| /* Altera Nios II disassemble routines |
| Copyright (C) 2012, 2013 Free Software Foundation, Inc. |
| Contributed by Nigel Gray (ngray@altera.com). |
| Contributed by Mentor Graphics, Inc. |
| |
| This file is part of the GNU opcodes library. |
| |
| This library 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, or (at your option) |
| any later version. |
| |
| It 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 file; see the file COPYING. If not, write to the |
| Free Software Foundation, 51 Franklin Street - Fifth Floor, Boston, |
| MA 02110-1301, USA. */ |
| |
| #include "sysdep.h" |
| #include "dis-asm.h" |
| #include "opcode/nios2.h" |
| #include "libiberty.h" |
| #include <string.h> |
| #include <assert.h> |
| |
| /* No symbol table is available when this code runs out in an embedded |
| system as when it is used for disassembler support in a monitor. */ |
| #if !defined(EMBEDDED_ENV) |
| #define SYMTAB_AVAILABLE 1 |
| #include "elf-bfd.h" |
| #include "elf/nios2.h" |
| #endif |
| |
| /* Length of Nios II instruction in bytes. */ |
| #define INSNLEN 4 |
| |
| /* Data structures used by the opcode hash table. */ |
| typedef struct _nios2_opcode_hash |
| { |
| const struct nios2_opcode *opcode; |
| struct _nios2_opcode_hash *next; |
| } nios2_opcode_hash; |
| |
| static bfd_boolean nios2_hash_init = 0; |
| static nios2_opcode_hash *nios2_hash[(OP_MASK_OP) + 1]; |
| |
| /* Separate hash table for pseudo-ops. */ |
| static nios2_opcode_hash *nios2_ps_hash[(OP_MASK_OP) + 1]; |
| |
| /* Function to initialize the opcode hash table. */ |
| static void |
| nios2_init_opcode_hash (void) |
| { |
| unsigned int i; |
| register const struct nios2_opcode *op; |
| |
| for (i = 0; i <= OP_MASK_OP; ++i) |
| nios2_hash[0] = NULL; |
| for (i = 0; i <= OP_MASK_OP; i++) |
| for (op = nios2_opcodes; op < &nios2_opcodes[NUMOPCODES]; op++) |
| { |
| nios2_opcode_hash *new_hash; |
| nios2_opcode_hash **bucket = NULL; |
| |
| if ((op->pinfo & NIOS2_INSN_MACRO) == NIOS2_INSN_MACRO) |
| { |
| if (i == ((op->match >> OP_SH_OP) & OP_MASK_OP) |
| && (op->pinfo & (NIOS2_INSN_MACRO_MOV | NIOS2_INSN_MACRO_MOVI) |
| & 0x7fffffff)) |
| bucket = &(nios2_ps_hash[i]); |
| } |
| else if (i == ((op->match >> OP_SH_OP) & OP_MASK_OP)) |
| bucket = &(nios2_hash[i]); |
| |
| if (bucket) |
| { |
| new_hash = |
| (nios2_opcode_hash *) malloc (sizeof (nios2_opcode_hash)); |
| if (new_hash == NULL) |
| { |
| fprintf (stderr, |
| "error allocating memory...broken disassembler\n"); |
| abort (); |
| } |
| new_hash->opcode = op; |
| new_hash->next = NULL; |
| while (*bucket) |
| bucket = &((*bucket)->next); |
| *bucket = new_hash; |
| } |
| } |
| nios2_hash_init = 1; |
| #ifdef DEBUG_HASHTABLE |
| for (i = 0; i <= OP_MASK_OP; ++i) |
| { |
| nios2_opcode_hash *tmp_hash = nios2_hash[i]; |
| printf ("index: 0x%02X ops: ", i); |
| while (tmp_hash != NULL) |
| { |
| printf ("%s ", tmp_hash->opcode->name); |
| tmp_hash = tmp_hash->next; |
| } |
| printf ("\n"); |
| } |
| |
| for (i = 0; i <= OP_MASK_OP; ++i) |
| { |
| nios2_opcode_hash *tmp_hash = nios2_ps_hash[i]; |
| printf ("index: 0x%02X ops: ", i); |
| while (tmp_hash != NULL) |
| { |
| printf ("%s ", tmp_hash->opcode->name); |
| tmp_hash = tmp_hash->next; |
| } |
| printf ("\n"); |
| } |
| #endif /* DEBUG_HASHTABLE */ |
| } |
| |
| /* Return a pointer to an nios2_opcode struct for a given instruction |
| opcode, or NULL if there is an error. */ |
| const struct nios2_opcode * |
| nios2_find_opcode_hash (unsigned long opcode) |
| { |
| nios2_opcode_hash *entry; |
| |
| /* Build a hash table to shorten the search time. */ |
| if (!nios2_hash_init) |
| nios2_init_opcode_hash (); |
| |
| /* First look in the pseudo-op hashtable. */ |
| for (entry = nios2_ps_hash[(opcode >> OP_SH_OP) & OP_MASK_OP]; |
| entry; entry = entry->next) |
| if (entry->opcode->match == (opcode & entry->opcode->mask)) |
| return entry->opcode; |
| |
| /* Otherwise look in the main hashtable. */ |
| for (entry = nios2_hash[(opcode >> OP_SH_OP) & OP_MASK_OP]; |
| entry; entry = entry->next) |
| if (entry->opcode->match == (opcode & entry->opcode->mask)) |
| return entry->opcode; |
| |
| return NULL; |
| } |
| |
| /* There are 32 regular registers, 32 coprocessor registers, |
| and 32 control registers. */ |
| #define NUMREGNAMES 32 |
| |
| /* Return a pointer to the base of the coprocessor register name array. */ |
| static struct nios2_reg * |
| nios2_coprocessor_regs (void) |
| { |
| static struct nios2_reg *cached = NULL; |
| |
| if (!cached) |
| { |
| int i; |
| for (i = NUMREGNAMES; i < nios2_num_regs; i++) |
| if (!strcmp (nios2_regs[i].name, "c0")) |
| { |
| cached = nios2_regs + i; |
| break; |
| } |
| assert (cached); |
| } |
| return cached; |
| } |
| |
| /* Return a pointer to the base of the control register name array. */ |
| static struct nios2_reg * |
| nios2_control_regs (void) |
| { |
| static struct nios2_reg *cached = NULL; |
| |
| if (!cached) |
| { |
| int i; |
| for (i = NUMREGNAMES; i < nios2_num_regs; i++) |
| if (!strcmp (nios2_regs[i].name, "status")) |
| { |
| cached = nios2_regs + i; |
| break; |
| } |
| assert (cached); |
| } |
| return cached; |
| } |
| |
| /* The function nios2_print_insn_arg uses the character pointed |
| to by ARGPTR to determine how it print the next token or separator |
| character in the arguments to an instruction. */ |
| static int |
| nios2_print_insn_arg (const char *argptr, |
| unsigned long opcode, bfd_vma address, |
| disassemble_info *info) |
| { |
| unsigned long i = 0; |
| struct nios2_reg *reg_base; |
| |
| switch (*argptr) |
| { |
| case ',': |
| case '(': |
| case ')': |
| (*info->fprintf_func) (info->stream, "%c", *argptr); |
| break; |
| case 'd': |
| i = GET_INSN_FIELD (RRD, opcode); |
| |
| if (GET_INSN_FIELD (OP, opcode) == OP_MATCH_CUSTOM |
| && GET_INSN_FIELD (CUSTOM_C, opcode) == 0) |
| reg_base = nios2_coprocessor_regs (); |
| else |
| reg_base = nios2_regs; |
| |
| if (i < NUMREGNAMES) |
| (*info->fprintf_func) (info->stream, "%s", reg_base[i].name); |
| else |
| (*info->fprintf_func) (info->stream, "unknown"); |
| break; |
| case 's': |
| i = GET_INSN_FIELD (RRS, opcode); |
| |
| if (GET_INSN_FIELD (OP, opcode) == OP_MATCH_CUSTOM |
| && GET_INSN_FIELD (CUSTOM_A, opcode) == 0) |
| reg_base = nios2_coprocessor_regs (); |
| else |
| reg_base = nios2_regs; |
| |
| if (i < NUMREGNAMES) |
| (*info->fprintf_func) (info->stream, "%s", reg_base[i].name); |
| else |
| (*info->fprintf_func) (info->stream, "unknown"); |
| break; |
| case 't': |
| i = GET_INSN_FIELD (RRT, opcode); |
| |
| if (GET_INSN_FIELD (OP, opcode) == OP_MATCH_CUSTOM |
| && GET_INSN_FIELD (CUSTOM_B, opcode) == 0) |
| reg_base = nios2_coprocessor_regs (); |
| else |
| reg_base = nios2_regs; |
| |
| if (i < NUMREGNAMES) |
| (*info->fprintf_func) (info->stream, "%s", reg_base[i].name); |
| else |
| (*info->fprintf_func) (info->stream, "unknown"); |
| break; |
| case 'i': |
| /* 16-bit signed immediate. */ |
| i = (signed) (GET_INSN_FIELD (IMM16, opcode) << 16) >> 16; |
| (*info->fprintf_func) (info->stream, "%ld", i); |
| break; |
| case 'u': |
| /* 16-bit unsigned immediate. */ |
| i = GET_INSN_FIELD (IMM16, opcode); |
| (*info->fprintf_func) (info->stream, "%ld", i); |
| break; |
| case 'o': |
| /* 16-bit signed immediate address offset. */ |
| i = (signed) (GET_INSN_FIELD (IMM16, opcode) << 16) >> 16; |
| address = address + 4 + i; |
| (*info->print_address_func) (address, info); |
| break; |
| case 'p': |
| /* 5-bit unsigned immediate. */ |
| i = GET_INSN_FIELD (CACHE_OPX, opcode); |
| (*info->fprintf_func) (info->stream, "%ld", i); |
| break; |
| case 'j': |
| /* 5-bit unsigned immediate. */ |
| i = GET_INSN_FIELD (IMM5, opcode); |
| (*info->fprintf_func) (info->stream, "%ld", i); |
| break; |
| case 'l': |
| /* 8-bit unsigned immediate. */ |
| /* FIXME - not yet implemented */ |
| i = GET_INSN_FIELD (CUSTOM_N, opcode); |
| (*info->fprintf_func) (info->stream, "%lu", i); |
| break; |
| case 'm': |
| /* 26-bit unsigned immediate. */ |
| i = GET_INSN_FIELD (IMM26, opcode); |
| /* This translates to an address because it's only used in call |
| instructions. */ |
| address = (address & 0xf0000000) | (i << 2); |
| (*info->print_address_func) (address, info); |
| break; |
| case 'c': |
| /* Control register index. */ |
| i = GET_INSN_FIELD (IMM5, opcode); |
| reg_base = nios2_control_regs (); |
| (*info->fprintf_func) (info->stream, "%s", reg_base[i].name); |
| break; |
| case 'b': |
| i = GET_INSN_FIELD (IMM5, opcode); |
| (*info->fprintf_func) (info->stream, "%ld", i); |
| break; |
| default: |
| (*info->fprintf_func) (info->stream, "unknown"); |
| break; |
| } |
| return 0; |
| } |
| |
| /* nios2_disassemble does all the work of disassembling a Nios II |
| instruction opcode. */ |
| static int |
| nios2_disassemble (bfd_vma address, unsigned long opcode, |
| disassemble_info *info) |
| { |
| const struct nios2_opcode *op; |
| |
| info->bytes_per_line = INSNLEN; |
| info->bytes_per_chunk = INSNLEN; |
| info->display_endian = info->endian; |
| info->insn_info_valid = 1; |
| info->branch_delay_insns = 0; |
| info->data_size = 0; |
| info->insn_type = dis_nonbranch; |
| info->target = 0; |
| info->target2 = 0; |
| |
| /* Find the major opcode and use this to disassemble |
| the instruction and its arguments. */ |
| op = nios2_find_opcode_hash (opcode); |
| |
| if (op != NULL) |
| { |
| bfd_boolean is_nop = FALSE; |
| if (op->pinfo == NIOS2_INSN_MACRO_MOV) |
| { |
| /* Check for mov r0, r0 and change to nop. */ |
| int dst, src; |
| dst = GET_INSN_FIELD (RRD, opcode); |
| src = GET_INSN_FIELD (RRS, opcode); |
| if (dst == 0 && src == 0) |
| { |
| (*info->fprintf_func) (info->stream, "nop"); |
| is_nop = TRUE; |
| } |
| else |
| (*info->fprintf_func) (info->stream, "%s", op->name); |
| } |
| else |
| (*info->fprintf_func) (info->stream, "%s", op->name); |
| |
| if (!is_nop) |
| { |
| const char *argstr = op->args; |
| if (argstr != NULL && *argstr != '\0') |
| { |
| (*info->fprintf_func) (info->stream, "\t"); |
| while (*argstr != '\0') |
| { |
| nios2_print_insn_arg (argstr, opcode, address, info); |
| ++argstr; |
| } |
| } |
| } |
| } |
| else |
| { |
| /* Handle undefined instructions. */ |
| info->insn_type = dis_noninsn; |
| (*info->fprintf_func) (info->stream, "0x%lx", opcode); |
| } |
| /* Tell the caller how far to advance the program counter. */ |
| return INSNLEN; |
| } |
| |
| |
| /* print_insn_nios2 is the main disassemble function for Nios II. |
| The function diassembler(abfd) (source in disassemble.c) returns a |
| pointer to this either print_insn_big_nios2 or |
| print_insn_little_nios2, which in turn call this function when the |
| bfd machine type is Nios II. print_insn_nios2 reads the |
| instruction word at the address given, and prints the disassembled |
| instruction on the stream info->stream using info->fprintf_func. */ |
| |
| static int |
| print_insn_nios2 (bfd_vma address, disassemble_info *info, |
| enum bfd_endian endianness) |
| { |
| bfd_byte buffer[INSNLEN]; |
| int status; |
| |
| status = (*info->read_memory_func) (address, buffer, INSNLEN, info); |
| if (status == 0) |
| { |
| unsigned long insn; |
| if (endianness == BFD_ENDIAN_BIG) |
| insn = (unsigned long) bfd_getb32 (buffer); |
| else |
| insn = (unsigned long) bfd_getl32 (buffer); |
| status = nios2_disassemble (address, insn, info); |
| } |
| else |
| { |
| (*info->memory_error_func) (status, address, info); |
| status = -1; |
| } |
| return status; |
| } |
| |
| /* These two functions are the main entry points, accessed from |
| disassemble.c. */ |
| int |
| print_insn_big_nios2 (bfd_vma address, disassemble_info *info) |
| { |
| return print_insn_nios2 (address, info, BFD_ENDIAN_BIG); |
| } |
| |
| int |
| print_insn_little_nios2 (bfd_vma address, disassemble_info *info) |
| { |
| return print_insn_nios2 (address, info, BFD_ENDIAN_LITTLE); |
| } |