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- /* Target-dependent code for Atmel AVR, for GDB.
- Copyright (C) 1996-2022 Free Software Foundation, Inc.
- This file is part of GDB.
- This program is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 3 of the License, or
- (at your option) any later version.
- This program is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
- You should have received a copy of the GNU General Public License
- along with this program. If not, see <http://www.gnu.org/licenses/>. */
- /* Contributed by Theodore A. Roth, troth@openavr.org */
- /* Portions of this file were taken from the original gdb-4.18 patch developed
- by Denis Chertykov, denisc@overta.ru */
- #include "defs.h"
- #include "frame.h"
- #include "frame-unwind.h"
- #include "frame-base.h"
- #include "trad-frame.h"
- #include "gdbcmd.h"
- #include "gdbcore.h"
- #include "gdbtypes.h"
- #include "inferior.h"
- #include "symfile.h"
- #include "arch-utils.h"
- #include "regcache.h"
- #include "dis-asm.h"
- #include "objfiles.h"
- #include <algorithm>
- #include "gdbarch.h"
- /* AVR Background:
- (AVR micros are pure Harvard Architecture processors.)
- The AVR family of microcontrollers have three distinctly different memory
- spaces: flash, sram and eeprom. The flash is 16 bits wide and is used for
- the most part to store program instructions. The sram is 8 bits wide and is
- used for the stack and the heap. Some devices lack sram and some can have
- an additional external sram added on as a peripheral.
- The eeprom is 8 bits wide and is used to store data when the device is
- powered down. Eeprom is not directly accessible, it can only be accessed
- via io-registers using a special algorithm. Accessing eeprom via gdb's
- remote serial protocol ('m' or 'M' packets) looks difficult to do and is
- not included at this time.
- [The eeprom could be read manually via ``x/b <eaddr + AVR_EMEM_START>'' or
- written using ``set {unsigned char}<eaddr + AVR_EMEM_START>''. For this to
- work, the remote target must be able to handle eeprom accesses and perform
- the address translation.]
- All three memory spaces have physical addresses beginning at 0x0. In
- addition, the flash is addressed by gcc/binutils/gdb with respect to 8 bit
- bytes instead of the 16 bit wide words used by the real device for the
- Program Counter.
- In order for remote targets to work correctly, extra bits must be added to
- addresses before they are send to the target or received from the target
- via the remote serial protocol. The extra bits are the MSBs and are used to
- decode which memory space the address is referring to. */
- /* Constants: prefixed with AVR_ to avoid name space clashes */
- /* Address space flags */
- /* We are assigning the TYPE_INSTANCE_FLAG_ADDRESS_CLASS_1 to the flash address
- space. */
- #define AVR_TYPE_ADDRESS_CLASS_FLASH TYPE_ADDRESS_CLASS_1
- #define AVR_TYPE_INSTANCE_FLAG_ADDRESS_CLASS_FLASH \
- TYPE_INSTANCE_FLAG_ADDRESS_CLASS_1
- enum
- {
- AVR_REG_W = 24,
- AVR_REG_X = 26,
- AVR_REG_Y = 28,
- AVR_FP_REGNUM = 28,
- AVR_REG_Z = 30,
- AVR_SREG_REGNUM = 32,
- AVR_SP_REGNUM = 33,
- AVR_PC_REGNUM = 34,
- AVR_NUM_REGS = 32 + 1 /*SREG*/ + 1 /*SP*/ + 1 /*PC*/,
- AVR_NUM_REG_BYTES = 32 + 1 /*SREG*/ + 2 /*SP*/ + 4 /*PC*/,
- /* Pseudo registers. */
- AVR_PSEUDO_PC_REGNUM = 35,
- AVR_NUM_PSEUDO_REGS = 1,
- AVR_PC_REG_INDEX = 35, /* index into array of registers */
- AVR_MAX_PROLOGUE_SIZE = 64, /* bytes */
- /* Count of pushed registers. From r2 to r17 (inclusively), r28, r29 */
- AVR_MAX_PUSHES = 18,
- /* Number of the last pushed register. r17 for current avr-gcc */
- AVR_LAST_PUSHED_REGNUM = 17,
- AVR_ARG1_REGNUM = 24, /* Single byte argument */
- AVR_ARGN_REGNUM = 25, /* Multi byte argments */
- AVR_LAST_ARG_REGNUM = 8, /* Last argument register */
- AVR_RET1_REGNUM = 24, /* Single byte return value */
- AVR_RETN_REGNUM = 25, /* Multi byte return value */
- /* FIXME: TRoth/2002-01-??: Can we shift all these memory masks left 8
- bits? Do these have to match the bfd vma values? It sure would make
- things easier in the future if they didn't need to match.
- Note: I chose these values so as to be consistent with bfd vma
- addresses.
- TRoth/2002-04-08: There is already a conflict with very large programs
- in the mega128. The mega128 has 128K instruction bytes (64K words),
- thus the Most Significant Bit is 0x10000 which gets masked off my
- AVR_MEM_MASK.
- The problem manifests itself when trying to set a breakpoint in a
- function which resides in the upper half of the instruction space and
- thus requires a 17-bit address.
- For now, I've just removed the EEPROM mask and changed AVR_MEM_MASK
- from 0x00ff0000 to 0x00f00000. Eeprom is not accessible from gdb yet,
- but could be for some remote targets by just adding the correct offset
- to the address and letting the remote target handle the low-level
- details of actually accessing the eeprom. */
- AVR_IMEM_START = 0x00000000, /* INSN memory */
- AVR_SMEM_START = 0x00800000, /* SRAM memory */
- #if 1
- /* No eeprom mask defined */
- AVR_MEM_MASK = 0x00f00000, /* mask to determine memory space */
- #else
- AVR_EMEM_START = 0x00810000, /* EEPROM memory */
- AVR_MEM_MASK = 0x00ff0000, /* mask to determine memory space */
- #endif
- };
- /* Prologue types:
- NORMAL and CALL are the typical types (the -mcall-prologues gcc option
- causes the generation of the CALL type prologues). */
- enum {
- AVR_PROLOGUE_NONE, /* No prologue */
- AVR_PROLOGUE_NORMAL,
- AVR_PROLOGUE_CALL, /* -mcall-prologues */
- AVR_PROLOGUE_MAIN,
- AVR_PROLOGUE_INTR, /* interrupt handler */
- AVR_PROLOGUE_SIG, /* signal handler */
- };
- /* Any function with a frame looks like this
- ....... <-SP POINTS HERE
- LOCALS1 <-FP POINTS HERE
- LOCALS0
- SAVED FP
- SAVED R3
- SAVED R2
- RET PC
- FIRST ARG
- SECOND ARG */
- struct avr_unwind_cache
- {
- /* The previous frame's inner most stack address. Used as this
- frame ID's stack_addr. */
- CORE_ADDR prev_sp;
- /* The frame's base, optionally used by the high-level debug info. */
- CORE_ADDR base;
- int size;
- int prologue_type;
- /* Table indicating the location of each and every register. */
- trad_frame_saved_reg *saved_regs;
- };
- struct avr_gdbarch_tdep : gdbarch_tdep
- {
- /* Number of bytes stored to the stack by call instructions.
- 2 bytes for avr1-5 and avrxmega1-5, 3 bytes for avr6 and avrxmega6-7. */
- int call_length = 0;
- /* Type for void. */
- struct type *void_type = nullptr;
- /* Type for a function returning void. */
- struct type *func_void_type = nullptr;
- /* Type for a pointer to a function. Used for the type of PC. */
- struct type *pc_type = nullptr;
- };
- /* Lookup the name of a register given it's number. */
- static const char *
- avr_register_name (struct gdbarch *gdbarch, int regnum)
- {
- static const char * const register_names[] = {
- "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7",
- "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15",
- "r16", "r17", "r18", "r19", "r20", "r21", "r22", "r23",
- "r24", "r25", "r26", "r27", "r28", "r29", "r30", "r31",
- "SREG", "SP", "PC2",
- "pc"
- };
- if (regnum < 0)
- return NULL;
- if (regnum >= (sizeof (register_names) / sizeof (*register_names)))
- return NULL;
- return register_names[regnum];
- }
- /* Return the GDB type object for the "standard" data type
- of data in register N. */
- static struct type *
- avr_register_type (struct gdbarch *gdbarch, int reg_nr)
- {
- if (reg_nr == AVR_PC_REGNUM)
- return builtin_type (gdbarch)->builtin_uint32;
- avr_gdbarch_tdep *tdep = (avr_gdbarch_tdep *) gdbarch_tdep (gdbarch);
- if (reg_nr == AVR_PSEUDO_PC_REGNUM)
- return tdep->pc_type;
- if (reg_nr == AVR_SP_REGNUM)
- return builtin_type (gdbarch)->builtin_data_ptr;
- return builtin_type (gdbarch)->builtin_uint8;
- }
- /* Instruction address checks and convertions. */
- static CORE_ADDR
- avr_make_iaddr (CORE_ADDR x)
- {
- return ((x) | AVR_IMEM_START);
- }
- /* FIXME: TRoth: Really need to use a larger mask for instructions. Some
- devices are already up to 128KBytes of flash space.
- TRoth/2002-04-8: See comment above where AVR_IMEM_START is defined. */
- static CORE_ADDR
- avr_convert_iaddr_to_raw (CORE_ADDR x)
- {
- return ((x) & 0xffffffff);
- }
- /* SRAM address checks and convertions. */
- static CORE_ADDR
- avr_make_saddr (CORE_ADDR x)
- {
- /* Return 0 for NULL. */
- if (x == 0)
- return 0;
- return ((x) | AVR_SMEM_START);
- }
- static CORE_ADDR
- avr_convert_saddr_to_raw (CORE_ADDR x)
- {
- return ((x) & 0xffffffff);
- }
- /* EEPROM address checks and convertions. I don't know if these will ever
- actually be used, but I've added them just the same. TRoth */
- /* TRoth/2002-04-08: Commented out for now to allow fix for problem with large
- programs in the mega128. */
- /* static CORE_ADDR */
- /* avr_make_eaddr (CORE_ADDR x) */
- /* { */
- /* return ((x) | AVR_EMEM_START); */
- /* } */
- /* static int */
- /* avr_eaddr_p (CORE_ADDR x) */
- /* { */
- /* return (((x) & AVR_MEM_MASK) == AVR_EMEM_START); */
- /* } */
- /* static CORE_ADDR */
- /* avr_convert_eaddr_to_raw (CORE_ADDR x) */
- /* { */
- /* return ((x) & 0xffffffff); */
- /* } */
- /* Convert from address to pointer and vice-versa. */
- static void
- avr_address_to_pointer (struct gdbarch *gdbarch,
- struct type *type, gdb_byte *buf, CORE_ADDR addr)
- {
- enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
- /* Is it a data address in flash? */
- if (AVR_TYPE_ADDRESS_CLASS_FLASH (type))
- {
- /* A data pointer in flash is byte addressed. */
- store_unsigned_integer (buf, TYPE_LENGTH (type), byte_order,
- avr_convert_iaddr_to_raw (addr));
- }
- /* Is it a code address? */
- else if (TYPE_TARGET_TYPE (type)->code () == TYPE_CODE_FUNC
- || TYPE_TARGET_TYPE (type)->code () == TYPE_CODE_METHOD)
- {
- /* A code pointer is word (16 bits) addressed. We shift the address down
- by 1 bit to convert it to a pointer. */
- store_unsigned_integer (buf, TYPE_LENGTH (type), byte_order,
- avr_convert_iaddr_to_raw (addr >> 1));
- }
- else
- {
- /* Strip off any upper segment bits. */
- store_unsigned_integer (buf, TYPE_LENGTH (type), byte_order,
- avr_convert_saddr_to_raw (addr));
- }
- }
- static CORE_ADDR
- avr_pointer_to_address (struct gdbarch *gdbarch,
- struct type *type, const gdb_byte *buf)
- {
- enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
- CORE_ADDR addr
- = extract_unsigned_integer (buf, TYPE_LENGTH (type), byte_order);
- /* Is it a data address in flash? */
- if (AVR_TYPE_ADDRESS_CLASS_FLASH (type))
- {
- /* A data pointer in flash is already byte addressed. */
- return avr_make_iaddr (addr);
- }
- /* Is it a code address? */
- else if (TYPE_TARGET_TYPE (type)->code () == TYPE_CODE_FUNC
- || TYPE_TARGET_TYPE (type)->code () == TYPE_CODE_METHOD
- || TYPE_CODE_SPACE (TYPE_TARGET_TYPE (type)))
- {
- /* A code pointer is word (16 bits) addressed so we shift it up
- by 1 bit to convert it to an address. */
- return avr_make_iaddr (addr << 1);
- }
- else
- return avr_make_saddr (addr);
- }
- static CORE_ADDR
- avr_integer_to_address (struct gdbarch *gdbarch,
- struct type *type, const gdb_byte *buf)
- {
- ULONGEST addr = unpack_long (type, buf);
- if (TYPE_DATA_SPACE (type))
- return avr_make_saddr (addr);
- else
- return avr_make_iaddr (addr);
- }
- static CORE_ADDR
- avr_read_pc (readable_regcache *regcache)
- {
- ULONGEST pc;
- regcache->cooked_read (AVR_PC_REGNUM, &pc);
- return avr_make_iaddr (pc);
- }
- static void
- avr_write_pc (struct regcache *regcache, CORE_ADDR val)
- {
- regcache_cooked_write_unsigned (regcache, AVR_PC_REGNUM,
- avr_convert_iaddr_to_raw (val));
- }
- static enum register_status
- avr_pseudo_register_read (struct gdbarch *gdbarch, readable_regcache *regcache,
- int regnum, gdb_byte *buf)
- {
- ULONGEST val;
- enum register_status status;
- switch (regnum)
- {
- case AVR_PSEUDO_PC_REGNUM:
- status = regcache->raw_read (AVR_PC_REGNUM, &val);
- if (status != REG_VALID)
- return status;
- val >>= 1;
- store_unsigned_integer (buf, 4, gdbarch_byte_order (gdbarch), val);
- return status;
- default:
- internal_error (__FILE__, __LINE__, _("invalid regnum"));
- }
- }
- static void
- avr_pseudo_register_write (struct gdbarch *gdbarch, struct regcache *regcache,
- int regnum, const gdb_byte *buf)
- {
- ULONGEST val;
- switch (regnum)
- {
- case AVR_PSEUDO_PC_REGNUM:
- val = extract_unsigned_integer (buf, 4, gdbarch_byte_order (gdbarch));
- val <<= 1;
- regcache_raw_write_unsigned (regcache, AVR_PC_REGNUM, val);
- break;
- default:
- internal_error (__FILE__, __LINE__, _("invalid regnum"));
- }
- }
- /* Function: avr_scan_prologue
- This function decodes an AVR function prologue to determine:
- 1) the size of the stack frame
- 2) which registers are saved on it
- 3) the offsets of saved regs
- This information is stored in the avr_unwind_cache structure.
- Some devices lack the sbiw instruction, so on those replace this:
- sbiw r28, XX
- with this:
- subi r28,lo8(XX)
- sbci r29,hi8(XX)
- A typical AVR function prologue with a frame pointer might look like this:
- push rXX ; saved regs
- ...
- push r28
- push r29
- in r28,__SP_L__
- in r29,__SP_H__
- sbiw r28,<LOCALS_SIZE>
- in __tmp_reg__,__SREG__
- cli
- out __SP_H__,r29
- out __SREG__,__tmp_reg__
- out __SP_L__,r28
- A typical AVR function prologue without a frame pointer might look like
- this:
- push rXX ; saved regs
- ...
- A main function prologue looks like this:
- ldi r28,lo8(<RAM_ADDR> - <LOCALS_SIZE>)
- ldi r29,hi8(<RAM_ADDR> - <LOCALS_SIZE>)
- out __SP_H__,r29
- out __SP_L__,r28
- A signal handler prologue looks like this:
- push __zero_reg__
- push __tmp_reg__
- in __tmp_reg__, __SREG__
- push __tmp_reg__
- clr __zero_reg__
- push rXX ; save registers r18:r27, r30:r31
- ...
- push r28 ; save frame pointer
- push r29
- in r28, __SP_L__
- in r29, __SP_H__
- sbiw r28, <LOCALS_SIZE>
- out __SP_H__, r29
- out __SP_L__, r28
-
- A interrupt handler prologue looks like this:
- sei
- push __zero_reg__
- push __tmp_reg__
- in __tmp_reg__, __SREG__
- push __tmp_reg__
- clr __zero_reg__
- push rXX ; save registers r18:r27, r30:r31
- ...
- push r28 ; save frame pointer
- push r29
- in r28, __SP_L__
- in r29, __SP_H__
- sbiw r28, <LOCALS_SIZE>
- cli
- out __SP_H__, r29
- sei
- out __SP_L__, r28
- A `-mcall-prologues' prologue looks like this (Note that the megas use a
- jmp instead of a rjmp, thus the prologue is one word larger since jmp is a
- 32 bit insn and rjmp is a 16 bit insn):
- ldi r26,lo8(<LOCALS_SIZE>)
- ldi r27,hi8(<LOCALS_SIZE>)
- ldi r30,pm_lo8(.L_foo_body)
- ldi r31,pm_hi8(.L_foo_body)
- rjmp __prologue_saves__+RRR
- .L_foo_body: */
- /* Not really part of a prologue, but still need to scan for it, is when a
- function prologue moves values passed via registers as arguments to new
- registers. In this case, all local variables live in registers, so there
- may be some register saves. This is what it looks like:
- movw rMM, rNN
- ...
- There could be multiple movw's. If the target doesn't have a movw insn, it
- will use two mov insns. This could be done after any of the above prologue
- types. */
- static CORE_ADDR
- avr_scan_prologue (struct gdbarch *gdbarch, CORE_ADDR pc_beg, CORE_ADDR pc_end,
- struct avr_unwind_cache *info)
- {
- enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
- int i;
- unsigned short insn;
- int scan_stage = 0;
- struct bound_minimal_symbol msymbol;
- 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.minsym)
- 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 - BMSYMBOL_VALUE_ADDRESS (msymbol)) / 2;
- if (num_pushes > AVR_MAX_PUSHES)
- {
- gdb_printf (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].set_addr (num_pushes);
- if (num_pushes >= 2)
- info->saved_regs[AVR_FP_REGNUM].set_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].set_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].set_addr (3);
- info->saved_regs[0].set_addr (2);
- info->saved_regs[1].set_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].set_addr (3);
- info->saved_regs[0].set_addr (2);
- info->saved_regs[1].set_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].set_addr (info->size);
- scan_stage = 1;
- }
- else
- break;
- }
- gdb_assert (vpc < AVR_MAX_PROLOGUE_SIZE);
- /* Handle static small stack allocation using rcall or push. */
- avr_gdbarch_tdep *tdep = (avr_gdbarch_tdep *) gdbarch_tdep (gdbarch);
- while (scan_stage == 1 && vpc < len)
- {
- insn = extract_unsigned_integer (&prologue[vpc], 2, byte_order);
- if (insn == 0xd000) /* rcall .+0 */
- {
- info->size += tdep->call_length;
- vpc += 2;
- }
- else if (insn == 0x920f || insn == 0x921f) /* push r0 or push r1 */
- {
- 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__ */
- };
- 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 std::max (pc, post_prologue_pc);
- {
- CORE_ADDR prologue_end = pc;
- struct avr_unwind_cache info = {0};
- 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 */
- constexpr gdb_byte avr_break_insn [] = { 0x98, 0x95 };
- typedef BP_MANIPULATION (avr_break_insn) avr_breakpoint;
- /* 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 value *function,
- 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 ((valtype->code () == TYPE_CODE_STRUCT
- || valtype->code () == TYPE_CODE_UNION
- || valtype->code () == 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_not_reached ("unexpected type length");
- if (writebuf != NULL)
- {
- for (i = 0; i < TYPE_LENGTH (valtype); i++)
- regcache->cooked_write (lsb_reg + i, writebuf + i);
- }
- if (readbuf != NULL)
- {
- for (i = 0; i < TYPE_LENGTH (valtype); i++)
- regcache->cooked_read (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;
- int i;
- if (*this_prologue_cache)
- return (struct avr_unwind_cache *) *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].is_addr ())
- info->saved_regs[i].set_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].set_addr (info->prev_sp);
- /* The previous frame's SP needed to be computed. Save the computed
- value. */
- avr_gdbarch_tdep *tdep = (avr_gdbarch_tdep *) gdbarch_tdep (gdbarch);
- info->saved_regs[AVR_SP_REGNUM].set_value (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 avr_unwind_cache *info
- = avr_frame_unwind_cache (this_frame, this_prologue_cache);
- if (regnum == AVR_PC_REGNUM || regnum == AVR_PSEUDO_PC_REGNUM)
- {
- if (info->saved_regs[AVR_PC_REGNUM].is_addr ())
- {
- /* 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;
- gdb_byte buf[3];
- struct gdbarch *gdbarch = get_frame_arch (this_frame);
- avr_gdbarch_tdep *tdep = (avr_gdbarch_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 = {
- "avr prologue",
- NORMAL_FRAME,
- default_frame_unwind_stop_reason,
- 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;
- gdb_byte *data;
- };
- static struct stack_item *
- push_stack_item (struct stack_item *prev, const bfd_byte *contents, int len)
- {
- struct stack_item *si;
- si = XNEW (struct stack_item);
- si->data = (gdb_byte *) 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,
- function_call_return_method return_method,
- CORE_ADDR struct_addr)
- {
- int i;
- gdb_byte buf[3];
- avr_gdbarch_tdep *tdep = (avr_gdbarch_tdep *) gdbarch_tdep (gdbarch);
- int call_length = tdep->call_length;
- CORE_ADDR return_pc = avr_convert_iaddr_to_raw (bp_addr);
- int regnum = AVR_ARGN_REGNUM;
- struct stack_item *si = NULL;
- if (return_method == return_method_struct)
- {
- 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).data ();
- int len = TYPE_LENGTH (type);
- /* Calculate the potential last register needed.
- E.g. For length 2, registers regnum and regnum-1 (say 25 and 24)
- shall be used. So, last needed register will be regnum-1(24). */
- last_regnum = regnum - (len + (len & 1)) + 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 >= AVR_LAST_ARG_REGNUM))
- {
- /* Skip a register for odd length args. */
- if (len & 1)
- regnum--;
- /* Write MSB of argument into register and subsequent bytes in
- decreasing register numbers. */
- for (j = 0; j < len; j++)
- regcache_cooked_write_unsigned
- (regcache, regnum--, contents[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;
- return -1;
- }
- /* Implementation of `address_class_type_flags' gdbarch method.
- This method maps DW_AT_address_class attributes to a
- type_instance_flag_value. */
- static type_instance_flags
- avr_address_class_type_flags (int byte_size, int dwarf2_addr_class)
- {
- /* The value 1 of the DW_AT_address_class attribute corresponds to the
- __flash qualifier. Note that this attribute is only valid with
- pointer types and therefore the flag is set to the pointer type and
- not its target type. */
- if (dwarf2_addr_class == 1 && byte_size == 2)
- return AVR_TYPE_INSTANCE_FLAG_ADDRESS_CLASS_FLASH;
- return 0;
- }
- /* Implementation of `address_class_type_flags_to_name' gdbarch method.
- Convert a type_instance_flag_value to an address space qualifier. */
- static const char*
- avr_address_class_type_flags_to_name (struct gdbarch *gdbarch,
- type_instance_flags type_flags)
- {
- if (type_flags & AVR_TYPE_INSTANCE_FLAG_ADDRESS_CLASS_FLASH)
- return "flash";
- else
- return NULL;
- }
- /* Implementation of `address_class_name_to_type_flags' gdbarch method.
- Convert an address space qualifier to a type_instance_flag_value. */
- static bool
- avr_address_class_name_to_type_flags (struct gdbarch *gdbarch,
- const char* name,
- type_instance_flags *type_flags_ptr)
- {
- if (strcmp (name, "flash") == 0)
- {
- *type_flags_ptr = AVR_TYPE_INSTANCE_FLAG_ADDRESS_CLASS_FLASH;
- return true;
- }
- else
- return false;
- }
- /* 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_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_avrxmega1:
- case bfd_mach_avr2:
- case bfd_mach_avrxmega2:
- case bfd_mach_avr3:
- case bfd_mach_avrxmega3:
- case bfd_mach_avr4:
- case bfd_mach_avrxmega4:
- case bfd_mach_avr5:
- case bfd_mach_avrxmega5:
- default:
- call_length = 2;
- break;
- case bfd_mach_avr6:
- case bfd_mach_avrxmega6:
- case bfd_mach_avrxmega7:
- 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))
- {
- avr_gdbarch_tdep *tdep
- = (avr_gdbarch_tdep *) gdbarch_tdep (best_arch->gdbarch);
- if (tdep->call_length == call_length)
- return best_arch->gdbarch;
- }
- /* None found, create a new architecture from the information provided. */
- avr_gdbarch_tdep *tdep = new avr_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, TARGET_CHAR_BIT,
- "void");
- tdep->func_void_type = make_function_type (tdep->void_type, NULL);
- tdep->pc_type = arch_pointer_type (gdbarch, 4 * TARGET_CHAR_BIT, NULL,
- tdep->func_void_type);
- 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_wchar_bit (gdbarch, 2 * TARGET_CHAR_BIT);
- set_gdbarch_wchar_signed (gdbarch, 1);
- 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_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_kind_from_pc (gdbarch, avr_breakpoint::kind_from_pc);
- set_gdbarch_sw_breakpoint_from_kind (gdbarch, avr_breakpoint::bp_from_kind);
- 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);
- set_gdbarch_address_class_type_flags (gdbarch, avr_address_class_type_flags);
- set_gdbarch_address_class_name_to_type_flags
- (gdbarch, avr_address_class_name_to_type_flags);
- set_gdbarch_address_class_type_flags_to_name
- (gdbarch, avr_address_class_type_flags_to_name);
- 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 (const char *args, int from_tty)
- {
- char query[400];
- unsigned int nreg = 0;
- unsigned int val;
- /* Find out how many io registers the target has. */
- gdb::optional<gdb::byte_vector> buf
- = target_read_alloc (current_inferior ()->top_target (),
- TARGET_OBJECT_AVR, "avr.io_reg");
- if (!buf)
- {
- gdb_printf (gdb_stderr,
- _("ERR: info io_registers NOT supported "
- "by current target\n"));
- return;
- }
- const char *bufstr = (const char *) buf->data ();
- if (sscanf (bufstr, "%x", &nreg) != 1)
- {
- gdb_printf (gdb_stderr,
- _("Error fetching number of io registers\n"));
- return;
- }
- gdb_printf (_("Target has %u io registers:\n\n"), nreg);
- /* only fetch up to 8 registers at a time to keep the buffer small */
- int step = 8;
- for (int i = 0; i < nreg; i += step)
- {
- /* how many registers this round? */
- int 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);
- buf = target_read_alloc (current_inferior ()->top_target (),
- TARGET_OBJECT_AVR, query);
- if (!buf)
- {
- gdb_printf (gdb_stderr,
- _("ERR: error reading avr.io_reg:%x,%x\n"),
- i, j);
- return;
- }
- const char *p = (const char *) buf->data ();
- for (int k = i; k < (i + j); k++)
- {
- if (sscanf (p, "%[^,],%x;", query, &val) == 2)
- {
- gdb_printf ("[%02x] %-15s : %02x\n", k, query, val);
- while ((*p != ';') && (*p != '\0'))
- p++;
- p++; /* skip over ';' */
- if (*p == '\0')
- break;
- }
- }
- }
- }
- void _initialize_avr_tdep ();
- void
- _initialize_avr_tdep ()
- {
- 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_info ("io_registers", avr_io_reg_read_command,
- _("Query remote AVR target for I/O space register values."));
- }
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