2111 lines
59 KiB
C
2111 lines
59 KiB
C
/* Machine-dependent code which would otherwise be in inflow.c and core.c,
|
||
for GDB, the GNU debugger. This code is for the HP PA-RISC cpu.
|
||
Copyright 1986, 1987, 1989, 1990, 1991, 1992, 1993 Free Software Foundation, Inc.
|
||
|
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Contributed by the Center for Software Science at the
|
||
University of Utah (pa-gdb-bugs@cs.utah.edu).
|
||
|
||
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.
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||
|
||
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.
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||
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||
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., 675 Mass Ave, Cambridge, MA 02139, USA. */
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||
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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 "value.h"
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/* For argument passing to the inferior */
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#include "symtab.h"
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#ifdef USG
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#include <sys/types.h>
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#endif
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#include <sys/param.h>
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#include <sys/dir.h>
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#include <signal.h>
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#include <sys/ioctl.h>
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#ifdef COFF_ENCAPSULATE
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#include "a.out.encap.h"
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#else
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#include <a.out.h>
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#endif
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#ifndef N_SET_MAGIC
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#define N_SET_MAGIC(exec, val) ((exec).a_magic = (val))
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#endif
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/*#include <sys/user.h> After a.out.h */
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#include <sys/file.h>
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#include <sys/stat.h>
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#include <machine/psl.h>
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#include "wait.h"
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#include "gdbcore.h"
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#include "gdbcmd.h"
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#include "target.h"
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||
#include "symfile.h"
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#include "objfiles.h"
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||
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static int restore_pc_queue PARAMS ((struct frame_saved_regs *fsr));
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static int hppa_alignof PARAMS ((struct type *arg));
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CORE_ADDR frame_saved_pc PARAMS ((FRAME frame));
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static int prologue_inst_adjust_sp PARAMS ((unsigned long));
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static int is_branch PARAMS ((unsigned long));
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static int inst_saves_gr PARAMS ((unsigned long));
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static int inst_saves_fr PARAMS ((unsigned long));
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static int pc_in_interrupt_handler PARAMS ((CORE_ADDR));
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static int pc_in_linker_stub PARAMS ((CORE_ADDR));
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static int compare_unwind_entries PARAMS ((struct unwind_table_entry *,
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struct unwind_table_entry *));
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static void read_unwind_info PARAMS ((struct objfile *));
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static void internalize_unwinds PARAMS ((struct objfile *,
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struct unwind_table_entry *,
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asection *, unsigned int,
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unsigned int));
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/* Routines to extract various sized constants out of hppa
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instructions. */
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/* This assumes that no garbage lies outside of the lower bits of
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value. */
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int
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sign_extend (val, bits)
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unsigned val, bits;
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{
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return (int)(val >> bits - 1 ? (-1 << bits) | val : val);
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}
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/* For many immediate values the sign bit is the low bit! */
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int
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low_sign_extend (val, bits)
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unsigned val, bits;
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{
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return (int)((val & 0x1 ? (-1 << (bits - 1)) : 0) | val >> 1);
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}
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/* extract the immediate field from a ld{bhw}s instruction */
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unsigned
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get_field (val, from, to)
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unsigned val, from, to;
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{
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val = val >> 31 - to;
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return val & ((1 << 32 - from) - 1);
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}
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unsigned
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set_field (val, from, to, new_val)
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unsigned *val, from, to;
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{
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unsigned mask = ~((1 << (to - from + 1)) << (31 - from));
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return *val = *val & mask | (new_val << (31 - from));
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}
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||
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/* extract a 3-bit space register number from a be, ble, mtsp or mfsp */
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extract_3 (word)
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unsigned word;
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{
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return GET_FIELD (word, 18, 18) << 2 | GET_FIELD (word, 16, 17);
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||
}
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||
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extract_5_load (word)
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unsigned word;
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{
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return low_sign_extend (word >> 16 & MASK_5, 5);
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}
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/* extract the immediate field from a st{bhw}s instruction */
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int
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||
extract_5_store (word)
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unsigned word;
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||
{
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||
return low_sign_extend (word & MASK_5, 5);
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||
}
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||
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||
/* extract the immediate field from a break instruction */
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||
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||
unsigned
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||
extract_5r_store (word)
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||
unsigned word;
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||
{
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||
return (word & MASK_5);
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||
}
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||
|
||
/* extract the immediate field from a {sr}sm instruction */
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||
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unsigned
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extract_5R_store (word)
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||
unsigned word;
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||
{
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||
return (word >> 16 & MASK_5);
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}
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||
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||
/* extract an 11 bit immediate field */
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||
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int
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extract_11 (word)
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unsigned word;
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{
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return low_sign_extend (word & MASK_11, 11);
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}
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||
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/* extract a 14 bit immediate field */
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||
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int
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||
extract_14 (word)
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||
unsigned word;
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||
{
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||
return low_sign_extend (word & MASK_14, 14);
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||
}
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/* deposit a 14 bit constant in a word */
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||
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unsigned
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deposit_14 (opnd, word)
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int opnd;
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unsigned word;
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{
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unsigned sign = (opnd < 0 ? 1 : 0);
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return word | ((unsigned)opnd << 1 & MASK_14) | sign;
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}
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||
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/* extract a 21 bit constant */
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int
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extract_21 (word)
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unsigned word;
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{
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int val;
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word &= MASK_21;
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word <<= 11;
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val = GET_FIELD (word, 20, 20);
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val <<= 11;
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val |= GET_FIELD (word, 9, 19);
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val <<= 2;
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val |= GET_FIELD (word, 5, 6);
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val <<= 5;
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val |= GET_FIELD (word, 0, 4);
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val <<= 2;
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val |= GET_FIELD (word, 7, 8);
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return sign_extend (val, 21) << 11;
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}
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/* deposit a 21 bit constant in a word. Although 21 bit constants are
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usually the top 21 bits of a 32 bit constant, we assume that only
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the low 21 bits of opnd are relevant */
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||
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unsigned
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deposit_21 (opnd, word)
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unsigned opnd, word;
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{
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unsigned val = 0;
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val |= GET_FIELD (opnd, 11 + 14, 11 + 18);
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val <<= 2;
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val |= GET_FIELD (opnd, 11 + 12, 11 + 13);
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val <<= 2;
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val |= GET_FIELD (opnd, 11 + 19, 11 + 20);
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val <<= 11;
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val |= GET_FIELD (opnd, 11 + 1, 11 + 11);
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val <<= 1;
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val |= GET_FIELD (opnd, 11 + 0, 11 + 0);
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return word | val;
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}
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||
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/* extract a 12 bit constant from branch instructions */
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int
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extract_12 (word)
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unsigned word;
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{
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return sign_extend (GET_FIELD (word, 19, 28) |
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GET_FIELD (word, 29, 29) << 10 |
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(word & 0x1) << 11, 12) << 2;
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}
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/* extract a 17 bit constant from branch instructions, returning the
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19 bit signed value. */
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int
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extract_17 (word)
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unsigned word;
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{
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return sign_extend (GET_FIELD (word, 19, 28) |
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GET_FIELD (word, 29, 29) << 10 |
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GET_FIELD (word, 11, 15) << 11 |
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(word & 0x1) << 16, 17) << 2;
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}
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/* Compare the start address for two unwind entries returning 1 if
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the first address is larger than the second, -1 if the second is
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larger than the first, and zero if they are equal. */
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static int
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compare_unwind_entries (a, b)
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struct unwind_table_entry *a;
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struct unwind_table_entry *b;
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{
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if (a->region_start > b->region_start)
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return 1;
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else if (a->region_start < b->region_start)
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return -1;
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else
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return 0;
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}
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static void
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internalize_unwinds (objfile, table, section, entries, size)
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struct objfile *objfile;
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struct unwind_table_entry *table;
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asection *section;
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unsigned int entries, size;
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{
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||
/* We will read the unwind entries into temporary memory, then
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fill in the actual unwind table. */
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if (size > 0)
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{
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unsigned long tmp;
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unsigned i;
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char *buf = alloca (size);
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bfd_get_section_contents (objfile->obfd, section, buf, 0, size);
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/* Now internalize the information being careful to handle host/target
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endian issues. */
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for (i = 0; i < entries; i++)
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{
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table[i].region_start = bfd_get_32 (objfile->obfd,
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(bfd_byte *)buf);
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buf += 4;
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table[i].region_end = bfd_get_32 (objfile->obfd, (bfd_byte *)buf);
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buf += 4;
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tmp = bfd_get_32 (objfile->obfd, (bfd_byte *)buf);
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buf += 4;
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table[i].Cannot_unwind = (tmp >> 31) & 0x1;;
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table[i].Millicode = (tmp >> 30) & 0x1;
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table[i].Millicode_save_sr0 = (tmp >> 29) & 0x1;
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table[i].Region_description = (tmp >> 27) & 0x3;
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table[i].reserved1 = (tmp >> 26) & 0x1;
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table[i].Entry_SR = (tmp >> 25) & 0x1;
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table[i].Entry_FR = (tmp >> 21) & 0xf;
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table[i].Entry_GR = (tmp >> 16) & 0x1f;
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table[i].Args_stored = (tmp >> 15) & 0x1;
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table[i].Variable_Frame = (tmp >> 14) & 0x1;
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table[i].Separate_Package_Body = (tmp >> 13) & 0x1;
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table[i].Frame_Extension_Millicode = (tmp >> 12 ) & 0x1;
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table[i].Stack_Overflow_Check = (tmp >> 11) & 0x1;
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table[i].Two_Instruction_SP_Increment = (tmp >> 10) & 0x1;
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table[i].Ada_Region = (tmp >> 9) & 0x1;
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table[i].reserved2 = (tmp >> 5) & 0xf;
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table[i].Save_SP = (tmp >> 4) & 0x1;
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table[i].Save_RP = (tmp >> 3) & 0x1;
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table[i].Save_MRP_in_frame = (tmp >> 2) & 0x1;
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table[i].extn_ptr_defined = (tmp >> 1) & 0x1;
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table[i].Cleanup_defined = tmp & 0x1;
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tmp = bfd_get_32 (objfile->obfd, (bfd_byte *)buf);
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buf += 4;
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table[i].MPE_XL_interrupt_marker = (tmp >> 31) & 0x1;
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table[i].HP_UX_interrupt_marker = (tmp >> 30) & 0x1;
|
||
table[i].Large_frame = (tmp >> 29) & 0x1;
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||
table[i].reserved4 = (tmp >> 27) & 0x3;
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table[i].Total_frame_size = tmp & 0x7ffffff;
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||
}
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||
}
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}
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||
|
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/* Read in the backtrace information stored in the `$UNWIND_START$' section of
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the object file. This info is used mainly by find_unwind_entry() to find
|
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out the stack frame size and frame pointer used by procedures. We put
|
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everything on the psymbol obstack in the objfile so that it automatically
|
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gets freed when the objfile is destroyed. */
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||
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static void
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||
read_unwind_info (objfile)
|
||
struct objfile *objfile;
|
||
{
|
||
asection *unwind_sec, *elf_unwind_sec, *stub_unwind_sec;
|
||
unsigned unwind_size, elf_unwind_size, stub_unwind_size, total_size;
|
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unsigned index, unwind_entries, elf_unwind_entries;
|
||
unsigned stub_entries, total_entries;
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struct obj_unwind_info *ui;
|
||
|
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ui = obstack_alloc (&objfile->psymbol_obstack,
|
||
sizeof (struct obj_unwind_info));
|
||
|
||
ui->table = NULL;
|
||
ui->cache = NULL;
|
||
ui->last = -1;
|
||
|
||
/* Get hooks to all unwind sections. Note there is no linker-stub unwind
|
||
section in ELF at the moment. */
|
||
unwind_sec = bfd_get_section_by_name (objfile->obfd, "$UNWIND_START$");
|
||
elf_unwind_sec = bfd_get_section_by_name (objfile->obfd, ".hppa_unwind");
|
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stub_unwind_sec = bfd_get_section_by_name (objfile->obfd, "$UNWIND_END$");
|
||
|
||
/* Get sizes and unwind counts for all sections. */
|
||
if (unwind_sec)
|
||
{
|
||
unwind_size = bfd_section_size (objfile->obfd, unwind_sec);
|
||
unwind_entries = unwind_size / UNWIND_ENTRY_SIZE;
|
||
}
|
||
else
|
||
{
|
||
unwind_size = 0;
|
||
unwind_entries = 0;
|
||
}
|
||
|
||
if (elf_unwind_sec)
|
||
{
|
||
elf_unwind_size = bfd_section_size (objfile->obfd, elf_unwind_sec);
|
||
elf_unwind_entries = elf_unwind_size / UNWIND_ENTRY_SIZE;
|
||
}
|
||
|
||
if (stub_unwind_sec)
|
||
{
|
||
stub_unwind_size = bfd_section_size (objfile->obfd, stub_unwind_sec);
|
||
stub_entries = stub_unwind_size / STUB_UNWIND_ENTRY_SIZE;
|
||
}
|
||
else
|
||
{
|
||
stub_unwind_size = 0;
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||
stub_entries = 0;
|
||
}
|
||
|
||
/* Compute total number of unwind entries and their total size. */
|
||
total_entries = unwind_entries + elf_unwind_entries + stub_entries;
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||
total_size = total_entries * sizeof (struct unwind_table_entry);
|
||
|
||
/* Allocate memory for the unwind table. */
|
||
ui->table = obstack_alloc (&objfile->psymbol_obstack, total_size);
|
||
ui->last = total_entries - 1;
|
||
|
||
/* Internalize the standard unwind entries. */
|
||
index = 0;
|
||
internalize_unwinds (objfile, &ui->table[index], unwind_sec,
|
||
unwind_entries, unwind_size);
|
||
index += unwind_entries;
|
||
internalize_unwinds (objfile, &ui->table[index], elf_unwind_sec,
|
||
elf_unwind_entries, elf_unwind_size);
|
||
index += elf_unwind_entries;
|
||
|
||
/* Now internalize the stub unwind entries. */
|
||
if (stub_unwind_size > 0)
|
||
{
|
||
unsigned int i;
|
||
char *buf = alloca (stub_unwind_size);
|
||
|
||
/* Read in the stub unwind entries. */
|
||
bfd_get_section_contents (objfile->obfd, stub_unwind_sec, buf,
|
||
0, stub_unwind_size);
|
||
|
||
/* Now convert them into regular unwind entries. */
|
||
for (i = 0; i < stub_entries; i++, index++)
|
||
{
|
||
/* Clear out the next unwind entry. */
|
||
memset (&ui->table[index], 0, sizeof (struct unwind_table_entry));
|
||
|
||
/* Convert offset & size into region_start and region_end.
|
||
Stuff away the stub type into "reserved" fields. */
|
||
ui->table[index].region_start = bfd_get_32 (objfile->obfd,
|
||
(bfd_byte *) buf);
|
||
buf += 4;
|
||
ui->table[index].stub_type = bfd_get_8 (objfile->obfd,
|
||
(bfd_byte *) buf);
|
||
buf += 2;
|
||
ui->table[index].region_end
|
||
= ui->table[index].region_start + 4 *
|
||
(bfd_get_16 (objfile->obfd, (bfd_byte *) buf) - 1);
|
||
buf += 2;
|
||
}
|
||
|
||
}
|
||
|
||
/* Unwind table needs to be kept sorted. */
|
||
qsort (ui->table, total_entries, sizeof (struct unwind_table_entry),
|
||
compare_unwind_entries);
|
||
|
||
/* Keep a pointer to the unwind information. */
|
||
objfile->obj_private = (PTR) ui;
|
||
}
|
||
|
||
/* Lookup the unwind (stack backtrace) info for the given PC. We search all
|
||
of the objfiles seeking the unwind table entry for this PC. Each objfile
|
||
contains a sorted list of struct unwind_table_entry. Since we do a binary
|
||
search of the unwind tables, we depend upon them to be sorted. */
|
||
|
||
static struct unwind_table_entry *
|
||
find_unwind_entry(pc)
|
||
CORE_ADDR pc;
|
||
{
|
||
int first, middle, last;
|
||
struct objfile *objfile;
|
||
|
||
ALL_OBJFILES (objfile)
|
||
{
|
||
struct obj_unwind_info *ui;
|
||
|
||
ui = OBJ_UNWIND_INFO (objfile);
|
||
|
||
if (!ui)
|
||
{
|
||
read_unwind_info (objfile);
|
||
ui = OBJ_UNWIND_INFO (objfile);
|
||
}
|
||
|
||
/* First, check the cache */
|
||
|
||
if (ui->cache
|
||
&& pc >= ui->cache->region_start
|
||
&& pc <= ui->cache->region_end)
|
||
return ui->cache;
|
||
|
||
/* Not in the cache, do a binary search */
|
||
|
||
first = 0;
|
||
last = ui->last;
|
||
|
||
while (first <= last)
|
||
{
|
||
middle = (first + last) / 2;
|
||
if (pc >= ui->table[middle].region_start
|
||
&& pc <= ui->table[middle].region_end)
|
||
{
|
||
ui->cache = &ui->table[middle];
|
||
return &ui->table[middle];
|
||
}
|
||
|
||
if (pc < ui->table[middle].region_start)
|
||
last = middle - 1;
|
||
else
|
||
first = middle + 1;
|
||
}
|
||
} /* ALL_OBJFILES() */
|
||
return NULL;
|
||
}
|
||
|
||
/* Called to determine if PC is in an interrupt handler of some
|
||
kind. */
|
||
|
||
static int
|
||
pc_in_interrupt_handler (pc)
|
||
CORE_ADDR pc;
|
||
{
|
||
struct unwind_table_entry *u;
|
||
struct minimal_symbol *msym_us;
|
||
|
||
u = find_unwind_entry (pc);
|
||
if (!u)
|
||
return 0;
|
||
|
||
/* Oh joys. HPUX sets the interrupt bit for _sigreturn even though
|
||
its frame isn't a pure interrupt frame. Deal with this. */
|
||
msym_us = lookup_minimal_symbol_by_pc (pc);
|
||
|
||
return u->HP_UX_interrupt_marker && !IN_SIGTRAMP (pc, SYMBOL_NAME (msym_us));
|
||
}
|
||
|
||
/* Called when no unwind descriptor was found for PC. Returns 1 if it
|
||
appears that PC is in a linker stub. */
|
||
|
||
static int
|
||
pc_in_linker_stub (pc)
|
||
CORE_ADDR pc;
|
||
{
|
||
int found_magic_instruction = 0;
|
||
int i;
|
||
char buf[4];
|
||
|
||
/* If unable to read memory, assume pc is not in a linker stub. */
|
||
if (target_read_memory (pc, buf, 4) != 0)
|
||
return 0;
|
||
|
||
/* We are looking for something like
|
||
|
||
; $$dyncall jams RP into this special spot in the frame (RP')
|
||
; before calling the "call stub"
|
||
ldw -18(sp),rp
|
||
|
||
ldsid (rp),r1 ; Get space associated with RP into r1
|
||
mtsp r1,sp ; Move it into space register 0
|
||
be,n 0(sr0),rp) ; back to your regularly scheduled program
|
||
*/
|
||
|
||
/* Maximum known linker stub size is 4 instructions. Search forward
|
||
from the given PC, then backward. */
|
||
for (i = 0; i < 4; i++)
|
||
{
|
||
/* If we hit something with an unwind, stop searching this direction. */
|
||
|
||
if (find_unwind_entry (pc + i * 4) != 0)
|
||
break;
|
||
|
||
/* Check for ldsid (rp),r1 which is the magic instruction for a
|
||
return from a cross-space function call. */
|
||
if (read_memory_integer (pc + i * 4, 4) == 0x004010a1)
|
||
{
|
||
found_magic_instruction = 1;
|
||
break;
|
||
}
|
||
/* Add code to handle long call/branch and argument relocation stubs
|
||
here. */
|
||
}
|
||
|
||
if (found_magic_instruction != 0)
|
||
return 1;
|
||
|
||
/* Now look backward. */
|
||
for (i = 0; i < 4; i++)
|
||
{
|
||
/* If we hit something with an unwind, stop searching this direction. */
|
||
|
||
if (find_unwind_entry (pc - i * 4) != 0)
|
||
break;
|
||
|
||
/* Check for ldsid (rp),r1 which is the magic instruction for a
|
||
return from a cross-space function call. */
|
||
if (read_memory_integer (pc - i * 4, 4) == 0x004010a1)
|
||
{
|
||
found_magic_instruction = 1;
|
||
break;
|
||
}
|
||
/* Add code to handle long call/branch and argument relocation stubs
|
||
here. */
|
||
}
|
||
return found_magic_instruction;
|
||
}
|
||
|
||
static int
|
||
find_return_regnum(pc)
|
||
CORE_ADDR pc;
|
||
{
|
||
struct unwind_table_entry *u;
|
||
|
||
u = find_unwind_entry (pc);
|
||
|
||
if (!u)
|
||
return RP_REGNUM;
|
||
|
||
if (u->Millicode)
|
||
return 31;
|
||
|
||
return RP_REGNUM;
|
||
}
|
||
|
||
/* Return size of frame, or -1 if we should use a frame pointer. */
|
||
int
|
||
find_proc_framesize (pc)
|
||
CORE_ADDR pc;
|
||
{
|
||
struct unwind_table_entry *u;
|
||
struct minimal_symbol *msym_us;
|
||
|
||
u = find_unwind_entry (pc);
|
||
|
||
if (!u)
|
||
{
|
||
if (pc_in_linker_stub (pc))
|
||
/* Linker stubs have a zero size frame. */
|
||
return 0;
|
||
else
|
||
return -1;
|
||
}
|
||
|
||
msym_us = lookup_minimal_symbol_by_pc (pc);
|
||
|
||
/* If Save_SP is set, and we're not in an interrupt or signal caller,
|
||
then we have a frame pointer. Use it. */
|
||
if (u->Save_SP && !pc_in_interrupt_handler (pc)
|
||
&& !IN_SIGTRAMP (pc, SYMBOL_NAME (msym_us)))
|
||
return -1;
|
||
|
||
return u->Total_frame_size << 3;
|
||
}
|
||
|
||
/* Return offset from sp at which rp is saved, or 0 if not saved. */
|
||
static int rp_saved PARAMS ((CORE_ADDR));
|
||
|
||
static int
|
||
rp_saved (pc)
|
||
CORE_ADDR pc;
|
||
{
|
||
struct unwind_table_entry *u;
|
||
|
||
u = find_unwind_entry (pc);
|
||
|
||
if (!u)
|
||
{
|
||
if (pc_in_linker_stub (pc))
|
||
/* This is the so-called RP'. */
|
||
return -24;
|
||
else
|
||
return 0;
|
||
}
|
||
|
||
if (u->Save_RP)
|
||
return -20;
|
||
else if (u->stub_type != 0)
|
||
{
|
||
switch (u->stub_type)
|
||
{
|
||
case EXPORT:
|
||
return -24;
|
||
case PARAMETER_RELOCATION:
|
||
return -8;
|
||
default:
|
||
return 0;
|
||
}
|
||
}
|
||
else
|
||
return 0;
|
||
}
|
||
|
||
int
|
||
frameless_function_invocation (frame)
|
||
FRAME frame;
|
||
{
|
||
struct unwind_table_entry *u;
|
||
|
||
u = find_unwind_entry (frame->pc);
|
||
|
||
if (u == 0)
|
||
return 0;
|
||
|
||
return (u->Total_frame_size == 0 && u->stub_type == 0);
|
||
}
|
||
|
||
CORE_ADDR
|
||
saved_pc_after_call (frame)
|
||
FRAME frame;
|
||
{
|
||
int ret_regnum;
|
||
|
||
ret_regnum = find_return_regnum (get_frame_pc (frame));
|
||
|
||
return read_register (ret_regnum) & ~0x3;
|
||
}
|
||
|
||
CORE_ADDR
|
||
frame_saved_pc (frame)
|
||
FRAME frame;
|
||
{
|
||
CORE_ADDR pc = get_frame_pc (frame);
|
||
struct unwind_table_entry *u;
|
||
|
||
/* BSD, HPUX & OSF1 all lay out the hardware state in the same manner
|
||
at the base of the frame in an interrupt handler. Registers within
|
||
are saved in the exact same order as GDB numbers registers. How
|
||
convienent. */
|
||
if (pc_in_interrupt_handler (pc))
|
||
return read_memory_integer (frame->frame + PC_REGNUM * 4, 4) & ~0x3;
|
||
|
||
/* Deal with signal handler caller frames too. */
|
||
if (frame->signal_handler_caller)
|
||
{
|
||
CORE_ADDR rp;
|
||
FRAME_SAVED_PC_IN_SIGTRAMP (frame, &rp);
|
||
return rp;
|
||
}
|
||
|
||
restart:
|
||
if (frameless_function_invocation (frame))
|
||
{
|
||
int ret_regnum;
|
||
|
||
ret_regnum = find_return_regnum (pc);
|
||
|
||
/* If the next frame is an interrupt frame or a signal
|
||
handler caller, then we need to look in the saved
|
||
register area to get the return pointer (the values
|
||
in the registers may not correspond to anything useful). */
|
||
if (frame->next
|
||
&& (frame->next->signal_handler_caller
|
||
|| pc_in_interrupt_handler (frame->next->pc)))
|
||
{
|
||
struct frame_info *fi;
|
||
struct frame_saved_regs saved_regs;
|
||
|
||
fi = get_frame_info (frame->next);
|
||
get_frame_saved_regs (fi, &saved_regs);
|
||
if (read_memory_integer (saved_regs.regs[FLAGS_REGNUM] & 0x2, 4))
|
||
pc = read_memory_integer (saved_regs.regs[31], 4) & ~0x3;
|
||
else
|
||
pc = read_memory_integer (saved_regs.regs[RP_REGNUM], 4) & ~0x3;
|
||
}
|
||
else
|
||
pc = read_register (ret_regnum) & ~0x3;
|
||
}
|
||
else
|
||
{
|
||
int rp_offset = rp_saved (pc);
|
||
|
||
/* Similar to code in frameless function case. If the next
|
||
frame is a signal or interrupt handler, then dig the right
|
||
information out of the saved register info. */
|
||
if (rp_offset == 0
|
||
&& frame->next
|
||
&& (frame->next->signal_handler_caller
|
||
|| pc_in_interrupt_handler (frame->next->pc)))
|
||
{
|
||
struct frame_info *fi;
|
||
struct frame_saved_regs saved_regs;
|
||
|
||
fi = get_frame_info (frame->next);
|
||
get_frame_saved_regs (fi, &saved_regs);
|
||
if (read_memory_integer (saved_regs.regs[FLAGS_REGNUM] & 0x2, 4))
|
||
pc = read_memory_integer (saved_regs.regs[31], 4) & ~0x3;
|
||
else
|
||
pc = read_memory_integer (saved_regs.regs[RP_REGNUM], 4) & ~0x3;
|
||
}
|
||
else if (rp_offset == 0)
|
||
pc = read_register (RP_REGNUM) & ~0x3;
|
||
else
|
||
pc = read_memory_integer (frame->frame + rp_offset, 4) & ~0x3;
|
||
}
|
||
|
||
/* If PC is inside a linker stub, then dig out the address the stub
|
||
will return to. */
|
||
u = find_unwind_entry (pc);
|
||
if (u && u->stub_type != 0)
|
||
goto restart;
|
||
|
||
return pc;
|
||
}
|
||
|
||
/* We need to correct the PC and the FP for the outermost frame when we are
|
||
in a system call. */
|
||
|
||
void
|
||
init_extra_frame_info (fromleaf, frame)
|
||
int fromleaf;
|
||
struct frame_info *frame;
|
||
{
|
||
int flags;
|
||
int framesize;
|
||
|
||
if (frame->next && !fromleaf)
|
||
return;
|
||
|
||
/* If the next frame represents a frameless function invocation
|
||
then we have to do some adjustments that are normally done by
|
||
FRAME_CHAIN. (FRAME_CHAIN is not called in this case.) */
|
||
if (fromleaf)
|
||
{
|
||
/* Find the framesize of *this* frame without peeking at the PC
|
||
in the current frame structure (it isn't set yet). */
|
||
framesize = find_proc_framesize (FRAME_SAVED_PC (get_next_frame (frame)));
|
||
|
||
/* Now adjust our base frame accordingly. If we have a frame pointer
|
||
use it, else subtract the size of this frame from the current
|
||
frame. (we always want frame->frame to point at the lowest address
|
||
in the frame). */
|
||
if (framesize == -1)
|
||
frame->frame = read_register (FP_REGNUM);
|
||
else
|
||
frame->frame -= framesize;
|
||
return;
|
||
}
|
||
|
||
flags = read_register (FLAGS_REGNUM);
|
||
if (flags & 2) /* In system call? */
|
||
frame->pc = read_register (31) & ~0x3;
|
||
|
||
/* The outermost frame is always derived from PC-framesize
|
||
|
||
One might think frameless innermost frames should have
|
||
a frame->frame that is the same as the parent's frame->frame.
|
||
That is wrong; frame->frame in that case should be the *high*
|
||
address of the parent's frame. It's complicated as hell to
|
||
explain, but the parent *always* creates some stack space for
|
||
the child. So the child actually does have a frame of some
|
||
sorts, and its base is the high address in its parent's frame. */
|
||
framesize = find_proc_framesize(frame->pc);
|
||
if (framesize == -1)
|
||
frame->frame = read_register (FP_REGNUM);
|
||
else
|
||
frame->frame = read_register (SP_REGNUM) - framesize;
|
||
}
|
||
|
||
/* Given a GDB frame, determine the address of the calling function's frame.
|
||
This will be used to create a new GDB frame struct, and then
|
||
INIT_EXTRA_FRAME_INFO and INIT_FRAME_PC will be called for the new frame.
|
||
|
||
This may involve searching through prologues for several functions
|
||
at boundaries where GCC calls HP C code, or where code which has
|
||
a frame pointer calls code without a frame pointer. */
|
||
|
||
|
||
FRAME_ADDR
|
||
frame_chain (frame)
|
||
struct frame_info *frame;
|
||
{
|
||
int my_framesize, caller_framesize;
|
||
struct unwind_table_entry *u;
|
||
CORE_ADDR frame_base;
|
||
|
||
/* Handle HPUX, BSD, and OSF1 style interrupt frames first. These
|
||
are easy; at *sp we have a full save state strucutre which we can
|
||
pull the old stack pointer from. Also see frame_saved_pc for
|
||
code to dig a saved PC out of the save state structure. */
|
||
if (pc_in_interrupt_handler (frame->pc))
|
||
frame_base = read_memory_integer (frame->frame + SP_REGNUM * 4, 4);
|
||
else if (frame->signal_handler_caller)
|
||
{
|
||
FRAME_BASE_BEFORE_SIGTRAMP (frame, &frame_base);
|
||
}
|
||
else
|
||
frame_base = frame->frame;
|
||
|
||
/* Get frame sizes for the current frame and the frame of the
|
||
caller. */
|
||
my_framesize = find_proc_framesize (frame->pc);
|
||
caller_framesize = find_proc_framesize (FRAME_SAVED_PC(frame));
|
||
|
||
/* If caller does not have a frame pointer, then its frame
|
||
can be found at current_frame - caller_framesize. */
|
||
if (caller_framesize != -1)
|
||
return frame_base - caller_framesize;
|
||
|
||
/* Both caller and callee have frame pointers and are GCC compiled
|
||
(SAVE_SP bit in unwind descriptor is on for both functions.
|
||
The previous frame pointer is found at the top of the current frame. */
|
||
if (caller_framesize == -1 && my_framesize == -1)
|
||
return read_memory_integer (frame_base, 4);
|
||
|
||
/* Caller has a frame pointer, but callee does not. This is a little
|
||
more difficult as GCC and HP C lay out locals and callee register save
|
||
areas very differently.
|
||
|
||
The previous frame pointer could be in a register, or in one of
|
||
several areas on the stack.
|
||
|
||
Walk from the current frame to the innermost frame examining
|
||
unwind descriptors to determine if %r3 ever gets saved into the
|
||
stack. If so return whatever value got saved into the stack.
|
||
If it was never saved in the stack, then the value in %r3 is still
|
||
valid, so use it.
|
||
|
||
We use information from unwind descriptors to determine if %r3
|
||
is saved into the stack (Entry_GR field has this information). */
|
||
|
||
while (frame)
|
||
{
|
||
u = find_unwind_entry (frame->pc);
|
||
|
||
if (!u)
|
||
{
|
||
/* We could find this information by examining prologues. I don't
|
||
think anyone has actually written any tools (not even "strip")
|
||
which leave them out of an executable, so maybe this is a moot
|
||
point. */
|
||
warning ("Unable to find unwind for PC 0x%x -- Help!", frame->pc);
|
||
return 0;
|
||
}
|
||
|
||
/* Entry_GR specifies the number of callee-saved general registers
|
||
saved in the stack. It starts at %r3, so %r3 would be 1. */
|
||
if (u->Entry_GR >= 1 || u->Save_SP
|
||
|| frame->signal_handler_caller
|
||
|| pc_in_interrupt_handler (frame->pc))
|
||
break;
|
||
else
|
||
frame = frame->next;
|
||
}
|
||
|
||
if (frame)
|
||
{
|
||
/* We may have walked down the chain into a function with a frame
|
||
pointer. */
|
||
if (u->Save_SP
|
||
&& !frame->signal_handler_caller
|
||
&& !pc_in_interrupt_handler (frame->pc))
|
||
return read_memory_integer (frame->frame, 4);
|
||
/* %r3 was saved somewhere in the stack. Dig it out. */
|
||
else
|
||
{
|
||
struct frame_info *fi;
|
||
struct frame_saved_regs saved_regs;
|
||
|
||
fi = get_frame_info (frame);
|
||
get_frame_saved_regs (fi, &saved_regs);
|
||
return read_memory_integer (saved_regs.regs[FP_REGNUM], 4);
|
||
}
|
||
}
|
||
else
|
||
{
|
||
/* The value in %r3 was never saved into the stack (thus %r3 still
|
||
holds the value of the previous frame pointer). */
|
||
return read_register (FP_REGNUM);
|
||
}
|
||
}
|
||
|
||
|
||
/* To see if a frame chain is valid, see if the caller looks like it
|
||
was compiled with gcc. */
|
||
|
||
int
|
||
frame_chain_valid (chain, thisframe)
|
||
FRAME_ADDR chain;
|
||
FRAME thisframe;
|
||
{
|
||
struct minimal_symbol *msym_us;
|
||
struct minimal_symbol *msym_start;
|
||
struct unwind_table_entry *u, *next_u = NULL;
|
||
FRAME next;
|
||
|
||
if (!chain)
|
||
return 0;
|
||
|
||
u = find_unwind_entry (thisframe->pc);
|
||
|
||
if (u == NULL)
|
||
return 1;
|
||
|
||
/* We can't just check that the same of msym_us is "_start", because
|
||
someone idiotically decided that they were going to make a Ltext_end
|
||
symbol with the same address. This Ltext_end symbol is totally
|
||
indistinguishable (as nearly as I can tell) from the symbol for a function
|
||
which is (legitimately, since it is in the user's namespace)
|
||
named Ltext_end, so we can't just ignore it. */
|
||
msym_us = lookup_minimal_symbol_by_pc (FRAME_SAVED_PC (thisframe));
|
||
msym_start = lookup_minimal_symbol ("_start", NULL);
|
||
if (msym_us
|
||
&& msym_start
|
||
&& SYMBOL_VALUE_ADDRESS (msym_us) == SYMBOL_VALUE_ADDRESS (msym_start))
|
||
return 0;
|
||
|
||
next = get_next_frame (thisframe);
|
||
if (next)
|
||
next_u = find_unwind_entry (next->pc);
|
||
|
||
/* If this frame does not save SP, has no stack, isn't a stub,
|
||
and doesn't "call" an interrupt routine or signal handler caller,
|
||
then its not valid. */
|
||
if (u->Save_SP || u->Total_frame_size || u->stub_type != 0
|
||
|| (thisframe->next && thisframe->next->signal_handler_caller)
|
||
|| (next_u && next_u->HP_UX_interrupt_marker))
|
||
return 1;
|
||
|
||
if (pc_in_linker_stub (thisframe->pc))
|
||
return 1;
|
||
|
||
return 0;
|
||
}
|
||
|
||
/*
|
||
* These functions deal with saving and restoring register state
|
||
* around a function call in the inferior. They keep the stack
|
||
* double-word aligned; eventually, on an hp700, the stack will have
|
||
* to be aligned to a 64-byte boundary.
|
||
*/
|
||
|
||
int
|
||
push_dummy_frame ()
|
||
{
|
||
register CORE_ADDR sp;
|
||
register int regnum;
|
||
int int_buffer;
|
||
double freg_buffer;
|
||
|
||
/* Space for "arguments"; the RP goes in here. */
|
||
sp = read_register (SP_REGNUM) + 48;
|
||
int_buffer = read_register (RP_REGNUM) | 0x3;
|
||
write_memory (sp - 20, (char *)&int_buffer, 4);
|
||
|
||
int_buffer = read_register (FP_REGNUM);
|
||
write_memory (sp, (char *)&int_buffer, 4);
|
||
|
||
write_register (FP_REGNUM, sp);
|
||
|
||
sp += 8;
|
||
|
||
for (regnum = 1; regnum < 32; regnum++)
|
||
if (regnum != RP_REGNUM && regnum != FP_REGNUM)
|
||
sp = push_word (sp, read_register (regnum));
|
||
|
||
sp += 4;
|
||
|
||
for (regnum = FP0_REGNUM; regnum < NUM_REGS; regnum++)
|
||
{
|
||
read_register_bytes (REGISTER_BYTE (regnum), (char *)&freg_buffer, 8);
|
||
sp = push_bytes (sp, (char *)&freg_buffer, 8);
|
||
}
|
||
sp = push_word (sp, read_register (IPSW_REGNUM));
|
||
sp = push_word (sp, read_register (SAR_REGNUM));
|
||
sp = push_word (sp, read_register (PCOQ_HEAD_REGNUM));
|
||
sp = push_word (sp, read_register (PCSQ_HEAD_REGNUM));
|
||
sp = push_word (sp, read_register (PCOQ_TAIL_REGNUM));
|
||
sp = push_word (sp, read_register (PCSQ_TAIL_REGNUM));
|
||
write_register (SP_REGNUM, sp);
|
||
}
|
||
|
||
find_dummy_frame_regs (frame, frame_saved_regs)
|
||
struct frame_info *frame;
|
||
struct frame_saved_regs *frame_saved_regs;
|
||
{
|
||
CORE_ADDR fp = frame->frame;
|
||
int i;
|
||
|
||
frame_saved_regs->regs[RP_REGNUM] = fp - 20 & ~0x3;
|
||
frame_saved_regs->regs[FP_REGNUM] = fp;
|
||
frame_saved_regs->regs[1] = fp + 8;
|
||
|
||
for (fp += 12, i = 3; i < 32; i++)
|
||
{
|
||
if (i != FP_REGNUM)
|
||
{
|
||
frame_saved_regs->regs[i] = fp;
|
||
fp += 4;
|
||
}
|
||
}
|
||
|
||
fp += 4;
|
||
for (i = FP0_REGNUM; i < NUM_REGS; i++, fp += 8)
|
||
frame_saved_regs->regs[i] = fp;
|
||
|
||
frame_saved_regs->regs[IPSW_REGNUM] = fp;
|
||
frame_saved_regs->regs[SAR_REGNUM] = fp + 4;
|
||
frame_saved_regs->regs[PCOQ_HEAD_REGNUM] = fp + 8;
|
||
frame_saved_regs->regs[PCSQ_HEAD_REGNUM] = fp + 12;
|
||
frame_saved_regs->regs[PCOQ_TAIL_REGNUM] = fp + 16;
|
||
frame_saved_regs->regs[PCSQ_TAIL_REGNUM] = fp + 20;
|
||
}
|
||
|
||
int
|
||
hppa_pop_frame ()
|
||
{
|
||
register FRAME frame = get_current_frame ();
|
||
register CORE_ADDR fp;
|
||
register int regnum;
|
||
struct frame_saved_regs fsr;
|
||
struct frame_info *fi;
|
||
double freg_buffer;
|
||
|
||
fi = get_frame_info (frame);
|
||
fp = fi->frame;
|
||
get_frame_saved_regs (fi, &fsr);
|
||
|
||
#ifndef NO_PC_SPACE_QUEUE_RESTORE
|
||
if (fsr.regs[IPSW_REGNUM]) /* Restoring a call dummy frame */
|
||
restore_pc_queue (&fsr);
|
||
#endif
|
||
|
||
for (regnum = 31; regnum > 0; regnum--)
|
||
if (fsr.regs[regnum])
|
||
write_register (regnum, read_memory_integer (fsr.regs[regnum], 4));
|
||
|
||
for (regnum = NUM_REGS - 1; regnum >= FP0_REGNUM ; regnum--)
|
||
if (fsr.regs[regnum])
|
||
{
|
||
read_memory (fsr.regs[regnum], (char *)&freg_buffer, 8);
|
||
write_register_bytes (REGISTER_BYTE (regnum), (char *)&freg_buffer, 8);
|
||
}
|
||
|
||
if (fsr.regs[IPSW_REGNUM])
|
||
write_register (IPSW_REGNUM,
|
||
read_memory_integer (fsr.regs[IPSW_REGNUM], 4));
|
||
|
||
if (fsr.regs[SAR_REGNUM])
|
||
write_register (SAR_REGNUM,
|
||
read_memory_integer (fsr.regs[SAR_REGNUM], 4));
|
||
|
||
/* If the PC was explicitly saved, then just restore it. */
|
||
if (fsr.regs[PCOQ_TAIL_REGNUM])
|
||
write_register (PCOQ_TAIL_REGNUM,
|
||
read_memory_integer (fsr.regs[PCOQ_TAIL_REGNUM], 4));
|
||
|
||
/* Else use the value in %rp to set the new PC. */
|
||
else
|
||
target_write_pc (read_register (RP_REGNUM));
|
||
|
||
write_register (FP_REGNUM, read_memory_integer (fp, 4));
|
||
|
||
if (fsr.regs[IPSW_REGNUM]) /* call dummy */
|
||
write_register (SP_REGNUM, fp - 48);
|
||
else
|
||
write_register (SP_REGNUM, fp);
|
||
|
||
flush_cached_frames ();
|
||
set_current_frame (create_new_frame (read_register (FP_REGNUM),
|
||
read_pc ()));
|
||
}
|
||
|
||
/*
|
||
* After returning to a dummy on the stack, restore the instruction
|
||
* queue space registers. */
|
||
|
||
static int
|
||
restore_pc_queue (fsr)
|
||
struct frame_saved_regs *fsr;
|
||
{
|
||
CORE_ADDR pc = read_pc ();
|
||
CORE_ADDR new_pc = read_memory_integer (fsr->regs[PCOQ_HEAD_REGNUM], 4);
|
||
int pid;
|
||
struct target_waitstatus w;
|
||
int insn_count;
|
||
|
||
/* Advance past break instruction in the call dummy. */
|
||
write_register (PCOQ_HEAD_REGNUM, pc + 4);
|
||
write_register (PCOQ_TAIL_REGNUM, pc + 8);
|
||
|
||
/*
|
||
* HPUX doesn't let us set the space registers or the space
|
||
* registers of the PC queue through ptrace. Boo, hiss.
|
||
* Conveniently, the call dummy has this sequence of instructions
|
||
* after the break:
|
||
* mtsp r21, sr0
|
||
* ble,n 0(sr0, r22)
|
||
*
|
||
* So, load up the registers and single step until we are in the
|
||
* right place.
|
||
*/
|
||
|
||
write_register (21, read_memory_integer (fsr->regs[PCSQ_HEAD_REGNUM], 4));
|
||
write_register (22, new_pc);
|
||
|
||
for (insn_count = 0; insn_count < 3; insn_count++)
|
||
{
|
||
/* FIXME: What if the inferior gets a signal right now? Want to
|
||
merge this into wait_for_inferior (as a special kind of
|
||
watchpoint? By setting a breakpoint at the end? Is there
|
||
any other choice? Is there *any* way to do this stuff with
|
||
ptrace() or some equivalent?). */
|
||
resume (1, 0);
|
||
target_wait (inferior_pid, &w);
|
||
|
||
if (w.kind == TARGET_WAITKIND_SIGNALLED)
|
||
{
|
||
stop_signal = w.value.sig;
|
||
terminal_ours_for_output ();
|
||
printf_unfiltered ("\nProgram terminated with signal %s, %s.\n",
|
||
target_signal_to_name (stop_signal),
|
||
target_signal_to_string (stop_signal));
|
||
gdb_flush (gdb_stdout);
|
||
return 0;
|
||
}
|
||
}
|
||
target_terminal_ours ();
|
||
(current_target->to_fetch_registers) (-1);
|
||
return 1;
|
||
}
|
||
|
||
CORE_ADDR
|
||
hppa_push_arguments (nargs, args, sp, struct_return, struct_addr)
|
||
int nargs;
|
||
value_ptr *args;
|
||
CORE_ADDR sp;
|
||
int struct_return;
|
||
CORE_ADDR struct_addr;
|
||
{
|
||
/* array of arguments' offsets */
|
||
int *offset = (int *)alloca(nargs * sizeof (int));
|
||
int cum = 0;
|
||
int i, alignment;
|
||
|
||
for (i = 0; i < nargs; i++)
|
||
{
|
||
/* Coerce chars to int & float to double if necessary */
|
||
args[i] = value_arg_coerce (args[i]);
|
||
|
||
cum += TYPE_LENGTH (VALUE_TYPE (args[i]));
|
||
|
||
/* value must go at proper alignment. Assume alignment is a
|
||
power of two.*/
|
||
alignment = hppa_alignof (VALUE_TYPE (args[i]));
|
||
if (cum % alignment)
|
||
cum = (cum + alignment) & -alignment;
|
||
offset[i] = -cum;
|
||
}
|
||
sp += max ((cum + 7) & -8, 16);
|
||
|
||
for (i = 0; i < nargs; i++)
|
||
write_memory (sp + offset[i], VALUE_CONTENTS (args[i]),
|
||
TYPE_LENGTH (VALUE_TYPE (args[i])));
|
||
|
||
if (struct_return)
|
||
write_register (28, struct_addr);
|
||
return sp + 32;
|
||
}
|
||
|
||
/*
|
||
* Insert the specified number of args and function address
|
||
* into a call sequence of the above form stored at DUMMYNAME.
|
||
*
|
||
* On the hppa we need to call the stack dummy through $$dyncall.
|
||
* Therefore our version of FIX_CALL_DUMMY takes an extra argument,
|
||
* real_pc, which is the location where gdb should start up the
|
||
* inferior to do the function call.
|
||
*/
|
||
|
||
CORE_ADDR
|
||
hppa_fix_call_dummy (dummy, pc, fun, nargs, args, type, gcc_p)
|
||
char *dummy;
|
||
CORE_ADDR pc;
|
||
CORE_ADDR fun;
|
||
int nargs;
|
||
value_ptr *args;
|
||
struct type *type;
|
||
int gcc_p;
|
||
{
|
||
CORE_ADDR dyncall_addr, sr4export_addr;
|
||
struct minimal_symbol *msymbol;
|
||
int flags = read_register (FLAGS_REGNUM);
|
||
struct unwind_table_entry *u;
|
||
|
||
msymbol = lookup_minimal_symbol ("$$dyncall", (struct objfile *) NULL);
|
||
if (msymbol == NULL)
|
||
error ("Can't find an address for $$dyncall trampoline");
|
||
|
||
dyncall_addr = SYMBOL_VALUE_ADDRESS (msymbol);
|
||
|
||
/* FUN could be a procedure label, in which case we have to get
|
||
its real address and the value of its GOT/DP. */
|
||
if (fun & 0x2)
|
||
{
|
||
/* Get the GOT/DP value for the target function. It's
|
||
at *(fun+4). Note the call dummy is *NOT* allowed to
|
||
trash %r19 before calling the target function. */
|
||
write_register (19, read_memory_integer ((fun & ~0x3) + 4, 4));
|
||
|
||
/* Now get the real address for the function we are calling, it's
|
||
at *fun. */
|
||
fun = (CORE_ADDR) read_memory_integer (fun & ~0x3, 4);
|
||
}
|
||
|
||
/* If we are calling an import stub (eg calling into a dynamic library)
|
||
then have sr4export call the magic __d_plt_call routine which is linked
|
||
in from end.o. (You can't use _sr4export to call the import stub as
|
||
the value in sp-24 will get fried and you end up returning to the
|
||
wrong location. You can't call the import stub directly as the code
|
||
to bind the PLT entry to a function can't return to a stack address.) */
|
||
u = find_unwind_entry (fun);
|
||
if (u && u->stub_type == IMPORT)
|
||
{
|
||
CORE_ADDR new_fun;
|
||
msymbol = lookup_minimal_symbol ("__d_plt_call", (struct objfile *) NULL);
|
||
if (msymbol == NULL)
|
||
error ("Can't find an address for __d_plt_call trampoline");
|
||
|
||
/* This is where sr4export will jump to. */
|
||
new_fun = SYMBOL_VALUE_ADDRESS (msymbol);
|
||
|
||
/* We have to store the address of the stub in __shlib_funcptr. */
|
||
msymbol = lookup_minimal_symbol ("__shlib_funcptr",
|
||
(struct objfile *)NULL);
|
||
if (msymbol == NULL)
|
||
error ("Can't find an address for __shlib_funcptr");
|
||
|
||
target_write_memory (SYMBOL_VALUE_ADDRESS (msymbol), (char *)&fun, 4);
|
||
fun = new_fun;
|
||
|
||
}
|
||
|
||
/* We still need sr4export's address too. */
|
||
msymbol = lookup_minimal_symbol ("_sr4export", (struct objfile *) NULL);
|
||
if (msymbol == NULL)
|
||
error ("Can't find an address for _sr4export trampoline");
|
||
|
||
sr4export_addr = SYMBOL_VALUE_ADDRESS (msymbol);
|
||
|
||
store_unsigned_integer
|
||
(&dummy[9*REGISTER_SIZE],
|
||
REGISTER_SIZE,
|
||
deposit_21 (fun >> 11,
|
||
extract_unsigned_integer (&dummy[9*REGISTER_SIZE],
|
||
REGISTER_SIZE)));
|
||
store_unsigned_integer
|
||
(&dummy[10*REGISTER_SIZE],
|
||
REGISTER_SIZE,
|
||
deposit_14 (fun & MASK_11,
|
||
extract_unsigned_integer (&dummy[10*REGISTER_SIZE],
|
||
REGISTER_SIZE)));
|
||
store_unsigned_integer
|
||
(&dummy[12*REGISTER_SIZE],
|
||
REGISTER_SIZE,
|
||
deposit_21 (sr4export_addr >> 11,
|
||
extract_unsigned_integer (&dummy[12*REGISTER_SIZE],
|
||
REGISTER_SIZE)));
|
||
store_unsigned_integer
|
||
(&dummy[13*REGISTER_SIZE],
|
||
REGISTER_SIZE,
|
||
deposit_14 (sr4export_addr & MASK_11,
|
||
extract_unsigned_integer (&dummy[13*REGISTER_SIZE],
|
||
REGISTER_SIZE)));
|
||
|
||
write_register (22, pc);
|
||
|
||
/* If we are in a syscall, then we should call the stack dummy
|
||
directly. $$dyncall is not needed as the kernel sets up the
|
||
space id registers properly based on the value in %r31. In
|
||
fact calling $$dyncall will not work because the value in %r22
|
||
will be clobbered on the syscall exit path. */
|
||
if (flags & 2)
|
||
return pc;
|
||
else
|
||
return dyncall_addr;
|
||
|
||
}
|
||
|
||
/* Get the PC from %r31 if currently in a syscall. Also mask out privilege
|
||
bits. */
|
||
CORE_ADDR
|
||
target_read_pc ()
|
||
{
|
||
int flags = read_register (FLAGS_REGNUM);
|
||
|
||
if (flags & 2)
|
||
return read_register (31) & ~0x3;
|
||
return read_register (PC_REGNUM) & ~0x3;
|
||
}
|
||
|
||
/* Write out the PC. If currently in a syscall, then also write the new
|
||
PC value into %r31. */
|
||
void
|
||
target_write_pc (v)
|
||
CORE_ADDR v;
|
||
{
|
||
int flags = read_register (FLAGS_REGNUM);
|
||
|
||
/* If in a syscall, then set %r31. Also make sure to get the
|
||
privilege bits set correctly. */
|
||
if (flags & 2)
|
||
write_register (31, (long) (v | 0x3));
|
||
|
||
write_register (PC_REGNUM, (long) v);
|
||
write_register (NPC_REGNUM, (long) v + 4);
|
||
}
|
||
|
||
/* return the alignment of a type in bytes. Structures have the maximum
|
||
alignment required by their fields. */
|
||
|
||
static int
|
||
hppa_alignof (arg)
|
||
struct type *arg;
|
||
{
|
||
int max_align, align, i;
|
||
switch (TYPE_CODE (arg))
|
||
{
|
||
case TYPE_CODE_PTR:
|
||
case TYPE_CODE_INT:
|
||
case TYPE_CODE_FLT:
|
||
return TYPE_LENGTH (arg);
|
||
case TYPE_CODE_ARRAY:
|
||
return hppa_alignof (TYPE_FIELD_TYPE (arg, 0));
|
||
case TYPE_CODE_STRUCT:
|
||
case TYPE_CODE_UNION:
|
||
max_align = 2;
|
||
for (i = 0; i < TYPE_NFIELDS (arg); i++)
|
||
{
|
||
/* Bit fields have no real alignment. */
|
||
if (!TYPE_FIELD_BITPOS (arg, i))
|
||
{
|
||
align = hppa_alignof (TYPE_FIELD_TYPE (arg, i));
|
||
max_align = max (max_align, align);
|
||
}
|
||
}
|
||
return max_align;
|
||
default:
|
||
return 4;
|
||
}
|
||
}
|
||
|
||
/* Print the register regnum, or all registers if regnum is -1 */
|
||
|
||
pa_do_registers_info (regnum, fpregs)
|
||
int regnum;
|
||
int fpregs;
|
||
{
|
||
char raw_regs [REGISTER_BYTES];
|
||
int i;
|
||
|
||
for (i = 0; i < NUM_REGS; i++)
|
||
read_relative_register_raw_bytes (i, raw_regs + REGISTER_BYTE (i));
|
||
if (regnum == -1)
|
||
pa_print_registers (raw_regs, regnum, fpregs);
|
||
else if (regnum < FP0_REGNUM)
|
||
printf_unfiltered ("%s %x\n", reg_names[regnum], *(long *)(raw_regs +
|
||
REGISTER_BYTE (regnum)));
|
||
else
|
||
pa_print_fp_reg (regnum);
|
||
}
|
||
|
||
pa_print_registers (raw_regs, regnum, fpregs)
|
||
char *raw_regs;
|
||
int regnum;
|
||
int fpregs;
|
||
{
|
||
int i;
|
||
|
||
for (i = 0; i < 18; i++)
|
||
printf_unfiltered ("%8.8s: %8x %8.8s: %8x %8.8s: %8x %8.8s: %8x\n",
|
||
reg_names[i],
|
||
*(int *)(raw_regs + REGISTER_BYTE (i)),
|
||
reg_names[i + 18],
|
||
*(int *)(raw_regs + REGISTER_BYTE (i + 18)),
|
||
reg_names[i + 36],
|
||
*(int *)(raw_regs + REGISTER_BYTE (i + 36)),
|
||
reg_names[i + 54],
|
||
*(int *)(raw_regs + REGISTER_BYTE (i + 54)));
|
||
|
||
if (fpregs)
|
||
for (i = 72; i < NUM_REGS; i++)
|
||
pa_print_fp_reg (i);
|
||
}
|
||
|
||
pa_print_fp_reg (i)
|
||
int i;
|
||
{
|
||
unsigned char raw_buffer[MAX_REGISTER_RAW_SIZE];
|
||
unsigned char virtual_buffer[MAX_REGISTER_VIRTUAL_SIZE];
|
||
|
||
/* Get 32bits of data. */
|
||
read_relative_register_raw_bytes (i, raw_buffer);
|
||
|
||
/* Put it in the buffer. No conversions are ever necessary. */
|
||
memcpy (virtual_buffer, raw_buffer, REGISTER_RAW_SIZE (i));
|
||
|
||
fputs_filtered (reg_names[i], gdb_stdout);
|
||
print_spaces_filtered (8 - strlen (reg_names[i]), gdb_stdout);
|
||
fputs_filtered ("(single precision) ", gdb_stdout);
|
||
|
||
val_print (REGISTER_VIRTUAL_TYPE (i), virtual_buffer, 0, gdb_stdout, 0,
|
||
1, 0, Val_pretty_default);
|
||
printf_filtered ("\n");
|
||
|
||
/* If "i" is even, then this register can also be a double-precision
|
||
FP register. Dump it out as such. */
|
||
if ((i % 2) == 0)
|
||
{
|
||
/* Get the data in raw format for the 2nd half. */
|
||
read_relative_register_raw_bytes (i + 1, raw_buffer);
|
||
|
||
/* Copy it into the appropriate part of the virtual buffer. */
|
||
memcpy (virtual_buffer + REGISTER_RAW_SIZE (i), raw_buffer,
|
||
REGISTER_RAW_SIZE (i));
|
||
|
||
/* Dump it as a double. */
|
||
fputs_filtered (reg_names[i], gdb_stdout);
|
||
print_spaces_filtered (8 - strlen (reg_names[i]), gdb_stdout);
|
||
fputs_filtered ("(double precision) ", gdb_stdout);
|
||
|
||
val_print (builtin_type_double, virtual_buffer, 0, gdb_stdout, 0,
|
||
1, 0, Val_pretty_default);
|
||
printf_filtered ("\n");
|
||
}
|
||
}
|
||
|
||
/* Figure out if PC is in a trampoline, and if so find out where
|
||
the trampoline will jump to. If not in a trampoline, return zero.
|
||
|
||
Simple code examination probably is not a good idea since the code
|
||
sequences in trampolines can also appear in user code.
|
||
|
||
We use unwinds and information from the minimal symbol table to
|
||
determine when we're in a trampoline. This won't work for ELF
|
||
(yet) since it doesn't create stub unwind entries. Whether or
|
||
not ELF will create stub unwinds or normal unwinds for linker
|
||
stubs is still being debated.
|
||
|
||
This should handle simple calls through dyncall or sr4export,
|
||
long calls, argument relocation stubs, and dyncall/sr4export
|
||
calling an argument relocation stub. It even handles some stubs
|
||
used in dynamic executables. */
|
||
|
||
CORE_ADDR
|
||
skip_trampoline_code (pc, name)
|
||
CORE_ADDR pc;
|
||
char *name;
|
||
{
|
||
long orig_pc = pc;
|
||
long prev_inst, curr_inst, loc;
|
||
static CORE_ADDR dyncall = 0;
|
||
static CORE_ADDR sr4export = 0;
|
||
struct minimal_symbol *msym;
|
||
struct unwind_table_entry *u;
|
||
|
||
/* FIXME XXX - dyncall and sr4export must be initialized whenever we get a
|
||
new exec file */
|
||
|
||
if (!dyncall)
|
||
{
|
||
msym = lookup_minimal_symbol ("$$dyncall", NULL);
|
||
if (msym)
|
||
dyncall = SYMBOL_VALUE_ADDRESS (msym);
|
||
else
|
||
dyncall = -1;
|
||
}
|
||
|
||
if (!sr4export)
|
||
{
|
||
msym = lookup_minimal_symbol ("_sr4export", NULL);
|
||
if (msym)
|
||
sr4export = SYMBOL_VALUE_ADDRESS (msym);
|
||
else
|
||
sr4export = -1;
|
||
}
|
||
|
||
/* Addresses passed to dyncall may *NOT* be the actual address
|
||
of the funtion. So we may have to do something special. */
|
||
if (pc == dyncall)
|
||
{
|
||
pc = (CORE_ADDR) read_register (22);
|
||
|
||
/* If bit 30 (counting from the left) is on, then pc is the address of
|
||
the PLT entry for this function, not the address of the function
|
||
itself. Bit 31 has meaning too, but only for MPE. */
|
||
if (pc & 0x2)
|
||
pc = (CORE_ADDR) read_memory_integer (pc & ~0x3, 4);
|
||
}
|
||
else if (pc == sr4export)
|
||
pc = (CORE_ADDR) (read_register (22));
|
||
|
||
/* Get the unwind descriptor corresponding to PC, return zero
|
||
if no unwind was found. */
|
||
u = find_unwind_entry (pc);
|
||
if (!u)
|
||
return 0;
|
||
|
||
/* If this isn't a linker stub, then return now. */
|
||
if (u->stub_type == 0)
|
||
return orig_pc == pc ? 0 : pc & ~0x3;
|
||
|
||
/* It's a stub. Search for a branch and figure out where it goes.
|
||
Note we have to handle multi insn branch sequences like ldil;ble.
|
||
Most (all?) other branches can be determined by examining the contents
|
||
of certain registers and the stack. */
|
||
loc = pc;
|
||
curr_inst = 0;
|
||
prev_inst = 0;
|
||
while (1)
|
||
{
|
||
/* Make sure we haven't walked outside the range of this stub. */
|
||
if (u != find_unwind_entry (loc))
|
||
{
|
||
warning ("Unable to find branch in linker stub");
|
||
return orig_pc == pc ? 0 : pc & ~0x3;
|
||
}
|
||
|
||
prev_inst = curr_inst;
|
||
curr_inst = read_memory_integer (loc, 4);
|
||
|
||
/* Does it look like a branch external using %r1? Then it's the
|
||
branch from the stub to the actual function. */
|
||
if ((curr_inst & 0xffe0e000) == 0xe0202000)
|
||
{
|
||
/* Yup. See if the previous instruction loaded
|
||
a value into %r1. If so compute and return the jump address. */
|
||
if ((prev_inst & 0xffe00000) == 0x20202000)
|
||
return (extract_21 (prev_inst) + extract_17 (curr_inst)) & ~0x3;
|
||
else
|
||
{
|
||
warning ("Unable to find ldil X,%%r1 before ble Y(%%sr4,%%r1).");
|
||
return orig_pc == pc ? 0 : pc & ~0x3;
|
||
}
|
||
}
|
||
|
||
/* Does it look like bl X,rp? Another way to do a branch from the
|
||
stub to the actual function. */
|
||
else if ((curr_inst & 0xffe0e000) == 0xe8400000)
|
||
return (loc + extract_17 (curr_inst) + 8) & ~0x3;
|
||
|
||
/* Does it look like bv (rp)? Note this depends on the
|
||
current stack pointer being the same as the stack
|
||
pointer in the stub itself! This is a branch on from the
|
||
stub back to the original caller. */
|
||
else if ((curr_inst & 0xffe0e000) == 0xe840c000)
|
||
{
|
||
/* Yup. See if the previous instruction loaded
|
||
rp from sp - 8. */
|
||
if (prev_inst == 0x4bc23ff1)
|
||
return (read_memory_integer
|
||
(read_register (SP_REGNUM) - 8, 4)) & ~0x3;
|
||
else
|
||
{
|
||
warning ("Unable to find restore of %%rp before bv (%%rp).");
|
||
return orig_pc == pc ? 0 : pc & ~0x3;
|
||
}
|
||
}
|
||
|
||
/* What about be,n 0(sr0,%rp)? It's just another way we return to
|
||
the original caller from the stub. Used in dynamic executables. */
|
||
else if (curr_inst == 0xe0400002)
|
||
{
|
||
/* The value we jump to is sitting in sp - 24. But that's
|
||
loaded several instructions before the be instruction.
|
||
I guess we could check for the previous instruction being
|
||
mtsp %r1,%sr0 if we want to do sanity checking. */
|
||
return (read_memory_integer
|
||
(read_register (SP_REGNUM) - 24, 4)) & ~0x3;
|
||
}
|
||
|
||
/* Haven't found the branch yet, but we're still in the stub.
|
||
Keep looking. */
|
||
loc += 4;
|
||
}
|
||
}
|
||
|
||
/* For the given instruction (INST), return any adjustment it makes
|
||
to the stack pointer or zero for no adjustment.
|
||
|
||
This only handles instructions commonly found in prologues. */
|
||
|
||
static int
|
||
prologue_inst_adjust_sp (inst)
|
||
unsigned long inst;
|
||
{
|
||
/* This must persist across calls. */
|
||
static int save_high21;
|
||
|
||
/* The most common way to perform a stack adjustment ldo X(sp),sp */
|
||
if ((inst & 0xffffc000) == 0x37de0000)
|
||
return extract_14 (inst);
|
||
|
||
/* stwm X,D(sp) */
|
||
if ((inst & 0xffe00000) == 0x6fc00000)
|
||
return extract_14 (inst);
|
||
|
||
/* addil high21,%r1; ldo low11,(%r1),%r30)
|
||
save high bits in save_high21 for later use. */
|
||
if ((inst & 0xffe00000) == 0x28200000)
|
||
{
|
||
save_high21 = extract_21 (inst);
|
||
return 0;
|
||
}
|
||
|
||
if ((inst & 0xffff0000) == 0x343e0000)
|
||
return save_high21 + extract_14 (inst);
|
||
|
||
/* fstws as used by the HP compilers. */
|
||
if ((inst & 0xffffffe0) == 0x2fd01220)
|
||
return extract_5_load (inst);
|
||
|
||
/* No adjustment. */
|
||
return 0;
|
||
}
|
||
|
||
/* Return nonzero if INST is a branch of some kind, else return zero. */
|
||
|
||
static int
|
||
is_branch (inst)
|
||
unsigned long inst;
|
||
{
|
||
switch (inst >> 26)
|
||
{
|
||
case 0x20:
|
||
case 0x21:
|
||
case 0x22:
|
||
case 0x23:
|
||
case 0x28:
|
||
case 0x29:
|
||
case 0x2a:
|
||
case 0x2b:
|
||
case 0x30:
|
||
case 0x31:
|
||
case 0x32:
|
||
case 0x33:
|
||
case 0x38:
|
||
case 0x39:
|
||
case 0x3a:
|
||
return 1;
|
||
|
||
default:
|
||
return 0;
|
||
}
|
||
}
|
||
|
||
/* Return the register number for a GR which is saved by INST or
|
||
zero it INST does not save a GR.
|
||
|
||
Note we only care about full 32bit register stores (that's the only
|
||
kind of stores the prologue will use). */
|
||
|
||
static int
|
||
inst_saves_gr (inst)
|
||
unsigned long inst;
|
||
{
|
||
/* Does it look like a stw? */
|
||
if ((inst >> 26) == 0x1a)
|
||
return extract_5R_store (inst);
|
||
|
||
/* Does it look like a stwm? */
|
||
if ((inst >> 26) == 0x1b)
|
||
return extract_5R_store (inst);
|
||
|
||
return 0;
|
||
}
|
||
|
||
/* Return the register number for a FR which is saved by INST or
|
||
zero it INST does not save a FR.
|
||
|
||
Note we only care about full 64bit register stores (that's the only
|
||
kind of stores the prologue will use). */
|
||
|
||
static int
|
||
inst_saves_fr (inst)
|
||
unsigned long inst;
|
||
{
|
||
if ((inst & 0xfc1fffe0) == 0x2c101220)
|
||
return extract_5r_store (inst);
|
||
return 0;
|
||
}
|
||
|
||
/* Advance PC across any function entry prologue instructions
|
||
to reach some "real" code.
|
||
|
||
Use information in the unwind table to determine what exactly should
|
||
be in the prologue. */
|
||
|
||
CORE_ADDR
|
||
skip_prologue (pc)
|
||
CORE_ADDR pc;
|
||
{
|
||
char buf[4];
|
||
unsigned long inst, stack_remaining, save_gr, save_fr, save_rp, save_sp;
|
||
int status, i;
|
||
struct unwind_table_entry *u;
|
||
|
||
u = find_unwind_entry (pc);
|
||
if (!u)
|
||
return pc;
|
||
|
||
/* If we are not at the beginning of a function, then return now. */
|
||
if ((pc & ~0x3) != u->region_start)
|
||
return pc;
|
||
|
||
/* This is how much of a frame adjustment we need to account for. */
|
||
stack_remaining = u->Total_frame_size << 3;
|
||
|
||
/* Magic register saves we want to know about. */
|
||
save_rp = u->Save_RP;
|
||
save_sp = u->Save_SP;
|
||
|
||
/* Turn the Entry_GR field into a bitmask. */
|
||
save_gr = 0;
|
||
for (i = 3; i < u->Entry_GR + 3; i++)
|
||
{
|
||
/* Frame pointer gets saved into a special location. */
|
||
if (u->Save_SP && i == FP_REGNUM)
|
||
continue;
|
||
|
||
save_gr |= (1 << i);
|
||
}
|
||
|
||
/* Turn the Entry_FR field into a bitmask too. */
|
||
save_fr = 0;
|
||
for (i = 12; i < u->Entry_FR + 12; i++)
|
||
save_fr |= (1 << i);
|
||
|
||
/* Loop until we find everything of interest or hit a branch.
|
||
|
||
For unoptimized GCC code and for any HP CC code this will never ever
|
||
examine any user instructions.
|
||
|
||
For optimzied GCC code we're faced with problems. GCC will schedule
|
||
its prologue and make prologue instructions available for delay slot
|
||
filling. The end result is user code gets mixed in with the prologue
|
||
and a prologue instruction may be in the delay slot of the first branch
|
||
or call.
|
||
|
||
Some unexpected things are expected with debugging optimized code, so
|
||
we allow this routine to walk past user instructions in optimized
|
||
GCC code. */
|
||
while (save_gr || save_fr || save_rp || save_sp || stack_remaining > 0)
|
||
{
|
||
status = target_read_memory (pc, buf, 4);
|
||
inst = extract_unsigned_integer (buf, 4);
|
||
|
||
/* Yow! */
|
||
if (status != 0)
|
||
return pc;
|
||
|
||
/* Note the interesting effects of this instruction. */
|
||
stack_remaining -= prologue_inst_adjust_sp (inst);
|
||
|
||
/* There is only one instruction used for saving RP into the stack. */
|
||
if (inst == 0x6bc23fd9)
|
||
save_rp = 0;
|
||
|
||
/* This is the only way we save SP into the stack. At this time
|
||
the HP compilers never bother to save SP into the stack. */
|
||
if ((inst & 0xffffc000) == 0x6fc10000)
|
||
save_sp = 0;
|
||
|
||
/* Account for general and floating-point register saves. */
|
||
save_gr &= ~(1 << inst_saves_gr (inst));
|
||
save_fr &= ~(1 << inst_saves_fr (inst));
|
||
|
||
/* Quit if we hit any kind of branch. This can happen if a prologue
|
||
instruction is in the delay slot of the first call/branch. */
|
||
if (is_branch (inst))
|
||
break;
|
||
|
||
/* Bump the PC. */
|
||
pc += 4;
|
||
}
|
||
|
||
return pc;
|
||
}
|
||
|
||
/* Put here the code to store, into a struct frame_saved_regs,
|
||
the addresses of the saved registers of frame described by FRAME_INFO.
|
||
This includes special registers such as pc and fp saved in special
|
||
ways in the stack frame. sp is even more special:
|
||
the address we return for it IS the sp for the next frame. */
|
||
|
||
void
|
||
hppa_frame_find_saved_regs (frame_info, frame_saved_regs)
|
||
struct frame_info *frame_info;
|
||
struct frame_saved_regs *frame_saved_regs;
|
||
{
|
||
CORE_ADDR pc;
|
||
struct unwind_table_entry *u;
|
||
unsigned long inst, stack_remaining, save_gr, save_fr, save_rp, save_sp;
|
||
int status, i, reg;
|
||
char buf[4];
|
||
int fp_loc = -1;
|
||
|
||
/* Zero out everything. */
|
||
memset (frame_saved_regs, '\0', sizeof (struct frame_saved_regs));
|
||
|
||
/* Call dummy frames always look the same, so there's no need to
|
||
examine the dummy code to determine locations of saved registers;
|
||
instead, let find_dummy_frame_regs fill in the correct offsets
|
||
for the saved registers. */
|
||
if ((frame_info->pc >= frame_info->frame
|
||
&& frame_info->pc <= (frame_info->frame + CALL_DUMMY_LENGTH
|
||
+ 32 * 4 + (NUM_REGS - FP0_REGNUM) * 8
|
||
+ 6 * 4)))
|
||
find_dummy_frame_regs (frame_info, frame_saved_regs);
|
||
|
||
/* Interrupt handlers are special too. They lay out the register
|
||
state in the exact same order as the register numbers in GDB. */
|
||
if (pc_in_interrupt_handler (frame_info->pc))
|
||
{
|
||
for (i = 0; i < NUM_REGS; i++)
|
||
{
|
||
/* SP is a little special. */
|
||
if (i == SP_REGNUM)
|
||
frame_saved_regs->regs[SP_REGNUM]
|
||
= read_memory_integer (frame_info->frame + SP_REGNUM * 4, 4);
|
||
else
|
||
frame_saved_regs->regs[i] = frame_info->frame + i * 4;
|
||
}
|
||
return;
|
||
}
|
||
|
||
/* Handle signal handler callers. */
|
||
if (frame_info->signal_handler_caller)
|
||
{
|
||
FRAME_FIND_SAVED_REGS_IN_SIGTRAMP (frame_info, frame_saved_regs);
|
||
return;
|
||
}
|
||
|
||
/* Get the starting address of the function referred to by the PC
|
||
saved in frame_info. */
|
||
pc = get_pc_function_start (frame_info->pc);
|
||
|
||
/* Yow! */
|
||
u = find_unwind_entry (pc);
|
||
if (!u)
|
||
return;
|
||
|
||
/* This is how much of a frame adjustment we need to account for. */
|
||
stack_remaining = u->Total_frame_size << 3;
|
||
|
||
/* Magic register saves we want to know about. */
|
||
save_rp = u->Save_RP;
|
||
save_sp = u->Save_SP;
|
||
|
||
/* Turn the Entry_GR field into a bitmask. */
|
||
save_gr = 0;
|
||
for (i = 3; i < u->Entry_GR + 3; i++)
|
||
{
|
||
/* Frame pointer gets saved into a special location. */
|
||
if (u->Save_SP && i == FP_REGNUM)
|
||
continue;
|
||
|
||
save_gr |= (1 << i);
|
||
}
|
||
|
||
/* Turn the Entry_FR field into a bitmask too. */
|
||
save_fr = 0;
|
||
for (i = 12; i < u->Entry_FR + 12; i++)
|
||
save_fr |= (1 << i);
|
||
|
||
/* The frame always represents the value of %sp at entry to the
|
||
current function (and is thus equivalent to the "saved" stack
|
||
pointer. */
|
||
frame_saved_regs->regs[SP_REGNUM] = frame_info->frame;
|
||
|
||
/* Loop until we find everything of interest or hit a branch.
|
||
|
||
For unoptimized GCC code and for any HP CC code this will never ever
|
||
examine any user instructions.
|
||
|
||
For optimzied GCC code we're faced with problems. GCC will schedule
|
||
its prologue and make prologue instructions available for delay slot
|
||
filling. The end result is user code gets mixed in with the prologue
|
||
and a prologue instruction may be in the delay slot of the first branch
|
||
or call.
|
||
|
||
Some unexpected things are expected with debugging optimized code, so
|
||
we allow this routine to walk past user instructions in optimized
|
||
GCC code. */
|
||
while (save_gr || save_fr || save_rp || save_sp || stack_remaining > 0)
|
||
{
|
||
status = target_read_memory (pc, buf, 4);
|
||
inst = extract_unsigned_integer (buf, 4);
|
||
|
||
/* Yow! */
|
||
if (status != 0)
|
||
return;
|
||
|
||
/* Note the interesting effects of this instruction. */
|
||
stack_remaining -= prologue_inst_adjust_sp (inst);
|
||
|
||
/* There is only one instruction used for saving RP into the stack. */
|
||
if (inst == 0x6bc23fd9)
|
||
{
|
||
save_rp = 0;
|
||
frame_saved_regs->regs[RP_REGNUM] = frame_info->frame - 20;
|
||
}
|
||
|
||
/* Just note that we found the save of SP into the stack. The
|
||
value for frame_saved_regs was computed above. */
|
||
if ((inst & 0xffffc000) == 0x6fc10000)
|
||
save_sp = 0;
|
||
|
||
/* Account for general and floating-point register saves. */
|
||
reg = inst_saves_gr (inst);
|
||
if (reg >= 3 && reg <= 18
|
||
&& (!u->Save_SP || reg != FP_REGNUM))
|
||
{
|
||
save_gr &= ~(1 << reg);
|
||
|
||
/* stwm with a positive displacement is a *post modify*. */
|
||
if ((inst >> 26) == 0x1b
|
||
&& extract_14 (inst) >= 0)
|
||
frame_saved_regs->regs[reg] = frame_info->frame;
|
||
else
|
||
{
|
||
/* Handle code with and without frame pointers. */
|
||
if (u->Save_SP)
|
||
frame_saved_regs->regs[reg]
|
||
= frame_info->frame + extract_14 (inst);
|
||
else
|
||
frame_saved_regs->regs[reg]
|
||
= frame_info->frame + (u->Total_frame_size << 3)
|
||
+ extract_14 (inst);
|
||
}
|
||
}
|
||
|
||
|
||
/* GCC handles callee saved FP regs a little differently.
|
||
|
||
It emits an instruction to put the value of the start of
|
||
the FP store area into %r1. It then uses fstds,ma with
|
||
a basereg of %r1 for the stores.
|
||
|
||
HP CC emits them at the current stack pointer modifying
|
||
the stack pointer as it stores each register. */
|
||
|
||
/* ldo X(%r3),%r1 or ldo X(%r30),%r1. */
|
||
if ((inst & 0xffffc000) == 0x34610000
|
||
|| (inst & 0xffffc000) == 0x37c10000)
|
||
fp_loc = extract_14 (inst);
|
||
|
||
reg = inst_saves_fr (inst);
|
||
if (reg >= 12 && reg <= 21)
|
||
{
|
||
/* Note +4 braindamage below is necessary because the FP status
|
||
registers are internally 8 registers rather than the expected
|
||
4 registers. */
|
||
save_fr &= ~(1 << reg);
|
||
if (fp_loc == -1)
|
||
{
|
||
/* 1st HP CC FP register store. After this instruction
|
||
we've set enough state that the GCC and HPCC code are
|
||
both handled in the same manner. */
|
||
frame_saved_regs->regs[reg + FP4_REGNUM + 4] = frame_info->frame;
|
||
fp_loc = 8;
|
||
}
|
||
else
|
||
{
|
||
frame_saved_regs->regs[reg + FP0_REGNUM + 4]
|
||
= frame_info->frame + fp_loc;
|
||
fp_loc += 8;
|
||
}
|
||
}
|
||
|
||
/* Quit if we hit any kind of branch. This can happen if a prologue
|
||
instruction is in the delay slot of the first call/branch. */
|
||
if (is_branch (inst))
|
||
break;
|
||
|
||
/* Bump the PC. */
|
||
pc += 4;
|
||
}
|
||
}
|
||
|
||
#ifdef MAINTENANCE_CMDS
|
||
|
||
static void
|
||
unwind_command (exp, from_tty)
|
||
char *exp;
|
||
int from_tty;
|
||
{
|
||
CORE_ADDR address;
|
||
union
|
||
{
|
||
int *foo;
|
||
struct unwind_table_entry *u;
|
||
} xxx;
|
||
|
||
/* If we have an expression, evaluate it and use it as the address. */
|
||
|
||
if (exp != 0 && *exp != 0)
|
||
address = parse_and_eval_address (exp);
|
||
else
|
||
return;
|
||
|
||
xxx.u = find_unwind_entry (address);
|
||
|
||
if (!xxx.u)
|
||
{
|
||
printf_unfiltered ("Can't find unwind table entry for PC 0x%x\n", address);
|
||
return;
|
||
}
|
||
|
||
printf_unfiltered ("%08x\n%08X\n%08X\n%08X\n", xxx.foo[0], xxx.foo[1], xxx.foo[2],
|
||
xxx.foo[3]);
|
||
}
|
||
#endif /* MAINTENANCE_CMDS */
|
||
|
||
void
|
||
_initialize_hppa_tdep ()
|
||
{
|
||
#ifdef MAINTENANCE_CMDS
|
||
add_cmd ("unwind", class_maintenance, unwind_command,
|
||
"Print unwind table entry at given address.",
|
||
&maintenanceprintlist);
|
||
#endif /* MAINTENANCE_CMDS */
|
||
}
|