PC this instruction will branch to. */
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temp = (extract_signed_integer (buf, 3) + addr + 5) & 0xffffff;
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/* Get the name of the function at the target address. */
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status = find_pc_partial_function (temp, &name, NULL, NULL);
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if (status == 0)
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{
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if (fi && fi->next == NULL && (fi->status & MY_FRAME_IN_SP))
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fi->frame = read_sp ();
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return addr;
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}
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/* Note if it is an out of line prologue. */
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out_of_line_prologue = (strcmp (name, "__prologue") == 0);
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/* This sucks up 5 bytes of instruction space. */
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if (out_of_line_prologue)
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addr += 5;
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if (addr >= stop)
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{
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if (fi && fi->next == NULL && (fi->status & MY_FRAME_IN_SP))
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{
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fi->stack_size -= 16;
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fi->frame = read_sp () - fi->stack_size;
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}
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return addr;
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}
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}
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/* Now actually handle the out of line prologue. */
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if (out_of_line_prologue)
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{
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int outgoing_args_size = 0;
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/* First adjust the stack size for this function. The out of
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line prologue saves 4 registers (16bytes of data). */
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if (fi)
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fi->stack_size -= 16;
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/* Update fi->frame if necessary. */
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if (fi && fi->next == NULL)
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fi->frame = read_sp () - fi->stack_size;
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/* After the out of line prologue, there may be another
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stack adjustment for the outgoing arguments.
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Search for add imm8,a3 (0xd3XX)
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or add imm16,a3 (0xf70bXXXX)
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or add imm24,a3 (0xf467XXXXXX). */
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status = target_read_memory (addr, buf, 2);
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if (status != 0)
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{
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if (fi)
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{
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fi->fsr.regs[2] = fi->frame + fi->stack_size + 4;
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fi->fsr.regs[3] = fi->frame + fi->stack_size + 8;
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fi->fsr.regs[5] = fi->frame + fi->stack_size + 12;
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fi->fsr.regs[6] = fi->frame + fi->stack_size + 16;
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}
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return addr;
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}
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if (buf[0] == 0xd3)
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{
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outgoing_args_size = extract_signed_integer (&buf[1], 1);
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addr += 2;
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}
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else if (buf[0] == 0xf7 && buf[1] == 0x0b)
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{
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status = target_read_memory (addr + 2, buf, 2);
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if (status != 0)
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{
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if (fi)
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{
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fi->fsr.regs[2] = fi->frame + fi->stack_size + 4;
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fi->fsr.regs[3] = fi->frame + fi->stack_size + 8;
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fi->fsr.regs[5] = fi->frame + fi->stack_size + 12;
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fi->fsr.regs[6] = fi->frame + fi->stack_size + 16;
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}
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return addr;
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}
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outgoing_args_size = extract_signed_integer (buf, 2);
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addr += 4;
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}
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else if (buf[0] == 0xf4 && buf[1] == 0x67)
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{
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status = target_read_memory (addr + 2, buf, 3);
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if (status != 0)
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{
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if (fi && fi->next == NULL)
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{
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fi->fsr.regs[2] = fi->frame + fi->stack_size + 4;
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fi->fsr.regs[3] = fi->frame + fi->stack_size + 8;
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fi->fsr.regs[5] = fi->frame + fi->stack_size + 12;
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fi->fsr.regs[6] = fi->frame + fi->stack_size + 16;
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}
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return addr;
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}
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outgoing_args_size = extract_signed_integer (buf, 3);
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addr += 5;
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}
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else
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outgoing_args_size = 0;
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/* Now that we know the size of the outgoing arguments, fix
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fi->frame again if this is the innermost frame. */
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if (fi && fi->next == NULL)
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fi->frame -= outgoing_args_size;
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/* Note the register save information and update the stack
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size for this frame too. */
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if (fi)
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{
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fi->fsr.regs[2] = fi->frame + fi->stack_size + 4;
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fi->fsr.regs[3] = fi->frame + fi->stack_size + 8;
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fi->fsr.regs[5] = fi->frame + fi->stack_size + 12;
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fi->fsr.regs[6] = fi->frame + fi->stack_size + 16;
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fi->stack_size += outgoing_args_size;
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}
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/* There can be no more prologue insns, so return now. */
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return addr;
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}
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/* At this point fi->frame needs to be correct.
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If MY_FRAME_IN_SP is set and we're the innermost frame, then we
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need to fix fi->frame so that backtracing, find_frame_saved_regs,
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etc work correctly. */
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if (fi && fi->next == NULL && (fi->status & MY_FRAME_IN_SP) != 0)
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fi->frame = read_sp () - fi->stack_size;
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/* And last we have the register saves. These are relatively
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simple because they're physically done off the stack pointer,
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|
and thus the number of different instructions we need to
|
|
check is greatly reduced because we know the displacements
|
|
will be small.
|
|
|
|
Search for movx d2,(X,a3) (0xf55eXX)
|
|
then movx d3,(X,a3) (0xf55fXX)
|
|
then mov a1,(X,a3) (0x5dXX) No frame pointer case
|
|
then mov a2,(X,a3) (0x5eXX) No frame pointer case
|
|
or mov a0,(X,a3) (0x5cXX) Frame pointer case. */
|
|
|
|
status = target_read_memory (addr, buf, 2);
|
|
if (status != 0)
|
|
return addr;
|
|
if (buf[0] == 0xf5 && buf[1] == 0x5e)
|
|
{
|
|
if (fi)
|
|
{
|
|
status = target_read_memory (addr + 2, buf, 1);
|
|
if (status != 0)
|
|
return addr;
|
|
fi->fsr.regs[2] = (fi->frame + stack_size
|
|
+ extract_signed_integer (buf, 1));
|
|
}
|
|
addr += 3;
|
|
if (addr >= stop)
|
|
return addr;
|
|
status = target_read_memory (addr, buf, 2);
|
|
if (status != 0)
|
|
return addr;
|
|
}
|
|
if (buf[0] == 0xf5 && buf[1] == 0x5f)
|
|
{
|
|
if (fi)
|
|
{
|
|
status = target_read_memory (addr + 2, buf, 1);
|
|
if (status != 0)
|
|
return addr;
|
|
fi->fsr.regs[3] = (fi->frame + stack_size
|
|
+ extract_signed_integer (buf, 1));
|
|
}
|
|
addr += 3;
|
|
if (addr >= stop)
|
|
return addr;
|
|
status = target_read_memory (addr, buf, 2);
|
|
if (status != 0)
|
|
return addr;
|
|
}
|
|
if (buf[0] == 0x5d)
|
|
{
|
|
if (fi)
|
|
{
|
|
status = target_read_memory (addr + 1, buf, 1);
|
|
if (status != 0)
|
|
return addr;
|
|
fi->fsr.regs[5] = (fi->frame + stack_size
|
|
+ extract_signed_integer (buf, 1));
|
|
}
|
|
addr += 2;
|
|
if (addr >= stop)
|
|
return addr;
|
|
status = target_read_memory (addr, buf, 2);
|
|
if (status != 0)
|
|
return addr;
|
|
}
|
|
if (buf[0] == 0x5e || buf[0] == 0x5c)
|
|
{
|
|
if (fi)
|
|
{
|
|
status = target_read_memory (addr + 1, buf, 1);
|
|
if (status != 0)
|
|
return addr;
|
|
fi->fsr.regs[6] = (fi->frame + stack_size
|
|
+ extract_signed_integer (buf, 1));
|
|
fi->status &= ~CALLER_A2_IN_A0;
|
|
}
|
|
addr += 2;
|
|
if (addr >= stop)
|
|
return addr;
|
|
return addr;
|
|
}
|
|
return addr;
|
|
}
|
|
|
|
/* Function: frame_chain
|
|
Figure out and return the caller's frame pointer given current
|
|
frame_info struct.
|
|
|
|
We don't handle dummy frames yet but we would probably just return the
|
|
stack pointer that was in use at the time the function call was made? */
|
|
|
|
CORE_ADDR
|
|
mn10200_frame_chain (struct frame_info *fi)
|
|
{
|
|
struct frame_info dummy_frame;
|
|
|
|
/* Walk through the prologue to determine the stack size,
|
|
location of saved registers, end of the prologue, etc. */
|
|
if (fi->status == 0)
|
|
mn10200_analyze_prologue (fi, (CORE_ADDR) 0);
|
|
|
|
/* Quit now if mn10200_analyze_prologue set NO_MORE_FRAMES. */
|
|
if (fi->status & NO_MORE_FRAMES)
|
|
return 0;
|
|
|
|
/* Now that we've analyzed our prologue, determine the frame
|
|
pointer for our caller.
|
|
|
|
If our caller has a frame pointer, then we need to
|
|
find the entry value of $a2 to our function.
|
|
|
|
If CALLER_A2_IN_A0, then the chain is in $a0.
|
|
|
|
If fsr.regs[6] is nonzero, then it's at the memory
|
|
location pointed to by fsr.regs[6].
|
|
|
|
Else it's still in $a2.
|
|
|
|
If our caller does not have a frame pointer, then his
|
|
frame base is fi->frame + -caller's stack size + 4. */
|
|
|
|
/* The easiest way to get that info is to analyze our caller's frame.
|
|
|
|
So we set up a dummy frame and call mn10200_analyze_prologue to
|
|
find stuff for us. */
|
|
dummy_frame.pc = FRAME_SAVED_PC (fi);
|
|
dummy_frame.frame = fi->frame;
|
|
memset (dummy_frame.fsr.regs, '\000', sizeof dummy_frame.fsr.regs);
|
|
dummy_frame.status = 0;
|
|
dummy_frame.stack_size = 0;
|
|
mn10200_analyze_prologue (&dummy_frame);
|
|
|
|
if (dummy_frame.status & MY_FRAME_IN_FP)
|
|
{
|
|
/* Our caller has a frame pointer. So find the frame in $a2, $a0,
|
|
or in the stack. */
|
|
if (fi->fsr.regs[6])
|
|
return (read_memory_integer (fi->fsr.regs[FP_REGNUM], REGISTER_SIZE)
|
|
& 0xffffff);
|
|
else if (fi->status & CALLER_A2_IN_A0)
|
|
return read_register (4);
|
|
else
|
|
return read_register (FP_REGNUM);
|
|
}
|
|
else
|
|
{
|
|
/* Our caller does not have a frame pointer. So his frame starts
|
|
at the base of our frame (fi->frame) + <his size> + 4 (saved pc). */
|
|
return fi->frame + -dummy_frame.stack_size + 4;
|
|
}
|
|
}
|
|
|
|
/* Function: skip_prologue
|
|
Return the address of the first inst past the prologue of the function. */
|
|
|
|
CORE_ADDR
|
|
mn10200_skip_prologue (CORE_ADDR pc)
|
|
{
|
|
/* We used to check the debug symbols, but that can lose if
|
|
we have a null prologue. */
|
|
return mn10200_analyze_prologue (NULL, pc);
|
|
}
|
|
|
|
/* Function: pop_frame
|
|
This routine gets called when either the user uses the `return'
|
|
command, or the call dummy breakpoint gets hit. */
|
|
|
|
void
|
|
mn10200_pop_frame (struct frame_info *frame)
|
|
{
|
|
int regnum;
|
|
|
|
if (PC_IN_CALL_DUMMY (frame->pc, frame->frame, frame->frame))
|
|
generic_pop_dummy_frame ();
|
|
else
|
|
{
|
|
write_register (PC_REGNUM, FRAME_SAVED_PC (frame));
|
|
|
|
/* Restore any saved registers. */
|
|
for (regnum = 0; regnum < NUM_REGS; regnum++)
|
|
if (frame->fsr.regs[regnum] != 0)
|
|
{
|
|
ULONGEST value;
|
|
|
|
value = read_memory_unsigned_integer (frame->fsr.regs[regnum],
|
|
REGISTER_RAW_SIZE (regnum));
|
|
write_register (regnum, value);
|
|
}
|
|
|
|
/* Actually cut back the stack. */
|
|
write_register (SP_REGNUM, FRAME_FP (frame));
|
|
|
|
/* Don't we need to set the PC?!? XXX FIXME. */
|
|
}
|
|
|
|
/* Throw away any cached frame information. */
|
|
flush_cached_frames ();
|
|
}
|
|
|
|
/* Function: push_arguments
|
|
Setup arguments for a call to the target. Arguments go in
|
|
order on the stack. */
|
|
|
|
CORE_ADDR
|
|
mn10200_push_arguments (int nargs, value_ptr *args, CORE_ADDR sp,
|
|
unsigned char struct_return, CORE_ADDR struct_addr)
|
|
{
|
|
int argnum = 0;
|
|
int len = 0;
|
|
int stack_offset = 0;
|
|
int regsused = struct_return ? 1 : 0;
|
|
|
|
/* This should be a nop, but align the stack just in case something
|
|
went wrong. Stacks are two byte aligned on the mn10200. */
|
|
sp &= ~1;
|
|
|
|
/* Now make space on the stack for the args.
|
|
|
|
XXX This doesn't appear to handle pass-by-invisible reference
|
|
arguments. */
|
|
for (argnum = 0; argnum < nargs; argnum++)
|
|
{
|
|
int arg_length = (TYPE_LENGTH (VALUE_TYPE (args[argnum])) + 1) & ~1;
|
|
|
|
/* If we've used all argument registers, then this argument is
|
|
pushed. */
|
|
if (regsused >= 2 || arg_length > 4)
|
|
{
|
|
regsused = 2;
|
|
len += arg_length;
|
|
}
|
|
/* We know we've got some arg register space left. If this argument
|
|
will fit entirely in regs, then put it there. */
|
|
else if (arg_length <= 2
|
|
|| TYPE_CODE (VALUE_TYPE (args[argnum])) == TYPE_CODE_PTR)
|
|
{
|
|
regsused++;
|
|
}
|
|
else if (regsused == 0)
|
|
{
|
|
regsused = 2;
|
|
}
|
|
else
|
|
{
|
|
regsused = 2;
|
|
len += arg_length;
|
|
}
|
|
}
|
|
|
|
/* Allocate stack space. */
|
|
sp -= len;
|
|
|
|
regsused = struct_return ? 1 : 0;
|
|
/* Push all arguments onto the stack. */
|
|
for (argnum = 0; argnum < nargs; argnum++)
|
|
{
|
|
int len;
|
|
char *val;
|
|
|
|
/* XXX Check this. What about UNIONS? */
|
|
if (TYPE_CODE (VALUE_TYPE (*args)) == TYPE_CODE_STRUCT
|
|
&& TYPE_LENGTH (VALUE_TYPE (*args)) > 8)
|
|
{
|
|
/* XXX Wrong, we want a pointer to this argument. */
|
|
len = TYPE_LENGTH (VALUE_TYPE (*args));
|
|
val = (char *) VALUE_CONTENTS (*args);
|
|
}
|
|
else
|
|
{
|
|
len = TYPE_LENGTH (VALUE_TYPE (*args));
|
|
val = (char *) VALUE_CONTENTS (*args);
|
|
}
|
|
|
|
if (regsused < 2
|
|
&& (len <= 2
|
|
|| TYPE_CODE (VALUE_TYPE (*args)) == TYPE_CODE_PTR))
|
|
{
|
|
write_register (regsused, extract_unsigned_integer (val, 4));
|
|
regsused++;
|
|
}
|
|
else if (regsused == 0 && len == 4)
|
|
{
|
|
write_register (regsused, extract_unsigned_integer (val, 2));
|
|
write_register (regsused + 1, extract_unsigned_integer (val + 2, 2));
|
|
regsused = 2;
|
|
}
|
|
else
|
|
{
|
|
regsused = 2;
|
|
while (len > 0)
|
|
{
|
|
write_memory (sp + stack_offset, val, 2);
|
|
|
|
len -= 2;
|
|
val += 2;
|
|
stack_offset += 2;
|
|
}
|
|
}
|
|
args++;
|
|
}
|
|
|
|
return sp;
|
|
}
|
|
|
|
/* Function: push_return_address (pc)
|
|
Set up the return address for the inferior function call.
|
|
Needed for targets where we don't actually execute a JSR/BSR instruction */
|
|
|
|
CORE_ADDR
|
|
mn10200_push_return_address (CORE_ADDR pc, CORE_ADDR sp)
|
|
{
|
|
unsigned char buf[4];
|
|
|
|
store_unsigned_integer (buf, 4, CALL_DUMMY_ADDRESS ());
|
|
write_memory (sp - 4, buf, 4);
|
|
return sp - 4;
|
|
}
|
|
|
|
/* Function: store_struct_return (addr,sp)
|
|
Store the structure value return address for an inferior function
|
|
call. */
|
|
|
|
CORE_ADDR
|
|
mn10200_store_struct_return (CORE_ADDR addr, CORE_ADDR sp)
|
|
{
|
|
/* The structure return address is passed as the first argument. */
|
|
write_register (0, addr);
|
|
return sp;
|
|
}
|
|
|
|
/* Function: frame_saved_pc
|
|
Find the caller of this frame. We do this by seeing if RP_REGNUM
|
|
is saved in the stack anywhere, otherwise we get it from the
|
|
registers. If the inner frame is a dummy frame, return its PC
|
|
instead of RP, because that's where "caller" of the dummy-frame
|
|
will be found. */
|
|
|
|
CORE_ADDR
|
|
mn10200_frame_saved_pc (struct frame_info *fi)
|
|
{
|
|
/* The saved PC will always be at the base of the current frame. */
|
|
return (read_memory_integer (fi->frame, REGISTER_SIZE) & 0xffffff);
|
|
}
|
|
|
|
/* Function: init_extra_frame_info
|
|
Setup the frame's frame pointer, pc, and frame addresses for saved
|
|
registers. Most of the work is done in mn10200_analyze_prologue().
|
|
|
|
Note that when we are called for the last frame (currently active frame),
|
|
that fi->pc and fi->frame will already be setup. However, fi->frame will
|
|
be valid only if this routine uses FP. For previous frames, fi-frame will
|
|
always be correct. mn10200_analyze_prologue will fix fi->frame if
|
|
it's not valid.
|
|
|
|
We can be called with the PC in the call dummy under two circumstances.
|
|
First, during normal backtracing, second, while figuring out the frame
|
|
pointer just prior to calling the target function (see run_stack_dummy). */
|
|
|
|
void
|
|
mn10200_init_extra_frame_info (struct frame_info *fi)
|
|
{
|
|
if (fi->next)
|
|
fi->pc = FRAME_SAVED_PC (fi->next);
|
|
|
|
memset (fi->fsr.regs, '\000', sizeof fi->fsr.regs);
|
|
fi->status = 0;
|
|
fi->stack_size = 0;
|
|
|
|
mn10200_analyze_prologue (fi, 0);
|
|
}
|
|
|
|
void
|
|
_initialize_mn10200_tdep (void)
|
|
{
|
|
tm_print_insn = print_insn_mn10200;
|
|
}
|