1550 lines
47 KiB
C
1550 lines
47 KiB
C
/* Target-dependent code for Atmel AVR, for GDB.
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Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
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2006, 2007, 2008, 2009, 2010 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 3 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, see <http://www.gnu.org/licenses/>. */
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/* Contributed by Theodore A. Roth, troth@openavr.org */
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/* Portions of this file were taken from the original gdb-4.18 patch developed
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by Denis Chertykov, denisc@overta.ru */
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#include "defs.h"
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#include "frame.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 "gdbcmd.h"
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#include "gdbcore.h"
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#include "gdbtypes.h"
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#include "inferior.h"
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#include "symfile.h"
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#include "arch-utils.h"
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#include "regcache.h"
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#include "gdb_string.h"
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#include "dis-asm.h"
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/* AVR Background:
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(AVR micros are pure Harvard Architecture processors.)
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The AVR family of microcontrollers have three distinctly different memory
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spaces: flash, sram and eeprom. The flash is 16 bits wide and is used for
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the most part to store program instructions. The sram is 8 bits wide and is
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used for the stack and the heap. Some devices lack sram and some can have
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an additional external sram added on as a peripheral.
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The eeprom is 8 bits wide and is used to store data when the device is
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powered down. Eeprom is not directly accessible, it can only be accessed
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via io-registers using a special algorithm. Accessing eeprom via gdb's
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remote serial protocol ('m' or 'M' packets) looks difficult to do and is
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not included at this time.
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[The eeprom could be read manually via ``x/b <eaddr + AVR_EMEM_START>'' or
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written using ``set {unsigned char}<eaddr + AVR_EMEM_START>''. For this to
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work, the remote target must be able to handle eeprom accesses and perform
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the address translation.]
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All three memory spaces have physical addresses beginning at 0x0. In
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addition, the flash is addressed by gcc/binutils/gdb with respect to 8 bit
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bytes instead of the 16 bit wide words used by the real device for the
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Program Counter.
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In order for remote targets to work correctly, extra bits must be added to
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addresses before they are send to the target or received from the target
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via the remote serial protocol. The extra bits are the MSBs and are used to
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decode which memory space the address is referring to. */
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#undef XMALLOC
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#define XMALLOC(TYPE) ((TYPE*) xmalloc (sizeof (TYPE)))
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/* Constants: prefixed with AVR_ to avoid name space clashes */
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enum
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{
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AVR_REG_W = 24,
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AVR_REG_X = 26,
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AVR_REG_Y = 28,
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AVR_FP_REGNUM = 28,
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AVR_REG_Z = 30,
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AVR_SREG_REGNUM = 32,
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AVR_SP_REGNUM = 33,
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AVR_PC_REGNUM = 34,
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AVR_NUM_REGS = 32 + 1 /*SREG*/ + 1 /*SP*/ + 1 /*PC*/,
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AVR_NUM_REG_BYTES = 32 + 1 /*SREG*/ + 2 /*SP*/ + 4 /*PC*/,
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/* Pseudo registers. */
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AVR_PSEUDO_PC_REGNUM = 35,
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AVR_NUM_PSEUDO_REGS = 1,
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AVR_PC_REG_INDEX = 35, /* index into array of registers */
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AVR_MAX_PROLOGUE_SIZE = 64, /* bytes */
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/* Count of pushed registers. From r2 to r17 (inclusively), r28, r29 */
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AVR_MAX_PUSHES = 18,
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/* Number of the last pushed register. r17 for current avr-gcc */
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AVR_LAST_PUSHED_REGNUM = 17,
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AVR_ARG1_REGNUM = 24, /* Single byte argument */
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AVR_ARGN_REGNUM = 25, /* Multi byte argments */
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AVR_RET1_REGNUM = 24, /* Single byte return value */
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AVR_RETN_REGNUM = 25, /* Multi byte return value */
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/* FIXME: TRoth/2002-01-??: Can we shift all these memory masks left 8
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bits? Do these have to match the bfd vma values?. It sure would make
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things easier in the future if they didn't need to match.
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Note: I chose these values so as to be consistent with bfd vma
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addresses.
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TRoth/2002-04-08: There is already a conflict with very large programs
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in the mega128. The mega128 has 128K instruction bytes (64K words),
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thus the Most Significant Bit is 0x10000 which gets masked off my
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AVR_MEM_MASK.
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The problem manifests itself when trying to set a breakpoint in a
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function which resides in the upper half of the instruction space and
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thus requires a 17-bit address.
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For now, I've just removed the EEPROM mask and changed AVR_MEM_MASK
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from 0x00ff0000 to 0x00f00000. Eeprom is not accessible from gdb yet,
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but could be for some remote targets by just adding the correct offset
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to the address and letting the remote target handle the low-level
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details of actually accessing the eeprom. */
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AVR_IMEM_START = 0x00000000, /* INSN memory */
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AVR_SMEM_START = 0x00800000, /* SRAM memory */
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#if 1
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/* No eeprom mask defined */
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AVR_MEM_MASK = 0x00f00000, /* mask to determine memory space */
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#else
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AVR_EMEM_START = 0x00810000, /* EEPROM memory */
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AVR_MEM_MASK = 0x00ff0000, /* mask to determine memory space */
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#endif
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};
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/* Prologue types:
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NORMAL and CALL are the typical types (the -mcall-prologues gcc option
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causes the generation of the CALL type prologues). */
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enum {
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AVR_PROLOGUE_NONE, /* No prologue */
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AVR_PROLOGUE_NORMAL,
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AVR_PROLOGUE_CALL, /* -mcall-prologues */
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AVR_PROLOGUE_MAIN,
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AVR_PROLOGUE_INTR, /* interrupt handler */
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AVR_PROLOGUE_SIG, /* signal handler */
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};
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/* Any function with a frame looks like this
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....... <-SP POINTS HERE
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LOCALS1 <-FP POINTS HERE
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LOCALS0
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SAVED FP
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SAVED R3
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SAVED R2
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RET PC
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FIRST ARG
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SECOND ARG */
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struct avr_unwind_cache
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{
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/* The previous frame's inner most stack address. Used as this
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frame ID's stack_addr. */
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CORE_ADDR prev_sp;
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/* The frame's base, optionally used by the high-level debug info. */
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CORE_ADDR base;
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int size;
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int prologue_type;
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/* Table indicating the location of each and every register. */
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struct trad_frame_saved_reg *saved_regs;
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};
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struct gdbarch_tdep
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{
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/* Number of bytes stored to the stack by call instructions.
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2 bytes for avr1-5, 3 bytes for avr6. */
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int call_length;
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/* Type for void. */
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struct type *void_type;
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/* Type for a function returning void. */
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struct type *func_void_type;
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/* Type for a pointer to a function. Used for the type of PC. */
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struct type *pc_type;
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};
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/* Lookup the name of a register given it's number. */
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static const char *
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avr_register_name (struct gdbarch *gdbarch, int regnum)
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{
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static const char * const register_names[] = {
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"r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7",
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"r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15",
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"r16", "r17", "r18", "r19", "r20", "r21", "r22", "r23",
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"r24", "r25", "r26", "r27", "r28", "r29", "r30", "r31",
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"SREG", "SP", "PC2",
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"pc"
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};
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if (regnum < 0)
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return NULL;
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if (regnum >= (sizeof (register_names) / sizeof (*register_names)))
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return NULL;
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return register_names[regnum];
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}
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/* Return the GDB type object for the "standard" data type
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of data in register N. */
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static struct type *
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avr_register_type (struct gdbarch *gdbarch, int reg_nr)
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{
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if (reg_nr == AVR_PC_REGNUM)
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return builtin_type (gdbarch)->builtin_uint32;
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if (reg_nr == AVR_PSEUDO_PC_REGNUM)
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return gdbarch_tdep (gdbarch)->pc_type;
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if (reg_nr == AVR_SP_REGNUM)
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return builtin_type (gdbarch)->builtin_data_ptr;
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return builtin_type (gdbarch)->builtin_uint8;
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}
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/* Instruction address checks and convertions. */
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static CORE_ADDR
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avr_make_iaddr (CORE_ADDR x)
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{
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return ((x) | AVR_IMEM_START);
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}
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/* FIXME: TRoth: Really need to use a larger mask for instructions. Some
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devices are already up to 128KBytes of flash space.
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TRoth/2002-04-8: See comment above where AVR_IMEM_START is defined. */
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static CORE_ADDR
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avr_convert_iaddr_to_raw (CORE_ADDR x)
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{
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return ((x) & 0xffffffff);
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}
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/* SRAM address checks and convertions. */
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static CORE_ADDR
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avr_make_saddr (CORE_ADDR x)
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{
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/* Return 0 for NULL. */
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if (x == 0)
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return 0;
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return ((x) | AVR_SMEM_START);
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}
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static CORE_ADDR
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avr_convert_saddr_to_raw (CORE_ADDR x)
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{
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return ((x) & 0xffffffff);
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}
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/* EEPROM address checks and convertions. I don't know if these will ever
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actually be used, but I've added them just the same. TRoth */
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/* TRoth/2002-04-08: Commented out for now to allow fix for problem with large
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programs in the mega128. */
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/* static CORE_ADDR */
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/* avr_make_eaddr (CORE_ADDR x) */
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/* { */
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/* return ((x) | AVR_EMEM_START); */
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/* } */
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/* static int */
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/* avr_eaddr_p (CORE_ADDR x) */
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/* { */
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/* return (((x) & AVR_MEM_MASK) == AVR_EMEM_START); */
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/* } */
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/* static CORE_ADDR */
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/* avr_convert_eaddr_to_raw (CORE_ADDR x) */
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/* { */
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/* return ((x) & 0xffffffff); */
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/* } */
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/* Convert from address to pointer and vice-versa. */
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static void
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avr_address_to_pointer (struct gdbarch *gdbarch,
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struct type *type, gdb_byte *buf, CORE_ADDR addr)
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{
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enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
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/* Is it a code address? */
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if (TYPE_CODE (TYPE_TARGET_TYPE (type)) == TYPE_CODE_FUNC
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|| TYPE_CODE (TYPE_TARGET_TYPE (type)) == TYPE_CODE_METHOD)
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{
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store_unsigned_integer (buf, TYPE_LENGTH (type), byte_order,
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avr_convert_iaddr_to_raw (addr >> 1));
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}
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else
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{
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/* Strip off any upper segment bits. */
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store_unsigned_integer (buf, TYPE_LENGTH (type), byte_order,
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avr_convert_saddr_to_raw (addr));
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}
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}
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static CORE_ADDR
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avr_pointer_to_address (struct gdbarch *gdbarch,
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struct type *type, const gdb_byte *buf)
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{
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enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
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CORE_ADDR addr
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= extract_unsigned_integer (buf, TYPE_LENGTH (type), byte_order);
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/* Is it a code address? */
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if (TYPE_CODE (TYPE_TARGET_TYPE (type)) == TYPE_CODE_FUNC
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|| TYPE_CODE (TYPE_TARGET_TYPE (type)) == TYPE_CODE_METHOD
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|| TYPE_CODE_SPACE (TYPE_TARGET_TYPE (type)))
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return avr_make_iaddr (addr << 1);
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else
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return avr_make_saddr (addr);
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}
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static CORE_ADDR
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avr_integer_to_address (struct gdbarch *gdbarch,
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struct type *type, const gdb_byte *buf)
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{
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ULONGEST addr = unpack_long (type, buf);
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return avr_make_saddr (addr);
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}
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static CORE_ADDR
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avr_read_pc (struct regcache *regcache)
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{
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ULONGEST pc;
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regcache_cooked_read_unsigned (regcache, AVR_PC_REGNUM, &pc);
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return avr_make_iaddr (pc);
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}
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static void
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avr_write_pc (struct regcache *regcache, CORE_ADDR val)
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{
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regcache_cooked_write_unsigned (regcache, AVR_PC_REGNUM,
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avr_convert_iaddr_to_raw (val));
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}
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static void
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avr_pseudo_register_read (struct gdbarch *gdbarch, struct regcache *regcache,
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int regnum, gdb_byte *buf)
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{
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ULONGEST val;
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switch (regnum)
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{
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case AVR_PSEUDO_PC_REGNUM:
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regcache_raw_read_unsigned (regcache, AVR_PC_REGNUM, &val);
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val >>= 1;
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store_unsigned_integer (buf, 4, gdbarch_byte_order (gdbarch), val);
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break;
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default:
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internal_error (__FILE__, __LINE__, _("invalid regnum"));
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}
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}
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static void
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avr_pseudo_register_write (struct gdbarch *gdbarch, struct regcache *regcache,
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int regnum, const gdb_byte *buf)
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{
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ULONGEST val;
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switch (regnum)
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{
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case AVR_PSEUDO_PC_REGNUM:
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val = extract_unsigned_integer (buf, 4, gdbarch_byte_order (gdbarch));
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val <<= 1;
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regcache_raw_write_unsigned (regcache, AVR_PC_REGNUM, val);
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break;
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default:
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internal_error (__FILE__, __LINE__, _("invalid regnum"));
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}
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}
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/* Function: avr_scan_prologue
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This function decodes an AVR function prologue to determine:
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1) the size of the stack frame
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2) which registers are saved on it
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3) the offsets of saved regs
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This information is stored in the avr_unwind_cache structure.
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Some devices lack the sbiw instruction, so on those replace this:
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sbiw r28, XX
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with this:
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subi r28,lo8(XX)
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sbci r29,hi8(XX)
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A typical AVR function prologue with a frame pointer might look like this:
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push rXX ; saved regs
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...
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push r28
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push r29
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in r28,__SP_L__
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in r29,__SP_H__
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sbiw r28,<LOCALS_SIZE>
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in __tmp_reg__,__SREG__
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cli
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out __SP_H__,r29
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out __SREG__,__tmp_reg__
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out __SP_L__,r28
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A typical AVR function prologue without a frame pointer might look like
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this:
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push rXX ; saved regs
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...
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A main function prologue looks like this:
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ldi r28,lo8(<RAM_ADDR> - <LOCALS_SIZE>)
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ldi r29,hi8(<RAM_ADDR> - <LOCALS_SIZE>)
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out __SP_H__,r29
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out __SP_L__,r28
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A signal handler prologue looks like this:
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push __zero_reg__
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push __tmp_reg__
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in __tmp_reg__, __SREG__
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push __tmp_reg__
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clr __zero_reg__
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push rXX ; save registers r18:r27, r30:r31
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...
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push r28 ; save frame pointer
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push r29
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in r28, __SP_L__
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in r29, __SP_H__
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sbiw r28, <LOCALS_SIZE>
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out __SP_H__, r29
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out __SP_L__, r28
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A interrupt handler prologue looks like this:
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sei
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push __zero_reg__
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push __tmp_reg__
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in __tmp_reg__, __SREG__
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push __tmp_reg__
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clr __zero_reg__
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push rXX ; save registers r18:r27, r30:r31
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...
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push r28 ; save frame pointer
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push r29
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in r28, __SP_L__
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in r29, __SP_H__
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sbiw r28, <LOCALS_SIZE>
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cli
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out __SP_H__, r29
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sei
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out __SP_L__, r28
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A `-mcall-prologues' prologue looks like this (Note that the megas use a
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jmp instead of a rjmp, thus the prologue is one word larger since jmp is a
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32 bit insn and rjmp is a 16 bit insn):
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ldi r26,lo8(<LOCALS_SIZE>)
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ldi r27,hi8(<LOCALS_SIZE>)
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ldi r30,pm_lo8(.L_foo_body)
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ldi r31,pm_hi8(.L_foo_body)
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rjmp __prologue_saves__+RRR
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.L_foo_body: */
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/* Not really part of a prologue, but still need to scan for it, is when a
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function prologue moves values passed via registers as arguments to new
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registers. In this case, all local variables live in registers, so there
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may be some register saves. This is what it looks like:
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movw rMM, rNN
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...
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There could be multiple movw's. If the target doesn't have a movw insn, it
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will use two mov insns. This could be done after any of the above prologue
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types. */
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static CORE_ADDR
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avr_scan_prologue (struct gdbarch *gdbarch, CORE_ADDR pc_beg, CORE_ADDR pc_end,
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struct avr_unwind_cache *info)
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{
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enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
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int i;
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unsigned short insn;
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int scan_stage = 0;
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struct minimal_symbol *msymbol;
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unsigned char prologue[AVR_MAX_PROLOGUE_SIZE];
|
|
int vpc = 0;
|
|
int len;
|
|
|
|
len = pc_end - pc_beg;
|
|
if (len > AVR_MAX_PROLOGUE_SIZE)
|
|
len = AVR_MAX_PROLOGUE_SIZE;
|
|
|
|
/* FIXME: TRoth/2003-06-11: This could be made more efficient by only
|
|
reading in the bytes of the prologue. The problem is that the figuring
|
|
out where the end of the prologue is is a bit difficult. The old code
|
|
tried to do that, but failed quite often. */
|
|
read_memory (pc_beg, prologue, len);
|
|
|
|
/* Scanning main()'s prologue
|
|
ldi r28,lo8(<RAM_ADDR> - <LOCALS_SIZE>)
|
|
ldi r29,hi8(<RAM_ADDR> - <LOCALS_SIZE>)
|
|
out __SP_H__,r29
|
|
out __SP_L__,r28 */
|
|
|
|
if (len >= 4)
|
|
{
|
|
CORE_ADDR locals;
|
|
static const unsigned char img[] = {
|
|
0xde, 0xbf, /* out __SP_H__,r29 */
|
|
0xcd, 0xbf /* out __SP_L__,r28 */
|
|
};
|
|
|
|
insn = extract_unsigned_integer (&prologue[vpc], 2, byte_order);
|
|
/* ldi r28,lo8(<RAM_ADDR> - <LOCALS_SIZE>) */
|
|
if ((insn & 0xf0f0) == 0xe0c0)
|
|
{
|
|
locals = (insn & 0xf) | ((insn & 0x0f00) >> 4);
|
|
insn = extract_unsigned_integer (&prologue[vpc + 2], 2, byte_order);
|
|
/* ldi r29,hi8(<RAM_ADDR> - <LOCALS_SIZE>) */
|
|
if ((insn & 0xf0f0) == 0xe0d0)
|
|
{
|
|
locals |= ((insn & 0xf) | ((insn & 0x0f00) >> 4)) << 8;
|
|
if (vpc + 4 + sizeof (img) < len
|
|
&& memcmp (prologue + vpc + 4, img, sizeof (img)) == 0)
|
|
{
|
|
info->prologue_type = AVR_PROLOGUE_MAIN;
|
|
info->base = locals;
|
|
return pc_beg + 4;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Scanning `-mcall-prologues' prologue
|
|
Classic prologue is 10 bytes, mega prologue is a 12 bytes long */
|
|
|
|
while (1) /* Using a while to avoid many goto's */
|
|
{
|
|
int loc_size;
|
|
int body_addr;
|
|
unsigned num_pushes;
|
|
int pc_offset = 0;
|
|
|
|
/* At least the fifth instruction must have been executed to
|
|
modify frame shape. */
|
|
if (len < 10)
|
|
break;
|
|
|
|
insn = extract_unsigned_integer (&prologue[vpc], 2, byte_order);
|
|
/* ldi r26,<LOCALS_SIZE> */
|
|
if ((insn & 0xf0f0) != 0xe0a0)
|
|
break;
|
|
loc_size = (insn & 0xf) | ((insn & 0x0f00) >> 4);
|
|
pc_offset += 2;
|
|
|
|
insn = extract_unsigned_integer (&prologue[vpc + 2], 2, byte_order);
|
|
/* ldi r27,<LOCALS_SIZE> / 256 */
|
|
if ((insn & 0xf0f0) != 0xe0b0)
|
|
break;
|
|
loc_size |= ((insn & 0xf) | ((insn & 0x0f00) >> 4)) << 8;
|
|
pc_offset += 2;
|
|
|
|
insn = extract_unsigned_integer (&prologue[vpc + 4], 2, byte_order);
|
|
/* ldi r30,pm_lo8(.L_foo_body) */
|
|
if ((insn & 0xf0f0) != 0xe0e0)
|
|
break;
|
|
body_addr = (insn & 0xf) | ((insn & 0x0f00) >> 4);
|
|
pc_offset += 2;
|
|
|
|
insn = extract_unsigned_integer (&prologue[vpc + 6], 2, byte_order);
|
|
/* ldi r31,pm_hi8(.L_foo_body) */
|
|
if ((insn & 0xf0f0) != 0xe0f0)
|
|
break;
|
|
body_addr |= ((insn & 0xf) | ((insn & 0x0f00) >> 4)) << 8;
|
|
pc_offset += 2;
|
|
|
|
msymbol = lookup_minimal_symbol ("__prologue_saves__", NULL, NULL);
|
|
if (!msymbol)
|
|
break;
|
|
|
|
insn = extract_unsigned_integer (&prologue[vpc + 8], 2, byte_order);
|
|
/* rjmp __prologue_saves__+RRR */
|
|
if ((insn & 0xf000) == 0xc000)
|
|
{
|
|
/* Extract PC relative offset from RJMP */
|
|
i = (insn & 0xfff) | (insn & 0x800 ? (-1 ^ 0xfff) : 0);
|
|
/* Convert offset to byte addressable mode */
|
|
i *= 2;
|
|
/* Destination address */
|
|
i += pc_beg + 10;
|
|
|
|
if (body_addr != (pc_beg + 10)/2)
|
|
break;
|
|
|
|
pc_offset += 2;
|
|
}
|
|
else if ((insn & 0xfe0e) == 0x940c)
|
|
{
|
|
/* Extract absolute PC address from JMP */
|
|
i = (((insn & 0x1) | ((insn & 0x1f0) >> 3) << 16)
|
|
| (extract_unsigned_integer (&prologue[vpc + 10], 2, byte_order)
|
|
& 0xffff));
|
|
/* Convert address to byte addressable mode */
|
|
i *= 2;
|
|
|
|
if (body_addr != (pc_beg + 12)/2)
|
|
break;
|
|
|
|
pc_offset += 4;
|
|
}
|
|
else
|
|
break;
|
|
|
|
/* Resolve offset (in words) from __prologue_saves__ symbol.
|
|
Which is a pushes count in `-mcall-prologues' mode */
|
|
num_pushes = AVR_MAX_PUSHES - (i - SYMBOL_VALUE_ADDRESS (msymbol)) / 2;
|
|
|
|
if (num_pushes > AVR_MAX_PUSHES)
|
|
{
|
|
fprintf_unfiltered (gdb_stderr, _("Num pushes too large: %d\n"),
|
|
num_pushes);
|
|
num_pushes = 0;
|
|
}
|
|
|
|
if (num_pushes)
|
|
{
|
|
int from;
|
|
|
|
info->saved_regs[AVR_FP_REGNUM + 1].addr = num_pushes;
|
|
if (num_pushes >= 2)
|
|
info->saved_regs[AVR_FP_REGNUM].addr = num_pushes - 1;
|
|
|
|
i = 0;
|
|
for (from = AVR_LAST_PUSHED_REGNUM + 1 - (num_pushes - 2);
|
|
from <= AVR_LAST_PUSHED_REGNUM; ++from)
|
|
info->saved_regs [from].addr = ++i;
|
|
}
|
|
info->size = loc_size + num_pushes;
|
|
info->prologue_type = AVR_PROLOGUE_CALL;
|
|
|
|
return pc_beg + pc_offset;
|
|
}
|
|
|
|
/* Scan for the beginning of the prologue for an interrupt or signal
|
|
function. Note that we have to set the prologue type here since the
|
|
third stage of the prologue may not be present (e.g. no saved registered
|
|
or changing of the SP register). */
|
|
|
|
if (1)
|
|
{
|
|
static const unsigned char img[] = {
|
|
0x78, 0x94, /* sei */
|
|
0x1f, 0x92, /* push r1 */
|
|
0x0f, 0x92, /* push r0 */
|
|
0x0f, 0xb6, /* in r0,0x3f SREG */
|
|
0x0f, 0x92, /* push r0 */
|
|
0x11, 0x24 /* clr r1 */
|
|
};
|
|
if (len >= sizeof (img)
|
|
&& memcmp (prologue, img, sizeof (img)) == 0)
|
|
{
|
|
info->prologue_type = AVR_PROLOGUE_INTR;
|
|
vpc += sizeof (img);
|
|
info->saved_regs[AVR_SREG_REGNUM].addr = 3;
|
|
info->saved_regs[0].addr = 2;
|
|
info->saved_regs[1].addr = 1;
|
|
info->size += 3;
|
|
}
|
|
else if (len >= sizeof (img) - 2
|
|
&& memcmp (img + 2, prologue, sizeof (img) - 2) == 0)
|
|
{
|
|
info->prologue_type = AVR_PROLOGUE_SIG;
|
|
vpc += sizeof (img) - 2;
|
|
info->saved_regs[AVR_SREG_REGNUM].addr = 3;
|
|
info->saved_regs[0].addr = 2;
|
|
info->saved_regs[1].addr = 1;
|
|
info->size += 2;
|
|
}
|
|
}
|
|
|
|
/* First stage of the prologue scanning.
|
|
Scan pushes (saved registers) */
|
|
|
|
for (; vpc < len; vpc += 2)
|
|
{
|
|
insn = extract_unsigned_integer (&prologue[vpc], 2, byte_order);
|
|
if ((insn & 0xfe0f) == 0x920f) /* push rXX */
|
|
{
|
|
/* Bits 4-9 contain a mask for registers R0-R32. */
|
|
int regno = (insn & 0x1f0) >> 4;
|
|
info->size++;
|
|
info->saved_regs[regno].addr = info->size;
|
|
scan_stage = 1;
|
|
}
|
|
else
|
|
break;
|
|
}
|
|
|
|
gdb_assert (vpc < AVR_MAX_PROLOGUE_SIZE);
|
|
|
|
/* Handle static small stack allocation using rcall or push. */
|
|
|
|
while (scan_stage == 1 && vpc < len)
|
|
{
|
|
insn = extract_unsigned_integer (&prologue[vpc], 2, byte_order);
|
|
if (insn == 0xd000) /* rcall .+0 */
|
|
{
|
|
info->size += gdbarch_tdep (gdbarch)->call_length;
|
|
vpc += 2;
|
|
}
|
|
else if (insn == 0x920f) /* push r0 */
|
|
{
|
|
info->size += 1;
|
|
vpc += 2;
|
|
}
|
|
else
|
|
break;
|
|
}
|
|
|
|
/* Second stage of the prologue scanning.
|
|
Scan:
|
|
in r28,__SP_L__
|
|
in r29,__SP_H__ */
|
|
|
|
if (scan_stage == 1 && vpc < len)
|
|
{
|
|
static const unsigned char img[] = {
|
|
0xcd, 0xb7, /* in r28,__SP_L__ */
|
|
0xde, 0xb7 /* in r29,__SP_H__ */
|
|
};
|
|
unsigned short insn1;
|
|
|
|
if (vpc + sizeof (img) < len
|
|
&& memcmp (prologue + vpc, img, sizeof (img)) == 0)
|
|
{
|
|
vpc += 4;
|
|
scan_stage = 2;
|
|
}
|
|
}
|
|
|
|
/* Third stage of the prologue scanning. (Really two stages)
|
|
Scan for:
|
|
sbiw r28,XX or subi r28,lo8(XX)
|
|
sbci r29,hi8(XX)
|
|
in __tmp_reg__,__SREG__
|
|
cli
|
|
out __SP_H__,r29
|
|
out __SREG__,__tmp_reg__
|
|
out __SP_L__,r28 */
|
|
|
|
if (scan_stage == 2 && vpc < len)
|
|
{
|
|
int locals_size = 0;
|
|
static const unsigned char img[] = {
|
|
0x0f, 0xb6, /* in r0,0x3f */
|
|
0xf8, 0x94, /* cli */
|
|
0xde, 0xbf, /* out 0x3e,r29 ; SPH */
|
|
0x0f, 0xbe, /* out 0x3f,r0 ; SREG */
|
|
0xcd, 0xbf /* out 0x3d,r28 ; SPL */
|
|
};
|
|
static const unsigned char img_sig[] = {
|
|
0xde, 0xbf, /* out 0x3e,r29 ; SPH */
|
|
0xcd, 0xbf /* out 0x3d,r28 ; SPL */
|
|
};
|
|
static const unsigned char img_int[] = {
|
|
0xf8, 0x94, /* cli */
|
|
0xde, 0xbf, /* out 0x3e,r29 ; SPH */
|
|
0x78, 0x94, /* sei */
|
|
0xcd, 0xbf /* out 0x3d,r28 ; SPL */
|
|
};
|
|
|
|
insn = extract_unsigned_integer (&prologue[vpc], 2, byte_order);
|
|
if ((insn & 0xff30) == 0x9720) /* sbiw r28,XXX */
|
|
{
|
|
locals_size = (insn & 0xf) | ((insn & 0xc0) >> 2);
|
|
vpc += 2;
|
|
}
|
|
else if ((insn & 0xf0f0) == 0x50c0) /* subi r28,lo8(XX) */
|
|
{
|
|
locals_size = (insn & 0xf) | ((insn & 0xf00) >> 4);
|
|
vpc += 2;
|
|
insn = extract_unsigned_integer (&prologue[vpc], 2, byte_order);
|
|
vpc += 2;
|
|
locals_size += ((insn & 0xf) | ((insn & 0xf00) >> 4)) << 8;
|
|
}
|
|
else
|
|
return pc_beg + vpc;
|
|
|
|
/* Scan the last part of the prologue. May not be present for interrupt
|
|
or signal handler functions, which is why we set the prologue type
|
|
when we saw the beginning of the prologue previously. */
|
|
|
|
if (vpc + sizeof (img_sig) < len
|
|
&& memcmp (prologue + vpc, img_sig, sizeof (img_sig)) == 0)
|
|
{
|
|
vpc += sizeof (img_sig);
|
|
}
|
|
else if (vpc + sizeof (img_int) < len
|
|
&& memcmp (prologue + vpc, img_int, sizeof (img_int)) == 0)
|
|
{
|
|
vpc += sizeof (img_int);
|
|
}
|
|
if (vpc + sizeof (img) < len
|
|
&& memcmp (prologue + vpc, img, sizeof (img)) == 0)
|
|
{
|
|
info->prologue_type = AVR_PROLOGUE_NORMAL;
|
|
vpc += sizeof (img);
|
|
}
|
|
|
|
info->size += locals_size;
|
|
|
|
/* Fall through. */
|
|
}
|
|
|
|
/* If we got this far, we could not scan the prologue, so just return the pc
|
|
of the frame plus an adjustment for argument move insns. */
|
|
|
|
for (; vpc < len; vpc += 2)
|
|
{
|
|
insn = extract_unsigned_integer (&prologue[vpc], 2, byte_order);
|
|
if ((insn & 0xff00) == 0x0100) /* movw rXX, rYY */
|
|
continue;
|
|
else if ((insn & 0xfc00) == 0x2c00) /* mov rXX, rYY */
|
|
continue;
|
|
else
|
|
break;
|
|
}
|
|
|
|
return pc_beg + vpc;
|
|
}
|
|
|
|
static CORE_ADDR
|
|
avr_skip_prologue (struct gdbarch *gdbarch, CORE_ADDR pc)
|
|
{
|
|
CORE_ADDR func_addr, func_end;
|
|
CORE_ADDR post_prologue_pc;
|
|
|
|
/* See what the symbol table says */
|
|
|
|
if (!find_pc_partial_function (pc, NULL, &func_addr, &func_end))
|
|
return pc;
|
|
|
|
post_prologue_pc = skip_prologue_using_sal (gdbarch, func_addr);
|
|
if (post_prologue_pc != 0)
|
|
return max (pc, post_prologue_pc);
|
|
|
|
{
|
|
CORE_ADDR prologue_end = pc;
|
|
struct avr_unwind_cache info = {0};
|
|
struct trad_frame_saved_reg saved_regs[AVR_NUM_REGS];
|
|
|
|
info.saved_regs = saved_regs;
|
|
|
|
/* Need to run the prologue scanner to figure out if the function has a
|
|
prologue and possibly skip over moving arguments passed via registers
|
|
to other registers. */
|
|
|
|
prologue_end = avr_scan_prologue (gdbarch, func_addr, func_end, &info);
|
|
|
|
if (info.prologue_type != AVR_PROLOGUE_NONE)
|
|
return prologue_end;
|
|
}
|
|
|
|
/* Either we didn't find the start of this function (nothing we can do),
|
|
or there's no line info, or the line after the prologue is after
|
|
the end of the function (there probably isn't a prologue). */
|
|
|
|
return pc;
|
|
}
|
|
|
|
/* Not all avr devices support the BREAK insn. Those that don't should treat
|
|
it as a NOP. Thus, it should be ok. Since the avr is currently a remote
|
|
only target, this shouldn't be a problem (I hope). TRoth/2003-05-14 */
|
|
|
|
static const unsigned char *
|
|
avr_breakpoint_from_pc (struct gdbarch *gdbarch, CORE_ADDR * pcptr, int *lenptr)
|
|
{
|
|
static const unsigned char avr_break_insn [] = { 0x98, 0x95 };
|
|
*lenptr = sizeof (avr_break_insn);
|
|
return avr_break_insn;
|
|
}
|
|
|
|
/* Determine, for architecture GDBARCH, how a return value of TYPE
|
|
should be returned. If it is supposed to be returned in registers,
|
|
and READBUF is non-zero, read the appropriate value from REGCACHE,
|
|
and copy it into READBUF. If WRITEBUF is non-zero, write the value
|
|
from WRITEBUF into REGCACHE. */
|
|
|
|
static enum return_value_convention
|
|
avr_return_value (struct gdbarch *gdbarch, struct type *func_type,
|
|
struct type *valtype, struct regcache *regcache,
|
|
gdb_byte *readbuf, const gdb_byte *writebuf)
|
|
{
|
|
int i;
|
|
/* Single byte are returned in r24.
|
|
Otherwise, the MSB of the return value is always in r25, calculate which
|
|
register holds the LSB. */
|
|
int lsb_reg;
|
|
|
|
if ((TYPE_CODE (valtype) == TYPE_CODE_STRUCT
|
|
|| TYPE_CODE (valtype) == TYPE_CODE_UNION
|
|
|| TYPE_CODE (valtype) == TYPE_CODE_ARRAY)
|
|
&& TYPE_LENGTH (valtype) > 8)
|
|
return RETURN_VALUE_STRUCT_CONVENTION;
|
|
|
|
if (TYPE_LENGTH (valtype) <= 2)
|
|
lsb_reg = 24;
|
|
else if (TYPE_LENGTH (valtype) <= 4)
|
|
lsb_reg = 22;
|
|
else if (TYPE_LENGTH (valtype) <= 8)
|
|
lsb_reg = 18;
|
|
else
|
|
gdb_assert (0);
|
|
|
|
if (writebuf != NULL)
|
|
{
|
|
for (i = 0; i < TYPE_LENGTH (valtype); i++)
|
|
regcache_cooked_write (regcache, lsb_reg + i, writebuf + i);
|
|
}
|
|
|
|
if (readbuf != NULL)
|
|
{
|
|
for (i = 0; i < TYPE_LENGTH (valtype); i++)
|
|
regcache_cooked_read (regcache, lsb_reg + i, readbuf + i);
|
|
}
|
|
|
|
return RETURN_VALUE_REGISTER_CONVENTION;
|
|
}
|
|
|
|
|
|
/* Put here the code to store, into fi->saved_regs, the addresses of
|
|
the saved registers of frame described by FRAME_INFO. This
|
|
includes special registers such as pc and fp saved in special ways
|
|
in the stack frame. sp is even more special: the address we return
|
|
for it IS the sp for the next frame. */
|
|
|
|
static struct avr_unwind_cache *
|
|
avr_frame_unwind_cache (struct frame_info *this_frame,
|
|
void **this_prologue_cache)
|
|
{
|
|
CORE_ADDR start_pc, current_pc;
|
|
ULONGEST prev_sp;
|
|
ULONGEST this_base;
|
|
struct avr_unwind_cache *info;
|
|
struct gdbarch *gdbarch;
|
|
struct gdbarch_tdep *tdep;
|
|
int i;
|
|
|
|
if (*this_prologue_cache)
|
|
return *this_prologue_cache;
|
|
|
|
info = FRAME_OBSTACK_ZALLOC (struct avr_unwind_cache);
|
|
*this_prologue_cache = info;
|
|
info->saved_regs = trad_frame_alloc_saved_regs (this_frame);
|
|
|
|
info->size = 0;
|
|
info->prologue_type = AVR_PROLOGUE_NONE;
|
|
|
|
start_pc = get_frame_func (this_frame);
|
|
current_pc = get_frame_pc (this_frame);
|
|
if ((start_pc > 0) && (start_pc <= current_pc))
|
|
avr_scan_prologue (get_frame_arch (this_frame),
|
|
start_pc, current_pc, info);
|
|
|
|
if ((info->prologue_type != AVR_PROLOGUE_NONE)
|
|
&& (info->prologue_type != AVR_PROLOGUE_MAIN))
|
|
{
|
|
ULONGEST high_base; /* High byte of FP */
|
|
|
|
/* The SP was moved to the FP. This indicates that a new frame
|
|
was created. Get THIS frame's FP value by unwinding it from
|
|
the next frame. */
|
|
this_base = get_frame_register_unsigned (this_frame, AVR_FP_REGNUM);
|
|
high_base = get_frame_register_unsigned (this_frame, AVR_FP_REGNUM + 1);
|
|
this_base += (high_base << 8);
|
|
|
|
/* The FP points at the last saved register. Adjust the FP back
|
|
to before the first saved register giving the SP. */
|
|
prev_sp = this_base + info->size;
|
|
}
|
|
else
|
|
{
|
|
/* Assume that the FP is this frame's SP but with that pushed
|
|
stack space added back. */
|
|
this_base = get_frame_register_unsigned (this_frame, AVR_SP_REGNUM);
|
|
prev_sp = this_base + info->size;
|
|
}
|
|
|
|
/* Add 1 here to adjust for the post-decrement nature of the push
|
|
instruction.*/
|
|
info->prev_sp = avr_make_saddr (prev_sp + 1);
|
|
info->base = avr_make_saddr (this_base);
|
|
|
|
gdbarch = get_frame_arch (this_frame);
|
|
|
|
/* Adjust all the saved registers so that they contain addresses and not
|
|
offsets. */
|
|
for (i = 0; i < gdbarch_num_regs (gdbarch) - 1; i++)
|
|
if (info->saved_regs[i].addr > 0)
|
|
info->saved_regs[i].addr = info->prev_sp - info->saved_regs[i].addr;
|
|
|
|
/* Except for the main and startup code, the return PC is always saved on
|
|
the stack and is at the base of the frame. */
|
|
|
|
if (info->prologue_type != AVR_PROLOGUE_MAIN)
|
|
info->saved_regs[AVR_PC_REGNUM].addr = info->prev_sp;
|
|
|
|
/* The previous frame's SP needed to be computed. Save the computed
|
|
value. */
|
|
tdep = gdbarch_tdep (gdbarch);
|
|
trad_frame_set_value (info->saved_regs, AVR_SP_REGNUM,
|
|
info->prev_sp - 1 + tdep->call_length);
|
|
|
|
return info;
|
|
}
|
|
|
|
static CORE_ADDR
|
|
avr_unwind_pc (struct gdbarch *gdbarch, struct frame_info *next_frame)
|
|
{
|
|
ULONGEST pc;
|
|
|
|
pc = frame_unwind_register_unsigned (next_frame, AVR_PC_REGNUM);
|
|
|
|
return avr_make_iaddr (pc);
|
|
}
|
|
|
|
static CORE_ADDR
|
|
avr_unwind_sp (struct gdbarch *gdbarch, struct frame_info *next_frame)
|
|
{
|
|
ULONGEST sp;
|
|
|
|
sp = frame_unwind_register_unsigned (next_frame, AVR_SP_REGNUM);
|
|
|
|
return avr_make_saddr (sp);
|
|
}
|
|
|
|
/* Given a GDB frame, determine the address of the calling function's
|
|
frame. This will be used to create a new GDB frame struct. */
|
|
|
|
static void
|
|
avr_frame_this_id (struct frame_info *this_frame,
|
|
void **this_prologue_cache,
|
|
struct frame_id *this_id)
|
|
{
|
|
struct avr_unwind_cache *info
|
|
= avr_frame_unwind_cache (this_frame, this_prologue_cache);
|
|
CORE_ADDR base;
|
|
CORE_ADDR func;
|
|
struct frame_id id;
|
|
|
|
/* The FUNC is easy. */
|
|
func = get_frame_func (this_frame);
|
|
|
|
/* Hopefully the prologue analysis either correctly determined the
|
|
frame's base (which is the SP from the previous frame), or set
|
|
that base to "NULL". */
|
|
base = info->prev_sp;
|
|
if (base == 0)
|
|
return;
|
|
|
|
id = frame_id_build (base, func);
|
|
(*this_id) = id;
|
|
}
|
|
|
|
static struct value *
|
|
avr_frame_prev_register (struct frame_info *this_frame,
|
|
void **this_prologue_cache, int regnum)
|
|
{
|
|
struct gdbarch *gdbarch = get_frame_arch (this_frame);
|
|
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
|
|
struct avr_unwind_cache *info
|
|
= avr_frame_unwind_cache (this_frame, this_prologue_cache);
|
|
|
|
if (regnum == AVR_PC_REGNUM || regnum == AVR_PSEUDO_PC_REGNUM)
|
|
{
|
|
if (trad_frame_addr_p (info->saved_regs, AVR_PC_REGNUM))
|
|
{
|
|
/* Reading the return PC from the PC register is slightly
|
|
abnormal. register_size(AVR_PC_REGNUM) says it is 4 bytes,
|
|
but in reality, only two bytes (3 in upcoming mega256) are
|
|
stored on the stack.
|
|
|
|
Also, note that the value on the stack is an addr to a word
|
|
not a byte, so we will need to multiply it by two at some
|
|
point.
|
|
|
|
And to confuse matters even more, the return address stored
|
|
on the stack is in big endian byte order, even though most
|
|
everything else about the avr is little endian. Ick! */
|
|
ULONGEST pc;
|
|
int i;
|
|
unsigned char buf[3];
|
|
struct gdbarch *gdbarch = get_frame_arch (this_frame);
|
|
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
|
|
|
|
read_memory (info->saved_regs[AVR_PC_REGNUM].addr,
|
|
buf, tdep->call_length);
|
|
|
|
/* Extract the PC read from memory as a big-endian. */
|
|
pc = 0;
|
|
for (i = 0; i < tdep->call_length; i++)
|
|
pc = (pc << 8) | buf[i];
|
|
|
|
if (regnum == AVR_PC_REGNUM)
|
|
pc <<= 1;
|
|
|
|
return frame_unwind_got_constant (this_frame, regnum, pc);
|
|
}
|
|
|
|
return frame_unwind_got_optimized (this_frame, regnum);
|
|
}
|
|
|
|
return trad_frame_get_prev_register (this_frame, info->saved_regs, regnum);
|
|
}
|
|
|
|
static const struct frame_unwind avr_frame_unwind = {
|
|
NORMAL_FRAME,
|
|
avr_frame_this_id,
|
|
avr_frame_prev_register,
|
|
NULL,
|
|
default_frame_sniffer
|
|
};
|
|
|
|
static CORE_ADDR
|
|
avr_frame_base_address (struct frame_info *this_frame, void **this_cache)
|
|
{
|
|
struct avr_unwind_cache *info
|
|
= avr_frame_unwind_cache (this_frame, this_cache);
|
|
|
|
return info->base;
|
|
}
|
|
|
|
static const struct frame_base avr_frame_base = {
|
|
&avr_frame_unwind,
|
|
avr_frame_base_address,
|
|
avr_frame_base_address,
|
|
avr_frame_base_address
|
|
};
|
|
|
|
/* Assuming THIS_FRAME 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 the PC match the dummy frame's breakpoint. */
|
|
|
|
static struct frame_id
|
|
avr_dummy_id (struct gdbarch *gdbarch, struct frame_info *this_frame)
|
|
{
|
|
ULONGEST base;
|
|
|
|
base = get_frame_register_unsigned (this_frame, AVR_SP_REGNUM);
|
|
return frame_id_build (avr_make_saddr (base), get_frame_pc (this_frame));
|
|
}
|
|
|
|
/* When arguments must be pushed onto the stack, they go on in reverse
|
|
order. The 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, const bfd_byte *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);
|
|
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;
|
|
}
|
|
|
|
/* Setup the function arguments for calling a function in the inferior.
|
|
|
|
On the AVR architecture, there are 18 registers (R25 to R8) which are
|
|
dedicated for passing function arguments. Up to the first 18 arguments
|
|
(depending on size) may go into these registers. The rest go on the stack.
|
|
|
|
All arguments are aligned to start in even-numbered registers (odd-sized
|
|
arguments, including char, have one free register above them). For example,
|
|
an int in arg1 and a char in arg2 would be passed as such:
|
|
|
|
arg1 -> r25:r24
|
|
arg2 -> r22
|
|
|
|
Arguments that are larger than 2 bytes will be split between two or more
|
|
registers as available, but will NOT be split between a register and the
|
|
stack. Arguments that go onto the stack are pushed last arg first (this is
|
|
similar to the d10v). */
|
|
|
|
/* NOTE: TRoth/2003-06-17: The rest of this comment is old looks to be
|
|
inaccurate.
|
|
|
|
An exceptional case exists for struct arguments (and possibly other
|
|
aggregates such as arrays) -- if the size is larger than WORDSIZE bytes but
|
|
not a multiple of WORDSIZE bytes. In this case the argument is never split
|
|
between the registers and the stack, but instead is copied in its entirety
|
|
onto the stack, AND also copied into as many registers as there is room
|
|
for. In other words, space in registers permitting, two copies of the same
|
|
argument are passed in. As far as I can tell, only the one on the stack is
|
|
used, although that may be a function of the level of compiler
|
|
optimization. I suspect this is a compiler bug. Arguments of these odd
|
|
sizes are left-justified within the word (as opposed to arguments smaller
|
|
than WORDSIZE bytes, which are right-justified).
|
|
|
|
If the function is to return an aggregate type such as a struct, the caller
|
|
must allocate space into which the callee will copy the return value. In
|
|
this case, a pointer to the return value location is passed into the callee
|
|
in register R0, which displaces one of the other arguments passed in via
|
|
registers R0 to R2. */
|
|
|
|
static CORE_ADDR
|
|
avr_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)
|
|
{
|
|
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
|
|
int i;
|
|
unsigned char buf[3];
|
|
int call_length = gdbarch_tdep (gdbarch)->call_length;
|
|
CORE_ADDR return_pc = avr_convert_iaddr_to_raw (bp_addr);
|
|
int regnum = AVR_ARGN_REGNUM;
|
|
struct stack_item *si = NULL;
|
|
|
|
if (struct_return)
|
|
{
|
|
regcache_cooked_write_unsigned
|
|
(regcache, regnum--, (struct_addr >> 8) & 0xff);
|
|
regcache_cooked_write_unsigned
|
|
(regcache, regnum--, struct_addr & 0xff);
|
|
/* SP being post decremented, we need to reserve one byte so that the
|
|
return address won't overwrite the result (or vice-versa). */
|
|
if (sp == struct_addr)
|
|
sp--;
|
|
}
|
|
|
|
for (i = 0; i < nargs; i++)
|
|
{
|
|
int last_regnum;
|
|
int j;
|
|
struct value *arg = args[i];
|
|
struct type *type = check_typedef (value_type (arg));
|
|
const bfd_byte *contents = value_contents (arg);
|
|
int len = TYPE_LENGTH (type);
|
|
|
|
/* Calculate the potential last register needed. */
|
|
last_regnum = regnum - (len + (len & 1));
|
|
|
|
/* If there are registers available, use them. Once we start putting
|
|
stuff on the stack, all subsequent args go on stack. */
|
|
if ((si == NULL) && (last_regnum >= 8))
|
|
{
|
|
ULONGEST val;
|
|
|
|
/* Skip a register for odd length args. */
|
|
if (len & 1)
|
|
regnum--;
|
|
|
|
val = extract_unsigned_integer (contents, len, byte_order);
|
|
for (j = 0; j < len; j++)
|
|
regcache_cooked_write_unsigned
|
|
(regcache, regnum--, val >> (8 * (len - j - 1)));
|
|
}
|
|
/* No registers available, push the args onto the stack. */
|
|
else
|
|
{
|
|
/* From here on, we don't care about regnum. */
|
|
si = push_stack_item (si, contents, len);
|
|
}
|
|
}
|
|
|
|
/* Push args onto the stack. */
|
|
while (si)
|
|
{
|
|
sp -= si->len;
|
|
/* Add 1 to sp here to account for post decr nature of pushes. */
|
|
write_memory (sp + 1, si->data, si->len);
|
|
si = pop_stack_item (si);
|
|
}
|
|
|
|
/* Set the return address. For the avr, the return address is the BP_ADDR.
|
|
Need to push the return address onto the stack noting that it needs to be
|
|
in big-endian order on the stack. */
|
|
for (i = 1; i <= call_length; i++)
|
|
{
|
|
buf[call_length - i] = return_pc & 0xff;
|
|
return_pc >>= 8;
|
|
}
|
|
|
|
sp -= call_length;
|
|
/* Use 'sp + 1' since pushes are post decr ops. */
|
|
write_memory (sp + 1, buf, call_length);
|
|
|
|
/* Finally, update the SP register. */
|
|
regcache_cooked_write_unsigned (regcache, AVR_SP_REGNUM,
|
|
avr_convert_saddr_to_raw (sp));
|
|
|
|
/* Return SP value for the dummy frame, where the return address hasn't been
|
|
pushed. */
|
|
return sp + call_length;
|
|
}
|
|
|
|
/* Unfortunately dwarf2 register for SP is 32. */
|
|
|
|
static int
|
|
avr_dwarf_reg_to_regnum (struct gdbarch *gdbarch, int reg)
|
|
{
|
|
if (reg >= 0 && reg < 32)
|
|
return reg;
|
|
if (reg == 32)
|
|
return AVR_SP_REGNUM;
|
|
|
|
warning (_("Unmapped DWARF Register #%d encountered."), reg);
|
|
|
|
return -1;
|
|
}
|
|
|
|
/* Initialize the gdbarch structure for the AVR's. */
|
|
|
|
static struct gdbarch *
|
|
avr_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
|
|
{
|
|
struct gdbarch *gdbarch;
|
|
struct gdbarch_tdep *tdep;
|
|
struct gdbarch_list *best_arch;
|
|
int call_length;
|
|
|
|
/* Avr-6 call instructions save 3 bytes. */
|
|
switch (info.bfd_arch_info->mach)
|
|
{
|
|
case bfd_mach_avr1:
|
|
case bfd_mach_avr2:
|
|
case bfd_mach_avr3:
|
|
case bfd_mach_avr4:
|
|
case bfd_mach_avr5:
|
|
default:
|
|
call_length = 2;
|
|
break;
|
|
case bfd_mach_avr6:
|
|
call_length = 3;
|
|
break;
|
|
}
|
|
|
|
/* 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 (gdbarch_tdep (best_arch->gdbarch)->call_length == call_length)
|
|
return best_arch->gdbarch;
|
|
}
|
|
|
|
/* None found, create a new architecture from the information provided. */
|
|
tdep = XMALLOC (struct gdbarch_tdep);
|
|
gdbarch = gdbarch_alloc (&info, tdep);
|
|
|
|
tdep->call_length = call_length;
|
|
|
|
/* Create a type for PC. We can't use builtin types here, as they may not
|
|
be defined. */
|
|
tdep->void_type = arch_type (gdbarch, TYPE_CODE_VOID, 1, "void");
|
|
tdep->func_void_type = make_function_type (tdep->void_type, NULL);
|
|
tdep->pc_type = arch_type (gdbarch, TYPE_CODE_PTR, 4, NULL);
|
|
TYPE_TARGET_TYPE (tdep->pc_type) = tdep->func_void_type;
|
|
TYPE_UNSIGNED (tdep->pc_type) = 1;
|
|
|
|
set_gdbarch_short_bit (gdbarch, 2 * TARGET_CHAR_BIT);
|
|
set_gdbarch_int_bit (gdbarch, 2 * TARGET_CHAR_BIT);
|
|
set_gdbarch_long_bit (gdbarch, 4 * TARGET_CHAR_BIT);
|
|
set_gdbarch_long_long_bit (gdbarch, 8 * TARGET_CHAR_BIT);
|
|
set_gdbarch_ptr_bit (gdbarch, 2 * TARGET_CHAR_BIT);
|
|
set_gdbarch_addr_bit (gdbarch, 32);
|
|
|
|
set_gdbarch_float_bit (gdbarch, 4 * TARGET_CHAR_BIT);
|
|
set_gdbarch_double_bit (gdbarch, 4 * TARGET_CHAR_BIT);
|
|
set_gdbarch_long_double_bit (gdbarch, 4 * TARGET_CHAR_BIT);
|
|
|
|
set_gdbarch_float_format (gdbarch, floatformats_ieee_single);
|
|
set_gdbarch_double_format (gdbarch, floatformats_ieee_single);
|
|
set_gdbarch_long_double_format (gdbarch, floatformats_ieee_single);
|
|
|
|
set_gdbarch_read_pc (gdbarch, avr_read_pc);
|
|
set_gdbarch_write_pc (gdbarch, avr_write_pc);
|
|
|
|
set_gdbarch_num_regs (gdbarch, AVR_NUM_REGS);
|
|
|
|
set_gdbarch_sp_regnum (gdbarch, AVR_SP_REGNUM);
|
|
set_gdbarch_pc_regnum (gdbarch, AVR_PC_REGNUM);
|
|
|
|
set_gdbarch_register_name (gdbarch, avr_register_name);
|
|
set_gdbarch_register_type (gdbarch, avr_register_type);
|
|
|
|
set_gdbarch_num_pseudo_regs (gdbarch, AVR_NUM_PSEUDO_REGS);
|
|
set_gdbarch_pseudo_register_read (gdbarch, avr_pseudo_register_read);
|
|
set_gdbarch_pseudo_register_write (gdbarch, avr_pseudo_register_write);
|
|
|
|
set_gdbarch_return_value (gdbarch, avr_return_value);
|
|
set_gdbarch_print_insn (gdbarch, print_insn_avr);
|
|
|
|
set_gdbarch_push_dummy_call (gdbarch, avr_push_dummy_call);
|
|
|
|
set_gdbarch_dwarf2_reg_to_regnum (gdbarch, avr_dwarf_reg_to_regnum);
|
|
|
|
set_gdbarch_address_to_pointer (gdbarch, avr_address_to_pointer);
|
|
set_gdbarch_pointer_to_address (gdbarch, avr_pointer_to_address);
|
|
set_gdbarch_integer_to_address (gdbarch, avr_integer_to_address);
|
|
|
|
set_gdbarch_skip_prologue (gdbarch, avr_skip_prologue);
|
|
set_gdbarch_inner_than (gdbarch, core_addr_lessthan);
|
|
|
|
set_gdbarch_breakpoint_from_pc (gdbarch, avr_breakpoint_from_pc);
|
|
|
|
frame_unwind_append_unwinder (gdbarch, &avr_frame_unwind);
|
|
frame_base_set_default (gdbarch, &avr_frame_base);
|
|
|
|
set_gdbarch_dummy_id (gdbarch, avr_dummy_id);
|
|
|
|
set_gdbarch_unwind_pc (gdbarch, avr_unwind_pc);
|
|
set_gdbarch_unwind_sp (gdbarch, avr_unwind_sp);
|
|
|
|
return gdbarch;
|
|
}
|
|
|
|
/* Send a query request to the avr remote target asking for values of the io
|
|
registers. If args parameter is not NULL, then the user has requested info
|
|
on a specific io register [This still needs implemented and is ignored for
|
|
now]. The query string should be one of these forms:
|
|
|
|
"Ravr.io_reg" -> reply is "NN" number of io registers
|
|
|
|
"Ravr.io_reg:addr,len" where addr is first register and len is number of
|
|
registers to be read. The reply should be "<NAME>,VV;" for each io register
|
|
where, <NAME> is a string, and VV is the hex value of the register.
|
|
|
|
All io registers are 8-bit. */
|
|
|
|
static void
|
|
avr_io_reg_read_command (char *args, int from_tty)
|
|
{
|
|
LONGEST bufsiz = 0;
|
|
gdb_byte *buf;
|
|
char query[400];
|
|
char *p;
|
|
unsigned int nreg = 0;
|
|
unsigned int val;
|
|
int i, j, k, step;
|
|
|
|
/* Find out how many io registers the target has. */
|
|
bufsiz = target_read_alloc (¤t_target, TARGET_OBJECT_AVR,
|
|
"avr.io_reg", &buf);
|
|
|
|
if (bufsiz <= 0)
|
|
{
|
|
fprintf_unfiltered (gdb_stderr,
|
|
_("ERR: info io_registers NOT supported "
|
|
"by current target\n"));
|
|
return;
|
|
}
|
|
|
|
if (sscanf (buf, "%x", &nreg) != 1)
|
|
{
|
|
fprintf_unfiltered (gdb_stderr,
|
|
_("Error fetching number of io registers\n"));
|
|
xfree (buf);
|
|
return;
|
|
}
|
|
|
|
xfree (buf);
|
|
|
|
reinitialize_more_filter ();
|
|
|
|
printf_unfiltered (_("Target has %u io registers:\n\n"), nreg);
|
|
|
|
/* only fetch up to 8 registers at a time to keep the buffer small */
|
|
step = 8;
|
|
|
|
for (i = 0; i < nreg; i += step)
|
|
{
|
|
/* how many registers this round? */
|
|
j = step;
|
|
if ((i+j) >= nreg)
|
|
j = nreg - i; /* last block is less than 8 registers */
|
|
|
|
snprintf (query, sizeof (query) - 1, "avr.io_reg:%x,%x", i, j);
|
|
bufsiz = target_read_alloc (¤t_target, TARGET_OBJECT_AVR,
|
|
query, &buf);
|
|
|
|
p = buf;
|
|
for (k = i; k < (i + j); k++)
|
|
{
|
|
if (sscanf (p, "%[^,],%x;", query, &val) == 2)
|
|
{
|
|
printf_filtered ("[%02x] %-15s : %02x\n", k, query, val);
|
|
while ((*p != ';') && (*p != '\0'))
|
|
p++;
|
|
p++; /* skip over ';' */
|
|
if (*p == '\0')
|
|
break;
|
|
}
|
|
}
|
|
|
|
xfree (buf);
|
|
}
|
|
}
|
|
|
|
extern initialize_file_ftype _initialize_avr_tdep; /* -Wmissing-prototypes */
|
|
|
|
void
|
|
_initialize_avr_tdep (void)
|
|
{
|
|
register_gdbarch_init (bfd_arch_avr, avr_gdbarch_init);
|
|
|
|
/* Add a new command to allow the user to query the avr remote target for
|
|
the values of the io space registers in a saner way than just using
|
|
`x/NNNb ADDR`. */
|
|
|
|
/* FIXME: TRoth/2002-02-18: This should probably be changed to 'info avr
|
|
io_registers' to signify it is not available on other platforms. */
|
|
|
|
add_cmd ("io_registers", class_info, avr_io_reg_read_command,
|
|
_("query remote avr target for io space register values"),
|
|
&infolist);
|
|
}
|