2000-04-05 17:38:05 +02:00
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/* GNU/Linux on ARM target support.
|
2005-02-06 Andrew Cagney <cagney@gnu.org>
* value.c (value_contents, value_contents_writeable): New
functions.
* value.h (VALUE_CONTENTS): Delete macro.
(value_contents, value_contents_writeable): Declare.
* xstormy16-tdep.c, value.c, valops.c, valarith.c: Update.
* stack.c, sparc-tdep.c, sparc64-tdep.c, sh-tdep.c: Update.
* sh64-tdep.c, scm-valprint.c, scm-exp.c, s390-tdep.c: Update.
* rs6000-tdep.c, p-valprint.c, printcmd.c: Update.
* ppc-sysv-tdep.c, mips-tdep.c, mi/mi-main.c: Update.
* m88k-tdep.c, m68hc11-tdep.c, m32r-tdep.c: Update.
* jv-valprint.c, ia64-tdep.c, hppa-tdep.c: Update.
* hpacc-abi.c, f-valprint.c, frv-tdep.c, eval.c: Update.
* c-valprint.c, cris-tdep.c, cp-valprint.c: Update.
* cli/cli-dump.c, breakpoint.c, avr-tdep.c, arm-tdep.c: Update.
* arm-linux-tdep.c, amd64-tdep.c, alpha-tdep.c: Update.
* ada-valprint.c, ada-lang.c: Update.
2005-02-07 01:09:56 +01:00
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2006-01-15 19:28:58 +01:00
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Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006
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2005-12-22 18:06:25 +01:00
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Free Software Foundation, Inc.
|
2000-04-05 17:38:05 +02:00
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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
|
2005-12-17 23:34:03 +01:00
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Foundation, Inc., 51 Franklin Street, Fifth Floor,
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Boston, MA 02110-1301, USA. */
|
2000-04-05 17:38:05 +02:00
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#include "defs.h"
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2000-04-05 19:24:08 +02:00
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#include "target.h"
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#include "value.h"
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2000-04-05 17:38:05 +02:00
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#include "gdbtypes.h"
|
2000-04-08 00:26:11 +02:00
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#include "floatformat.h"
|
2000-09-06 02:39:11 +02:00
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#include "gdbcore.h"
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#include "frame.h"
|
2001-03-01 02:39:22 +01:00
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#include "regcache.h"
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* defs.h (HOST_FLOAT_FORMAT, HOST_DOUBLE_FORMAT)
(HOST_FLOAT_FORMAT, HOST_DOUBLE_FORMAT)
(HOST_LONG_DOUBLE_FORMAT, DOUBLEST)
(floatformat_to_doublest, floatformat_from_doublest)
(floatformat_is_negative, floatformat_is_nan)
(floatformat_mantissa, store_floating)
(extract_floating): Move declaration from here.
* doublest.h: To here. New file.
* utils.c (get_field, floatformat_to_doublest, put_field)
(ldfrexp, floatformat_from_doublest, floatformat_is_negative)
(floatformat_is_nan, floatformat_mantissa)
(FLOATFORMAT_CHAR_BIT): Move from here.
* doublest.c: To here. New file.
* findvar.c (store_floating, extract_floating): Move from here.
* doublest.c: To here.
* Makefile.in (SFILES): Add doublest.c.
(COMMON_OBS): Add doublest.o.
(doublest.o): Specify dependencies.
(doublest_h): Define.
* config/m88k/tm-m88k.h: Include "doublest.h".
* config/i960/tm-i960.h: Ditto.
* config/i386/tm-symmetry.h: Ditto.
* rs6000-tdep.c, valarith.c: Ditto.
* valprint.c, stabsread.c, sh-tdep.c: Ditto.
* ia64-tdep.c, i387-tdep.c, i386-tdep.c: Ditto.
* values.c, arm-tdep.c, arm-linux-tdep.c: Ditto.
* alpha-tdep.c, ax.h, expression.h: Ditto.
* sh-tdep.c, parse.c, top.c, value.h: Ditto.
* Makefile.in (arm-tdep.o): Add $(doublest_h).
(i386-tdep.o, i387-tdep.o, ia64-tdep.o): Ditto.
(rs6000-tdep.o, stabsread.o, valarith.o): Ditto.
(values.o, valprint.o, arm-linux-tdep.o): Ditto.
(alpha-tdep.o, ax_h, parse.o, top.o, value_h): Ditto.
(parser_defs_h): Ditto.
(expression_h): Add $(doublest_h) and $(symtab_h).
2001-08-01 20:39:27 +02:00
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#include "doublest.h"
|
2003-06-13 16:13:13 +02:00
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#include "solib-svr4.h"
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2003-01-05 00:38:46 +01:00
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#include "osabi.h"
|
2005-12-22 18:06:25 +01:00
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#include "trad-frame.h"
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#include "tramp-frame.h"
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2000-04-05 17:38:05 +02:00
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* arm-tdep.h: New file.
* arm-tdep.c: Include arm-tdep.h.
(arm_addr_bits_remove, arm_smash_text_address, arm_saved_pc_after_call)
(arm_skip_prologue, arm_call_dummy_words, arm_fix_call_dummy)
(arm_print_float_info, arm_register_type, convert_to_extended)
(arm_elf_make_msymbols_special, arm_coff_make_msymbol_special)
(arm_extract_return_value, arm_register_name): Make static.
(arm_software_single_step): Similarly. Fix types in declaration.
(arm_register_byte, arm_register_raw_size, arm_register_virtual_size)
(arm_store_return_value, arm_store_struct_return): New functions.
(arm_gdbarch_init): Register the above functions. Also register
call_dummy_start_offset, sizeof_call_dummy_words,
function_start_offset, inner_than, decr_pc_after_break, fp_regnum,
sp_regnum, pc_regnum, register_bytes, num_regs, max_register_raw_size,
max_register_virtual_size, register_size. Set up
prologue_cache.saved_regs here, rather than ...
(_initialize_arm_tdep): ... here.
* config/arm/tm-arm.h (struct type, struct value): Delete forward
declarations.
(arm_addr_bits_remove, arm_smash_text_address, arm_saved_pc_after_call)
(arm_skip_prologue, arm_call_dummy_words, arm_fix_call_dummy)
(arm_print_float_info, arm_register_type, convert_to_extended)
(arm_elf_make_msymbols_special, arm_coff_make_msymbol_special)
(arm_extract_return_value, arm_register_name): Delete declarations.
(SMASH_TEXT_ADDRESS, ADDR_BITS_REMOVE, FUNCTION_START_OFFSET)
(SKIP_PROLOGUE, SAVED_PC_AFTER_CALL, INNER_THAN, BREAKPOINT_FROM_PC)
(DECR_PC_AFTER_BREAK, PRINT_FLOAT_INFO, REGISTER_SIZE, NUM_REGS)
(REGISTER_NAME, REGISTER_BYTES, REGISTER_BYTE, REGISTER_RAW_SIZE)
(REGISTER_VIRTUAL_SIZE, MAX_REGISTER_RAW_SIZE)
(MAX_REGISTER_VIRTUAL_SIZE, REGISTER_VIRTUAL_TYPE, STORE_STRUCT_RETURN)
(EXTRACT_RETURN_VALUE, STORE_RETURN_VALUE, CALL_DUMMY_WORDS)
(SIZEOF_CALL_DUMMY_WORDS, CALL_DUMMY_START_OFFSET, FIX_CALL_DUMMY)
(SOFTWARE_SINGLE_STEP_P, SOFTWARE_SINGLE_STEP)
(ELF_MAKE_MSYMBOL_SPECIAL, COFF_MAKE_MSYMBOL_SPECIAL) Delete.
(arm_pc_is_thumb, arm_pc_is_thumb_dummy, thumb_get_next_pc)
(arm_get_next_pc): No-longer static -- these are needed by the RDI
interface.
* arm-linux-nat.c arm-linux-tdep.c armnbsd-nat.c: Include arm-tdep.h.
* remote-rdi.c remote-rdp.c: Likewise.
* Makefile.in (arm-linux-nat.o, arm-linux-tdep.o arm-tdep.o)
(armnbsd-nat.o, remote-rdi.o, remote_rdp.o): Update dependencies.
* config/arm/tm-nbsd.h (SOFTWARE_SINGLE_STEP_P): Delete bogus
definition.
* arm-tdep.h (ARM_A1_REGNUM, ARM_A4_REGNUM, ARM_AP_REGNUM)
(ARM_SP_REGNUM, ARM_LR_REGNUM, ARM_PC_REGNUM, ARM_F0_REGNUM)
(ARM_F3_REGNUM, ARM_F7_REGNUM, ARM_FPS_REGNUM, ARM_PS_REGNUM): Renamed
from non-ARM_ prefixed definitions.
* arm-tdep.c armnbsd-nat.c arm-linux-nat.c arm-linux-tdep.c: Update
all uses of above.
* remote-rdi.c remote-rdp.c: Likewise.
* arm-linux-nat.c (ARM_CPSR_REGNUM): Renamed from CPSR_REGNUM.
2002-02-11 19:34:12 +01:00
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#include "arm-tdep.h"
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2003-11-09 18:32:32 +01:00
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#include "glibc-tdep.h"
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2000-05-25 20:24:33 +02:00
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2005-12-22 18:06:25 +01:00
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#include "gdb_string.h"
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2002-02-19 15:29:00 +01:00
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/* Under ARM GNU/Linux the traditional way of performing a breakpoint
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is to execute a particular software interrupt, rather than use a
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particular undefined instruction to provoke a trap. Upon exection
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of the software interrupt the kernel stops the inferior with a
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2005-03-29 18:57:30 +02:00
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SIGTRAP, and wakes the debugger. */
|
2002-02-15 17:12:24 +01:00
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2003-09-07 03:36:00 +02:00
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static const char arm_linux_arm_le_breakpoint[] = { 0x01, 0x00, 0x9f, 0xef };
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static const char arm_linux_arm_be_breakpoint[] = { 0xef, 0x9f, 0x00, 0x01 };
|
2002-02-15 17:12:24 +01:00
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2005-11-13 19:04:14 +01:00
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/* However, the EABI syscall interface (new in Nov. 2005) does not look at
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the operand of the swi if old-ABI compatibility is disabled. Therefore,
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use an undefined instruction instead. This is supported as of kernel
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version 2.5.70 (May 2003), so should be a safe assumption for EABI
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binaries. */
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static const char eabi_linux_arm_le_breakpoint[] = { 0xf0, 0x01, 0xf0, 0xe7 };
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static const char eabi_linux_arm_be_breakpoint[] = { 0xe7, 0xf0, 0x01, 0xf0 };
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/* All the kernels which support Thumb support using a specific undefined
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instruction for the Thumb breakpoint. */
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|
2005-03-29 18:57:30 +02:00
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static const char arm_linux_thumb_be_breakpoint[] = {0xde, 0x01};
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static const char arm_linux_thumb_le_breakpoint[] = {0x01, 0xde};
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2002-02-18 14:35:31 +01:00
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/* Description of the longjmp buffer. */
|
2004-03-25 17:52:42 +01:00
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#define ARM_LINUX_JB_ELEMENT_SIZE INT_REGISTER_SIZE
|
2002-05-15 14:29:41 +02:00
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#define ARM_LINUX_JB_PC 21
|
2000-04-05 17:38:05 +02:00
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/* Extract from an array REGBUF containing the (raw) register state
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a function return value of type TYPE, and copy that, in virtual format,
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into VALBUF. */
|
2002-02-23 18:07:57 +01:00
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/* FIXME rearnsha/2002-02-23: This function shouldn't be necessary.
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The ARM generic one should be able to handle the model used by
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linux and the low-level formatting of the registers should be
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hidden behind the regcache abstraction. */
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static void
|
2000-04-05 17:38:05 +02:00
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arm_linux_extract_return_value (struct type *type,
|
2003-05-17 08:00:01 +02:00
|
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char regbuf[],
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2000-04-05 17:38:05 +02:00
|
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char *valbuf)
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{
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/* ScottB: This needs to be looked at to handle the different
|
2002-02-19 15:29:00 +01:00
|
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|
floating point emulators on ARM GNU/Linux. Right now the code
|
2000-04-05 17:38:05 +02:00
|
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|
assumes that fetch inferior registers does the right thing for
|
|
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GDB. I suspect this won't handle NWFPE registers correctly, nor
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will the default ARM version (arm_extract_return_value()). */
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* arm-tdep.h: New file.
* arm-tdep.c: Include arm-tdep.h.
(arm_addr_bits_remove, arm_smash_text_address, arm_saved_pc_after_call)
(arm_skip_prologue, arm_call_dummy_words, arm_fix_call_dummy)
(arm_print_float_info, arm_register_type, convert_to_extended)
(arm_elf_make_msymbols_special, arm_coff_make_msymbol_special)
(arm_extract_return_value, arm_register_name): Make static.
(arm_software_single_step): Similarly. Fix types in declaration.
(arm_register_byte, arm_register_raw_size, arm_register_virtual_size)
(arm_store_return_value, arm_store_struct_return): New functions.
(arm_gdbarch_init): Register the above functions. Also register
call_dummy_start_offset, sizeof_call_dummy_words,
function_start_offset, inner_than, decr_pc_after_break, fp_regnum,
sp_regnum, pc_regnum, register_bytes, num_regs, max_register_raw_size,
max_register_virtual_size, register_size. Set up
prologue_cache.saved_regs here, rather than ...
(_initialize_arm_tdep): ... here.
* config/arm/tm-arm.h (struct type, struct value): Delete forward
declarations.
(arm_addr_bits_remove, arm_smash_text_address, arm_saved_pc_after_call)
(arm_skip_prologue, arm_call_dummy_words, arm_fix_call_dummy)
(arm_print_float_info, arm_register_type, convert_to_extended)
(arm_elf_make_msymbols_special, arm_coff_make_msymbol_special)
(arm_extract_return_value, arm_register_name): Delete declarations.
(SMASH_TEXT_ADDRESS, ADDR_BITS_REMOVE, FUNCTION_START_OFFSET)
(SKIP_PROLOGUE, SAVED_PC_AFTER_CALL, INNER_THAN, BREAKPOINT_FROM_PC)
(DECR_PC_AFTER_BREAK, PRINT_FLOAT_INFO, REGISTER_SIZE, NUM_REGS)
(REGISTER_NAME, REGISTER_BYTES, REGISTER_BYTE, REGISTER_RAW_SIZE)
(REGISTER_VIRTUAL_SIZE, MAX_REGISTER_RAW_SIZE)
(MAX_REGISTER_VIRTUAL_SIZE, REGISTER_VIRTUAL_TYPE, STORE_STRUCT_RETURN)
(EXTRACT_RETURN_VALUE, STORE_RETURN_VALUE, CALL_DUMMY_WORDS)
(SIZEOF_CALL_DUMMY_WORDS, CALL_DUMMY_START_OFFSET, FIX_CALL_DUMMY)
(SOFTWARE_SINGLE_STEP_P, SOFTWARE_SINGLE_STEP)
(ELF_MAKE_MSYMBOL_SPECIAL, COFF_MAKE_MSYMBOL_SPECIAL) Delete.
(arm_pc_is_thumb, arm_pc_is_thumb_dummy, thumb_get_next_pc)
(arm_get_next_pc): No-longer static -- these are needed by the RDI
interface.
* arm-linux-nat.c arm-linux-tdep.c armnbsd-nat.c: Include arm-tdep.h.
* remote-rdi.c remote-rdp.c: Likewise.
* Makefile.in (arm-linux-nat.o, arm-linux-tdep.o arm-tdep.o)
(armnbsd-nat.o, remote-rdi.o, remote_rdp.o): Update dependencies.
* config/arm/tm-nbsd.h (SOFTWARE_SINGLE_STEP_P): Delete bogus
definition.
* arm-tdep.h (ARM_A1_REGNUM, ARM_A4_REGNUM, ARM_AP_REGNUM)
(ARM_SP_REGNUM, ARM_LR_REGNUM, ARM_PC_REGNUM, ARM_F0_REGNUM)
(ARM_F3_REGNUM, ARM_F7_REGNUM, ARM_FPS_REGNUM, ARM_PS_REGNUM): Renamed
from non-ARM_ prefixed definitions.
* arm-tdep.c armnbsd-nat.c arm-linux-nat.c arm-linux-tdep.c: Update
all uses of above.
* remote-rdi.c remote-rdp.c: Likewise.
* arm-linux-nat.c (ARM_CPSR_REGNUM): Renamed from CPSR_REGNUM.
2002-02-11 19:34:12 +01:00
|
|
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int regnum = ((TYPE_CODE_FLT == TYPE_CODE (type))
|
|
|
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? ARM_F0_REGNUM : ARM_A1_REGNUM);
|
2003-09-17 Andrew Cagney <cagney@redhat.com>
* gdbarch.sh (DEPRECATED_REGISTER_BYTE): Rename REGISTER_BYTE.
* gdbarch.h, gdbarch.c: Regenerate.
* arm-linux-tdep.c, core-sol2.c, cris-tdep.c: Update.
* d10v-tdep.c, frame.c: Update.
* hppa-tdep.c, hppab-nat.c, hppah-nat.c, hppam3-nat.c: Update.
* hpux-thread.c, i386gnu-nat.c, ia64-aix-nat.c: Update.
* ia64-linux-nat.c, irix5-nat.c, lynx-nat.c, m68knbsd-nat.c: Update.
* mcore-tdep.c, mips-linux-tdep.c, mips-tdep.c: Update.
* mipsv4-nat.c, mn10300-tdep.c, ns32k-tdep.c: Update.
* ns32knbsd-nat.c, ppc-bdm.c, regcache.c, remote-sds.c: Update.
* remote-vx68.c, remote-vxmips.c, remote-vxsparc.c: Update.
* remote.c, rs6000-tdep.c, s390-tdep.c, sh64-tdep.c: Update.
* sparc-nat.c, sparc-tdep.c, sun3-nat.c, v850-tdep.c: Update.
* v850ice.c, vax-tdep.c, xstormy16-tdep.c: Update.
* config/m68k/tm-cisco.h, config/m68k/tm-delta68.h: Update.
* config/pa/nm-hppah.h: Update.
2003-09-17 Andrew Cagney <cagney@redhat.com>
* mi/mi-main.c: Rename REGISTER_BYTE to DEPRECATED_REGISTER_BYTE.
2003-09-17 16:24:31 +02:00
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memcpy (valbuf, ®buf[DEPRECATED_REGISTER_BYTE (regnum)], TYPE_LENGTH (type));
|
2000-04-05 17:38:05 +02:00
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}
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2000-04-08 00:26:11 +02:00
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2000-04-10 23:02:33 +02:00
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|
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/*
|
2002-02-19 15:29:00 +01:00
|
|
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Dynamic Linking on ARM GNU/Linux
|
|
|
|
--------------------------------
|
2000-04-10 23:02:33 +02:00
|
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Note: PLT = procedure linkage table
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GOT = global offset table
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As much as possible, ELF dynamic linking defers the resolution of
|
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|
|
jump/call addresses until the last minute. The technique used is
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|
|
inspired by the i386 ELF design, and is based on the following
|
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|
|
constraints.
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1) The calling technique should not force a change in the assembly
|
|
|
|
code produced for apps; it MAY cause changes in the way assembly
|
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|
|
code is produced for position independent code (i.e. shared
|
|
|
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libraries).
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2) The technique must be such that all executable areas must not be
|
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modified; and any modified areas must not be executed.
|
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To do this, there are three steps involved in a typical jump:
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1) in the code
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2) through the PLT
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3) using a pointer from the GOT
|
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|
When the executable or library is first loaded, each GOT entry is
|
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initialized to point to the code which implements dynamic name
|
|
|
|
resolution and code finding. This is normally a function in the
|
2002-02-19 15:29:00 +01:00
|
|
|
program interpreter (on ARM GNU/Linux this is usually
|
|
|
|
ld-linux.so.2, but it does not have to be). On the first
|
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|
|
invocation, the function is located and the GOT entry is replaced
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|
|
with the real function address. Subsequent calls go through steps
|
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|
|
1, 2 and 3 and end up calling the real code.
|
2000-04-10 23:02:33 +02:00
|
|
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|
|
|
1) In the code:
|
|
|
|
|
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|
|
b function_call
|
|
|
|
bl function_call
|
|
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|
|
This is typical ARM code using the 26 bit relative branch or branch
|
|
|
|
and link instructions. The target of the instruction
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|
(function_call is usually the address of the function to be called.
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|
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|
In position independent code, the target of the instruction is
|
|
|
|
actually an entry in the PLT when calling functions in a shared
|
|
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|
library. Note that this call is identical to a normal function
|
|
|
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call, only the target differs.
|
|
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|
2) In the PLT:
|
|
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|
The PLT is a synthetic area, created by the linker. It exists in
|
|
|
|
both executables and libraries. It is an array of stubs, one per
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|
|
|
imported function call. It looks like this:
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PLT[0]:
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str lr, [sp, #-4]! @push the return address (lr)
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ldr lr, [pc, #16] @load from 6 words ahead
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add lr, pc, lr @form an address for GOT[0]
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ldr pc, [lr, #8]! @jump to the contents of that addr
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The return address (lr) is pushed on the stack and used for
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calculations. The load on the second line loads the lr with
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&GOT[3] - . - 20. The addition on the third leaves:
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lr = (&GOT[3] - . - 20) + (. + 8)
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lr = (&GOT[3] - 12)
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lr = &GOT[0]
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On the fourth line, the pc and lr are both updated, so that:
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pc = GOT[2]
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lr = &GOT[0] + 8
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= &GOT[2]
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NOTE: PLT[0] borrows an offset .word from PLT[1]. This is a little
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"tight", but allows us to keep all the PLT entries the same size.
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PLT[n+1]:
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ldr ip, [pc, #4] @load offset from gotoff
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add ip, pc, ip @add the offset to the pc
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ldr pc, [ip] @jump to that address
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gotoff: .word GOT[n+3] - .
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The load on the first line, gets an offset from the fourth word of
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the PLT entry. The add on the second line makes ip = &GOT[n+3],
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which contains either a pointer to PLT[0] (the fixup trampoline) or
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a pointer to the actual code.
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3) In the GOT:
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The GOT contains helper pointers for both code (PLT) fixups and
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data fixups. The first 3 entries of the GOT are special. The next
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M entries (where M is the number of entries in the PLT) belong to
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the PLT fixups. The next D (all remaining) entries belong to
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various data fixups. The actual size of the GOT is 3 + M + D.
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The GOT is also a synthetic area, created by the linker. It exists
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in both executables and libraries. When the GOT is first
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initialized , all the GOT entries relating to PLT fixups are
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pointing to code back at PLT[0].
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The special entries in the GOT are:
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GOT[0] = linked list pointer used by the dynamic loader
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GOT[1] = pointer to the reloc table for this module
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GOT[2] = pointer to the fixup/resolver code
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The first invocation of function call comes through and uses the
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fixup/resolver code. On the entry to the fixup/resolver code:
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ip = &GOT[n+3]
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lr = &GOT[2]
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stack[0] = return address (lr) of the function call
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[r0, r1, r2, r3] are still the arguments to the function call
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This is enough information for the fixup/resolver code to work
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with. Before the fixup/resolver code returns, it actually calls
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the requested function and repairs &GOT[n+3]. */
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2000-09-06 02:39:11 +02:00
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/* The constants below were determined by examining the following files
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in the linux kernel sources:
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arch/arm/kernel/signal.c
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- see SWI_SYS_SIGRETURN and SWI_SYS_RT_SIGRETURN
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include/asm-arm/unistd.h
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- see __NR_sigreturn, __NR_rt_sigreturn, and __NR_SYSCALL_BASE */
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#define ARM_LINUX_SIGRETURN_INSTR 0xef900077
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#define ARM_LINUX_RT_SIGRETURN_INSTR 0xef9000ad
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2005-12-22 18:06:25 +01:00
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/* For ARM EABI, recognize the pattern that glibc uses... alternatively,
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we could arrange to do this by function name, but they are not always
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exported. */
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#define ARM_SET_R7_SIGRETURN 0xe3a07077
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#define ARM_SET_R7_RT_SIGRETURN 0xe3a070ad
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#define ARM_EABI_SYSCALL 0xef000000
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2000-09-06 02:39:11 +02:00
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2005-12-22 18:06:25 +01:00
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static void
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arm_linux_sigtramp_cache (struct frame_info *next_frame,
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struct trad_frame_cache *this_cache,
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CORE_ADDR func, int regs_offset)
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2000-09-06 02:39:11 +02:00
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{
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2005-12-22 18:06:25 +01:00
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CORE_ADDR sp = frame_unwind_register_unsigned (next_frame, ARM_SP_REGNUM);
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CORE_ADDR base = sp + regs_offset;
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int i;
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2000-09-06 02:39:11 +02:00
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2005-12-22 18:06:25 +01:00
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for (i = 0; i < 16; i++)
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trad_frame_set_reg_addr (this_cache, i, base + i * 4);
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2000-09-06 02:39:11 +02:00
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2005-12-22 18:06:25 +01:00
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trad_frame_set_reg_addr (this_cache, ARM_PS_REGNUM, base + 16 * 4);
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2000-09-06 02:39:11 +02:00
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2005-12-22 18:06:25 +01:00
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/* The VFP or iWMMXt registers may be saved on the stack, but there's
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no reliable way to restore them (yet). */
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2000-09-06 02:39:11 +02:00
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2005-12-22 18:06:25 +01:00
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/* Save a frame ID. */
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trad_frame_set_id (this_cache, frame_id_build (sp, func));
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}
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2000-09-06 02:39:11 +02:00
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2005-12-22 18:06:25 +01:00
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static void
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arm_linux_sigreturn_init (const struct tramp_frame *self,
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struct frame_info *next_frame,
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struct trad_frame_cache *this_cache,
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CORE_ADDR func)
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2000-09-06 02:39:11 +02:00
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{
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2005-12-22 18:06:25 +01:00
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arm_linux_sigtramp_cache (next_frame, this_cache, func,
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0x0c /* Offset to registers. */);
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}
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2000-09-06 02:39:11 +02:00
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2005-12-22 18:06:25 +01:00
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static void
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arm_linux_rt_sigreturn_init (const struct tramp_frame *self,
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struct frame_info *next_frame,
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struct trad_frame_cache *this_cache,
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CORE_ADDR func)
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{
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arm_linux_sigtramp_cache (next_frame, this_cache, func,
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0x88 /* Offset to ucontext_t. */
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+ 0x14 /* Offset to sigcontext. */
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+ 0x0c /* Offset to registers. */);
|
2000-09-06 02:39:11 +02:00
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}
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|
2005-12-22 18:06:25 +01:00
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static struct tramp_frame arm_linux_sigreturn_tramp_frame = {
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SIGTRAMP_FRAME,
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4,
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{
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{ ARM_LINUX_SIGRETURN_INSTR, -1 },
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{ TRAMP_SENTINEL_INSN }
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},
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arm_linux_sigreturn_init
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|
};
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static struct tramp_frame arm_linux_rt_sigreturn_tramp_frame = {
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SIGTRAMP_FRAME,
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4,
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{
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{ ARM_LINUX_RT_SIGRETURN_INSTR, -1 },
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{ TRAMP_SENTINEL_INSN }
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},
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|
|
arm_linux_rt_sigreturn_init
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|
|
};
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|
|
static struct tramp_frame arm_eabi_linux_sigreturn_tramp_frame = {
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SIGTRAMP_FRAME,
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4,
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{
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|
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{ ARM_SET_R7_SIGRETURN, -1 },
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{ ARM_EABI_SYSCALL, -1 },
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|
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{ TRAMP_SENTINEL_INSN }
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|
|
},
|
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|
|
arm_linux_sigreturn_init
|
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|
|
};
|
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|
|
static struct tramp_frame arm_eabi_linux_rt_sigreturn_tramp_frame = {
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SIGTRAMP_FRAME,
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|
4,
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|
|
{
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|
|
{ ARM_SET_R7_RT_SIGRETURN, -1 },
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|
|
{ ARM_EABI_SYSCALL, -1 },
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|
|
{ TRAMP_SENTINEL_INSN }
|
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|
|
},
|
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|
|
arm_linux_rt_sigreturn_init
|
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|
|
};
|
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|
|
|
2002-02-15 14:35:27 +01:00
|
|
|
static void
|
|
|
|
arm_linux_init_abi (struct gdbarch_info info,
|
|
|
|
struct gdbarch *gdbarch)
|
|
|
|
{
|
|
|
|
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
|
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|
|
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|
|
tdep->lowest_pc = 0x8000;
|
2003-09-07 03:36:00 +02:00
|
|
|
if (info.byte_order == BFD_ENDIAN_BIG)
|
2005-03-29 18:57:30 +02:00
|
|
|
{
|
2005-11-13 19:04:14 +01:00
|
|
|
if (tdep->arm_abi == ARM_ABI_AAPCS)
|
|
|
|
tdep->arm_breakpoint = eabi_linux_arm_be_breakpoint;
|
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|
|
else
|
|
|
|
tdep->arm_breakpoint = arm_linux_arm_be_breakpoint;
|
2005-03-29 18:57:30 +02:00
|
|
|
tdep->thumb_breakpoint = arm_linux_thumb_be_breakpoint;
|
|
|
|
}
|
2003-09-07 03:36:00 +02:00
|
|
|
else
|
2005-03-29 18:57:30 +02:00
|
|
|
{
|
2005-11-13 19:04:14 +01:00
|
|
|
if (tdep->arm_abi == ARM_ABI_AAPCS)
|
|
|
|
tdep->arm_breakpoint = eabi_linux_arm_le_breakpoint;
|
|
|
|
else
|
|
|
|
tdep->arm_breakpoint = arm_linux_arm_le_breakpoint;
|
2005-03-29 18:57:30 +02:00
|
|
|
tdep->thumb_breakpoint = arm_linux_thumb_le_breakpoint;
|
|
|
|
}
|
2002-02-15 17:12:24 +01:00
|
|
|
tdep->arm_breakpoint_size = sizeof (arm_linux_arm_le_breakpoint);
|
2005-03-29 18:57:30 +02:00
|
|
|
tdep->thumb_breakpoint_size = sizeof (arm_linux_thumb_le_breakpoint);
|
2002-02-18 14:35:31 +01:00
|
|
|
|
2005-04-14 20:40:26 +02:00
|
|
|
if (tdep->fp_model == ARM_FLOAT_AUTO)
|
|
|
|
tdep->fp_model = ARM_FLOAT_FPA;
|
2003-03-22 21:39:21 +01:00
|
|
|
|
2002-05-15 14:29:41 +02:00
|
|
|
tdep->jb_pc = ARM_LINUX_JB_PC;
|
|
|
|
tdep->jb_elt_size = ARM_LINUX_JB_ELEMENT_SIZE;
|
2002-02-23 18:07:57 +01:00
|
|
|
|
2003-06-13 16:13:13 +02:00
|
|
|
set_solib_svr4_fetch_link_map_offsets
|
2006-01-15 19:28:58 +01:00
|
|
|
(gdbarch, svr4_ilp32_fetch_link_map_offsets);
|
2003-06-13 16:13:13 +02:00
|
|
|
|
2005-09-01 14:51:23 +02:00
|
|
|
/* The following override shouldn't be needed. */
|
2002-06-15 00:55:51 +02:00
|
|
|
set_gdbarch_deprecated_extract_return_value (gdbarch, arm_linux_extract_return_value);
|
2002-02-23 23:17:12 +01:00
|
|
|
|
|
|
|
/* Shared library handling. */
|
|
|
|
set_gdbarch_skip_trampoline_code (gdbarch, find_solib_trampoline_target);
|
2003-11-15 15:02:58 +01:00
|
|
|
set_gdbarch_skip_solib_resolver (gdbarch, glibc_skip_solib_resolver);
|
2005-03-31 21:58:26 +02:00
|
|
|
|
|
|
|
/* Enable TLS support. */
|
|
|
|
set_gdbarch_fetch_tls_load_module_address (gdbarch,
|
|
|
|
svr4_fetch_objfile_link_map);
|
2005-12-22 18:06:25 +01:00
|
|
|
|
|
|
|
tramp_frame_prepend_unwinder (gdbarch,
|
|
|
|
&arm_linux_sigreturn_tramp_frame);
|
|
|
|
tramp_frame_prepend_unwinder (gdbarch,
|
|
|
|
&arm_linux_rt_sigreturn_tramp_frame);
|
|
|
|
tramp_frame_prepend_unwinder (gdbarch,
|
|
|
|
&arm_eabi_linux_sigreturn_tramp_frame);
|
|
|
|
tramp_frame_prepend_unwinder (gdbarch,
|
|
|
|
&arm_eabi_linux_rt_sigreturn_tramp_frame);
|
2002-02-15 14:35:27 +01:00
|
|
|
}
|
|
|
|
|
2000-04-05 17:38:05 +02:00
|
|
|
void
|
|
|
|
_initialize_arm_linux_tdep (void)
|
|
|
|
{
|
2002-12-21 20:58:07 +01:00
|
|
|
gdbarch_register_osabi (bfd_arch_arm, 0, GDB_OSABI_LINUX,
|
|
|
|
arm_linux_init_abi);
|
2000-04-05 17:38:05 +02:00
|
|
|
}
|