43 lines
1.6 KiB
C
43 lines
1.6 KiB
C
/* Target-dependent code for Intel 386 running LynxOS.
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Copyright 1993 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., 675 Mass Ave, Cambridge, MA 02139, USA. */
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#include "defs.h"
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#include "inferior.h"
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#include "target.h"
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/* Return the PC of the caller from the call frame. Assumes the subr prologue
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has already been executed, and the frame pointer setup. If this is the
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outermost frame, we check to see if we are in a system call by examining the
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previous instruction. If so, then the return PC is actually at SP+4 because
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system calls use a different calling sequence. */
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CORE_ADDR
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i386lynx_saved_pc_after_call (frame)
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struct frame_info *frame;
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{
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char opcode[7];
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static const unsigned char call_inst[] = {0x9a, 0, 0, 0, 0, 8, 0}; /* lcall 0x8,0x0 */
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read_memory (frame->pc - 7, opcode, 7);
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if (memcmp (opcode, call_inst, 7) == 0)
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return read_memory_integer (read_register (SP_REGNUM) + 4, 4);
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return read_memory_integer (read_register (SP_REGNUM), 4);
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}
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