binutils-gdb/opcodes/riscv-dis.c

558 lines
15 KiB
C

/* RISC-V disassembler
Copyright (C) 2011-2020 Free Software Foundation, Inc.
Contributed by Andrew Waterman (andrew@sifive.com).
Based on MIPS target.
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 program; see the file COPYING3. If not,
see <http://www.gnu.org/licenses/>. */
#include "sysdep.h"
#include "disassemble.h"
#include "libiberty.h"
#include "opcode/riscv.h"
#include "opintl.h"
#include "elf-bfd.h"
#include "elf/riscv.h"
#include "bfd_stdint.h"
#include <ctype.h>
struct riscv_private_data
{
bfd_vma gp;
bfd_vma print_addr;
bfd_vma hi_addr[OP_MASK_RD + 1];
};
static const char * const *riscv_gpr_names;
static const char * const *riscv_fpr_names;
/* Other options. */
static int no_aliases; /* If set disassemble as most general inst. */
static void
set_default_riscv_dis_options (void)
{
riscv_gpr_names = riscv_gpr_names_abi;
riscv_fpr_names = riscv_fpr_names_abi;
no_aliases = 0;
}
static void
parse_riscv_dis_option (const char *option)
{
if (strcmp (option, "no-aliases") == 0)
no_aliases = 1;
else if (strcmp (option, "numeric") == 0)
{
riscv_gpr_names = riscv_gpr_names_numeric;
riscv_fpr_names = riscv_fpr_names_numeric;
}
else
{
/* xgettext:c-format */
opcodes_error_handler (_("unrecognized disassembler option: %s"), option);
}
}
static void
parse_riscv_dis_options (const char *opts_in)
{
char *opts = xstrdup (opts_in), *opt = opts, *opt_end = opts;
set_default_riscv_dis_options ();
for ( ; opt_end != NULL; opt = opt_end + 1)
{
if ((opt_end = strchr (opt, ',')) != NULL)
*opt_end = 0;
parse_riscv_dis_option (opt);
}
free (opts);
}
/* Print one argument from an array. */
static void
arg_print (struct disassemble_info *info, unsigned long val,
const char* const* array, size_t size)
{
const char *s = val >= size || array[val] == NULL ? "unknown" : array[val];
(*info->fprintf_func) (info->stream, "%s", s);
}
static void
maybe_print_address (struct riscv_private_data *pd, int base_reg, int offset)
{
if (pd->hi_addr[base_reg] != (bfd_vma)-1)
{
pd->print_addr = (base_reg != 0 ? pd->hi_addr[base_reg] : 0) + offset;
pd->hi_addr[base_reg] = -1;
}
else if (base_reg == X_GP && pd->gp != (bfd_vma)-1)
pd->print_addr = pd->gp + offset;
else if (base_reg == X_TP || base_reg == 0)
pd->print_addr = offset;
}
/* Print insn arguments for 32/64-bit code. */
static void
print_insn_args (const char *d, insn_t l, bfd_vma pc, disassemble_info *info)
{
struct riscv_private_data *pd = info->private_data;
int rs1 = (l >> OP_SH_RS1) & OP_MASK_RS1;
int rd = (l >> OP_SH_RD) & OP_MASK_RD;
fprintf_ftype print = info->fprintf_func;
if (*d != '\0')
print (info->stream, "\t");
for (; *d != '\0'; d++)
{
switch (*d)
{
case 'C': /* RVC */
switch (*++d)
{
case 's': /* RS1 x8-x15 */
case 'w': /* RS1 x8-x15 */
print (info->stream, "%s",
riscv_gpr_names[EXTRACT_OPERAND (CRS1S, l) + 8]);
break;
case 't': /* RS2 x8-x15 */
case 'x': /* RS2 x8-x15 */
print (info->stream, "%s",
riscv_gpr_names[EXTRACT_OPERAND (CRS2S, l) + 8]);
break;
case 'U': /* RS1, constrained to equal RD */
print (info->stream, "%s", riscv_gpr_names[rd]);
break;
case 'c': /* RS1, constrained to equal sp */
print (info->stream, "%s", riscv_gpr_names[X_SP]);
break;
case 'V': /* RS2 */
print (info->stream, "%s",
riscv_gpr_names[EXTRACT_OPERAND (CRS2, l)]);
break;
case 'i':
print (info->stream, "%d", (int)EXTRACT_RVC_SIMM3 (l));
break;
case 'o':
case 'j':
print (info->stream, "%d", (int)EXTRACT_RVC_IMM (l));
break;
case 'k':
print (info->stream, "%d", (int)EXTRACT_RVC_LW_IMM (l));
break;
case 'l':
print (info->stream, "%d", (int)EXTRACT_RVC_LD_IMM (l));
break;
case 'm':
print (info->stream, "%d", (int)EXTRACT_RVC_LWSP_IMM (l));
break;
case 'n':
print (info->stream, "%d", (int)EXTRACT_RVC_LDSP_IMM (l));
break;
case 'K':
print (info->stream, "%d", (int)EXTRACT_RVC_ADDI4SPN_IMM (l));
break;
case 'L':
print (info->stream, "%d", (int)EXTRACT_RVC_ADDI16SP_IMM (l));
break;
case 'M':
print (info->stream, "%d", (int)EXTRACT_RVC_SWSP_IMM (l));
break;
case 'N':
print (info->stream, "%d", (int)EXTRACT_RVC_SDSP_IMM (l));
break;
case 'p':
info->target = EXTRACT_RVC_B_IMM (l) + pc;
(*info->print_address_func) (info->target, info);
break;
case 'a':
info->target = EXTRACT_RVC_J_IMM (l) + pc;
(*info->print_address_func) (info->target, info);
break;
case 'u':
print (info->stream, "0x%x",
(int)(EXTRACT_RVC_IMM (l) & (RISCV_BIGIMM_REACH-1)));
break;
case '>':
print (info->stream, "0x%x", (int)EXTRACT_RVC_IMM (l) & 0x3f);
break;
case '<':
print (info->stream, "0x%x", (int)EXTRACT_RVC_IMM (l) & 0x1f);
break;
case 'T': /* floating-point RS2 */
print (info->stream, "%s",
riscv_fpr_names[EXTRACT_OPERAND (CRS2, l)]);
break;
case 'D': /* floating-point RS2 x8-x15 */
print (info->stream, "%s",
riscv_fpr_names[EXTRACT_OPERAND (CRS2S, l) + 8]);
break;
}
break;
case ',':
case '(':
case ')':
case '[':
case ']':
print (info->stream, "%c", *d);
break;
case '0':
/* Only print constant 0 if it is the last argument */
if (!d[1])
print (info->stream, "0");
break;
case 'b':
case 's':
if ((l & MASK_JALR) == MATCH_JALR)
maybe_print_address (pd, rs1, 0);
print (info->stream, "%s", riscv_gpr_names[rs1]);
break;
case 't':
print (info->stream, "%s",
riscv_gpr_names[EXTRACT_OPERAND (RS2, l)]);
break;
case 'u':
print (info->stream, "0x%x",
(unsigned)EXTRACT_UTYPE_IMM (l) >> RISCV_IMM_BITS);
break;
case 'm':
arg_print (info, EXTRACT_OPERAND (RM, l),
riscv_rm, ARRAY_SIZE (riscv_rm));
break;
case 'P':
arg_print (info, EXTRACT_OPERAND (PRED, l),
riscv_pred_succ, ARRAY_SIZE (riscv_pred_succ));
break;
case 'Q':
arg_print (info, EXTRACT_OPERAND (SUCC, l),
riscv_pred_succ, ARRAY_SIZE (riscv_pred_succ));
break;
case 'o':
maybe_print_address (pd, rs1, EXTRACT_ITYPE_IMM (l));
/* Fall through. */
case 'j':
if (((l & MASK_ADDI) == MATCH_ADDI && rs1 != 0)
|| (l & MASK_JALR) == MATCH_JALR)
maybe_print_address (pd, rs1, EXTRACT_ITYPE_IMM (l));
print (info->stream, "%d", (int)EXTRACT_ITYPE_IMM (l));
break;
case 'q':
maybe_print_address (pd, rs1, EXTRACT_STYPE_IMM (l));
print (info->stream, "%d", (int)EXTRACT_STYPE_IMM (l));
break;
case 'a':
info->target = EXTRACT_UJTYPE_IMM (l) + pc;
(*info->print_address_func) (info->target, info);
break;
case 'p':
info->target = EXTRACT_SBTYPE_IMM (l) + pc;
(*info->print_address_func) (info->target, info);
break;
case 'd':
if ((l & MASK_AUIPC) == MATCH_AUIPC)
pd->hi_addr[rd] = pc + EXTRACT_UTYPE_IMM (l);
else if ((l & MASK_LUI) == MATCH_LUI)
pd->hi_addr[rd] = EXTRACT_UTYPE_IMM (l);
else if ((l & MASK_C_LUI) == MATCH_C_LUI)
pd->hi_addr[rd] = EXTRACT_RVC_LUI_IMM (l);
print (info->stream, "%s", riscv_gpr_names[rd]);
break;
case 'z':
print (info->stream, "%s", riscv_gpr_names[0]);
break;
case '>':
print (info->stream, "0x%x", (int)EXTRACT_OPERAND (SHAMT, l));
break;
case '<':
print (info->stream, "0x%x", (int)EXTRACT_OPERAND (SHAMTW, l));
break;
case 'S':
case 'U':
print (info->stream, "%s", riscv_fpr_names[rs1]);
break;
case 'T':
print (info->stream, "%s", riscv_fpr_names[EXTRACT_OPERAND (RS2, l)]);
break;
case 'D':
print (info->stream, "%s", riscv_fpr_names[rd]);
break;
case 'R':
print (info->stream, "%s", riscv_fpr_names[EXTRACT_OPERAND (RS3, l)]);
break;
case 'E':
{
const char* csr_name = NULL;
unsigned int csr = EXTRACT_OPERAND (CSR, l);
switch (csr)
{
#define DECLARE_CSR(name, num) case num: csr_name = #name; break;
#include "opcode/riscv-opc.h"
#undef DECLARE_CSR
}
if (csr_name)
print (info->stream, "%s", csr_name);
else
print (info->stream, "0x%x", csr);
break;
}
case 'Z':
print (info->stream, "%d", rs1);
break;
default:
/* xgettext:c-format */
print (info->stream, _("# internal error, undefined modifier (%c)"),
*d);
return;
}
}
}
/* Print the RISC-V instruction at address MEMADDR in debugged memory,
on using INFO. Returns length of the instruction, in bytes.
BIGENDIAN must be 1 if this is big-endian code, 0 if
this is little-endian code. */
static int
riscv_disassemble_insn (bfd_vma memaddr, insn_t word, disassemble_info *info)
{
const struct riscv_opcode *op;
static bfd_boolean init = 0;
static const struct riscv_opcode *riscv_hash[OP_MASK_OP + 1];
struct riscv_private_data *pd;
int insnlen;
#define OP_HASH_IDX(i) ((i) & (riscv_insn_length (i) == 2 ? 0x3 : OP_MASK_OP))
/* Build a hash table to shorten the search time. */
if (! init)
{
for (op = riscv_opcodes; op->name; op++)
if (!riscv_hash[OP_HASH_IDX (op->match)])
riscv_hash[OP_HASH_IDX (op->match)] = op;
init = 1;
}
if (info->private_data == NULL)
{
int i;
pd = info->private_data = xcalloc (1, sizeof (struct riscv_private_data));
pd->gp = -1;
pd->print_addr = -1;
for (i = 0; i < (int)ARRAY_SIZE (pd->hi_addr); i++)
pd->hi_addr[i] = -1;
for (i = 0; i < info->symtab_size; i++)
if (strcmp (bfd_asymbol_name (info->symtab[i]), RISCV_GP_SYMBOL) == 0)
pd->gp = bfd_asymbol_value (info->symtab[i]);
}
else
pd = info->private_data;
insnlen = riscv_insn_length (word);
/* RISC-V instructions are always little-endian. */
info->endian_code = BFD_ENDIAN_LITTLE;
info->bytes_per_chunk = insnlen % 4 == 0 ? 4 : 2;
info->bytes_per_line = 8;
/* We don't support constant pools, so this must be code. */
info->display_endian = info->endian_code;
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;
op = riscv_hash[OP_HASH_IDX (word)];
if (op != NULL)
{
unsigned xlen = 0;
/* If XLEN is not known, get its value from the ELF class. */
if (info->mach == bfd_mach_riscv64)
xlen = 64;
else if (info->mach == bfd_mach_riscv32)
xlen = 32;
else if (info->section != NULL)
{
Elf_Internal_Ehdr *ehdr = elf_elfheader (info->section->owner);
xlen = ehdr->e_ident[EI_CLASS] == ELFCLASS64 ? 64 : 32;
}
for (; op->name; op++)
{
/* Does the opcode match? */
if (! (op->match_func) (op, word))
continue;
/* Is this a pseudo-instruction and may we print it as such? */
if (no_aliases && (op->pinfo & INSN_ALIAS))
continue;
/* Is this instruction restricted to a certain value of XLEN? */
if ((op->xlen_requirement != 0) && (op->xlen_requirement != xlen))
continue;
/* It's a match. */
(*info->fprintf_func) (info->stream, "%s", op->name);
print_insn_args (op->args, word, memaddr, info);
/* Try to disassemble multi-instruction addressing sequences. */
if (pd->print_addr != (bfd_vma)-1)
{
info->target = pd->print_addr;
(*info->fprintf_func) (info->stream, " # ");
(*info->print_address_func) (info->target, info);
pd->print_addr = -1;
}
/* Finish filling out insn_info fields. */
switch (op->pinfo & INSN_TYPE)
{
case INSN_BRANCH:
info->insn_type = dis_branch;
break;
case INSN_CONDBRANCH:
info->insn_type = dis_condbranch;
break;
case INSN_JSR:
info->insn_type = dis_jsr;
break;
case INSN_DREF:
info->insn_type = dis_dref;
break;
default:
break;
}
if (op->pinfo & INSN_DATA_SIZE)
{
int size = ((op->pinfo & INSN_DATA_SIZE)
>> INSN_DATA_SIZE_SHIFT);
info->data_size = 1 << (size - 1);
}
return insnlen;
}
}
/* We did not find a match, so just print the instruction bits. */
info->insn_type = dis_noninsn;
(*info->fprintf_func) (info->stream, "0x%llx", (unsigned long long)word);
return insnlen;
}
int
print_insn_riscv (bfd_vma memaddr, struct disassemble_info *info)
{
bfd_byte packet[2];
insn_t insn = 0;
bfd_vma n;
int status;
if (info->disassembler_options != NULL)
{
parse_riscv_dis_options (info->disassembler_options);
/* Avoid repeatedly parsing the options. */
info->disassembler_options = NULL;
}
else if (riscv_gpr_names == NULL)
set_default_riscv_dis_options ();
/* Instructions are a sequence of 2-byte packets in little-endian order. */
for (n = 0; n < sizeof (insn) && n < riscv_insn_length (insn); n += 2)
{
status = (*info->read_memory_func) (memaddr + n, packet, 2, info);
if (status != 0)
{
/* Don't fail just because we fell off the end. */
if (n > 0)
break;
(*info->memory_error_func) (status, memaddr, info);
return status;
}
insn |= ((insn_t) bfd_getl16 (packet)) << (8 * n);
}
return riscv_disassemble_insn (memaddr, insn, info);
}
/* Prevent use of the fake labels that are generated as part of the DWARF
and for relaxable relocations in the assembler. */
bfd_boolean
riscv_symbol_is_valid (asymbol * sym,
struct disassemble_info * info ATTRIBUTE_UNUSED)
{
const char * name;
if (sym == NULL)
return FALSE;
name = bfd_asymbol_name (sym);
return (strcmp (name, RISCV_FAKE_LABEL_NAME) != 0);
}
void
print_riscv_disassembler_options (FILE *stream)
{
fprintf (stream, _("\n\
The following RISC-V-specific disassembler options are supported for use\n\
with the -M switch (multiple options should be separated by commas):\n"));
fprintf (stream, _("\n\
numeric Print numeric register names, rather than ABI names.\n"));
fprintf (stream, _("\n\
no-aliases Disassemble only into canonical instructions, rather\n\
than into pseudoinstructions.\n"));
fprintf (stream, _("\n"));
}