4be87837a2
GDB_OSABI_UNINITIALIZED. * gdbarch.sh: Add osabi to struct gdbarch and to struct gdbarch_info. Include "osabi.h" in gdbarch.c. Check osabi in gdbarch_list_lookup_by_info and in gdbarch_update_p. * gdbarch.c: Regenerated. * gdbarch.h: Regenerated. * osabi.c (gdbarch_lookup_osabi): Return GDB_OSABI_UNINITIALIZED if there's no BFD. (gdbarch_init_osabi): Remove osabi argument; use info.osabi. * osabi.h (enum gdb_osabi): Move to defs.h. (gdbarch_init_osabi): Update prototype. * defs.h (enum gdb_osabi): Moved here. * Makefile.in: Update dependencies. Plus updates to alpha, arm, hppa, i386, mips, ns32k, ppc, sh, sparc, and vax ports to match.
733 lines
24 KiB
C
733 lines
24 KiB
C
/* Target-dependent code for GDB, the GNU debugger.
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Copyright 1986, 1987, 1989, 1991, 1992, 1993, 1994, 1995, 1996,
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1997, 2000, 2001, 2002, 2003 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 "symtab.h"
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#include "target.h"
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#include "gdbcore.h"
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#include "gdbcmd.h"
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#include "symfile.h"
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#include "objfiles.h"
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#include "regcache.h"
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#include "value.h"
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#include "osabi.h"
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#include "solib-svr4.h"
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#include "ppc-tdep.h"
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/* The following two instructions are used in the signal trampoline
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code on GNU/Linux PPC. */
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#define INSTR_LI_R0_0x7777 0x38007777
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#define INSTR_SC 0x44000002
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/* Since the *-tdep.c files are platform independent (i.e, they may be
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used to build cross platform debuggers), we can't include system
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headers. Therefore, details concerning the sigcontext structure
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must be painstakingly rerecorded. What's worse, if these details
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ever change in the header files, they'll have to be changed here
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as well. */
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/* __SIGNAL_FRAMESIZE from <asm/ptrace.h> */
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#define PPC_LINUX_SIGNAL_FRAMESIZE 64
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/* From <asm/sigcontext.h>, offsetof(struct sigcontext_struct, regs) == 0x1c */
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#define PPC_LINUX_REGS_PTR_OFFSET (PPC_LINUX_SIGNAL_FRAMESIZE + 0x1c)
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/* From <asm/sigcontext.h>,
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offsetof(struct sigcontext_struct, handler) == 0x14 */
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#define PPC_LINUX_HANDLER_PTR_OFFSET (PPC_LINUX_SIGNAL_FRAMESIZE + 0x14)
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/* From <asm/ptrace.h>, values for PT_NIP, PT_R1, and PT_LNK */
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#define PPC_LINUX_PT_R0 0
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#define PPC_LINUX_PT_R1 1
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#define PPC_LINUX_PT_R2 2
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#define PPC_LINUX_PT_R3 3
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#define PPC_LINUX_PT_R4 4
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#define PPC_LINUX_PT_R5 5
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#define PPC_LINUX_PT_R6 6
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#define PPC_LINUX_PT_R7 7
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#define PPC_LINUX_PT_R8 8
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#define PPC_LINUX_PT_R9 9
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#define PPC_LINUX_PT_R10 10
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#define PPC_LINUX_PT_R11 11
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#define PPC_LINUX_PT_R12 12
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#define PPC_LINUX_PT_R13 13
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#define PPC_LINUX_PT_R14 14
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#define PPC_LINUX_PT_R15 15
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#define PPC_LINUX_PT_R16 16
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#define PPC_LINUX_PT_R17 17
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#define PPC_LINUX_PT_R18 18
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#define PPC_LINUX_PT_R19 19
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#define PPC_LINUX_PT_R20 20
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#define PPC_LINUX_PT_R21 21
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#define PPC_LINUX_PT_R22 22
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#define PPC_LINUX_PT_R23 23
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#define PPC_LINUX_PT_R24 24
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#define PPC_LINUX_PT_R25 25
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#define PPC_LINUX_PT_R26 26
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#define PPC_LINUX_PT_R27 27
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#define PPC_LINUX_PT_R28 28
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#define PPC_LINUX_PT_R29 29
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#define PPC_LINUX_PT_R30 30
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#define PPC_LINUX_PT_R31 31
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#define PPC_LINUX_PT_NIP 32
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#define PPC_LINUX_PT_MSR 33
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#define PPC_LINUX_PT_CTR 35
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#define PPC_LINUX_PT_LNK 36
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#define PPC_LINUX_PT_XER 37
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#define PPC_LINUX_PT_CCR 38
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#define PPC_LINUX_PT_MQ 39
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#define PPC_LINUX_PT_FPR0 48 /* each FP reg occupies 2 slots in this space */
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#define PPC_LINUX_PT_FPR31 (PPC_LINUX_PT_FPR0 + 2*31)
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#define PPC_LINUX_PT_FPSCR (PPC_LINUX_PT_FPR0 + 2*32 + 1)
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static int ppc_linux_at_sigtramp_return_path (CORE_ADDR pc);
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/* Determine if pc is in a signal trampoline...
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Ha! That's not what this does at all. wait_for_inferior in
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infrun.c calls PC_IN_SIGTRAMP in order to detect entry into a
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signal trampoline just after delivery of a signal. But on
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GNU/Linux, signal trampolines are used for the return path only.
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The kernel sets things up so that the signal handler is called
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directly.
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If we use in_sigtramp2() in place of in_sigtramp() (see below)
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we'll (often) end up with stop_pc in the trampoline and prev_pc in
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the (now exited) handler. The code there will cause a temporary
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breakpoint to be set on prev_pc which is not very likely to get hit
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again.
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If this is confusing, think of it this way... the code in
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wait_for_inferior() needs to be able to detect entry into a signal
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trampoline just after a signal is delivered, not after the handler
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has been run.
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So, we define in_sigtramp() below to return 1 if the following is
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true:
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1) The previous frame is a real signal trampoline.
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- and -
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2) pc is at the first or second instruction of the corresponding
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handler.
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Why the second instruction? It seems that wait_for_inferior()
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never sees the first instruction when single stepping. When a
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signal is delivered while stepping, the next instruction that
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would've been stepped over isn't, instead a signal is delivered and
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the first instruction of the handler is stepped over instead. That
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puts us on the second instruction. (I added the test for the
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first instruction long after the fact, just in case the observed
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behavior is ever fixed.)
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PC_IN_SIGTRAMP is called from blockframe.c as well in order to set
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the frame's type (if a SIGTRAMP_FRAME). Because of our strange
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definition of in_sigtramp below, we can't rely on the frame's type
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getting set correctly from within blockframe.c. This is why we
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take pains to set it in init_extra_frame_info().
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NOTE: cagney/2002-11-10: I suspect the real problem here is that
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the get_prev_frame() only initializes the frame's type after the
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call to INIT_FRAME_INFO. get_prev_frame() should be fixed, this
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code shouldn't be working its way around a bug :-(. */
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int
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ppc_linux_in_sigtramp (CORE_ADDR pc, char *func_name)
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{
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CORE_ADDR lr;
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CORE_ADDR sp;
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CORE_ADDR tramp_sp;
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char buf[4];
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CORE_ADDR handler;
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lr = read_register (gdbarch_tdep (current_gdbarch)->ppc_lr_regnum);
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if (!ppc_linux_at_sigtramp_return_path (lr))
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return 0;
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sp = read_register (SP_REGNUM);
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if (target_read_memory (sp, buf, sizeof (buf)) != 0)
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return 0;
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tramp_sp = extract_unsigned_integer (buf, 4);
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if (target_read_memory (tramp_sp + PPC_LINUX_HANDLER_PTR_OFFSET, buf,
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sizeof (buf)) != 0)
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return 0;
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handler = extract_unsigned_integer (buf, 4);
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return (pc == handler || pc == handler + 4);
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}
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/*
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* The signal handler trampoline is on the stack and consists of exactly
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* two instructions. The easiest and most accurate way of determining
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* whether the pc is in one of these trampolines is by inspecting the
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* instructions. It'd be faster though if we could find a way to do this
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* via some simple address comparisons.
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*/
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static int
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ppc_linux_at_sigtramp_return_path (CORE_ADDR pc)
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{
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char buf[12];
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unsigned long pcinsn;
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if (target_read_memory (pc - 4, buf, sizeof (buf)) != 0)
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return 0;
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/* extract the instruction at the pc */
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pcinsn = extract_unsigned_integer (buf + 4, 4);
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return (
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(pcinsn == INSTR_LI_R0_0x7777
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&& extract_unsigned_integer (buf + 8, 4) == INSTR_SC)
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||
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(pcinsn == INSTR_SC
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&& extract_unsigned_integer (buf, 4) == INSTR_LI_R0_0x7777));
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}
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CORE_ADDR
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ppc_linux_skip_trampoline_code (CORE_ADDR pc)
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{
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char buf[4];
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struct obj_section *sect;
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struct objfile *objfile;
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unsigned long insn;
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CORE_ADDR plt_start = 0;
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CORE_ADDR symtab = 0;
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CORE_ADDR strtab = 0;
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int num_slots = -1;
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int reloc_index = -1;
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CORE_ADDR plt_table;
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CORE_ADDR reloc;
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CORE_ADDR sym;
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long symidx;
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char symname[1024];
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struct minimal_symbol *msymbol;
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/* Find the section pc is in; return if not in .plt */
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sect = find_pc_section (pc);
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if (!sect || strcmp (sect->the_bfd_section->name, ".plt") != 0)
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return 0;
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objfile = sect->objfile;
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/* Pick up the instruction at pc. It had better be of the
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form
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li r11, IDX
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where IDX is an index into the plt_table. */
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if (target_read_memory (pc, buf, 4) != 0)
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return 0;
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insn = extract_unsigned_integer (buf, 4);
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if ((insn & 0xffff0000) != 0x39600000 /* li r11, VAL */ )
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return 0;
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reloc_index = (insn << 16) >> 16;
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/* Find the objfile that pc is in and obtain the information
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necessary for finding the symbol name. */
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for (sect = objfile->sections; sect < objfile->sections_end; ++sect)
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{
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const char *secname = sect->the_bfd_section->name;
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if (strcmp (secname, ".plt") == 0)
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plt_start = sect->addr;
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else if (strcmp (secname, ".rela.plt") == 0)
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num_slots = ((int) sect->endaddr - (int) sect->addr) / 12;
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else if (strcmp (secname, ".dynsym") == 0)
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symtab = sect->addr;
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else if (strcmp (secname, ".dynstr") == 0)
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strtab = sect->addr;
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}
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/* Make sure we have all the information we need. */
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if (plt_start == 0 || num_slots == -1 || symtab == 0 || strtab == 0)
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return 0;
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/* Compute the value of the plt table */
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plt_table = plt_start + 72 + 8 * num_slots;
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/* Get address of the relocation entry (Elf32_Rela) */
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if (target_read_memory (plt_table + reloc_index, buf, 4) != 0)
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return 0;
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reloc = extract_address (buf, 4);
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sect = find_pc_section (reloc);
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if (!sect)
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return 0;
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if (strcmp (sect->the_bfd_section->name, ".text") == 0)
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return reloc;
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/* Now get the r_info field which is the relocation type and symbol
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index. */
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if (target_read_memory (reloc + 4, buf, 4) != 0)
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return 0;
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symidx = extract_unsigned_integer (buf, 4);
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/* Shift out the relocation type leaving just the symbol index */
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/* symidx = ELF32_R_SYM(symidx); */
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symidx = symidx >> 8;
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/* compute the address of the symbol */
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sym = symtab + symidx * 4;
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/* Fetch the string table index */
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if (target_read_memory (sym, buf, 4) != 0)
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return 0;
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symidx = extract_unsigned_integer (buf, 4);
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/* Fetch the string; we don't know how long it is. Is it possible
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that the following will fail because we're trying to fetch too
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much? */
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if (target_read_memory (strtab + symidx, symname, sizeof (symname)) != 0)
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return 0;
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/* This might not work right if we have multiple symbols with the
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same name; the only way to really get it right is to perform
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the same sort of lookup as the dynamic linker. */
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msymbol = lookup_minimal_symbol_text (symname, NULL, NULL);
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if (!msymbol)
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return 0;
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return SYMBOL_VALUE_ADDRESS (msymbol);
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}
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/* The rs6000 version of FRAME_SAVED_PC will almost work for us. The
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signal handler details are different, so we'll handle those here
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and call the rs6000 version to do the rest. */
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CORE_ADDR
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ppc_linux_frame_saved_pc (struct frame_info *fi)
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{
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if ((get_frame_type (fi) == SIGTRAMP_FRAME))
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{
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CORE_ADDR regs_addr =
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read_memory_integer (fi->frame + PPC_LINUX_REGS_PTR_OFFSET, 4);
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/* return the NIP in the regs array */
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return read_memory_integer (regs_addr + 4 * PPC_LINUX_PT_NIP, 4);
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}
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else if (fi->next && (get_frame_type (fi->next) == SIGTRAMP_FRAME))
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{
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CORE_ADDR regs_addr =
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read_memory_integer (fi->next->frame + PPC_LINUX_REGS_PTR_OFFSET, 4);
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/* return LNK in the regs array */
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return read_memory_integer (regs_addr + 4 * PPC_LINUX_PT_LNK, 4);
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}
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else
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return rs6000_frame_saved_pc (fi);
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}
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void
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ppc_linux_init_extra_frame_info (int fromleaf, struct frame_info *fi)
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{
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rs6000_init_extra_frame_info (fromleaf, fi);
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if (fi->next != 0)
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{
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/* We're called from get_prev_frame_info; check to see if
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this is a signal frame by looking to see if the pc points
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at trampoline code */
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if (ppc_linux_at_sigtramp_return_path (fi->pc))
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deprecated_set_frame_type (fi, SIGTRAMP_FRAME);
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else
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/* FIXME: cagney/2002-11-10: Is this double bogus? What
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happens if the frame has previously been marked as a dummy? */
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deprecated_set_frame_type (fi, NORMAL_FRAME);
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}
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}
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int
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ppc_linux_frameless_function_invocation (struct frame_info *fi)
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{
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/* We'll find the wrong thing if we let
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rs6000_frameless_function_invocation () search for a signal trampoline */
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if (ppc_linux_at_sigtramp_return_path (fi->pc))
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return 0;
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else
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return rs6000_frameless_function_invocation (fi);
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}
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void
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ppc_linux_frame_init_saved_regs (struct frame_info *fi)
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{
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if ((get_frame_type (fi) == SIGTRAMP_FRAME))
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{
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CORE_ADDR regs_addr;
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int i;
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if (fi->saved_regs)
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return;
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frame_saved_regs_zalloc (fi);
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regs_addr =
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read_memory_integer (fi->frame + PPC_LINUX_REGS_PTR_OFFSET, 4);
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fi->saved_regs[PC_REGNUM] = regs_addr + 4 * PPC_LINUX_PT_NIP;
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fi->saved_regs[gdbarch_tdep (current_gdbarch)->ppc_ps_regnum] =
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regs_addr + 4 * PPC_LINUX_PT_MSR;
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fi->saved_regs[gdbarch_tdep (current_gdbarch)->ppc_cr_regnum] =
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regs_addr + 4 * PPC_LINUX_PT_CCR;
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fi->saved_regs[gdbarch_tdep (current_gdbarch)->ppc_lr_regnum] =
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regs_addr + 4 * PPC_LINUX_PT_LNK;
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fi->saved_regs[gdbarch_tdep (current_gdbarch)->ppc_ctr_regnum] =
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regs_addr + 4 * PPC_LINUX_PT_CTR;
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fi->saved_regs[gdbarch_tdep (current_gdbarch)->ppc_xer_regnum] =
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regs_addr + 4 * PPC_LINUX_PT_XER;
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fi->saved_regs[gdbarch_tdep (current_gdbarch)->ppc_mq_regnum] =
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regs_addr + 4 * PPC_LINUX_PT_MQ;
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for (i = 0; i < 32; i++)
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fi->saved_regs[gdbarch_tdep (current_gdbarch)->ppc_gp0_regnum + i] =
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regs_addr + 4 * PPC_LINUX_PT_R0 + 4 * i;
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for (i = 0; i < 32; i++)
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fi->saved_regs[FP0_REGNUM + i] = regs_addr + 4 * PPC_LINUX_PT_FPR0 + 8 * i;
|
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}
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else
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rs6000_frame_init_saved_regs (fi);
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}
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CORE_ADDR
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ppc_linux_frame_chain (struct frame_info *thisframe)
|
|
{
|
|
/* Kernel properly constructs the frame chain for the handler */
|
|
if ((get_frame_type (thisframe) == SIGTRAMP_FRAME))
|
|
return read_memory_integer ((thisframe)->frame, 4);
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|
else
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return rs6000_frame_chain (thisframe);
|
|
}
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|
|
/* ppc_linux_memory_remove_breakpoints attempts to remove a breakpoint
|
|
in much the same fashion as memory_remove_breakpoint in mem-break.c,
|
|
but is careful not to write back the previous contents if the code
|
|
in question has changed in between inserting the breakpoint and
|
|
removing it.
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Here is the problem that we're trying to solve...
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|
Once upon a time, before introducing this function to remove
|
|
breakpoints from the inferior, setting a breakpoint on a shared
|
|
library function prior to running the program would not work
|
|
properly. In order to understand the problem, it is first
|
|
necessary to understand a little bit about dynamic linking on
|
|
this platform.
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|
|
A call to a shared library function is accomplished via a bl
|
|
(branch-and-link) instruction whose branch target is an entry
|
|
in the procedure linkage table (PLT). The PLT in the object
|
|
file is uninitialized. To gdb, prior to running the program, the
|
|
entries in the PLT are all zeros.
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|
|
Once the program starts running, the shared libraries are loaded
|
|
and the procedure linkage table is initialized, but the entries in
|
|
the table are not (necessarily) resolved. Once a function is
|
|
actually called, the code in the PLT is hit and the function is
|
|
resolved. In order to better illustrate this, an example is in
|
|
order; the following example is from the gdb testsuite.
|
|
|
|
We start the program shmain.
|
|
|
|
[kev@arroyo testsuite]$ ../gdb gdb.base/shmain
|
|
[...]
|
|
|
|
We place two breakpoints, one on shr1 and the other on main.
|
|
|
|
(gdb) b shr1
|
|
Breakpoint 1 at 0x100409d4
|
|
(gdb) b main
|
|
Breakpoint 2 at 0x100006a0: file gdb.base/shmain.c, line 44.
|
|
|
|
Examine the instruction (and the immediatly following instruction)
|
|
upon which the breakpoint was placed. Note that the PLT entry
|
|
for shr1 contains zeros.
|
|
|
|
(gdb) x/2i 0x100409d4
|
|
0x100409d4 <shr1>: .long 0x0
|
|
0x100409d8 <shr1+4>: .long 0x0
|
|
|
|
Now run 'til main.
|
|
|
|
(gdb) r
|
|
Starting program: gdb.base/shmain
|
|
Breakpoint 1 at 0xffaf790: file gdb.base/shr1.c, line 19.
|
|
|
|
Breakpoint 2, main ()
|
|
at gdb.base/shmain.c:44
|
|
44 g = 1;
|
|
|
|
Examine the PLT again. Note that the loading of the shared
|
|
library has initialized the PLT to code which loads a constant
|
|
(which I think is an index into the GOT) into r11 and then
|
|
branchs a short distance to the code which actually does the
|
|
resolving.
|
|
|
|
(gdb) x/2i 0x100409d4
|
|
0x100409d4 <shr1>: li r11,4
|
|
0x100409d8 <shr1+4>: b 0x10040984 <sg+4>
|
|
(gdb) c
|
|
Continuing.
|
|
|
|
Breakpoint 1, shr1 (x=1)
|
|
at gdb.base/shr1.c:19
|
|
19 l = 1;
|
|
|
|
Now we've hit the breakpoint at shr1. (The breakpoint was
|
|
reset from the PLT entry to the actual shr1 function after the
|
|
shared library was loaded.) Note that the PLT entry has been
|
|
resolved to contain a branch that takes us directly to shr1.
|
|
(The real one, not the PLT entry.)
|
|
|
|
(gdb) x/2i 0x100409d4
|
|
0x100409d4 <shr1>: b 0xffaf76c <shr1>
|
|
0x100409d8 <shr1+4>: b 0x10040984 <sg+4>
|
|
|
|
The thing to note here is that the PLT entry for shr1 has been
|
|
changed twice.
|
|
|
|
Now the problem should be obvious. GDB places a breakpoint (a
|
|
trap instruction) on the zero value of the PLT entry for shr1.
|
|
Later on, after the shared library had been loaded and the PLT
|
|
initialized, GDB gets a signal indicating this fact and attempts
|
|
(as it always does when it stops) to remove all the breakpoints.
|
|
|
|
The breakpoint removal was causing the former contents (a zero
|
|
word) to be written back to the now initialized PLT entry thus
|
|
destroying a portion of the initialization that had occurred only a
|
|
short time ago. When execution continued, the zero word would be
|
|
executed as an instruction an an illegal instruction trap was
|
|
generated instead. (0 is not a legal instruction.)
|
|
|
|
The fix for this problem was fairly straightforward. The function
|
|
memory_remove_breakpoint from mem-break.c was copied to this file,
|
|
modified slightly, and renamed to ppc_linux_memory_remove_breakpoint.
|
|
In tm-linux.h, MEMORY_REMOVE_BREAKPOINT is defined to call this new
|
|
function.
|
|
|
|
The differences between ppc_linux_memory_remove_breakpoint () and
|
|
memory_remove_breakpoint () are minor. All that the former does
|
|
that the latter does not is check to make sure that the breakpoint
|
|
location actually contains a breakpoint (trap instruction) prior
|
|
to attempting to write back the old contents. If it does contain
|
|
a trap instruction, we allow the old contents to be written back.
|
|
Otherwise, we silently do nothing.
|
|
|
|
The big question is whether memory_remove_breakpoint () should be
|
|
changed to have the same functionality. The downside is that more
|
|
traffic is generated for remote targets since we'll have an extra
|
|
fetch of a memory word each time a breakpoint is removed.
|
|
|
|
For the time being, we'll leave this self-modifying-code-friendly
|
|
version in ppc-linux-tdep.c, but it ought to be migrated somewhere
|
|
else in the event that some other platform has similar needs with
|
|
regard to removing breakpoints in some potentially self modifying
|
|
code. */
|
|
int
|
|
ppc_linux_memory_remove_breakpoint (CORE_ADDR addr, char *contents_cache)
|
|
{
|
|
const unsigned char *bp;
|
|
int val;
|
|
int bplen;
|
|
char old_contents[BREAKPOINT_MAX];
|
|
|
|
/* Determine appropriate breakpoint contents and size for this address. */
|
|
bp = BREAKPOINT_FROM_PC (&addr, &bplen);
|
|
if (bp == NULL)
|
|
error ("Software breakpoints not implemented for this target.");
|
|
|
|
val = target_read_memory (addr, old_contents, bplen);
|
|
|
|
/* If our breakpoint is no longer at the address, this means that the
|
|
program modified the code on us, so it is wrong to put back the
|
|
old value */
|
|
if (val == 0 && memcmp (bp, old_contents, bplen) == 0)
|
|
val = target_write_memory (addr, contents_cache, bplen);
|
|
|
|
return val;
|
|
}
|
|
|
|
/* Fetch (and possibly build) an appropriate link_map_offsets
|
|
structure for GNU/Linux PPC targets using the struct offsets
|
|
defined in link.h (but without actual reference to that file).
|
|
|
|
This makes it possible to access GNU/Linux PPC shared libraries
|
|
from a GDB that was not built on an GNU/Linux PPC host (for cross
|
|
debugging). */
|
|
|
|
struct link_map_offsets *
|
|
ppc_linux_svr4_fetch_link_map_offsets (void)
|
|
{
|
|
static struct link_map_offsets lmo;
|
|
static struct link_map_offsets *lmp = NULL;
|
|
|
|
if (lmp == NULL)
|
|
{
|
|
lmp = &lmo;
|
|
|
|
lmo.r_debug_size = 8; /* The actual size is 20 bytes, but
|
|
this is all we need. */
|
|
lmo.r_map_offset = 4;
|
|
lmo.r_map_size = 4;
|
|
|
|
lmo.link_map_size = 20; /* The actual size is 560 bytes, but
|
|
this is all we need. */
|
|
lmo.l_addr_offset = 0;
|
|
lmo.l_addr_size = 4;
|
|
|
|
lmo.l_name_offset = 4;
|
|
lmo.l_name_size = 4;
|
|
|
|
lmo.l_next_offset = 12;
|
|
lmo.l_next_size = 4;
|
|
|
|
lmo.l_prev_offset = 16;
|
|
lmo.l_prev_size = 4;
|
|
}
|
|
|
|
return lmp;
|
|
}
|
|
|
|
enum {
|
|
ELF_NGREG = 48,
|
|
ELF_NFPREG = 33,
|
|
ELF_NVRREG = 33
|
|
};
|
|
|
|
enum {
|
|
ELF_GREGSET_SIZE = (ELF_NGREG * 4),
|
|
ELF_FPREGSET_SIZE = (ELF_NFPREG * 8)
|
|
};
|
|
|
|
void
|
|
ppc_linux_supply_gregset (char *buf)
|
|
{
|
|
int regi;
|
|
struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
|
|
|
|
for (regi = 0; regi < 32; regi++)
|
|
supply_register (regi, buf + 4 * regi);
|
|
|
|
supply_register (PC_REGNUM, buf + 4 * PPC_LINUX_PT_NIP);
|
|
supply_register (tdep->ppc_lr_regnum, buf + 4 * PPC_LINUX_PT_LNK);
|
|
supply_register (tdep->ppc_cr_regnum, buf + 4 * PPC_LINUX_PT_CCR);
|
|
supply_register (tdep->ppc_xer_regnum, buf + 4 * PPC_LINUX_PT_XER);
|
|
supply_register (tdep->ppc_ctr_regnum, buf + 4 * PPC_LINUX_PT_CTR);
|
|
if (tdep->ppc_mq_regnum != -1)
|
|
supply_register (tdep->ppc_mq_regnum, buf + 4 * PPC_LINUX_PT_MQ);
|
|
supply_register (tdep->ppc_ps_regnum, buf + 4 * PPC_LINUX_PT_MSR);
|
|
}
|
|
|
|
void
|
|
ppc_linux_supply_fpregset (char *buf)
|
|
{
|
|
int regi;
|
|
struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
|
|
|
|
for (regi = 0; regi < 32; regi++)
|
|
supply_register (FP0_REGNUM + regi, buf + 8 * regi);
|
|
|
|
/* The FPSCR is stored in the low order word of the last doubleword in the
|
|
fpregset. */
|
|
supply_register (tdep->ppc_fpscr_regnum, buf + 8 * 32 + 4);
|
|
}
|
|
|
|
/*
|
|
Use a local version of this function to get the correct types for regsets.
|
|
*/
|
|
|
|
static void
|
|
fetch_core_registers (char *core_reg_sect,
|
|
unsigned core_reg_size,
|
|
int which,
|
|
CORE_ADDR reg_addr)
|
|
{
|
|
if (which == 0)
|
|
{
|
|
if (core_reg_size == ELF_GREGSET_SIZE)
|
|
ppc_linux_supply_gregset (core_reg_sect);
|
|
else
|
|
warning ("wrong size gregset struct in core file");
|
|
}
|
|
else if (which == 2)
|
|
{
|
|
if (core_reg_size == ELF_FPREGSET_SIZE)
|
|
ppc_linux_supply_fpregset (core_reg_sect);
|
|
else
|
|
warning ("wrong size fpregset struct in core file");
|
|
}
|
|
}
|
|
|
|
/* Register that we are able to handle ELF file formats using standard
|
|
procfs "regset" structures. */
|
|
|
|
static struct core_fns ppc_linux_regset_core_fns =
|
|
{
|
|
bfd_target_elf_flavour, /* core_flavour */
|
|
default_check_format, /* check_format */
|
|
default_core_sniffer, /* core_sniffer */
|
|
fetch_core_registers, /* core_read_registers */
|
|
NULL /* next */
|
|
};
|
|
|
|
static void
|
|
ppc_linux_init_abi (struct gdbarch_info info,
|
|
struct gdbarch *gdbarch)
|
|
{
|
|
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
|
|
|
|
/* Until November 2001, gcc was not complying to the SYSV ABI for
|
|
returning structures less than or equal to 8 bytes in size. It was
|
|
returning everything in memory. When this was corrected, it wasn't
|
|
fixed for native platforms. */
|
|
set_gdbarch_use_struct_convention (gdbarch,
|
|
ppc_sysv_abi_broken_use_struct_convention);
|
|
|
|
if (tdep->wordsize == 4)
|
|
{
|
|
/* Note: kevinb/2002-04-12: See note in rs6000_gdbarch_init regarding
|
|
*_push_arguments(). The same remarks hold for the methods below. */
|
|
set_gdbarch_frameless_function_invocation (gdbarch,
|
|
ppc_linux_frameless_function_invocation);
|
|
set_gdbarch_frame_chain (gdbarch, ppc_linux_frame_chain);
|
|
set_gdbarch_frame_saved_pc (gdbarch, ppc_linux_frame_saved_pc);
|
|
|
|
set_gdbarch_frame_init_saved_regs (gdbarch,
|
|
ppc_linux_frame_init_saved_regs);
|
|
set_gdbarch_init_extra_frame_info (gdbarch,
|
|
ppc_linux_init_extra_frame_info);
|
|
|
|
set_gdbarch_memory_remove_breakpoint (gdbarch,
|
|
ppc_linux_memory_remove_breakpoint);
|
|
set_solib_svr4_fetch_link_map_offsets
|
|
(gdbarch, ppc_linux_svr4_fetch_link_map_offsets);
|
|
}
|
|
}
|
|
|
|
void
|
|
_initialize_ppc_linux_tdep (void)
|
|
{
|
|
gdbarch_register_osabi (bfd_arch_powerpc, 0, GDB_OSABI_LINUX,
|
|
ppc_linux_init_abi);
|
|
add_core_fns (&ppc_linux_regset_core_fns);
|
|
}
|