2983 lines
86 KiB
C
2983 lines
86 KiB
C
/* Common target dependent code for GDB on ARM systems.
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Copyright (C) 1988, 1989, 1991, 1992, 1993, 1995, 1996, 1998, 1999,
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2000, 2001, 2002, 2003, 2004, 2005, 2006
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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., 51 Franklin Street, Fifth Floor,
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Boston, MA 02110-1301, USA. */
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#include <ctype.h> /* XXX for isupper () */
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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 "gdbcmd.h"
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#include "gdbcore.h"
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#include "gdb_string.h"
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#include "dis-asm.h" /* For register styles. */
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#include "regcache.h"
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#include "doublest.h"
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#include "value.h"
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#include "arch-utils.h"
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#include "osabi.h"
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#include "frame-unwind.h"
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#include "frame-base.h"
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#include "trad-frame.h"
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#include "objfiles.h"
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#include "dwarf2-frame.h"
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#include "arm-tdep.h"
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#include "gdb/sim-arm.h"
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#include "elf-bfd.h"
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#include "coff/internal.h"
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#include "elf/arm.h"
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#include "gdb_assert.h"
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static int arm_debug;
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/* Macros for setting and testing a bit in a minimal symbol that marks
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it as Thumb function. The MSB of the minimal symbol's "info" field
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is used for this purpose.
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MSYMBOL_SET_SPECIAL Actually sets the "special" bit.
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MSYMBOL_IS_SPECIAL Tests the "special" bit in a minimal symbol. */
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#define MSYMBOL_SET_SPECIAL(msym) \
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MSYMBOL_INFO (msym) = (char *) (((long) MSYMBOL_INFO (msym)) \
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| 0x80000000)
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#define MSYMBOL_IS_SPECIAL(msym) \
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(((long) MSYMBOL_INFO (msym) & 0x80000000) != 0)
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/* The list of available "set arm ..." and "show arm ..." commands. */
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static struct cmd_list_element *setarmcmdlist = NULL;
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static struct cmd_list_element *showarmcmdlist = NULL;
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/* The type of floating-point to use. Keep this in sync with enum
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arm_float_model, and the help string in _initialize_arm_tdep. */
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static const char *fp_model_strings[] =
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{
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"auto",
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"softfpa",
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"fpa",
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"softvfp",
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"vfp",
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NULL
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};
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/* A variable that can be configured by the user. */
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static enum arm_float_model arm_fp_model = ARM_FLOAT_AUTO;
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static const char *current_fp_model = "auto";
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/* The ABI to use. Keep this in sync with arm_abi_kind. */
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static const char *arm_abi_strings[] =
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{
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"auto",
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"APCS",
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"AAPCS",
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NULL
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};
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/* A variable that can be configured by the user. */
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static enum arm_abi_kind arm_abi_global = ARM_ABI_AUTO;
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static const char *arm_abi_string = "auto";
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/* Number of different reg name sets (options). */
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static int num_disassembly_options;
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/* We have more registers than the disassembler as gdb can print the value
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of special registers as well.
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The general register names are overwritten by whatever is being used by
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the disassembler at the moment. We also adjust the case of cpsr and fps. */
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/* Initial value: Register names used in ARM's ISA documentation. */
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static char * arm_register_name_strings[] =
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{"r0", "r1", "r2", "r3", /* 0 1 2 3 */
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"r4", "r5", "r6", "r7", /* 4 5 6 7 */
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"r8", "r9", "r10", "r11", /* 8 9 10 11 */
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"r12", "sp", "lr", "pc", /* 12 13 14 15 */
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"f0", "f1", "f2", "f3", /* 16 17 18 19 */
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"f4", "f5", "f6", "f7", /* 20 21 22 23 */
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"fps", "cpsr" }; /* 24 25 */
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static char **arm_register_names = arm_register_name_strings;
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/* Valid register name styles. */
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static const char **valid_disassembly_styles;
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/* Disassembly style to use. Default to "std" register names. */
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static const char *disassembly_style;
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/* Index to that option in the opcodes table. */
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static int current_option;
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/* This is used to keep the bfd arch_info in sync with the disassembly
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style. */
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static void set_disassembly_style_sfunc(char *, int,
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struct cmd_list_element *);
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static void set_disassembly_style (void);
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static void convert_from_extended (const struct floatformat *, const void *,
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void *);
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static void convert_to_extended (const struct floatformat *, void *,
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const void *);
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struct arm_prologue_cache
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{
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/* The stack pointer at the time this frame was created; i.e. the
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caller's stack pointer when this function was called. It is used
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to identify this frame. */
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CORE_ADDR prev_sp;
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/* The frame base for this frame is just prev_sp + frame offset -
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frame size. FRAMESIZE is the size of this stack frame, and
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FRAMEOFFSET if the initial offset from the stack pointer (this
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frame's stack pointer, not PREV_SP) to the frame base. */
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int framesize;
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int frameoffset;
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/* The register used to hold the frame pointer for this frame. */
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int framereg;
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/* Saved register offsets. */
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struct trad_frame_saved_reg *saved_regs;
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};
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/* Addresses for calling Thumb functions have the bit 0 set.
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Here are some macros to test, set, or clear bit 0 of addresses. */
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#define IS_THUMB_ADDR(addr) ((addr) & 1)
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#define MAKE_THUMB_ADDR(addr) ((addr) | 1)
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#define UNMAKE_THUMB_ADDR(addr) ((addr) & ~1)
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/* Set to true if the 32-bit mode is in use. */
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int arm_apcs_32 = 1;
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/* Determine if the program counter specified in MEMADDR is in a Thumb
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function. */
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int
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arm_pc_is_thumb (CORE_ADDR memaddr)
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{
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struct minimal_symbol *sym;
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/* If bit 0 of the address is set, assume this is a Thumb address. */
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if (IS_THUMB_ADDR (memaddr))
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return 1;
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/* Thumb functions have a "special" bit set in minimal symbols. */
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sym = lookup_minimal_symbol_by_pc (memaddr);
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if (sym)
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{
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return (MSYMBOL_IS_SPECIAL (sym));
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}
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else
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{
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return 0;
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}
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}
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/* Remove useless bits from addresses in a running program. */
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static CORE_ADDR
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arm_addr_bits_remove (CORE_ADDR val)
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{
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if (arm_apcs_32)
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return (val & (arm_pc_is_thumb (val) ? 0xfffffffe : 0xfffffffc));
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else
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return (val & 0x03fffffc);
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}
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/* When reading symbols, we need to zap the low bit of the address,
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which may be set to 1 for Thumb functions. */
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static CORE_ADDR
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arm_smash_text_address (CORE_ADDR val)
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{
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return val & ~1;
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}
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/* Immediately after a function call, return the saved pc. Can't
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always go through the frames for this because on some machines the
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new frame is not set up until the new function executes some
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instructions. */
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static CORE_ADDR
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arm_saved_pc_after_call (struct frame_info *frame)
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{
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return ADDR_BITS_REMOVE (read_register (ARM_LR_REGNUM));
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}
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/* A typical Thumb prologue looks like this:
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push {r7, lr}
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add sp, sp, #-28
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add r7, sp, #12
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Sometimes the latter instruction may be replaced by:
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mov r7, sp
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or like this:
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push {r7, lr}
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mov r7, sp
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sub sp, #12
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or, on tpcs, like this:
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sub sp,#16
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push {r7, lr}
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(many instructions)
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mov r7, sp
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sub sp, #12
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There is always one instruction of three classes:
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1 - push
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2 - setting of r7
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3 - adjusting of sp
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When we have found at least one of each class we are done with the prolog.
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Note that the "sub sp, #NN" before the push does not count.
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*/
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static CORE_ADDR
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thumb_skip_prologue (CORE_ADDR pc, CORE_ADDR func_end)
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{
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CORE_ADDR current_pc;
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/* findmask:
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bit 0 - push { rlist }
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bit 1 - mov r7, sp OR add r7, sp, #imm (setting of r7)
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bit 2 - sub sp, #simm OR add sp, #simm (adjusting of sp)
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*/
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int findmask = 0;
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for (current_pc = pc;
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current_pc + 2 < func_end && current_pc < pc + 40;
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current_pc += 2)
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{
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unsigned short insn = read_memory_unsigned_integer (current_pc, 2);
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if ((insn & 0xfe00) == 0xb400) /* push { rlist } */
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{
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findmask |= 1; /* push found */
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}
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else if ((insn & 0xff00) == 0xb000) /* add sp, #simm OR
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sub sp, #simm */
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{
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if ((findmask & 1) == 0) /* before push ? */
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continue;
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else
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findmask |= 4; /* add/sub sp found */
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}
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else if ((insn & 0xff00) == 0xaf00) /* add r7, sp, #imm */
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{
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findmask |= 2; /* setting of r7 found */
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}
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else if (insn == 0x466f) /* mov r7, sp */
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{
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findmask |= 2; /* setting of r7 found */
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}
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else if (findmask == (4+2+1))
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{
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/* We have found one of each type of prologue instruction */
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break;
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}
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else
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/* Something in the prolog that we don't care about or some
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instruction from outside the prolog scheduled here for
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optimization. */
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continue;
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}
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return current_pc;
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}
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/* Advance the PC across any function entry prologue instructions to
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reach some "real" code.
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The APCS (ARM Procedure Call Standard) defines the following
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prologue:
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mov ip, sp
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[stmfd sp!, {a1,a2,a3,a4}]
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stmfd sp!, {...,fp,ip,lr,pc}
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[stfe f7, [sp, #-12]!]
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[stfe f6, [sp, #-12]!]
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[stfe f5, [sp, #-12]!]
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[stfe f4, [sp, #-12]!]
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sub fp, ip, #nn @@ nn == 20 or 4 depending on second insn */
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static CORE_ADDR
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arm_skip_prologue (CORE_ADDR pc)
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{
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unsigned long inst;
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CORE_ADDR skip_pc;
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CORE_ADDR func_addr, func_end = 0;
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char *func_name;
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struct symtab_and_line sal;
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/* If we're in a dummy frame, don't even try to skip the prologue. */
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if (deprecated_pc_in_call_dummy (pc))
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return pc;
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/* See what the symbol table says. */
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if (find_pc_partial_function (pc, &func_name, &func_addr, &func_end))
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{
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struct symbol *sym;
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/* Found a function. */
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sym = lookup_symbol (func_name, NULL, VAR_DOMAIN, NULL, NULL);
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if (sym && SYMBOL_LANGUAGE (sym) != language_asm)
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{
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/* Don't use this trick for assembly source files. */
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sal = find_pc_line (func_addr, 0);
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if ((sal.line != 0) && (sal.end < func_end))
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return sal.end;
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}
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}
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/* Check if this is Thumb code. */
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if (arm_pc_is_thumb (pc))
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return thumb_skip_prologue (pc, func_end);
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/* Can't find the prologue end in the symbol table, try it the hard way
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by disassembling the instructions. */
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/* Like arm_scan_prologue, stop no later than pc + 64. */
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if (func_end == 0 || func_end > pc + 64)
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func_end = pc + 64;
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for (skip_pc = pc; skip_pc < func_end; skip_pc += 4)
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{
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inst = read_memory_unsigned_integer (skip_pc, 4);
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/* "mov ip, sp" is no longer a required part of the prologue. */
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if (inst == 0xe1a0c00d) /* mov ip, sp */
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continue;
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if ((inst & 0xfffff000) == 0xe28dc000) /* add ip, sp #n */
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continue;
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if ((inst & 0xfffff000) == 0xe24dc000) /* sub ip, sp #n */
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continue;
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/* Some prologues begin with "str lr, [sp, #-4]!". */
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if (inst == 0xe52de004) /* str lr, [sp, #-4]! */
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continue;
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if ((inst & 0xfffffff0) == 0xe92d0000) /* stmfd sp!,{a1,a2,a3,a4} */
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continue;
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if ((inst & 0xfffff800) == 0xe92dd800) /* stmfd sp!,{fp,ip,lr,pc} */
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continue;
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/* Any insns after this point may float into the code, if it makes
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for better instruction scheduling, so we skip them only if we
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find them, but still consider the function to be frame-ful. */
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/* We may have either one sfmfd instruction here, or several stfe
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insns, depending on the version of floating point code we
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support. */
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if ((inst & 0xffbf0fff) == 0xec2d0200) /* sfmfd fn, <cnt>, [sp]! */
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continue;
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if ((inst & 0xffff8fff) == 0xed6d0103) /* stfe fn, [sp, #-12]! */
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continue;
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if ((inst & 0xfffff000) == 0xe24cb000) /* sub fp, ip, #nn */
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continue;
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if ((inst & 0xfffff000) == 0xe24dd000) /* sub sp, sp, #nn */
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continue;
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if ((inst & 0xffffc000) == 0xe54b0000 || /* strb r(0123),[r11,#-nn] */
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(inst & 0xffffc0f0) == 0xe14b00b0 || /* strh r(0123),[r11,#-nn] */
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(inst & 0xffffc000) == 0xe50b0000) /* str r(0123),[r11,#-nn] */
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continue;
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if ((inst & 0xffffc000) == 0xe5cd0000 || /* strb r(0123),[sp,#nn] */
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(inst & 0xffffc0f0) == 0xe1cd00b0 || /* strh r(0123),[sp,#nn] */
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(inst & 0xffffc000) == 0xe58d0000) /* str r(0123),[sp,#nn] */
|
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continue;
|
||
|
||
/* Un-recognized instruction; stop scanning. */
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break;
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}
|
||
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return skip_pc; /* End of prologue */
|
||
}
|
||
|
||
/* *INDENT-OFF* */
|
||
/* Function: thumb_scan_prologue (helper function for arm_scan_prologue)
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||
This function decodes a Thumb function prologue to determine:
|
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1) the size of the stack frame
|
||
2) which registers are saved on it
|
||
3) the offsets of saved regs
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||
4) the offset from the stack pointer to the frame pointer
|
||
|
||
A typical Thumb function prologue would create this stack frame
|
||
(offsets relative to FP)
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||
old SP -> 24 stack parameters
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||
20 LR
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||
16 R7
|
||
R7 -> 0 local variables (16 bytes)
|
||
SP -> -12 additional stack space (12 bytes)
|
||
The frame size would thus be 36 bytes, and the frame offset would be
|
||
12 bytes. The frame register is R7.
|
||
|
||
The comments for thumb_skip_prolog() describe the algorithm we use
|
||
to detect the end of the prolog. */
|
||
/* *INDENT-ON* */
|
||
|
||
static void
|
||
thumb_scan_prologue (CORE_ADDR prev_pc, struct arm_prologue_cache *cache)
|
||
{
|
||
CORE_ADDR prologue_start;
|
||
CORE_ADDR prologue_end;
|
||
CORE_ADDR current_pc;
|
||
/* Which register has been copied to register n? */
|
||
int saved_reg[16];
|
||
/* findmask:
|
||
bit 0 - push { rlist }
|
||
bit 1 - mov r7, sp OR add r7, sp, #imm (setting of r7)
|
||
bit 2 - sub sp, #simm OR add sp, #simm (adjusting of sp)
|
||
*/
|
||
int findmask = 0;
|
||
int i;
|
||
|
||
if (find_pc_partial_function (prev_pc, NULL, &prologue_start, &prologue_end))
|
||
{
|
||
struct symtab_and_line sal = find_pc_line (prologue_start, 0);
|
||
|
||
if (sal.line == 0) /* no line info, use current PC */
|
||
prologue_end = prev_pc;
|
||
else if (sal.end < prologue_end) /* next line begins after fn end */
|
||
prologue_end = sal.end; /* (probably means no prologue) */
|
||
}
|
||
else
|
||
/* We're in the boondocks: we have no idea where the start of the
|
||
function is. */
|
||
return;
|
||
|
||
prologue_end = min (prologue_end, prev_pc);
|
||
|
||
/* Initialize the saved register map. When register H is copied to
|
||
register L, we will put H in saved_reg[L]. */
|
||
for (i = 0; i < 16; i++)
|
||
saved_reg[i] = i;
|
||
|
||
/* Search the prologue looking for instructions that set up the
|
||
frame pointer, adjust the stack pointer, and save registers.
|
||
Do this until all basic prolog instructions are found. */
|
||
|
||
cache->framesize = 0;
|
||
for (current_pc = prologue_start;
|
||
(current_pc < prologue_end) && ((findmask & 7) != 7);
|
||
current_pc += 2)
|
||
{
|
||
unsigned short insn;
|
||
int regno;
|
||
int offset;
|
||
|
||
insn = read_memory_unsigned_integer (current_pc, 2);
|
||
|
||
if ((insn & 0xfe00) == 0xb400) /* push { rlist } */
|
||
{
|
||
int mask;
|
||
findmask |= 1; /* push found */
|
||
/* Bits 0-7 contain a mask for registers R0-R7. Bit 8 says
|
||
whether to save LR (R14). */
|
||
mask = (insn & 0xff) | ((insn & 0x100) << 6);
|
||
|
||
/* Calculate offsets of saved R0-R7 and LR. */
|
||
for (regno = ARM_LR_REGNUM; regno >= 0; regno--)
|
||
if (mask & (1 << regno))
|
||
{
|
||
cache->framesize += 4;
|
||
cache->saved_regs[saved_reg[regno]].addr = -cache->framesize;
|
||
/* Reset saved register map. */
|
||
saved_reg[regno] = regno;
|
||
}
|
||
}
|
||
else if ((insn & 0xff00) == 0xb000) /* add sp, #simm OR
|
||
sub sp, #simm */
|
||
{
|
||
if ((findmask & 1) == 0) /* before push? */
|
||
continue;
|
||
else
|
||
findmask |= 4; /* add/sub sp found */
|
||
|
||
offset = (insn & 0x7f) << 2; /* get scaled offset */
|
||
if (insn & 0x80) /* is it signed? (==subtracting) */
|
||
{
|
||
cache->frameoffset += offset;
|
||
offset = -offset;
|
||
}
|
||
cache->framesize -= offset;
|
||
}
|
||
else if ((insn & 0xff00) == 0xaf00) /* add r7, sp, #imm */
|
||
{
|
||
findmask |= 2; /* setting of r7 found */
|
||
cache->framereg = THUMB_FP_REGNUM;
|
||
/* get scaled offset */
|
||
cache->frameoffset = (insn & 0xff) << 2;
|
||
}
|
||
else if (insn == 0x466f) /* mov r7, sp */
|
||
{
|
||
findmask |= 2; /* setting of r7 found */
|
||
cache->framereg = THUMB_FP_REGNUM;
|
||
cache->frameoffset = 0;
|
||
saved_reg[THUMB_FP_REGNUM] = ARM_SP_REGNUM;
|
||
}
|
||
else if ((insn & 0xffc0) == 0x4640) /* mov r0-r7, r8-r15 */
|
||
{
|
||
int lo_reg = insn & 7; /* dest. register (r0-r7) */
|
||
int hi_reg = ((insn >> 3) & 7) + 8; /* source register (r8-15) */
|
||
saved_reg[lo_reg] = hi_reg; /* remember hi reg was saved */
|
||
}
|
||
else
|
||
/* Something in the prolog that we don't care about or some
|
||
instruction from outside the prolog scheduled here for
|
||
optimization. */
|
||
continue;
|
||
}
|
||
}
|
||
|
||
/* This function decodes an ARM function prologue to determine:
|
||
1) the size of the stack frame
|
||
2) which registers are saved on it
|
||
3) the offsets of saved regs
|
||
4) the offset from the stack pointer to the frame pointer
|
||
This information is stored in the "extra" fields of the frame_info.
|
||
|
||
There are two basic forms for the ARM prologue. The fixed argument
|
||
function call will look like:
|
||
|
||
mov ip, sp
|
||
stmfd sp!, {fp, ip, lr, pc}
|
||
sub fp, ip, #4
|
||
[sub sp, sp, #4]
|
||
|
||
Which would create this stack frame (offsets relative to FP):
|
||
IP -> 4 (caller's stack)
|
||
FP -> 0 PC (points to address of stmfd instruction + 8 in callee)
|
||
-4 LR (return address in caller)
|
||
-8 IP (copy of caller's SP)
|
||
-12 FP (caller's FP)
|
||
SP -> -28 Local variables
|
||
|
||
The frame size would thus be 32 bytes, and the frame offset would be
|
||
28 bytes. The stmfd call can also save any of the vN registers it
|
||
plans to use, which increases the frame size accordingly.
|
||
|
||
Note: The stored PC is 8 off of the STMFD instruction that stored it
|
||
because the ARM Store instructions always store PC + 8 when you read
|
||
the PC register.
|
||
|
||
A variable argument function call will look like:
|
||
|
||
mov ip, sp
|
||
stmfd sp!, {a1, a2, a3, a4}
|
||
stmfd sp!, {fp, ip, lr, pc}
|
||
sub fp, ip, #20
|
||
|
||
Which would create this stack frame (offsets relative to FP):
|
||
IP -> 20 (caller's stack)
|
||
16 A4
|
||
12 A3
|
||
8 A2
|
||
4 A1
|
||
FP -> 0 PC (points to address of stmfd instruction + 8 in callee)
|
||
-4 LR (return address in caller)
|
||
-8 IP (copy of caller's SP)
|
||
-12 FP (caller's FP)
|
||
SP -> -28 Local variables
|
||
|
||
The frame size would thus be 48 bytes, and the frame offset would be
|
||
28 bytes.
|
||
|
||
There is another potential complication, which is that the optimizer
|
||
will try to separate the store of fp in the "stmfd" instruction from
|
||
the "sub fp, ip, #NN" instruction. Almost anything can be there, so
|
||
we just key on the stmfd, and then scan for the "sub fp, ip, #NN"...
|
||
|
||
Also, note, the original version of the ARM toolchain claimed that there
|
||
should be an
|
||
|
||
instruction at the end of the prologue. I have never seen GCC produce
|
||
this, and the ARM docs don't mention it. We still test for it below in
|
||
case it happens...
|
||
|
||
*/
|
||
|
||
static void
|
||
arm_scan_prologue (struct frame_info *next_frame, struct arm_prologue_cache *cache)
|
||
{
|
||
int regno, sp_offset, fp_offset, ip_offset;
|
||
CORE_ADDR prologue_start, prologue_end, current_pc;
|
||
CORE_ADDR prev_pc = frame_pc_unwind (next_frame);
|
||
|
||
/* Assume there is no frame until proven otherwise. */
|
||
cache->framereg = ARM_SP_REGNUM;
|
||
cache->framesize = 0;
|
||
cache->frameoffset = 0;
|
||
|
||
/* Check for Thumb prologue. */
|
||
if (arm_pc_is_thumb (prev_pc))
|
||
{
|
||
thumb_scan_prologue (prev_pc, cache);
|
||
return;
|
||
}
|
||
|
||
/* Find the function prologue. If we can't find the function in
|
||
the symbol table, peek in the stack frame to find the PC. */
|
||
if (find_pc_partial_function (prev_pc, NULL, &prologue_start, &prologue_end))
|
||
{
|
||
/* One way to find the end of the prologue (which works well
|
||
for unoptimized code) is to do the following:
|
||
|
||
struct symtab_and_line sal = find_pc_line (prologue_start, 0);
|
||
|
||
if (sal.line == 0)
|
||
prologue_end = prev_pc;
|
||
else if (sal.end < prologue_end)
|
||
prologue_end = sal.end;
|
||
|
||
This mechanism is very accurate so long as the optimizer
|
||
doesn't move any instructions from the function body into the
|
||
prologue. If this happens, sal.end will be the last
|
||
instruction in the first hunk of prologue code just before
|
||
the first instruction that the scheduler has moved from
|
||
the body to the prologue.
|
||
|
||
In order to make sure that we scan all of the prologue
|
||
instructions, we use a slightly less accurate mechanism which
|
||
may scan more than necessary. To help compensate for this
|
||
lack of accuracy, the prologue scanning loop below contains
|
||
several clauses which'll cause the loop to terminate early if
|
||
an implausible prologue instruction is encountered.
|
||
|
||
The expression
|
||
|
||
prologue_start + 64
|
||
|
||
is a suitable endpoint since it accounts for the largest
|
||
possible prologue plus up to five instructions inserted by
|
||
the scheduler. */
|
||
|
||
if (prologue_end > prologue_start + 64)
|
||
{
|
||
prologue_end = prologue_start + 64; /* See above. */
|
||
}
|
||
}
|
||
else
|
||
{
|
||
/* We have no symbol information. Our only option is to assume this
|
||
function has a standard stack frame and the normal frame register.
|
||
Then, we can find the value of our frame pointer on entrance to
|
||
the callee (or at the present moment if this is the innermost frame).
|
||
The value stored there should be the address of the stmfd + 8. */
|
||
CORE_ADDR frame_loc;
|
||
LONGEST return_value;
|
||
|
||
frame_loc = frame_unwind_register_unsigned (next_frame, ARM_FP_REGNUM);
|
||
if (!safe_read_memory_integer (frame_loc, 4, &return_value))
|
||
return;
|
||
else
|
||
{
|
||
prologue_start = ADDR_BITS_REMOVE (return_value) - 8;
|
||
prologue_end = prologue_start + 64; /* See above. */
|
||
}
|
||
}
|
||
|
||
if (prev_pc < prologue_end)
|
||
prologue_end = prev_pc;
|
||
|
||
/* Now search the prologue looking for instructions that set up the
|
||
frame pointer, adjust the stack pointer, and save registers.
|
||
|
||
Be careful, however, and if it doesn't look like a prologue,
|
||
don't try to scan it. If, for instance, a frameless function
|
||
begins with stmfd sp!, then we will tell ourselves there is
|
||
a frame, which will confuse stack traceback, as well as "finish"
|
||
and other operations that rely on a knowledge of the stack
|
||
traceback.
|
||
|
||
In the APCS, the prologue should start with "mov ip, sp" so
|
||
if we don't see this as the first insn, we will stop.
|
||
|
||
[Note: This doesn't seem to be true any longer, so it's now an
|
||
optional part of the prologue. - Kevin Buettner, 2001-11-20]
|
||
|
||
[Note further: The "mov ip,sp" only seems to be missing in
|
||
frameless functions at optimization level "-O2" or above,
|
||
in which case it is often (but not always) replaced by
|
||
"str lr, [sp, #-4]!". - Michael Snyder, 2002-04-23] */
|
||
|
||
sp_offset = fp_offset = ip_offset = 0;
|
||
|
||
for (current_pc = prologue_start;
|
||
current_pc < prologue_end;
|
||
current_pc += 4)
|
||
{
|
||
unsigned int insn = read_memory_unsigned_integer (current_pc, 4);
|
||
|
||
if (insn == 0xe1a0c00d) /* mov ip, sp */
|
||
{
|
||
ip_offset = 0;
|
||
continue;
|
||
}
|
||
else if ((insn & 0xfffff000) == 0xe28dc000) /* add ip, sp #n */
|
||
{
|
||
unsigned imm = insn & 0xff; /* immediate value */
|
||
unsigned rot = (insn & 0xf00) >> 7; /* rotate amount */
|
||
imm = (imm >> rot) | (imm << (32 - rot));
|
||
ip_offset = imm;
|
||
continue;
|
||
}
|
||
else if ((insn & 0xfffff000) == 0xe24dc000) /* sub ip, sp #n */
|
||
{
|
||
unsigned imm = insn & 0xff; /* immediate value */
|
||
unsigned rot = (insn & 0xf00) >> 7; /* rotate amount */
|
||
imm = (imm >> rot) | (imm << (32 - rot));
|
||
ip_offset = -imm;
|
||
continue;
|
||
}
|
||
else if (insn == 0xe52de004) /* str lr, [sp, #-4]! */
|
||
{
|
||
sp_offset -= 4;
|
||
cache->saved_regs[ARM_LR_REGNUM].addr = sp_offset;
|
||
continue;
|
||
}
|
||
else if ((insn & 0xffff0000) == 0xe92d0000)
|
||
/* stmfd sp!, {..., fp, ip, lr, pc}
|
||
or
|
||
stmfd sp!, {a1, a2, a3, a4} */
|
||
{
|
||
int mask = insn & 0xffff;
|
||
|
||
/* Calculate offsets of saved registers. */
|
||
for (regno = ARM_PC_REGNUM; regno >= 0; regno--)
|
||
if (mask & (1 << regno))
|
||
{
|
||
sp_offset -= 4;
|
||
cache->saved_regs[regno].addr = sp_offset;
|
||
}
|
||
}
|
||
else if ((insn & 0xffffc000) == 0xe54b0000 || /* strb rx,[r11,#-n] */
|
||
(insn & 0xffffc0f0) == 0xe14b00b0 || /* strh rx,[r11,#-n] */
|
||
(insn & 0xffffc000) == 0xe50b0000) /* str rx,[r11,#-n] */
|
||
{
|
||
/* No need to add this to saved_regs -- it's just an arg reg. */
|
||
continue;
|
||
}
|
||
else if ((insn & 0xffffc000) == 0xe5cd0000 || /* strb rx,[sp,#n] */
|
||
(insn & 0xffffc0f0) == 0xe1cd00b0 || /* strh rx,[sp,#n] */
|
||
(insn & 0xffffc000) == 0xe58d0000) /* str rx,[sp,#n] */
|
||
{
|
||
/* No need to add this to saved_regs -- it's just an arg reg. */
|
||
continue;
|
||
}
|
||
else if ((insn & 0xfffff000) == 0xe24cb000) /* sub fp, ip #n */
|
||
{
|
||
unsigned imm = insn & 0xff; /* immediate value */
|
||
unsigned rot = (insn & 0xf00) >> 7; /* rotate amount */
|
||
imm = (imm >> rot) | (imm << (32 - rot));
|
||
fp_offset = -imm + ip_offset;
|
||
cache->framereg = ARM_FP_REGNUM;
|
||
}
|
||
else if ((insn & 0xfffff000) == 0xe24dd000) /* sub sp, sp #n */
|
||
{
|
||
unsigned imm = insn & 0xff; /* immediate value */
|
||
unsigned rot = (insn & 0xf00) >> 7; /* rotate amount */
|
||
imm = (imm >> rot) | (imm << (32 - rot));
|
||
sp_offset -= imm;
|
||
}
|
||
else if ((insn & 0xffff7fff) == 0xed6d0103) /* stfe f?, [sp, -#c]! */
|
||
{
|
||
sp_offset -= 12;
|
||
regno = ARM_F0_REGNUM + ((insn >> 12) & 0x07);
|
||
cache->saved_regs[regno].addr = sp_offset;
|
||
}
|
||
else if ((insn & 0xffbf0fff) == 0xec2d0200) /* sfmfd f0, 4, [sp!] */
|
||
{
|
||
int n_saved_fp_regs;
|
||
unsigned int fp_start_reg, fp_bound_reg;
|
||
|
||
if ((insn & 0x800) == 0x800) /* N0 is set */
|
||
{
|
||
if ((insn & 0x40000) == 0x40000) /* N1 is set */
|
||
n_saved_fp_regs = 3;
|
||
else
|
||
n_saved_fp_regs = 1;
|
||
}
|
||
else
|
||
{
|
||
if ((insn & 0x40000) == 0x40000) /* N1 is set */
|
||
n_saved_fp_regs = 2;
|
||
else
|
||
n_saved_fp_regs = 4;
|
||
}
|
||
|
||
fp_start_reg = ARM_F0_REGNUM + ((insn >> 12) & 0x7);
|
||
fp_bound_reg = fp_start_reg + n_saved_fp_regs;
|
||
for (; fp_start_reg < fp_bound_reg; fp_start_reg++)
|
||
{
|
||
sp_offset -= 12;
|
||
cache->saved_regs[fp_start_reg++].addr = sp_offset;
|
||
}
|
||
}
|
||
else if ((insn & 0xf0000000) != 0xe0000000)
|
||
break; /* Condition not true, exit early */
|
||
else if ((insn & 0xfe200000) == 0xe8200000) /* ldm? */
|
||
break; /* Don't scan past a block load */
|
||
else
|
||
/* The optimizer might shove anything into the prologue,
|
||
so we just skip what we don't recognize. */
|
||
continue;
|
||
}
|
||
|
||
/* The frame size is just the negative of the offset (from the
|
||
original SP) of the last thing thing we pushed on the stack.
|
||
The frame offset is [new FP] - [new SP]. */
|
||
cache->framesize = -sp_offset;
|
||
if (cache->framereg == ARM_FP_REGNUM)
|
||
cache->frameoffset = fp_offset - sp_offset;
|
||
else
|
||
cache->frameoffset = 0;
|
||
}
|
||
|
||
static struct arm_prologue_cache *
|
||
arm_make_prologue_cache (struct frame_info *next_frame)
|
||
{
|
||
int reg;
|
||
struct arm_prologue_cache *cache;
|
||
CORE_ADDR unwound_fp;
|
||
|
||
cache = frame_obstack_zalloc (sizeof (struct arm_prologue_cache));
|
||
cache->saved_regs = trad_frame_alloc_saved_regs (next_frame);
|
||
|
||
arm_scan_prologue (next_frame, cache);
|
||
|
||
unwound_fp = frame_unwind_register_unsigned (next_frame, cache->framereg);
|
||
if (unwound_fp == 0)
|
||
return cache;
|
||
|
||
cache->prev_sp = unwound_fp + cache->framesize - cache->frameoffset;
|
||
|
||
/* Calculate actual addresses of saved registers using offsets
|
||
determined by arm_scan_prologue. */
|
||
for (reg = 0; reg < NUM_REGS; reg++)
|
||
if (trad_frame_addr_p (cache->saved_regs, reg))
|
||
cache->saved_regs[reg].addr += cache->prev_sp;
|
||
|
||
return cache;
|
||
}
|
||
|
||
/* Our frame ID for a normal frame is the current function's starting PC
|
||
and the caller's SP when we were called. */
|
||
|
||
static void
|
||
arm_prologue_this_id (struct frame_info *next_frame,
|
||
void **this_cache,
|
||
struct frame_id *this_id)
|
||
{
|
||
struct arm_prologue_cache *cache;
|
||
struct frame_id id;
|
||
CORE_ADDR func;
|
||
|
||
if (*this_cache == NULL)
|
||
*this_cache = arm_make_prologue_cache (next_frame);
|
||
cache = *this_cache;
|
||
|
||
func = frame_func_unwind (next_frame);
|
||
|
||
/* This is meant to halt the backtrace at "_start". Make sure we
|
||
don't halt it at a generic dummy frame. */
|
||
if (func <= LOWEST_PC)
|
||
return;
|
||
|
||
/* If we've hit a wall, stop. */
|
||
if (cache->prev_sp == 0)
|
||
return;
|
||
|
||
id = frame_id_build (cache->prev_sp, func);
|
||
*this_id = id;
|
||
}
|
||
|
||
static void
|
||
arm_prologue_prev_register (struct frame_info *next_frame,
|
||
void **this_cache,
|
||
int prev_regnum,
|
||
int *optimized,
|
||
enum lval_type *lvalp,
|
||
CORE_ADDR *addrp,
|
||
int *realnump,
|
||
gdb_byte *valuep)
|
||
{
|
||
struct arm_prologue_cache *cache;
|
||
|
||
if (*this_cache == NULL)
|
||
*this_cache = arm_make_prologue_cache (next_frame);
|
||
cache = *this_cache;
|
||
|
||
/* If we are asked to unwind the PC, then we need to return the LR
|
||
instead. The saved value of PC points into this frame's
|
||
prologue, not the next frame's resume location. */
|
||
if (prev_regnum == ARM_PC_REGNUM)
|
||
prev_regnum = ARM_LR_REGNUM;
|
||
|
||
/* SP is generally not saved to the stack, but this frame is
|
||
identified by NEXT_FRAME's stack pointer at the time of the call.
|
||
The value was already reconstructed into PREV_SP. */
|
||
if (prev_regnum == ARM_SP_REGNUM)
|
||
{
|
||
*lvalp = not_lval;
|
||
if (valuep)
|
||
store_unsigned_integer (valuep, 4, cache->prev_sp);
|
||
return;
|
||
}
|
||
|
||
trad_frame_get_prev_register (next_frame, cache->saved_regs, prev_regnum,
|
||
optimized, lvalp, addrp, realnump, valuep);
|
||
}
|
||
|
||
struct frame_unwind arm_prologue_unwind = {
|
||
NORMAL_FRAME,
|
||
arm_prologue_this_id,
|
||
arm_prologue_prev_register
|
||
};
|
||
|
||
static const struct frame_unwind *
|
||
arm_prologue_unwind_sniffer (struct frame_info *next_frame)
|
||
{
|
||
return &arm_prologue_unwind;
|
||
}
|
||
|
||
static struct arm_prologue_cache *
|
||
arm_make_stub_cache (struct frame_info *next_frame)
|
||
{
|
||
int reg;
|
||
struct arm_prologue_cache *cache;
|
||
CORE_ADDR unwound_fp;
|
||
|
||
cache = frame_obstack_zalloc (sizeof (struct arm_prologue_cache));
|
||
cache->saved_regs = trad_frame_alloc_saved_regs (next_frame);
|
||
|
||
cache->prev_sp = frame_unwind_register_unsigned (next_frame, ARM_SP_REGNUM);
|
||
|
||
return cache;
|
||
}
|
||
|
||
/* Our frame ID for a stub frame is the current SP and LR. */
|
||
|
||
static void
|
||
arm_stub_this_id (struct frame_info *next_frame,
|
||
void **this_cache,
|
||
struct frame_id *this_id)
|
||
{
|
||
struct arm_prologue_cache *cache;
|
||
|
||
if (*this_cache == NULL)
|
||
*this_cache = arm_make_stub_cache (next_frame);
|
||
cache = *this_cache;
|
||
|
||
*this_id = frame_id_build (cache->prev_sp,
|
||
frame_pc_unwind (next_frame));
|
||
}
|
||
|
||
struct frame_unwind arm_stub_unwind = {
|
||
NORMAL_FRAME,
|
||
arm_stub_this_id,
|
||
arm_prologue_prev_register
|
||
};
|
||
|
||
static const struct frame_unwind *
|
||
arm_stub_unwind_sniffer (struct frame_info *next_frame)
|
||
{
|
||
char dummy[4];
|
||
|
||
if (in_plt_section (frame_unwind_address_in_block (next_frame), NULL)
|
||
|| target_read_memory (frame_pc_unwind (next_frame), dummy, 4) != 0)
|
||
return &arm_stub_unwind;
|
||
|
||
return NULL;
|
||
}
|
||
|
||
static CORE_ADDR
|
||
arm_normal_frame_base (struct frame_info *next_frame, void **this_cache)
|
||
{
|
||
struct arm_prologue_cache *cache;
|
||
|
||
if (*this_cache == NULL)
|
||
*this_cache = arm_make_prologue_cache (next_frame);
|
||
cache = *this_cache;
|
||
|
||
return cache->prev_sp + cache->frameoffset - cache->framesize;
|
||
}
|
||
|
||
struct frame_base arm_normal_base = {
|
||
&arm_prologue_unwind,
|
||
arm_normal_frame_base,
|
||
arm_normal_frame_base,
|
||
arm_normal_frame_base
|
||
};
|
||
|
||
/* Assuming NEXT_FRAME->prev is a dummy, return the frame ID of that
|
||
dummy frame. The frame ID's base needs to match the TOS value
|
||
saved by save_dummy_frame_tos() and returned from
|
||
arm_push_dummy_call, and the PC needs to match the dummy frame's
|
||
breakpoint. */
|
||
|
||
static struct frame_id
|
||
arm_unwind_dummy_id (struct gdbarch *gdbarch, struct frame_info *next_frame)
|
||
{
|
||
return frame_id_build (frame_unwind_register_unsigned (next_frame, ARM_SP_REGNUM),
|
||
frame_pc_unwind (next_frame));
|
||
}
|
||
|
||
/* Given THIS_FRAME, find the previous frame's resume PC (which will
|
||
be used to construct the previous frame's ID, after looking up the
|
||
containing function). */
|
||
|
||
static CORE_ADDR
|
||
arm_unwind_pc (struct gdbarch *gdbarch, struct frame_info *this_frame)
|
||
{
|
||
CORE_ADDR pc;
|
||
pc = frame_unwind_register_unsigned (this_frame, ARM_PC_REGNUM);
|
||
return ADDR_BITS_REMOVE (pc);
|
||
}
|
||
|
||
static CORE_ADDR
|
||
arm_unwind_sp (struct gdbarch *gdbarch, struct frame_info *this_frame)
|
||
{
|
||
return frame_unwind_register_unsigned (this_frame, ARM_SP_REGNUM);
|
||
}
|
||
|
||
/* When arguments must be pushed onto the stack, they go on in reverse
|
||
order. The code below implements a FILO (stack) to do this. */
|
||
|
||
struct stack_item
|
||
{
|
||
int len;
|
||
struct stack_item *prev;
|
||
void *data;
|
||
};
|
||
|
||
static struct stack_item *
|
||
push_stack_item (struct stack_item *prev, void *contents, int len)
|
||
{
|
||
struct stack_item *si;
|
||
si = xmalloc (sizeof (struct stack_item));
|
||
si->data = xmalloc (len);
|
||
si->len = len;
|
||
si->prev = prev;
|
||
memcpy (si->data, contents, len);
|
||
return si;
|
||
}
|
||
|
||
static struct stack_item *
|
||
pop_stack_item (struct stack_item *si)
|
||
{
|
||
struct stack_item *dead = si;
|
||
si = si->prev;
|
||
xfree (dead->data);
|
||
xfree (dead);
|
||
return si;
|
||
}
|
||
|
||
|
||
/* Return the alignment (in bytes) of the given type. */
|
||
|
||
static int
|
||
arm_type_align (struct type *t)
|
||
{
|
||
int n;
|
||
int align;
|
||
int falign;
|
||
|
||
t = check_typedef (t);
|
||
switch (TYPE_CODE (t))
|
||
{
|
||
default:
|
||
/* Should never happen. */
|
||
internal_error (__FILE__, __LINE__, _("unknown type alignment"));
|
||
return 4;
|
||
|
||
case TYPE_CODE_PTR:
|
||
case TYPE_CODE_ENUM:
|
||
case TYPE_CODE_INT:
|
||
case TYPE_CODE_FLT:
|
||
case TYPE_CODE_SET:
|
||
case TYPE_CODE_RANGE:
|
||
case TYPE_CODE_BITSTRING:
|
||
case TYPE_CODE_REF:
|
||
case TYPE_CODE_CHAR:
|
||
case TYPE_CODE_BOOL:
|
||
return TYPE_LENGTH (t);
|
||
|
||
case TYPE_CODE_ARRAY:
|
||
case TYPE_CODE_COMPLEX:
|
||
/* TODO: What about vector types? */
|
||
return arm_type_align (TYPE_TARGET_TYPE (t));
|
||
|
||
case TYPE_CODE_STRUCT:
|
||
case TYPE_CODE_UNION:
|
||
align = 1;
|
||
for (n = 0; n < TYPE_NFIELDS (t); n++)
|
||
{
|
||
falign = arm_type_align (TYPE_FIELD_TYPE (t, n));
|
||
if (falign > align)
|
||
align = falign;
|
||
}
|
||
return align;
|
||
}
|
||
}
|
||
|
||
/* We currently only support passing parameters in integer registers. This
|
||
conforms with GCC's default model. Several other variants exist and
|
||
we should probably support some of them based on the selected ABI. */
|
||
|
||
static CORE_ADDR
|
||
arm_push_dummy_call (struct gdbarch *gdbarch, struct value *function,
|
||
struct regcache *regcache, CORE_ADDR bp_addr, int nargs,
|
||
struct value **args, CORE_ADDR sp, int struct_return,
|
||
CORE_ADDR struct_addr)
|
||
{
|
||
int argnum;
|
||
int argreg;
|
||
int nstack;
|
||
struct stack_item *si = NULL;
|
||
|
||
/* Set the return address. For the ARM, the return breakpoint is
|
||
always at BP_ADDR. */
|
||
/* XXX Fix for Thumb. */
|
||
regcache_cooked_write_unsigned (regcache, ARM_LR_REGNUM, bp_addr);
|
||
|
||
/* Walk through the list of args and determine how large a temporary
|
||
stack is required. Need to take care here as structs may be
|
||
passed on the stack, and we have to to push them. */
|
||
nstack = 0;
|
||
|
||
argreg = ARM_A1_REGNUM;
|
||
nstack = 0;
|
||
|
||
/* The struct_return pointer occupies the first parameter
|
||
passing register. */
|
||
if (struct_return)
|
||
{
|
||
if (arm_debug)
|
||
fprintf_unfiltered (gdb_stdlog, "struct return in %s = 0x%s\n",
|
||
REGISTER_NAME (argreg), paddr (struct_addr));
|
||
regcache_cooked_write_unsigned (regcache, argreg, struct_addr);
|
||
argreg++;
|
||
}
|
||
|
||
for (argnum = 0; argnum < nargs; argnum++)
|
||
{
|
||
int len;
|
||
struct type *arg_type;
|
||
struct type *target_type;
|
||
enum type_code typecode;
|
||
bfd_byte *val;
|
||
int align;
|
||
|
||
arg_type = check_typedef (value_type (args[argnum]));
|
||
len = TYPE_LENGTH (arg_type);
|
||
target_type = TYPE_TARGET_TYPE (arg_type);
|
||
typecode = TYPE_CODE (arg_type);
|
||
val = value_contents_writeable (args[argnum]);
|
||
|
||
align = arm_type_align (arg_type);
|
||
/* Round alignment up to a whole number of words. */
|
||
align = (align + INT_REGISTER_SIZE - 1) & ~(INT_REGISTER_SIZE - 1);
|
||
/* Different ABIs have different maximum alignments. */
|
||
if (gdbarch_tdep (gdbarch)->arm_abi == ARM_ABI_APCS)
|
||
{
|
||
/* The APCS ABI only requires word alignment. */
|
||
align = INT_REGISTER_SIZE;
|
||
}
|
||
else
|
||
{
|
||
/* The AAPCS requires at most doubleword alignment. */
|
||
if (align > INT_REGISTER_SIZE * 2)
|
||
align = INT_REGISTER_SIZE * 2;
|
||
}
|
||
|
||
/* Push stack padding for dowubleword alignment. */
|
||
if (nstack & (align - 1))
|
||
{
|
||
si = push_stack_item (si, val, INT_REGISTER_SIZE);
|
||
nstack += INT_REGISTER_SIZE;
|
||
}
|
||
|
||
/* Doubleword aligned quantities must go in even register pairs. */
|
||
if (argreg <= ARM_LAST_ARG_REGNUM
|
||
&& align > INT_REGISTER_SIZE
|
||
&& argreg & 1)
|
||
argreg++;
|
||
|
||
/* If the argument is a pointer to a function, and it is a
|
||
Thumb function, create a LOCAL copy of the value and set
|
||
the THUMB bit in it. */
|
||
if (TYPE_CODE_PTR == typecode
|
||
&& target_type != NULL
|
||
&& TYPE_CODE_FUNC == TYPE_CODE (target_type))
|
||
{
|
||
CORE_ADDR regval = extract_unsigned_integer (val, len);
|
||
if (arm_pc_is_thumb (regval))
|
||
{
|
||
val = alloca (len);
|
||
store_unsigned_integer (val, len, MAKE_THUMB_ADDR (regval));
|
||
}
|
||
}
|
||
|
||
/* Copy the argument to general registers or the stack in
|
||
register-sized pieces. Large arguments are split between
|
||
registers and stack. */
|
||
while (len > 0)
|
||
{
|
||
int partial_len = len < DEPRECATED_REGISTER_SIZE ? len : DEPRECATED_REGISTER_SIZE;
|
||
|
||
if (argreg <= ARM_LAST_ARG_REGNUM)
|
||
{
|
||
/* The argument is being passed in a general purpose
|
||
register. */
|
||
CORE_ADDR regval = extract_unsigned_integer (val, partial_len);
|
||
if (arm_debug)
|
||
fprintf_unfiltered (gdb_stdlog, "arg %d in %s = 0x%s\n",
|
||
argnum, REGISTER_NAME (argreg),
|
||
phex (regval, DEPRECATED_REGISTER_SIZE));
|
||
regcache_cooked_write_unsigned (regcache, argreg, regval);
|
||
argreg++;
|
||
}
|
||
else
|
||
{
|
||
/* Push the arguments onto the stack. */
|
||
if (arm_debug)
|
||
fprintf_unfiltered (gdb_stdlog, "arg %d @ sp + %d\n",
|
||
argnum, nstack);
|
||
si = push_stack_item (si, val, DEPRECATED_REGISTER_SIZE);
|
||
nstack += DEPRECATED_REGISTER_SIZE;
|
||
}
|
||
|
||
len -= partial_len;
|
||
val += partial_len;
|
||
}
|
||
}
|
||
/* If we have an odd number of words to push, then decrement the stack
|
||
by one word now, so first stack argument will be dword aligned. */
|
||
if (nstack & 4)
|
||
sp -= 4;
|
||
|
||
while (si)
|
||
{
|
||
sp -= si->len;
|
||
write_memory (sp, si->data, si->len);
|
||
si = pop_stack_item (si);
|
||
}
|
||
|
||
/* Finally, update teh SP register. */
|
||
regcache_cooked_write_unsigned (regcache, ARM_SP_REGNUM, sp);
|
||
|
||
return sp;
|
||
}
|
||
|
||
|
||
/* Always align the frame to an 8-byte boundary. This is required on
|
||
some platforms and harmless on the rest. */
|
||
|
||
static CORE_ADDR
|
||
arm_frame_align (struct gdbarch *gdbarch, CORE_ADDR sp)
|
||
{
|
||
/* Align the stack to eight bytes. */
|
||
return sp & ~ (CORE_ADDR) 7;
|
||
}
|
||
|
||
static void
|
||
print_fpu_flags (int flags)
|
||
{
|
||
if (flags & (1 << 0))
|
||
fputs ("IVO ", stdout);
|
||
if (flags & (1 << 1))
|
||
fputs ("DVZ ", stdout);
|
||
if (flags & (1 << 2))
|
||
fputs ("OFL ", stdout);
|
||
if (flags & (1 << 3))
|
||
fputs ("UFL ", stdout);
|
||
if (flags & (1 << 4))
|
||
fputs ("INX ", stdout);
|
||
putchar ('\n');
|
||
}
|
||
|
||
/* Print interesting information about the floating point processor
|
||
(if present) or emulator. */
|
||
static void
|
||
arm_print_float_info (struct gdbarch *gdbarch, struct ui_file *file,
|
||
struct frame_info *frame, const char *args)
|
||
{
|
||
unsigned long status = read_register (ARM_FPS_REGNUM);
|
||
int type;
|
||
|
||
type = (status >> 24) & 127;
|
||
if (status & (1 << 31))
|
||
printf (_("Hardware FPU type %d\n"), type);
|
||
else
|
||
printf (_("Software FPU type %d\n"), type);
|
||
/* i18n: [floating point unit] mask */
|
||
fputs (_("mask: "), stdout);
|
||
print_fpu_flags (status >> 16);
|
||
/* i18n: [floating point unit] flags */
|
||
fputs (_("flags: "), stdout);
|
||
print_fpu_flags (status);
|
||
}
|
||
|
||
/* Return the GDB type object for the "standard" data type of data in
|
||
register N. */
|
||
|
||
static struct type *
|
||
arm_register_type (struct gdbarch *gdbarch, int regnum)
|
||
{
|
||
if (regnum >= ARM_F0_REGNUM && regnum < ARM_F0_REGNUM + NUM_FREGS)
|
||
{
|
||
if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG)
|
||
return builtin_type_arm_ext_big;
|
||
else
|
||
return builtin_type_arm_ext_littlebyte_bigword;
|
||
}
|
||
else
|
||
return builtin_type_int32;
|
||
}
|
||
|
||
/* Index within `registers' of the first byte of the space for
|
||
register N. */
|
||
|
||
static int
|
||
arm_register_byte (int regnum)
|
||
{
|
||
if (regnum < ARM_F0_REGNUM)
|
||
return regnum * INT_REGISTER_SIZE;
|
||
else if (regnum < ARM_PS_REGNUM)
|
||
return (NUM_GREGS * INT_REGISTER_SIZE
|
||
+ (regnum - ARM_F0_REGNUM) * FP_REGISTER_SIZE);
|
||
else
|
||
return (NUM_GREGS * INT_REGISTER_SIZE
|
||
+ NUM_FREGS * FP_REGISTER_SIZE
|
||
+ (regnum - ARM_FPS_REGNUM) * STATUS_REGISTER_SIZE);
|
||
}
|
||
|
||
/* Map GDB internal REGNUM onto the Arm simulator register numbers. */
|
||
static int
|
||
arm_register_sim_regno (int regnum)
|
||
{
|
||
int reg = regnum;
|
||
gdb_assert (reg >= 0 && reg < NUM_REGS);
|
||
|
||
if (reg < NUM_GREGS)
|
||
return SIM_ARM_R0_REGNUM + reg;
|
||
reg -= NUM_GREGS;
|
||
|
||
if (reg < NUM_FREGS)
|
||
return SIM_ARM_FP0_REGNUM + reg;
|
||
reg -= NUM_FREGS;
|
||
|
||
if (reg < NUM_SREGS)
|
||
return SIM_ARM_FPS_REGNUM + reg;
|
||
reg -= NUM_SREGS;
|
||
|
||
internal_error (__FILE__, __LINE__, _("Bad REGNUM %d"), regnum);
|
||
}
|
||
|
||
/* NOTE: cagney/2001-08-20: Both convert_from_extended() and
|
||
convert_to_extended() use floatformat_arm_ext_littlebyte_bigword.
|
||
It is thought that this is is the floating-point register format on
|
||
little-endian systems. */
|
||
|
||
static void
|
||
convert_from_extended (const struct floatformat *fmt, const void *ptr,
|
||
void *dbl)
|
||
{
|
||
DOUBLEST d;
|
||
if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG)
|
||
floatformat_to_doublest (&floatformat_arm_ext_big, ptr, &d);
|
||
else
|
||
floatformat_to_doublest (&floatformat_arm_ext_littlebyte_bigword,
|
||
ptr, &d);
|
||
floatformat_from_doublest (fmt, &d, dbl);
|
||
}
|
||
|
||
static void
|
||
convert_to_extended (const struct floatformat *fmt, void *dbl, const void *ptr)
|
||
{
|
||
DOUBLEST d;
|
||
floatformat_to_doublest (fmt, ptr, &d);
|
||
if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG)
|
||
floatformat_from_doublest (&floatformat_arm_ext_big, &d, dbl);
|
||
else
|
||
floatformat_from_doublest (&floatformat_arm_ext_littlebyte_bigword,
|
||
&d, dbl);
|
||
}
|
||
|
||
static int
|
||
condition_true (unsigned long cond, unsigned long status_reg)
|
||
{
|
||
if (cond == INST_AL || cond == INST_NV)
|
||
return 1;
|
||
|
||
switch (cond)
|
||
{
|
||
case INST_EQ:
|
||
return ((status_reg & FLAG_Z) != 0);
|
||
case INST_NE:
|
||
return ((status_reg & FLAG_Z) == 0);
|
||
case INST_CS:
|
||
return ((status_reg & FLAG_C) != 0);
|
||
case INST_CC:
|
||
return ((status_reg & FLAG_C) == 0);
|
||
case INST_MI:
|
||
return ((status_reg & FLAG_N) != 0);
|
||
case INST_PL:
|
||
return ((status_reg & FLAG_N) == 0);
|
||
case INST_VS:
|
||
return ((status_reg & FLAG_V) != 0);
|
||
case INST_VC:
|
||
return ((status_reg & FLAG_V) == 0);
|
||
case INST_HI:
|
||
return ((status_reg & (FLAG_C | FLAG_Z)) == FLAG_C);
|
||
case INST_LS:
|
||
return ((status_reg & (FLAG_C | FLAG_Z)) != FLAG_C);
|
||
case INST_GE:
|
||
return (((status_reg & FLAG_N) == 0) == ((status_reg & FLAG_V) == 0));
|
||
case INST_LT:
|
||
return (((status_reg & FLAG_N) == 0) != ((status_reg & FLAG_V) == 0));
|
||
case INST_GT:
|
||
return (((status_reg & FLAG_Z) == 0) &&
|
||
(((status_reg & FLAG_N) == 0) == ((status_reg & FLAG_V) == 0)));
|
||
case INST_LE:
|
||
return (((status_reg & FLAG_Z) != 0) ||
|
||
(((status_reg & FLAG_N) == 0) != ((status_reg & FLAG_V) == 0)));
|
||
}
|
||
return 1;
|
||
}
|
||
|
||
/* Support routines for single stepping. Calculate the next PC value. */
|
||
#define submask(x) ((1L << ((x) + 1)) - 1)
|
||
#define bit(obj,st) (((obj) >> (st)) & 1)
|
||
#define bits(obj,st,fn) (((obj) >> (st)) & submask ((fn) - (st)))
|
||
#define sbits(obj,st,fn) \
|
||
((long) (bits(obj,st,fn) | ((long) bit(obj,fn) * ~ submask (fn - st))))
|
||
#define BranchDest(addr,instr) \
|
||
((CORE_ADDR) (((long) (addr)) + 8 + (sbits (instr, 0, 23) << 2)))
|
||
#define ARM_PC_32 1
|
||
|
||
static unsigned long
|
||
shifted_reg_val (unsigned long inst, int carry, unsigned long pc_val,
|
||
unsigned long status_reg)
|
||
{
|
||
unsigned long res, shift;
|
||
int rm = bits (inst, 0, 3);
|
||
unsigned long shifttype = bits (inst, 5, 6);
|
||
|
||
if (bit (inst, 4))
|
||
{
|
||
int rs = bits (inst, 8, 11);
|
||
shift = (rs == 15 ? pc_val + 8 : read_register (rs)) & 0xFF;
|
||
}
|
||
else
|
||
shift = bits (inst, 7, 11);
|
||
|
||
res = (rm == 15
|
||
? ((pc_val | (ARM_PC_32 ? 0 : status_reg))
|
||
+ (bit (inst, 4) ? 12 : 8))
|
||
: read_register (rm));
|
||
|
||
switch (shifttype)
|
||
{
|
||
case 0: /* LSL */
|
||
res = shift >= 32 ? 0 : res << shift;
|
||
break;
|
||
|
||
case 1: /* LSR */
|
||
res = shift >= 32 ? 0 : res >> shift;
|
||
break;
|
||
|
||
case 2: /* ASR */
|
||
if (shift >= 32)
|
||
shift = 31;
|
||
res = ((res & 0x80000000L)
|
||
? ~((~res) >> shift) : res >> shift);
|
||
break;
|
||
|
||
case 3: /* ROR/RRX */
|
||
shift &= 31;
|
||
if (shift == 0)
|
||
res = (res >> 1) | (carry ? 0x80000000L : 0);
|
||
else
|
||
res = (res >> shift) | (res << (32 - shift));
|
||
break;
|
||
}
|
||
|
||
return res & 0xffffffff;
|
||
}
|
||
|
||
/* Return number of 1-bits in VAL. */
|
||
|
||
static int
|
||
bitcount (unsigned long val)
|
||
{
|
||
int nbits;
|
||
for (nbits = 0; val != 0; nbits++)
|
||
val &= val - 1; /* delete rightmost 1-bit in val */
|
||
return nbits;
|
||
}
|
||
|
||
CORE_ADDR
|
||
thumb_get_next_pc (CORE_ADDR pc)
|
||
{
|
||
unsigned long pc_val = ((unsigned long) pc) + 4; /* PC after prefetch */
|
||
unsigned short inst1 = read_memory_unsigned_integer (pc, 2);
|
||
CORE_ADDR nextpc = pc + 2; /* default is next instruction */
|
||
unsigned long offset;
|
||
|
||
if ((inst1 & 0xff00) == 0xbd00) /* pop {rlist, pc} */
|
||
{
|
||
CORE_ADDR sp;
|
||
|
||
/* Fetch the saved PC from the stack. It's stored above
|
||
all of the other registers. */
|
||
offset = bitcount (bits (inst1, 0, 7)) * DEPRECATED_REGISTER_SIZE;
|
||
sp = read_register (ARM_SP_REGNUM);
|
||
nextpc = (CORE_ADDR) read_memory_unsigned_integer (sp + offset, 4);
|
||
nextpc = ADDR_BITS_REMOVE (nextpc);
|
||
if (nextpc == pc)
|
||
error (_("Infinite loop detected"));
|
||
}
|
||
else if ((inst1 & 0xf000) == 0xd000) /* conditional branch */
|
||
{
|
||
unsigned long status = read_register (ARM_PS_REGNUM);
|
||
unsigned long cond = bits (inst1, 8, 11);
|
||
if (cond != 0x0f && condition_true (cond, status)) /* 0x0f = SWI */
|
||
nextpc = pc_val + (sbits (inst1, 0, 7) << 1);
|
||
}
|
||
else if ((inst1 & 0xf800) == 0xe000) /* unconditional branch */
|
||
{
|
||
nextpc = pc_val + (sbits (inst1, 0, 10) << 1);
|
||
}
|
||
else if ((inst1 & 0xf800) == 0xf000) /* long branch with link, and blx */
|
||
{
|
||
unsigned short inst2 = read_memory_unsigned_integer (pc + 2, 2);
|
||
offset = (sbits (inst1, 0, 10) << 12) + (bits (inst2, 0, 10) << 1);
|
||
nextpc = pc_val + offset;
|
||
/* For BLX make sure to clear the low bits. */
|
||
if (bits (inst2, 11, 12) == 1)
|
||
nextpc = nextpc & 0xfffffffc;
|
||
}
|
||
else if ((inst1 & 0xff00) == 0x4700) /* bx REG, blx REG */
|
||
{
|
||
if (bits (inst1, 3, 6) == 0x0f)
|
||
nextpc = pc_val;
|
||
else
|
||
nextpc = read_register (bits (inst1, 3, 6));
|
||
|
||
nextpc = ADDR_BITS_REMOVE (nextpc);
|
||
if (nextpc == pc)
|
||
error (_("Infinite loop detected"));
|
||
}
|
||
|
||
return nextpc;
|
||
}
|
||
|
||
CORE_ADDR
|
||
arm_get_next_pc (CORE_ADDR pc)
|
||
{
|
||
unsigned long pc_val;
|
||
unsigned long this_instr;
|
||
unsigned long status;
|
||
CORE_ADDR nextpc;
|
||
|
||
if (arm_pc_is_thumb (pc))
|
||
return thumb_get_next_pc (pc);
|
||
|
||
pc_val = (unsigned long) pc;
|
||
this_instr = read_memory_unsigned_integer (pc, 4);
|
||
status = read_register (ARM_PS_REGNUM);
|
||
nextpc = (CORE_ADDR) (pc_val + 4); /* Default case */
|
||
|
||
if (condition_true (bits (this_instr, 28, 31), status))
|
||
{
|
||
switch (bits (this_instr, 24, 27))
|
||
{
|
||
case 0x0:
|
||
case 0x1: /* data processing */
|
||
case 0x2:
|
||
case 0x3:
|
||
{
|
||
unsigned long operand1, operand2, result = 0;
|
||
unsigned long rn;
|
||
int c;
|
||
|
||
if (bits (this_instr, 12, 15) != 15)
|
||
break;
|
||
|
||
if (bits (this_instr, 22, 25) == 0
|
||
&& bits (this_instr, 4, 7) == 9) /* multiply */
|
||
error (_("Invalid update to pc in instruction"));
|
||
|
||
/* BX <reg>, BLX <reg> */
|
||
if (bits (this_instr, 4, 28) == 0x12fff1
|
||
|| bits (this_instr, 4, 28) == 0x12fff3)
|
||
{
|
||
rn = bits (this_instr, 0, 3);
|
||
result = (rn == 15) ? pc_val + 8 : read_register (rn);
|
||
nextpc = (CORE_ADDR) ADDR_BITS_REMOVE (result);
|
||
|
||
if (nextpc == pc)
|
||
error (_("Infinite loop detected"));
|
||
|
||
return nextpc;
|
||
}
|
||
|
||
/* Multiply into PC */
|
||
c = (status & FLAG_C) ? 1 : 0;
|
||
rn = bits (this_instr, 16, 19);
|
||
operand1 = (rn == 15) ? pc_val + 8 : read_register (rn);
|
||
|
||
if (bit (this_instr, 25))
|
||
{
|
||
unsigned long immval = bits (this_instr, 0, 7);
|
||
unsigned long rotate = 2 * bits (this_instr, 8, 11);
|
||
operand2 = ((immval >> rotate) | (immval << (32 - rotate)))
|
||
& 0xffffffff;
|
||
}
|
||
else /* operand 2 is a shifted register */
|
||
operand2 = shifted_reg_val (this_instr, c, pc_val, status);
|
||
|
||
switch (bits (this_instr, 21, 24))
|
||
{
|
||
case 0x0: /*and */
|
||
result = operand1 & operand2;
|
||
break;
|
||
|
||
case 0x1: /*eor */
|
||
result = operand1 ^ operand2;
|
||
break;
|
||
|
||
case 0x2: /*sub */
|
||
result = operand1 - operand2;
|
||
break;
|
||
|
||
case 0x3: /*rsb */
|
||
result = operand2 - operand1;
|
||
break;
|
||
|
||
case 0x4: /*add */
|
||
result = operand1 + operand2;
|
||
break;
|
||
|
||
case 0x5: /*adc */
|
||
result = operand1 + operand2 + c;
|
||
break;
|
||
|
||
case 0x6: /*sbc */
|
||
result = operand1 - operand2 + c;
|
||
break;
|
||
|
||
case 0x7: /*rsc */
|
||
result = operand2 - operand1 + c;
|
||
break;
|
||
|
||
case 0x8:
|
||
case 0x9:
|
||
case 0xa:
|
||
case 0xb: /* tst, teq, cmp, cmn */
|
||
result = (unsigned long) nextpc;
|
||
break;
|
||
|
||
case 0xc: /*orr */
|
||
result = operand1 | operand2;
|
||
break;
|
||
|
||
case 0xd: /*mov */
|
||
/* Always step into a function. */
|
||
result = operand2;
|
||
break;
|
||
|
||
case 0xe: /*bic */
|
||
result = operand1 & ~operand2;
|
||
break;
|
||
|
||
case 0xf: /*mvn */
|
||
result = ~operand2;
|
||
break;
|
||
}
|
||
nextpc = (CORE_ADDR) ADDR_BITS_REMOVE (result);
|
||
|
||
if (nextpc == pc)
|
||
error (_("Infinite loop detected"));
|
||
break;
|
||
}
|
||
|
||
case 0x4:
|
||
case 0x5: /* data transfer */
|
||
case 0x6:
|
||
case 0x7:
|
||
if (bit (this_instr, 20))
|
||
{
|
||
/* load */
|
||
if (bits (this_instr, 12, 15) == 15)
|
||
{
|
||
/* rd == pc */
|
||
unsigned long rn;
|
||
unsigned long base;
|
||
|
||
if (bit (this_instr, 22))
|
||
error (_("Invalid update to pc in instruction"));
|
||
|
||
/* byte write to PC */
|
||
rn = bits (this_instr, 16, 19);
|
||
base = (rn == 15) ? pc_val + 8 : read_register (rn);
|
||
if (bit (this_instr, 24))
|
||
{
|
||
/* pre-indexed */
|
||
int c = (status & FLAG_C) ? 1 : 0;
|
||
unsigned long offset =
|
||
(bit (this_instr, 25)
|
||
? shifted_reg_val (this_instr, c, pc_val, status)
|
||
: bits (this_instr, 0, 11));
|
||
|
||
if (bit (this_instr, 23))
|
||
base += offset;
|
||
else
|
||
base -= offset;
|
||
}
|
||
nextpc = (CORE_ADDR) read_memory_integer ((CORE_ADDR) base,
|
||
4);
|
||
|
||
nextpc = ADDR_BITS_REMOVE (nextpc);
|
||
|
||
if (nextpc == pc)
|
||
error (_("Infinite loop detected"));
|
||
}
|
||
}
|
||
break;
|
||
|
||
case 0x8:
|
||
case 0x9: /* block transfer */
|
||
if (bit (this_instr, 20))
|
||
{
|
||
/* LDM */
|
||
if (bit (this_instr, 15))
|
||
{
|
||
/* loading pc */
|
||
int offset = 0;
|
||
|
||
if (bit (this_instr, 23))
|
||
{
|
||
/* up */
|
||
unsigned long reglist = bits (this_instr, 0, 14);
|
||
offset = bitcount (reglist) * 4;
|
||
if (bit (this_instr, 24)) /* pre */
|
||
offset += 4;
|
||
}
|
||
else if (bit (this_instr, 24))
|
||
offset = -4;
|
||
|
||
{
|
||
unsigned long rn_val =
|
||
read_register (bits (this_instr, 16, 19));
|
||
nextpc =
|
||
(CORE_ADDR) read_memory_integer ((CORE_ADDR) (rn_val
|
||
+ offset),
|
||
4);
|
||
}
|
||
nextpc = ADDR_BITS_REMOVE (nextpc);
|
||
if (nextpc == pc)
|
||
error (_("Infinite loop detected"));
|
||
}
|
||
}
|
||
break;
|
||
|
||
case 0xb: /* branch & link */
|
||
case 0xa: /* branch */
|
||
{
|
||
nextpc = BranchDest (pc, this_instr);
|
||
|
||
/* BLX */
|
||
if (bits (this_instr, 28, 31) == INST_NV)
|
||
nextpc |= bit (this_instr, 24) << 1;
|
||
|
||
nextpc = ADDR_BITS_REMOVE (nextpc);
|
||
if (nextpc == pc)
|
||
error (_("Infinite loop detected"));
|
||
break;
|
||
}
|
||
|
||
case 0xc:
|
||
case 0xd:
|
||
case 0xe: /* coproc ops */
|
||
case 0xf: /* SWI */
|
||
break;
|
||
|
||
default:
|
||
fprintf_filtered (gdb_stderr, _("Bad bit-field extraction\n"));
|
||
return (pc);
|
||
}
|
||
}
|
||
|
||
return nextpc;
|
||
}
|
||
|
||
/* single_step() is called just before we want to resume the inferior,
|
||
if we want to single-step it but there is no hardware or kernel
|
||
single-step support. We find the target of the coming instruction
|
||
and breakpoint it.
|
||
|
||
single_step() is also called just after the inferior stops. If we
|
||
had set up a simulated single-step, we undo our damage. */
|
||
|
||
static void
|
||
arm_software_single_step (enum target_signal sig, int insert_bpt)
|
||
{
|
||
/* NOTE: This may insert the wrong breakpoint instruction when
|
||
single-stepping over a mode-changing instruction, if the
|
||
CPSR heuristics are used. */
|
||
|
||
if (insert_bpt)
|
||
{
|
||
CORE_ADDR next_pc = arm_get_next_pc (read_register (ARM_PC_REGNUM));
|
||
|
||
insert_single_step_breakpoint (next_pc);
|
||
}
|
||
else
|
||
remove_single_step_breakpoints ();
|
||
}
|
||
|
||
#include "bfd-in2.h"
|
||
#include "libcoff.h"
|
||
|
||
static int
|
||
gdb_print_insn_arm (bfd_vma memaddr, disassemble_info *info)
|
||
{
|
||
if (arm_pc_is_thumb (memaddr))
|
||
{
|
||
static asymbol *asym;
|
||
static combined_entry_type ce;
|
||
static struct coff_symbol_struct csym;
|
||
static struct bfd fake_bfd;
|
||
static bfd_target fake_target;
|
||
|
||
if (csym.native == NULL)
|
||
{
|
||
/* Create a fake symbol vector containing a Thumb symbol.
|
||
This is solely so that the code in print_insn_little_arm()
|
||
and print_insn_big_arm() in opcodes/arm-dis.c will detect
|
||
the presence of a Thumb symbol and switch to decoding
|
||
Thumb instructions. */
|
||
|
||
fake_target.flavour = bfd_target_coff_flavour;
|
||
fake_bfd.xvec = &fake_target;
|
||
ce.u.syment.n_sclass = C_THUMBEXTFUNC;
|
||
csym.native = &ce;
|
||
csym.symbol.the_bfd = &fake_bfd;
|
||
csym.symbol.name = "fake";
|
||
asym = (asymbol *) & csym;
|
||
}
|
||
|
||
memaddr = UNMAKE_THUMB_ADDR (memaddr);
|
||
info->symbols = &asym;
|
||
}
|
||
else
|
||
info->symbols = NULL;
|
||
|
||
if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG)
|
||
return print_insn_big_arm (memaddr, info);
|
||
else
|
||
return print_insn_little_arm (memaddr, info);
|
||
}
|
||
|
||
/* The following define instruction sequences that will cause ARM
|
||
cpu's to take an undefined instruction trap. These are used to
|
||
signal a breakpoint to GDB.
|
||
|
||
The newer ARMv4T cpu's are capable of operating in ARM or Thumb
|
||
modes. A different instruction is required for each mode. The ARM
|
||
cpu's can also be big or little endian. Thus four different
|
||
instructions are needed to support all cases.
|
||
|
||
Note: ARMv4 defines several new instructions that will take the
|
||
undefined instruction trap. ARM7TDMI is nominally ARMv4T, but does
|
||
not in fact add the new instructions. The new undefined
|
||
instructions in ARMv4 are all instructions that had no defined
|
||
behaviour in earlier chips. There is no guarantee that they will
|
||
raise an exception, but may be treated as NOP's. In practice, it
|
||
may only safe to rely on instructions matching:
|
||
|
||
3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1
|
||
1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
|
||
C C C C 0 1 1 x x x x x x x x x x x x x x x x x x x x 1 x x x x
|
||
|
||
Even this may only true if the condition predicate is true. The
|
||
following use a condition predicate of ALWAYS so it is always TRUE.
|
||
|
||
There are other ways of forcing a breakpoint. GNU/Linux, RISC iX,
|
||
and NetBSD all use a software interrupt rather than an undefined
|
||
instruction to force a trap. This can be handled by by the
|
||
abi-specific code during establishment of the gdbarch vector. */
|
||
|
||
|
||
/* NOTE rearnsha 2002-02-18: for now we allow a non-multi-arch gdb to
|
||
override these definitions. */
|
||
#ifndef ARM_LE_BREAKPOINT
|
||
#define ARM_LE_BREAKPOINT {0xFE,0xDE,0xFF,0xE7}
|
||
#endif
|
||
#ifndef ARM_BE_BREAKPOINT
|
||
#define ARM_BE_BREAKPOINT {0xE7,0xFF,0xDE,0xFE}
|
||
#endif
|
||
#ifndef THUMB_LE_BREAKPOINT
|
||
#define THUMB_LE_BREAKPOINT {0xfe,0xdf}
|
||
#endif
|
||
#ifndef THUMB_BE_BREAKPOINT
|
||
#define THUMB_BE_BREAKPOINT {0xdf,0xfe}
|
||
#endif
|
||
|
||
static const char arm_default_arm_le_breakpoint[] = ARM_LE_BREAKPOINT;
|
||
static const char arm_default_arm_be_breakpoint[] = ARM_BE_BREAKPOINT;
|
||
static const char arm_default_thumb_le_breakpoint[] = THUMB_LE_BREAKPOINT;
|
||
static const char arm_default_thumb_be_breakpoint[] = THUMB_BE_BREAKPOINT;
|
||
|
||
/* Determine the type and size of breakpoint to insert at PCPTR. Uses
|
||
the program counter value to determine whether a 16-bit or 32-bit
|
||
breakpoint should be used. It returns a pointer to a string of
|
||
bytes that encode a breakpoint instruction, stores the length of
|
||
the string to *lenptr, and adjusts the program counter (if
|
||
necessary) to point to the actual memory location where the
|
||
breakpoint should be inserted. */
|
||
|
||
/* XXX ??? from old tm-arm.h: if we're using RDP, then we're inserting
|
||
breakpoints and storing their handles instread of what was in
|
||
memory. It is nice that this is the same size as a handle -
|
||
otherwise remote-rdp will have to change. */
|
||
|
||
static const unsigned char *
|
||
arm_breakpoint_from_pc (CORE_ADDR *pcptr, int *lenptr)
|
||
{
|
||
struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
|
||
|
||
if (arm_pc_is_thumb (*pcptr))
|
||
{
|
||
*pcptr = UNMAKE_THUMB_ADDR (*pcptr);
|
||
*lenptr = tdep->thumb_breakpoint_size;
|
||
return tdep->thumb_breakpoint;
|
||
}
|
||
else
|
||
{
|
||
*lenptr = tdep->arm_breakpoint_size;
|
||
return tdep->arm_breakpoint;
|
||
}
|
||
}
|
||
|
||
/* Extract from an array REGBUF containing the (raw) register state a
|
||
function return value of type TYPE, and copy that, in virtual
|
||
format, into VALBUF. */
|
||
|
||
static void
|
||
arm_extract_return_value (struct type *type, struct regcache *regs,
|
||
gdb_byte *valbuf)
|
||
{
|
||
if (TYPE_CODE_FLT == TYPE_CODE (type))
|
||
{
|
||
switch (gdbarch_tdep (current_gdbarch)->fp_model)
|
||
{
|
||
case ARM_FLOAT_FPA:
|
||
{
|
||
/* The value is in register F0 in internal format. We need to
|
||
extract the raw value and then convert it to the desired
|
||
internal type. */
|
||
bfd_byte tmpbuf[FP_REGISTER_SIZE];
|
||
|
||
regcache_cooked_read (regs, ARM_F0_REGNUM, tmpbuf);
|
||
convert_from_extended (floatformat_from_type (type), tmpbuf,
|
||
valbuf);
|
||
}
|
||
break;
|
||
|
||
case ARM_FLOAT_SOFT_FPA:
|
||
case ARM_FLOAT_SOFT_VFP:
|
||
regcache_cooked_read (regs, ARM_A1_REGNUM, valbuf);
|
||
if (TYPE_LENGTH (type) > 4)
|
||
regcache_cooked_read (regs, ARM_A1_REGNUM + 1,
|
||
valbuf + INT_REGISTER_SIZE);
|
||
break;
|
||
|
||
default:
|
||
internal_error
|
||
(__FILE__, __LINE__,
|
||
_("arm_extract_return_value: Floating point model not supported"));
|
||
break;
|
||
}
|
||
}
|
||
else if (TYPE_CODE (type) == TYPE_CODE_INT
|
||
|| TYPE_CODE (type) == TYPE_CODE_CHAR
|
||
|| TYPE_CODE (type) == TYPE_CODE_BOOL
|
||
|| TYPE_CODE (type) == TYPE_CODE_PTR
|
||
|| TYPE_CODE (type) == TYPE_CODE_REF
|
||
|| TYPE_CODE (type) == TYPE_CODE_ENUM)
|
||
{
|
||
/* If the the type is a plain integer, then the access is
|
||
straight-forward. Otherwise we have to play around a bit more. */
|
||
int len = TYPE_LENGTH (type);
|
||
int regno = ARM_A1_REGNUM;
|
||
ULONGEST tmp;
|
||
|
||
while (len > 0)
|
||
{
|
||
/* By using store_unsigned_integer we avoid having to do
|
||
anything special for small big-endian values. */
|
||
regcache_cooked_read_unsigned (regs, regno++, &tmp);
|
||
store_unsigned_integer (valbuf,
|
||
(len > INT_REGISTER_SIZE
|
||
? INT_REGISTER_SIZE : len),
|
||
tmp);
|
||
len -= INT_REGISTER_SIZE;
|
||
valbuf += INT_REGISTER_SIZE;
|
||
}
|
||
}
|
||
else
|
||
{
|
||
/* For a structure or union the behaviour is as if the value had
|
||
been stored to word-aligned memory and then loaded into
|
||
registers with 32-bit load instruction(s). */
|
||
int len = TYPE_LENGTH (type);
|
||
int regno = ARM_A1_REGNUM;
|
||
bfd_byte tmpbuf[INT_REGISTER_SIZE];
|
||
|
||
while (len > 0)
|
||
{
|
||
regcache_cooked_read (regs, regno++, tmpbuf);
|
||
memcpy (valbuf, tmpbuf,
|
||
len > INT_REGISTER_SIZE ? INT_REGISTER_SIZE : len);
|
||
len -= INT_REGISTER_SIZE;
|
||
valbuf += INT_REGISTER_SIZE;
|
||
}
|
||
}
|
||
}
|
||
|
||
|
||
/* Will a function return an aggregate type in memory or in a
|
||
register? Return 0 if an aggregate type can be returned in a
|
||
register, 1 if it must be returned in memory. */
|
||
|
||
static int
|
||
arm_return_in_memory (struct gdbarch *gdbarch, struct type *type)
|
||
{
|
||
int nRc;
|
||
enum type_code code;
|
||
|
||
CHECK_TYPEDEF (type);
|
||
|
||
/* In the ARM ABI, "integer" like aggregate types are returned in
|
||
registers. For an aggregate type to be integer like, its size
|
||
must be less than or equal to DEPRECATED_REGISTER_SIZE and the
|
||
offset of each addressable subfield must be zero. Note that bit
|
||
fields are not addressable, and all addressable subfields of
|
||
unions always start at offset zero.
|
||
|
||
This function is based on the behaviour of GCC 2.95.1.
|
||
See: gcc/arm.c: arm_return_in_memory() for details.
|
||
|
||
Note: All versions of GCC before GCC 2.95.2 do not set up the
|
||
parameters correctly for a function returning the following
|
||
structure: struct { float f;}; This should be returned in memory,
|
||
not a register. Richard Earnshaw sent me a patch, but I do not
|
||
know of any way to detect if a function like the above has been
|
||
compiled with the correct calling convention. */
|
||
|
||
/* All aggregate types that won't fit in a register must be returned
|
||
in memory. */
|
||
if (TYPE_LENGTH (type) > DEPRECATED_REGISTER_SIZE)
|
||
{
|
||
return 1;
|
||
}
|
||
|
||
/* The AAPCS says all aggregates not larger than a word are returned
|
||
in a register. */
|
||
if (gdbarch_tdep (gdbarch)->arm_abi != ARM_ABI_APCS)
|
||
return 0;
|
||
|
||
/* The only aggregate types that can be returned in a register are
|
||
structs and unions. Arrays must be returned in memory. */
|
||
code = TYPE_CODE (type);
|
||
if ((TYPE_CODE_STRUCT != code) && (TYPE_CODE_UNION != code))
|
||
{
|
||
return 1;
|
||
}
|
||
|
||
/* Assume all other aggregate types can be returned in a register.
|
||
Run a check for structures, unions and arrays. */
|
||
nRc = 0;
|
||
|
||
if ((TYPE_CODE_STRUCT == code) || (TYPE_CODE_UNION == code))
|
||
{
|
||
int i;
|
||
/* Need to check if this struct/union is "integer" like. For
|
||
this to be true, its size must be less than or equal to
|
||
DEPRECATED_REGISTER_SIZE and the offset of each addressable
|
||
subfield must be zero. Note that bit fields are not
|
||
addressable, and unions always start at offset zero. If any
|
||
of the subfields is a floating point type, the struct/union
|
||
cannot be an integer type. */
|
||
|
||
/* For each field in the object, check:
|
||
1) Is it FP? --> yes, nRc = 1;
|
||
2) Is it addressable (bitpos != 0) and
|
||
not packed (bitsize == 0)?
|
||
--> yes, nRc = 1
|
||
*/
|
||
|
||
for (i = 0; i < TYPE_NFIELDS (type); i++)
|
||
{
|
||
enum type_code field_type_code;
|
||
field_type_code = TYPE_CODE (check_typedef (TYPE_FIELD_TYPE (type, i)));
|
||
|
||
/* Is it a floating point type field? */
|
||
if (field_type_code == TYPE_CODE_FLT)
|
||
{
|
||
nRc = 1;
|
||
break;
|
||
}
|
||
|
||
/* If bitpos != 0, then we have to care about it. */
|
||
if (TYPE_FIELD_BITPOS (type, i) != 0)
|
||
{
|
||
/* Bitfields are not addressable. If the field bitsize is
|
||
zero, then the field is not packed. Hence it cannot be
|
||
a bitfield or any other packed type. */
|
||
if (TYPE_FIELD_BITSIZE (type, i) == 0)
|
||
{
|
||
nRc = 1;
|
||
break;
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
return nRc;
|
||
}
|
||
|
||
/* Write into appropriate registers a function return value of type
|
||
TYPE, given in virtual format. */
|
||
|
||
static void
|
||
arm_store_return_value (struct type *type, struct regcache *regs,
|
||
const gdb_byte *valbuf)
|
||
{
|
||
if (TYPE_CODE (type) == TYPE_CODE_FLT)
|
||
{
|
||
char buf[MAX_REGISTER_SIZE];
|
||
|
||
switch (gdbarch_tdep (current_gdbarch)->fp_model)
|
||
{
|
||
case ARM_FLOAT_FPA:
|
||
|
||
convert_to_extended (floatformat_from_type (type), buf, valbuf);
|
||
regcache_cooked_write (regs, ARM_F0_REGNUM, buf);
|
||
break;
|
||
|
||
case ARM_FLOAT_SOFT_FPA:
|
||
case ARM_FLOAT_SOFT_VFP:
|
||
regcache_cooked_write (regs, ARM_A1_REGNUM, valbuf);
|
||
if (TYPE_LENGTH (type) > 4)
|
||
regcache_cooked_write (regs, ARM_A1_REGNUM + 1,
|
||
valbuf + INT_REGISTER_SIZE);
|
||
break;
|
||
|
||
default:
|
||
internal_error
|
||
(__FILE__, __LINE__,
|
||
_("arm_store_return_value: Floating point model not supported"));
|
||
break;
|
||
}
|
||
}
|
||
else if (TYPE_CODE (type) == TYPE_CODE_INT
|
||
|| TYPE_CODE (type) == TYPE_CODE_CHAR
|
||
|| TYPE_CODE (type) == TYPE_CODE_BOOL
|
||
|| TYPE_CODE (type) == TYPE_CODE_PTR
|
||
|| TYPE_CODE (type) == TYPE_CODE_REF
|
||
|| TYPE_CODE (type) == TYPE_CODE_ENUM)
|
||
{
|
||
if (TYPE_LENGTH (type) <= 4)
|
||
{
|
||
/* Values of one word or less are zero/sign-extended and
|
||
returned in r0. */
|
||
bfd_byte tmpbuf[INT_REGISTER_SIZE];
|
||
LONGEST val = unpack_long (type, valbuf);
|
||
|
||
store_signed_integer (tmpbuf, INT_REGISTER_SIZE, val);
|
||
regcache_cooked_write (regs, ARM_A1_REGNUM, tmpbuf);
|
||
}
|
||
else
|
||
{
|
||
/* Integral values greater than one word are stored in consecutive
|
||
registers starting with r0. This will always be a multiple of
|
||
the regiser size. */
|
||
int len = TYPE_LENGTH (type);
|
||
int regno = ARM_A1_REGNUM;
|
||
|
||
while (len > 0)
|
||
{
|
||
regcache_cooked_write (regs, regno++, valbuf);
|
||
len -= INT_REGISTER_SIZE;
|
||
valbuf += INT_REGISTER_SIZE;
|
||
}
|
||
}
|
||
}
|
||
else
|
||
{
|
||
/* For a structure or union the behaviour is as if the value had
|
||
been stored to word-aligned memory and then loaded into
|
||
registers with 32-bit load instruction(s). */
|
||
int len = TYPE_LENGTH (type);
|
||
int regno = ARM_A1_REGNUM;
|
||
bfd_byte tmpbuf[INT_REGISTER_SIZE];
|
||
|
||
while (len > 0)
|
||
{
|
||
memcpy (tmpbuf, valbuf,
|
||
len > INT_REGISTER_SIZE ? INT_REGISTER_SIZE : len);
|
||
regcache_cooked_write (regs, regno++, tmpbuf);
|
||
len -= INT_REGISTER_SIZE;
|
||
valbuf += INT_REGISTER_SIZE;
|
||
}
|
||
}
|
||
}
|
||
|
||
|
||
/* Handle function return values. */
|
||
|
||
static enum return_value_convention
|
||
arm_return_value (struct gdbarch *gdbarch, struct type *valtype,
|
||
struct regcache *regcache, gdb_byte *readbuf,
|
||
const gdb_byte *writebuf)
|
||
{
|
||
if (TYPE_CODE (valtype) == TYPE_CODE_STRUCT
|
||
|| TYPE_CODE (valtype) == TYPE_CODE_UNION
|
||
|| TYPE_CODE (valtype) == TYPE_CODE_ARRAY)
|
||
{
|
||
if (arm_return_in_memory (gdbarch, valtype))
|
||
return RETURN_VALUE_STRUCT_CONVENTION;
|
||
}
|
||
|
||
if (writebuf)
|
||
arm_store_return_value (valtype, regcache, writebuf);
|
||
|
||
if (readbuf)
|
||
arm_extract_return_value (valtype, regcache, readbuf);
|
||
|
||
return RETURN_VALUE_REGISTER_CONVENTION;
|
||
}
|
||
|
||
|
||
static int
|
||
arm_get_longjmp_target (CORE_ADDR *pc)
|
||
{
|
||
CORE_ADDR jb_addr;
|
||
char buf[INT_REGISTER_SIZE];
|
||
struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
|
||
|
||
jb_addr = read_register (ARM_A1_REGNUM);
|
||
|
||
if (target_read_memory (jb_addr + tdep->jb_pc * tdep->jb_elt_size, buf,
|
||
INT_REGISTER_SIZE))
|
||
return 0;
|
||
|
||
*pc = extract_unsigned_integer (buf, INT_REGISTER_SIZE);
|
||
return 1;
|
||
}
|
||
|
||
/* Return non-zero if the PC is inside a thumb call thunk. */
|
||
|
||
int
|
||
arm_in_call_stub (CORE_ADDR pc, char *name)
|
||
{
|
||
CORE_ADDR start_addr;
|
||
|
||
/* Find the starting address of the function containing the PC. If
|
||
the caller didn't give us a name, look it up at the same time. */
|
||
if (0 == find_pc_partial_function (pc, name ? NULL : &name,
|
||
&start_addr, NULL))
|
||
return 0;
|
||
|
||
return strncmp (name, "_call_via_r", 11) == 0;
|
||
}
|
||
|
||
/* If PC is in a Thumb call or return stub, return the address of the
|
||
target PC, which is in a register. The thunk functions are called
|
||
_called_via_xx, where x is the register name. The possible names
|
||
are r0-r9, sl, fp, ip, sp, and lr. */
|
||
|
||
CORE_ADDR
|
||
arm_skip_stub (CORE_ADDR pc)
|
||
{
|
||
char *name;
|
||
CORE_ADDR start_addr;
|
||
|
||
/* Find the starting address and name of the function containing the PC. */
|
||
if (find_pc_partial_function (pc, &name, &start_addr, NULL) == 0)
|
||
return 0;
|
||
|
||
/* Call thunks always start with "_call_via_". */
|
||
if (strncmp (name, "_call_via_", 10) == 0)
|
||
{
|
||
/* Use the name suffix to determine which register contains the
|
||
target PC. */
|
||
static char *table[15] =
|
||
{"r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7",
|
||
"r8", "r9", "sl", "fp", "ip", "sp", "lr"
|
||
};
|
||
int regno;
|
||
|
||
for (regno = 0; regno <= 14; regno++)
|
||
if (strcmp (&name[10], table[regno]) == 0)
|
||
return read_register (regno);
|
||
}
|
||
|
||
return 0; /* not a stub */
|
||
}
|
||
|
||
static void
|
||
set_arm_command (char *args, int from_tty)
|
||
{
|
||
printf_unfiltered (_("\
|
||
\"set arm\" must be followed by an apporpriate subcommand.\n"));
|
||
help_list (setarmcmdlist, "set arm ", all_commands, gdb_stdout);
|
||
}
|
||
|
||
static void
|
||
show_arm_command (char *args, int from_tty)
|
||
{
|
||
cmd_show_list (showarmcmdlist, from_tty, "");
|
||
}
|
||
|
||
static void
|
||
arm_update_current_architecture (void)
|
||
{
|
||
struct gdbarch_info info;
|
||
|
||
/* If the current architecture is not ARM, we have nothing to do. */
|
||
if (gdbarch_bfd_arch_info (current_gdbarch)->arch != bfd_arch_arm)
|
||
return;
|
||
|
||
/* Update the architecture. */
|
||
gdbarch_info_init (&info);
|
||
|
||
if (!gdbarch_update_p (info))
|
||
internal_error (__FILE__, __LINE__, "could not update architecture");
|
||
}
|
||
|
||
static void
|
||
set_fp_model_sfunc (char *args, int from_tty,
|
||
struct cmd_list_element *c)
|
||
{
|
||
enum arm_float_model fp_model;
|
||
|
||
for (fp_model = ARM_FLOAT_AUTO; fp_model != ARM_FLOAT_LAST; fp_model++)
|
||
if (strcmp (current_fp_model, fp_model_strings[fp_model]) == 0)
|
||
{
|
||
arm_fp_model = fp_model;
|
||
break;
|
||
}
|
||
|
||
if (fp_model == ARM_FLOAT_LAST)
|
||
internal_error (__FILE__, __LINE__, _("Invalid fp model accepted: %s."),
|
||
current_fp_model);
|
||
|
||
arm_update_current_architecture ();
|
||
}
|
||
|
||
static void
|
||
show_fp_model (struct ui_file *file, int from_tty,
|
||
struct cmd_list_element *c, const char *value)
|
||
{
|
||
struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
|
||
|
||
if (arm_fp_model == ARM_FLOAT_AUTO
|
||
&& gdbarch_bfd_arch_info (current_gdbarch)->arch == bfd_arch_arm)
|
||
fprintf_filtered (file, _("\
|
||
The current ARM floating point model is \"auto\" (currently \"%s\").\n"),
|
||
fp_model_strings[tdep->fp_model]);
|
||
else
|
||
fprintf_filtered (file, _("\
|
||
The current ARM floating point model is \"%s\".\n"),
|
||
fp_model_strings[arm_fp_model]);
|
||
}
|
||
|
||
static void
|
||
arm_set_abi (char *args, int from_tty,
|
||
struct cmd_list_element *c)
|
||
{
|
||
enum arm_abi_kind arm_abi;
|
||
|
||
for (arm_abi = ARM_ABI_AUTO; arm_abi != ARM_ABI_LAST; arm_abi++)
|
||
if (strcmp (arm_abi_string, arm_abi_strings[arm_abi]) == 0)
|
||
{
|
||
arm_abi_global = arm_abi;
|
||
break;
|
||
}
|
||
|
||
if (arm_abi == ARM_ABI_LAST)
|
||
internal_error (__FILE__, __LINE__, _("Invalid ABI accepted: %s."),
|
||
arm_abi_string);
|
||
|
||
arm_update_current_architecture ();
|
||
}
|
||
|
||
static void
|
||
arm_show_abi (struct ui_file *file, int from_tty,
|
||
struct cmd_list_element *c, const char *value)
|
||
{
|
||
struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
|
||
|
||
if (arm_abi_global == ARM_ABI_AUTO
|
||
&& gdbarch_bfd_arch_info (current_gdbarch)->arch == bfd_arch_arm)
|
||
fprintf_filtered (file, _("\
|
||
The current ARM ABI is \"auto\" (currently \"%s\").\n"),
|
||
arm_abi_strings[tdep->arm_abi]);
|
||
else
|
||
fprintf_filtered (file, _("The current ARM ABI is \"%s\".\n"),
|
||
arm_abi_string);
|
||
}
|
||
|
||
/* If the user changes the register disassembly style used for info
|
||
register and other commands, we have to also switch the style used
|
||
in opcodes for disassembly output. This function is run in the "set
|
||
arm disassembly" command, and does that. */
|
||
|
||
static void
|
||
set_disassembly_style_sfunc (char *args, int from_tty,
|
||
struct cmd_list_element *c)
|
||
{
|
||
set_disassembly_style ();
|
||
}
|
||
|
||
/* Return the ARM register name corresponding to register I. */
|
||
static const char *
|
||
arm_register_name (int i)
|
||
{
|
||
return arm_register_names[i];
|
||
}
|
||
|
||
static void
|
||
set_disassembly_style (void)
|
||
{
|
||
const char *setname, *setdesc, *const *regnames;
|
||
int numregs, j;
|
||
|
||
/* Find the style that the user wants in the opcodes table. */
|
||
int current = 0;
|
||
numregs = get_arm_regnames (current, &setname, &setdesc, ®names);
|
||
while ((disassembly_style != setname)
|
||
&& (current < num_disassembly_options))
|
||
get_arm_regnames (++current, &setname, &setdesc, ®names);
|
||
current_option = current;
|
||
|
||
/* Fill our copy. */
|
||
for (j = 0; j < numregs; j++)
|
||
arm_register_names[j] = (char *) regnames[j];
|
||
|
||
/* Adjust case. */
|
||
if (isupper (*regnames[ARM_PC_REGNUM]))
|
||
{
|
||
arm_register_names[ARM_FPS_REGNUM] = "FPS";
|
||
arm_register_names[ARM_PS_REGNUM] = "CPSR";
|
||
}
|
||
else
|
||
{
|
||
arm_register_names[ARM_FPS_REGNUM] = "fps";
|
||
arm_register_names[ARM_PS_REGNUM] = "cpsr";
|
||
}
|
||
|
||
/* Synchronize the disassembler. */
|
||
set_arm_regname_option (current);
|
||
}
|
||
|
||
/* Test whether the coff symbol specific value corresponds to a Thumb
|
||
function. */
|
||
|
||
static int
|
||
coff_sym_is_thumb (int val)
|
||
{
|
||
return (val == C_THUMBEXT ||
|
||
val == C_THUMBSTAT ||
|
||
val == C_THUMBEXTFUNC ||
|
||
val == C_THUMBSTATFUNC ||
|
||
val == C_THUMBLABEL);
|
||
}
|
||
|
||
/* arm_coff_make_msymbol_special()
|
||
arm_elf_make_msymbol_special()
|
||
|
||
These functions test whether the COFF or ELF symbol corresponds to
|
||
an address in thumb code, and set a "special" bit in a minimal
|
||
symbol to indicate that it does. */
|
||
|
||
static void
|
||
arm_elf_make_msymbol_special(asymbol *sym, struct minimal_symbol *msym)
|
||
{
|
||
/* Thumb symbols are of type STT_LOPROC, (synonymous with
|
||
STT_ARM_TFUNC). */
|
||
if (ELF_ST_TYPE (((elf_symbol_type *)sym)->internal_elf_sym.st_info)
|
||
== STT_LOPROC)
|
||
MSYMBOL_SET_SPECIAL (msym);
|
||
}
|
||
|
||
static void
|
||
arm_coff_make_msymbol_special(int val, struct minimal_symbol *msym)
|
||
{
|
||
if (coff_sym_is_thumb (val))
|
||
MSYMBOL_SET_SPECIAL (msym);
|
||
}
|
||
|
||
static void
|
||
arm_write_pc (CORE_ADDR pc, ptid_t ptid)
|
||
{
|
||
write_register_pid (ARM_PC_REGNUM, pc, ptid);
|
||
|
||
/* If necessary, set the T bit. */
|
||
if (arm_apcs_32)
|
||
{
|
||
CORE_ADDR val = read_register_pid (ARM_PS_REGNUM, ptid);
|
||
if (arm_pc_is_thumb (pc))
|
||
write_register_pid (ARM_PS_REGNUM, val | 0x20, ptid);
|
||
else
|
||
write_register_pid (ARM_PS_REGNUM, val & ~(CORE_ADDR) 0x20, ptid);
|
||
}
|
||
}
|
||
|
||
static enum gdb_osabi
|
||
arm_elf_osabi_sniffer (bfd *abfd)
|
||
{
|
||
unsigned int elfosabi;
|
||
enum gdb_osabi osabi = GDB_OSABI_UNKNOWN;
|
||
|
||
elfosabi = elf_elfheader (abfd)->e_ident[EI_OSABI];
|
||
|
||
if (elfosabi == ELFOSABI_ARM)
|
||
/* GNU tools use this value. Check note sections in this case,
|
||
as well. */
|
||
bfd_map_over_sections (abfd,
|
||
generic_elf_osabi_sniff_abi_tag_sections,
|
||
&osabi);
|
||
|
||
/* Anything else will be handled by the generic ELF sniffer. */
|
||
return osabi;
|
||
}
|
||
|
||
|
||
/* Initialize the current architecture based on INFO. If possible,
|
||
re-use an architecture from ARCHES, which is a list of
|
||
architectures already created during this debugging session.
|
||
|
||
Called e.g. at program startup, when reading a core file, and when
|
||
reading a binary file. */
|
||
|
||
static struct gdbarch *
|
||
arm_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
|
||
{
|
||
struct gdbarch_tdep *tdep;
|
||
struct gdbarch *gdbarch;
|
||
struct gdbarch_list *best_arch;
|
||
enum arm_abi_kind arm_abi = arm_abi_global;
|
||
enum arm_float_model fp_model = arm_fp_model;
|
||
|
||
/* If we have an object to base this architecture on, try to determine
|
||
its ABI. */
|
||
|
||
if (arm_abi == ARM_ABI_AUTO && info.abfd != NULL)
|
||
{
|
||
int ei_osabi;
|
||
|
||
switch (bfd_get_flavour (info.abfd))
|
||
{
|
||
case bfd_target_aout_flavour:
|
||
/* Assume it's an old APCS-style ABI. */
|
||
arm_abi = ARM_ABI_APCS;
|
||
break;
|
||
|
||
case bfd_target_coff_flavour:
|
||
/* Assume it's an old APCS-style ABI. */
|
||
/* XXX WinCE? */
|
||
arm_abi = ARM_ABI_APCS;
|
||
break;
|
||
|
||
case bfd_target_elf_flavour:
|
||
ei_osabi = elf_elfheader (info.abfd)->e_ident[EI_OSABI];
|
||
if (ei_osabi == ELFOSABI_ARM)
|
||
{
|
||
/* GNU tools used to use this value, but do not for EABI
|
||
objects. There's nowhere to tag an EABI version anyway,
|
||
so assume APCS. */
|
||
arm_abi = ARM_ABI_APCS;
|
||
}
|
||
else if (ei_osabi == ELFOSABI_NONE)
|
||
{
|
||
int e_flags, eabi_ver;
|
||
|
||
e_flags = elf_elfheader (info.abfd)->e_flags;
|
||
eabi_ver = EF_ARM_EABI_VERSION (e_flags);
|
||
|
||
switch (eabi_ver)
|
||
{
|
||
case EF_ARM_EABI_UNKNOWN:
|
||
/* Assume GNU tools. */
|
||
arm_abi = ARM_ABI_APCS;
|
||
break;
|
||
|
||
case EF_ARM_EABI_VER4:
|
||
arm_abi = ARM_ABI_AAPCS;
|
||
/* EABI binaries default to VFP float ordering. */
|
||
if (fp_model == ARM_FLOAT_AUTO)
|
||
fp_model = ARM_FLOAT_SOFT_VFP;
|
||
break;
|
||
|
||
default:
|
||
warning (_("unknown ARM EABI version 0x%x"), eabi_ver);
|
||
arm_abi = ARM_ABI_APCS;
|
||
break;
|
||
}
|
||
}
|
||
break;
|
||
|
||
default:
|
||
/* Leave it as "auto". */
|
||
break;
|
||
}
|
||
}
|
||
|
||
/* Now that we have inferred any architecture settings that we
|
||
can, try to inherit from the last ARM ABI. */
|
||
if (arches != NULL)
|
||
{
|
||
if (arm_abi == ARM_ABI_AUTO)
|
||
arm_abi = gdbarch_tdep (arches->gdbarch)->arm_abi;
|
||
|
||
if (fp_model == ARM_FLOAT_AUTO)
|
||
fp_model = gdbarch_tdep (arches->gdbarch)->fp_model;
|
||
}
|
||
else
|
||
{
|
||
/* There was no prior ARM architecture; fill in default values. */
|
||
|
||
if (arm_abi == ARM_ABI_AUTO)
|
||
arm_abi = ARM_ABI_APCS;
|
||
|
||
/* We used to default to FPA for generic ARM, but almost nobody
|
||
uses that now, and we now provide a way for the user to force
|
||
the model. So default to the most useful variant. */
|
||
if (fp_model == ARM_FLOAT_AUTO)
|
||
fp_model = ARM_FLOAT_SOFT_FPA;
|
||
}
|
||
|
||
/* If there is already a candidate, use it. */
|
||
for (best_arch = gdbarch_list_lookup_by_info (arches, &info);
|
||
best_arch != NULL;
|
||
best_arch = gdbarch_list_lookup_by_info (best_arch->next, &info))
|
||
{
|
||
if (arm_abi != gdbarch_tdep (best_arch->gdbarch)->arm_abi)
|
||
continue;
|
||
|
||
if (fp_model != gdbarch_tdep (best_arch->gdbarch)->fp_model)
|
||
continue;
|
||
|
||
/* Found a match. */
|
||
break;
|
||
}
|
||
|
||
if (best_arch != NULL)
|
||
return best_arch->gdbarch;
|
||
|
||
tdep = xcalloc (1, sizeof (struct gdbarch_tdep));
|
||
gdbarch = gdbarch_alloc (&info, tdep);
|
||
|
||
/* Record additional information about the architecture we are defining.
|
||
These are gdbarch discriminators, like the OSABI. */
|
||
tdep->arm_abi = arm_abi;
|
||
tdep->fp_model = fp_model;
|
||
|
||
/* Breakpoints. */
|
||
switch (info.byte_order)
|
||
{
|
||
case BFD_ENDIAN_BIG:
|
||
tdep->arm_breakpoint = arm_default_arm_be_breakpoint;
|
||
tdep->arm_breakpoint_size = sizeof (arm_default_arm_be_breakpoint);
|
||
tdep->thumb_breakpoint = arm_default_thumb_be_breakpoint;
|
||
tdep->thumb_breakpoint_size = sizeof (arm_default_thumb_be_breakpoint);
|
||
|
||
break;
|
||
|
||
case BFD_ENDIAN_LITTLE:
|
||
tdep->arm_breakpoint = arm_default_arm_le_breakpoint;
|
||
tdep->arm_breakpoint_size = sizeof (arm_default_arm_le_breakpoint);
|
||
tdep->thumb_breakpoint = arm_default_thumb_le_breakpoint;
|
||
tdep->thumb_breakpoint_size = sizeof (arm_default_thumb_le_breakpoint);
|
||
|
||
break;
|
||
|
||
default:
|
||
internal_error (__FILE__, __LINE__,
|
||
_("arm_gdbarch_init: bad byte order for float format"));
|
||
}
|
||
|
||
/* On ARM targets char defaults to unsigned. */
|
||
set_gdbarch_char_signed (gdbarch, 0);
|
||
|
||
/* This should be low enough for everything. */
|
||
tdep->lowest_pc = 0x20;
|
||
tdep->jb_pc = -1; /* Longjump support not enabled by default. */
|
||
|
||
set_gdbarch_push_dummy_call (gdbarch, arm_push_dummy_call);
|
||
set_gdbarch_frame_align (gdbarch, arm_frame_align);
|
||
|
||
set_gdbarch_write_pc (gdbarch, arm_write_pc);
|
||
|
||
/* Frame handling. */
|
||
set_gdbarch_unwind_dummy_id (gdbarch, arm_unwind_dummy_id);
|
||
set_gdbarch_unwind_pc (gdbarch, arm_unwind_pc);
|
||
set_gdbarch_unwind_sp (gdbarch, arm_unwind_sp);
|
||
|
||
frame_base_set_default (gdbarch, &arm_normal_base);
|
||
|
||
/* Address manipulation. */
|
||
set_gdbarch_smash_text_address (gdbarch, arm_smash_text_address);
|
||
set_gdbarch_addr_bits_remove (gdbarch, arm_addr_bits_remove);
|
||
|
||
/* Advance PC across function entry code. */
|
||
set_gdbarch_skip_prologue (gdbarch, arm_skip_prologue);
|
||
|
||
/* Get the PC when a frame might not be available. */
|
||
set_gdbarch_deprecated_saved_pc_after_call (gdbarch, arm_saved_pc_after_call);
|
||
|
||
/* The stack grows downward. */
|
||
set_gdbarch_inner_than (gdbarch, core_addr_lessthan);
|
||
|
||
/* Breakpoint manipulation. */
|
||
set_gdbarch_breakpoint_from_pc (gdbarch, arm_breakpoint_from_pc);
|
||
|
||
/* Information about registers, etc. */
|
||
set_gdbarch_print_float_info (gdbarch, arm_print_float_info);
|
||
set_gdbarch_deprecated_fp_regnum (gdbarch, ARM_FP_REGNUM); /* ??? */
|
||
set_gdbarch_sp_regnum (gdbarch, ARM_SP_REGNUM);
|
||
set_gdbarch_pc_regnum (gdbarch, ARM_PC_REGNUM);
|
||
set_gdbarch_deprecated_register_byte (gdbarch, arm_register_byte);
|
||
set_gdbarch_num_regs (gdbarch, NUM_GREGS + NUM_FREGS + NUM_SREGS);
|
||
set_gdbarch_register_type (gdbarch, arm_register_type);
|
||
|
||
/* Internal <-> external register number maps. */
|
||
set_gdbarch_register_sim_regno (gdbarch, arm_register_sim_regno);
|
||
|
||
/* Integer registers are 4 bytes. */
|
||
set_gdbarch_deprecated_register_size (gdbarch, 4);
|
||
set_gdbarch_register_name (gdbarch, arm_register_name);
|
||
|
||
/* Returning results. */
|
||
set_gdbarch_return_value (gdbarch, arm_return_value);
|
||
|
||
/* Single stepping. */
|
||
/* XXX For an RDI target we should ask the target if it can single-step. */
|
||
set_gdbarch_software_single_step (gdbarch, arm_software_single_step);
|
||
|
||
/* Disassembly. */
|
||
set_gdbarch_print_insn (gdbarch, gdb_print_insn_arm);
|
||
|
||
/* Minsymbol frobbing. */
|
||
set_gdbarch_elf_make_msymbol_special (gdbarch, arm_elf_make_msymbol_special);
|
||
set_gdbarch_coff_make_msymbol_special (gdbarch,
|
||
arm_coff_make_msymbol_special);
|
||
|
||
/* Hook in the ABI-specific overrides, if they have been registered. */
|
||
gdbarch_init_osabi (info, gdbarch);
|
||
|
||
/* Add some default predicates. */
|
||
frame_unwind_append_sniffer (gdbarch, arm_stub_unwind_sniffer);
|
||
frame_unwind_append_sniffer (gdbarch, dwarf2_frame_sniffer);
|
||
frame_unwind_append_sniffer (gdbarch, arm_prologue_unwind_sniffer);
|
||
|
||
/* Now we have tuned the configuration, set a few final things,
|
||
based on what the OS ABI has told us. */
|
||
|
||
if (tdep->jb_pc >= 0)
|
||
set_gdbarch_get_longjmp_target (gdbarch, arm_get_longjmp_target);
|
||
|
||
/* Floating point sizes and format. */
|
||
switch (info.byte_order)
|
||
{
|
||
case BFD_ENDIAN_BIG:
|
||
set_gdbarch_float_format (gdbarch, &floatformat_ieee_single_big);
|
||
set_gdbarch_double_format (gdbarch, &floatformat_ieee_double_big);
|
||
set_gdbarch_long_double_format (gdbarch, &floatformat_ieee_double_big);
|
||
break;
|
||
|
||
case BFD_ENDIAN_LITTLE:
|
||
set_gdbarch_float_format (gdbarch, &floatformat_ieee_single_little);
|
||
if (fp_model == ARM_FLOAT_SOFT_FPA || fp_model == ARM_FLOAT_FPA)
|
||
{
|
||
set_gdbarch_double_format
|
||
(gdbarch, &floatformat_ieee_double_littlebyte_bigword);
|
||
set_gdbarch_long_double_format
|
||
(gdbarch, &floatformat_ieee_double_littlebyte_bigword);
|
||
}
|
||
else
|
||
{
|
||
set_gdbarch_double_format (gdbarch, &floatformat_ieee_double_little);
|
||
set_gdbarch_long_double_format (gdbarch,
|
||
&floatformat_ieee_double_little);
|
||
}
|
||
break;
|
||
|
||
default:
|
||
internal_error (__FILE__, __LINE__,
|
||
_("arm_gdbarch_init: bad byte order for float format"));
|
||
}
|
||
|
||
return gdbarch;
|
||
}
|
||
|
||
static void
|
||
arm_dump_tdep (struct gdbarch *current_gdbarch, struct ui_file *file)
|
||
{
|
||
struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
|
||
|
||
if (tdep == NULL)
|
||
return;
|
||
|
||
fprintf_unfiltered (file, _("arm_dump_tdep: Lowest pc = 0x%lx"),
|
||
(unsigned long) tdep->lowest_pc);
|
||
}
|
||
|
||
extern initialize_file_ftype _initialize_arm_tdep; /* -Wmissing-prototypes */
|
||
|
||
void
|
||
_initialize_arm_tdep (void)
|
||
{
|
||
struct ui_file *stb;
|
||
long length;
|
||
struct cmd_list_element *new_set, *new_show;
|
||
const char *setname;
|
||
const char *setdesc;
|
||
const char *const *regnames;
|
||
int numregs, i, j;
|
||
static char *helptext;
|
||
char regdesc[1024], *rdptr = regdesc;
|
||
size_t rest = sizeof (regdesc);
|
||
|
||
gdbarch_register (bfd_arch_arm, arm_gdbarch_init, arm_dump_tdep);
|
||
|
||
/* Register an ELF OS ABI sniffer for ARM binaries. */
|
||
gdbarch_register_osabi_sniffer (bfd_arch_arm,
|
||
bfd_target_elf_flavour,
|
||
arm_elf_osabi_sniffer);
|
||
|
||
/* Get the number of possible sets of register names defined in opcodes. */
|
||
num_disassembly_options = get_arm_regname_num_options ();
|
||
|
||
/* Add root prefix command for all "set arm"/"show arm" commands. */
|
||
add_prefix_cmd ("arm", no_class, set_arm_command,
|
||
_("Various ARM-specific commands."),
|
||
&setarmcmdlist, "set arm ", 0, &setlist);
|
||
|
||
add_prefix_cmd ("arm", no_class, show_arm_command,
|
||
_("Various ARM-specific commands."),
|
||
&showarmcmdlist, "show arm ", 0, &showlist);
|
||
|
||
/* Sync the opcode insn printer with our register viewer. */
|
||
parse_arm_disassembler_option ("reg-names-std");
|
||
|
||
/* Initialize the array that will be passed to
|
||
add_setshow_enum_cmd(). */
|
||
valid_disassembly_styles
|
||
= xmalloc ((num_disassembly_options + 1) * sizeof (char *));
|
||
for (i = 0; i < num_disassembly_options; i++)
|
||
{
|
||
numregs = get_arm_regnames (i, &setname, &setdesc, ®names);
|
||
valid_disassembly_styles[i] = setname;
|
||
length = snprintf (rdptr, rest, "%s - %s\n", setname, setdesc);
|
||
rdptr += length;
|
||
rest -= length;
|
||
/* Copy the default names (if found) and synchronize disassembler. */
|
||
if (!strcmp (setname, "std"))
|
||
{
|
||
disassembly_style = setname;
|
||
current_option = i;
|
||
for (j = 0; j < numregs; j++)
|
||
arm_register_names[j] = (char *) regnames[j];
|
||
set_arm_regname_option (i);
|
||
}
|
||
}
|
||
/* Mark the end of valid options. */
|
||
valid_disassembly_styles[num_disassembly_options] = NULL;
|
||
|
||
/* Create the help text. */
|
||
stb = mem_fileopen ();
|
||
fprintf_unfiltered (stb, "%s%s%s",
|
||
_("The valid values are:\n"),
|
||
regdesc,
|
||
_("The default is \"std\"."));
|
||
helptext = ui_file_xstrdup (stb, &length);
|
||
ui_file_delete (stb);
|
||
|
||
add_setshow_enum_cmd("disassembler", no_class,
|
||
valid_disassembly_styles, &disassembly_style,
|
||
_("Set the disassembly style."),
|
||
_("Show the disassembly style."),
|
||
helptext,
|
||
set_disassembly_style_sfunc,
|
||
NULL, /* FIXME: i18n: The disassembly style is \"%s\". */
|
||
&setarmcmdlist, &showarmcmdlist);
|
||
|
||
add_setshow_boolean_cmd ("apcs32", no_class, &arm_apcs_32,
|
||
_("Set usage of ARM 32-bit mode."),
|
||
_("Show usage of ARM 32-bit mode."),
|
||
_("When off, a 26-bit PC will be used."),
|
||
NULL,
|
||
NULL, /* FIXME: i18n: Usage of ARM 32-bit mode is %s. */
|
||
&setarmcmdlist, &showarmcmdlist);
|
||
|
||
/* Add a command to allow the user to force the FPU model. */
|
||
add_setshow_enum_cmd ("fpu", no_class, fp_model_strings, ¤t_fp_model,
|
||
_("Set the floating point type."),
|
||
_("Show the floating point type."),
|
||
_("auto - Determine the FP typefrom the OS-ABI.\n\
|
||
softfpa - Software FP, mixed-endian doubles on little-endian ARMs.\n\
|
||
fpa - FPA co-processor (GCC compiled).\n\
|
||
softvfp - Software FP with pure-endian doubles.\n\
|
||
vfp - VFP co-processor."),
|
||
set_fp_model_sfunc, show_fp_model,
|
||
&setarmcmdlist, &showarmcmdlist);
|
||
|
||
/* Add a command to allow the user to force the ABI. */
|
||
add_setshow_enum_cmd ("abi", class_support, arm_abi_strings, &arm_abi_string,
|
||
_("Set the ABI."),
|
||
_("Show the ABI."),
|
||
NULL, arm_set_abi, arm_show_abi,
|
||
&setarmcmdlist, &showarmcmdlist);
|
||
|
||
/* Debugging flag. */
|
||
add_setshow_boolean_cmd ("arm", class_maintenance, &arm_debug,
|
||
_("Set ARM debugging."),
|
||
_("Show ARM debugging."),
|
||
_("When on, arm-specific debugging is enabled."),
|
||
NULL,
|
||
NULL, /* FIXME: i18n: "ARM debugging is %s. */
|
||
&setdebuglist, &showdebuglist);
|
||
}
|