/* RISC-V disassembler

/* RISC-V disassembler
Copyright (C) 2011-2024 Free Software Foundation, Inc.

Contributed by Andrew Waterman ([email protected]).
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 "elfxx-riscv.h"

#include <stdint.h>
#include <ctype.h>

/* Current XLEN for the disassembler. */
static unsigned xlen = 0;

/* Default ISA specification version (constant as of now). */
static enum riscv_spec_class default_isa_spec = ISA_SPEC_CLASS_DRAFT - 1;

/* Default privileged specification
(as specified by the ELF attributes or the `priv-spec' option). */
static enum riscv_spec_class default_priv_spec = PRIV_SPEC_CLASS_NONE;

static riscv_subset_list_t riscv_subsets;
static riscv_parse_subset_t riscv_rps_dis =
{
&riscv_subsets, /* subset_list. */
opcodes_error_handler,/* error_handler. */
&xlen, /* xlen. */
&default_isa_spec, /* isa_spec. */
false, /* check_unknown_prefixed_ext. */
};

struct riscv_private_data
{
bfd_vma gp;
bfd_vma print_addr;
bfd_vma hi_addr[OP_MASK_RD + 1];
bool to_print_addr;
bool has_gp;
};

/* Used for mapping symbols. */
static int last_map_symbol = -1;
static bfd_vma last_stop_offset = 0;
static bfd_vma last_map_symbol_boundary = 0;
static enum riscv_seg_mstate last_map_state = MAP_NONE;
static asection *last_map_section = NULL;

/* Register names as used by the disassembler. */
static const char (*riscv_gpr_names)[NRC];
static const char (*riscv_fpr_names)[NRC];

/* If set, disassemble as most general instruction. */
static bool no_aliases = false;

/* Set default RISC-V disassembler options. */

static void
set_default_riscv_dis_options (void)
{
riscv_gpr_names = riscv_gpr_names_abi;
riscv_fpr_names = riscv_fpr_names_abi;
no_aliases = false;
}

/* Parse RISC-V disassembler option (without arguments). */

static bool
parse_riscv_dis_option_without_args (const char *option)
{
if (strcmp (option, "no-aliases") == 0)
no_aliases = true;
else if (strcmp (option, "numeric") == 0)
{
riscv_gpr_names = riscv_gpr_names_numeric;
riscv_fpr_names = riscv_fpr_names_numeric;
}
else
return false;
return true;
}

/* Parse RISC-V disassembler option (possibly with arguments). */

static void
parse_riscv_dis_option (const char *option)
{
char *equal, *value;

if (parse_riscv_dis_option_without_args (option))
return;

equal = strchr (option, '=');
if (equal == NULL)
{
/* The option without '=' should be defined above. */
opcodes_error_handler (_("unrecognized disassembler option: %s"), option);
return;
}
if (equal == option
|| *(equal + 1) == '\0')
{
/* Invalid options with '=', no option name before '=',
and no value after '='. */
opcodes_error_handler (_("unrecognized disassembler option with '=': %s"),
option);
return;
}

*equal = '\0';
value = equal + 1;
if (strcmp (option, "priv-spec") == 0)
{
enum riscv_spec_class priv_spec = PRIV_SPEC_CLASS_NONE;
const char *name = NULL;

RISCV_GET_PRIV_SPEC_CLASS (value, priv_spec);
if (priv_spec == PRIV_SPEC_CLASS_NONE)
opcodes_error_handler (_("unknown privileged spec set by %s=%s"),
option, value);
else if (default_priv_spec == PRIV_SPEC_CLASS_NONE)
default_priv_spec = priv_spec;
else if (default_priv_spec != priv_spec)
{
RISCV_GET_PRIV_SPEC_NAME (name, default_priv_spec);
opcodes_error_handler (_("mis-matched privilege spec set by %s=%s, "
"the elf privilege attribute is %s"),
option, value, name);
}
}
else
{
/* xgettext:c-format */
opcodes_error_handler (_("unrecognized disassembler option: %s"), option);
}
}

/* Parse RISC-V disassembler options. */

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_styled_func) (info->stream, dis_style_text, "%s", s);
}

/* If we need to print an address, set its value and state. */

static void
maybe_print_address (struct riscv_private_data *pd, int base_reg, int offset,
int wide)
{
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->has_gp)
pd->print_addr = pd->gp + offset;
else if (base_reg == X_TP || base_reg == 0)
pd->print_addr = offset;
else
return; /* Don't print the address. */
pd->to_print_addr = true;

/* Sign-extend a 32-bit value to a 64-bit value. */
if (wide)
pd->print_addr = (bfd_vma)(int32_t) pd->print_addr;

/* Fit into a 32-bit value on RV32. */
if (xlen == 32)
pd->print_addr = (bfd_vma)(uint32_t)pd->print_addr;
}

/* Print insn arguments for 32/64-bit code. */

static void
print_insn_args (const char *oparg, 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_styled_ftype print = info->fprintf_styled_func;
const char *opargStart;

if (*oparg != '\0')
print (info->stream, dis_style_text, "\t");

for (; *oparg != '\0'; oparg++)
{
opargStart = oparg;
switch (*oparg)
{
case 'C': /* RVC */
switch (*++oparg)
{
case 's': /* RS1 x8-x15. */
case 'w': /* RS1 x8-x15. */
print (info->stream, dis_style_register, "%s",
riscv_gpr_names[EXTRACT_OPERAND (CRS1S, l) + 8]);
break;
case 't': /* RS2 x8-x15. */
case 'x': /* RS2 x8-x15. */
print (info->stream, dis_style_register, "%s",
riscv_gpr_names[EXTRACT_OPERAND (CRS2S, l) + 8]);
break;
case 'U': /* RS1, constrained to equal RD. */
print (info->stream, dis_style_register,
"%s", riscv_gpr_names[rd]);
break;
case 'c': /* RS1, constrained to equal sp. */
print (info->stream, dis_style_register, "%s",
riscv_gpr_names[X_SP]);
break;
case 'V': /* RS2 */
print (info->stream, dis_style_register, "%s",
riscv_gpr_names[EXTRACT_OPERAND (CRS2, l)]);
break;
case 'o':
case 'j':
if (((l & MASK_C_ADDI) == MATCH_C_ADDI) && rd != 0)
maybe_print_address (pd, rd, EXTRACT_CITYPE_IMM (l), 0);
if (info->mach == bfd_mach_riscv64
&& ((l & MASK_C_ADDIW) == MATCH_C_ADDIW) && rd != 0)
maybe_print_address (pd, rd, EXTRACT_CITYPE_IMM (l), 1);
print (info->stream, dis_style_immediate, "%d",
(int)EXTRACT_CITYPE_IMM (l));
break;
case 'k':
print (info->stream, dis_style_address_offset, "%d",
(int)EXTRACT_CLTYPE_LW_IMM (l));
break;
case 'l':
print (info->stream, dis_style_address_offset, "%d",
(int)EXTRACT_CLTYPE_LD_IMM (l));
break;
case 'm':
print (info->stream, dis_style_address_offset, "%d",
(int)EXTRACT_CITYPE_LWSP_IMM (l));
break;
case 'n':
print (info->stream, dis_style_address_offset, "%d",
(int)EXTRACT_CITYPE_LDSP_IMM (l));
break;
case 'K':
print (info->stream, dis_style_immediate, "%d",
(int)EXTRACT_CIWTYPE_ADDI4SPN_IMM (l));
break;
case 'L':
print (info->stream, dis_style_immediate, "%d",
(int)EXTRACT_CITYPE_ADDI16SP_IMM (l));
break;
case 'M':
print (info->stream, dis_style_address_offset, "%d",
(int)EXTRACT_CSSTYPE_SWSP_IMM (l));
break;
case 'N':
print (info->stream, dis_style_address_offset, "%d",
(int)EXTRACT_CSSTYPE_SDSP_IMM (l));
break;
case 'p':
info->target = EXTRACT_CBTYPE_IMM (l) + pc;
(*info->print_address_func) (info->target, info);
break;
case 'a':
info->target = EXTRACT_CJTYPE_IMM (l) + pc;
(*info->print_address_func) (info->target, info);
break;
case 'u':
print (info->stream, dis_style_immediate, "0x%x",
(unsigned)(EXTRACT_CITYPE_IMM (l) & (RISCV_BIGIMM_REACH-1)));
break;
case '>':
print (info->stream, dis_style_immediate, "0x%x",
(unsigned)EXTRACT_CITYPE_IMM (l) & 0x3f);
break;
case '<':
print (info->stream, dis_style_immediate, "0x%x",
(unsigned)EXTRACT_CITYPE_IMM (l) & 0x1f);
break;
case 'T': /* Floating-point RS2. */
print (info->stream, dis_style_register, "%s",
riscv_fpr_names[EXTRACT_OPERAND (CRS2, l)]);
break;
case 'D': /* Floating-point RS2 x8-x15. */
print (info->stream, dis_style_register, "%s",
riscv_fpr_names[EXTRACT_OPERAND (CRS2S, l) + 8]);
break;
}
break;

case 'V': /* RVV */
switch (*++oparg)
{
case 'd':
case 'f':
print (info->stream, dis_style_register, "%s",
riscv_vecr_names_numeric[EXTRACT_OPERAND (VD, l)]);
break;
case 'e':
if (!EXTRACT_OPERAND (VWD, l))
print (info->stream, dis_style_register, "%s",
riscv_gpr_names[0]);
else
print (info->stream, dis_style_register, "%s",
riscv_vecr_names_numeric[EXTRACT_OPERAND (VD, l)]);
break;
case 's':
print (info->stream, dis_style_register, "%s",
riscv_vecr_names_numeric[EXTRACT_OPERAND (VS1, l)]);
break;
case 't':
case 'u': /* VS1 == VS2 already verified at this point. */
case 'v': /* VD == VS1 == VS2 already verified at this point. */
print (info->stream, dis_style_register, "%s",
riscv_vecr_names_numeric[EXTRACT_OPERAND (VS2, l)]);
break;
case '0':
print (info->stream, dis_style_register, "%s",
riscv_vecr_names_numeric[0]);
break;
case 'b':
case 'c':
{
int imm = (*oparg == 'b') ? EXTRACT_RVV_VB_IMM (l)
: EXTRACT_RVV_VC_IMM (l);
unsigned int imm_vlmul = EXTRACT_OPERAND (VLMUL, imm);
unsigned int imm_vsew = EXTRACT_OPERAND (VSEW, imm);
unsigned int imm_vta = EXTRACT_OPERAND (VTA, imm);
unsigned int imm_vma = EXTRACT_OPERAND (VMA, imm);
unsigned int imm_vtype_res = (imm >> 8);

if (imm_vsew < ARRAY_SIZE (riscv_vsew)
&& imm_vlmul < ARRAY_SIZE (riscv_vlmul)
&& imm_vta < ARRAY_SIZE (riscv_vta)
&& imm_vma < ARRAY_SIZE (riscv_vma)
&& !imm_vtype_res
&& riscv_vsew[imm_vsew] != NULL
&& riscv_vlmul[imm_vlmul] != NULL)
print (info->stream, dis_style_text, "%s,%s,%s,%s",
riscv_vsew[imm_vsew],
riscv_vlmul[imm_vlmul], riscv_vta[imm_vta],
riscv_vma[imm_vma]);
else
print (info->stream, dis_style_immediate, "%d", imm);
}
break;
case 'i':
print (info->stream, dis_style_immediate, "%d",
(int)EXTRACT_RVV_VI_IMM (l));
break;
case 'j':
print (info->stream, dis_style_immediate, "%d",
(int)EXTRACT_RVV_VI_UIMM (l));
break;
case 'k':
print (info->stream, dis_style_immediate, "%d",
(int)EXTRACT_RVV_OFFSET (l));
break;
case 'l':
print (info->stream, dis_style_immediate, "%d",
(int)EXTRACT_RVV_VI_UIMM6 (l));
break;
case 'm':
if (!EXTRACT_OPERAND (VMASK, l))
{
print (info->stream, dis_style_text, ",");
print (info->stream, dis_style_register, "%s",
riscv_vecm_names_numeric[0]);
}
break;
}
break;

case ',':
case '(':
case ')':
case '[':
case ']':
print (info->stream, dis_style_text, "%c", *oparg);
break;

case '0':
/* Only print constant 0 if it is the last argument. */
if (!oparg[1])
print (info->stream, dis_style_immediate, "0");
break;

case 's':
if ((l & MASK_JALR) == MATCH_JALR)
maybe_print_address (pd, rs1, EXTRACT_ITYPE_IMM (l), 0);
print (info->stream, dis_style_register, "%s", riscv_gpr_names[rs1]);
break;

case 't':
print (info->stream, dis_style_register, "%s",
riscv_gpr_names[EXTRACT_OPERAND (RS2, l)]);
break;

case 'u':
print (info->stream, dis_style_immediate, "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), 0);
/* 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), 0);
if (info->mach == bfd_mach_riscv64
&& ((l & MASK_ADDIW) == MATCH_ADDIW) && rs1 != 0)
maybe_print_address (pd, rs1, EXTRACT_ITYPE_IMM (l), 1);
print (info->stream, dis_style_immediate, "%d",
(int)EXTRACT_ITYPE_IMM (l));
break;

case 'q':
maybe_print_address (pd, rs1, EXTRACT_STYPE_IMM (l), 0);
print (info->stream, dis_style_address_offset, "%d",
(int)EXTRACT_STYPE_IMM (l));
break;

case 'a':
info->target = EXTRACT_JTYPE_IMM (l) + pc;
(*info->print_address_func) (info->target, info);
break;

case 'p':
info->target = EXTRACT_BTYPE_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_CITYPE_LUI_IMM (l);
print (info->stream, dis_style_register, "%s", riscv_gpr_names[rd]);
break;

case 'y':
print (info->stream, dis_style_immediate, "0x%x",
EXTRACT_OPERAND (BS, l));
break;

case 'z':
print (info->stream, dis_style_register, "%s", riscv_gpr_names[0]);
break;

case '>':
print (info->stream, dis_style_immediate, "0x%x",
EXTRACT_OPERAND (SHAMT, l));
break;

case '<':
print (info->stream, dis_style_immediate, "0x%x",
EXTRACT_OPERAND (SHAMTW, l));
break;

case 'S':
case 'U':
print (info->stream, dis_style_register, "%s", riscv_fpr_names[rs1]);
break;

case 'T':
print (info->stream, dis_style_register, "%s",
riscv_fpr_names[EXTRACT_OPERAND (RS2, l)]);
break;

case 'D':
print (info->stream, dis_style_register, "%s", riscv_fpr_names[rd]);
break;

case 'R':
print (info->stream, dis_style_register, "%s",
riscv_fpr_names[EXTRACT_OPERAND (RS3, l)]);
break;

case 'E':
{
static const char *riscv_csr_hash[4096]; /* Total 2^12 CSRs. */
static bool init_csr = false;
unsigned int csr = EXTRACT_OPERAND (CSR, l);

if (!init_csr)
{
unsigned int i;
for (i = 0; i < 4096; i++)
riscv_csr_hash[i] = NULL;

/* Set to the newest privileged version. */
if (default_priv_spec == PRIV_SPEC_CLASS_NONE)
default_priv_spec = PRIV_SPEC_CLASS_DRAFT - 1;

#define DECLARE_CSR(name, num, class, define_version, abort_version) \
if (riscv_csr_hash[num] == NULL \
&& ((define_version == PRIV_SPEC_CLASS_NONE \
&& abort_version == PRIV_SPEC_CLASS_NONE) \
|| (default_priv_spec >= define_version \
&& default_priv_spec < abort_version))) \
riscv_csr_hash[num] = #name;
#define DECLARE_CSR_ALIAS(name, num, class, define_version, abort_version) \
DECLARE_CSR (name, num, class, define_version, abort_version)
#include "opcode/riscv-opc.h"
#undef DECLARE_CSR
}

if (riscv_csr_hash[csr] != NULL)
if (riscv_subset_supports (&riscv_rps_dis, "xtheadvector")
&& (csr == CSR_VSTART
|| csr == CSR_VXSAT
|| csr == CSR_VXRM
|| csr == CSR_VL
|| csr == CSR_VTYPE
|| csr == CSR_VLENB))
print (info->stream, dis_style_register, "%s",
concat ("th.", riscv_csr_hash[csr], NULL));
else
print (info->stream, dis_style_register, "%s",
riscv_csr_hash[csr]);
else
print (info->stream, dis_style_immediate, "0x%x", csr);
break;
}

case 'Y':
print (info->stream, dis_style_immediate, "0x%x",
EXTRACT_OPERAND (RNUM, l));
break;

case 'Z':
print (info->stream, dis_style_immediate, "%d", rs1);
break;

case 'W': /* Various operands for standard z extensions. */
switch (*++oparg)
{
case 'i':
switch (*++oparg)
{
case 'f':
print (info->stream, dis_style_address_offset, "%d",
(int) EXTRACT_STYPE_IMM (l));
break;
default:
goto undefined_modifier;
}
break;
case 'f':
switch (*++oparg)
{
case 'v':
if (riscv_fli_symval[rs1])
print (info->stream, dis_style_text, "%s",
riscv_fli_symval[rs1]);
else
print (info->stream, dis_style_immediate, "%a",
riscv_fli_numval[rs1]);
break;
default:
goto undefined_modifier;
}
break;
case 'c': /* Zcb extension 16 bits length instruction fields. */
switch (*++oparg)
{
case 'b':
print (info->stream, dis_style_immediate, "%d",
(int)EXTRACT_ZCB_BYTE_UIMM (l));
break;
case 'h':
print (info->stream, dis_style_immediate, "%d",
(int)EXTRACT_ZCB_HALFWORD_UIMM (l));
break;
default:
goto undefined_modifier;
}
break;
default:
goto undefined_modifier;
}
break;

case 'X': /* Vendor-specific operands. */
switch (*++oparg)
{
case 't': /* Vendor-specific (T-head) operands. */
{
size_t n;
size_t s;
bool sign;
switch (*++oparg)
{
case 'V':
++oparg;
if (*oparg != 'c')
goto undefined_modifier;

int imm = (*oparg == 'b') ? EXTRACT_RVV_VB_IMM (l)
: EXTRACT_RVV_VC_IMM (l);
unsigned int imm_vediv = EXTRACT_OPERAND (XTHEADVEDIV, imm);
unsigned int imm_vlmul = EXTRACT_OPERAND (XTHEADVLMUL, imm);
unsigned int imm_vsew = EXTRACT_OPERAND (XTHEADVSEW, imm);
unsigned int imm_vtype_res
= EXTRACT_OPERAND (XTHEADVTYPE_RES, imm);
if (imm_vsew < ARRAY_SIZE (riscv_vsew)
&& imm_vlmul < ARRAY_SIZE (riscv_th_vlen)
&& imm_vediv < ARRAY_SIZE (riscv_th_vediv)
&& ! imm_vtype_res)
print (info->stream, dis_style_text, "%s,%s,%s",
riscv_vsew[imm_vsew], riscv_th_vlen[imm_vlmul],
riscv_th_vediv[imm_vediv]);
else
print (info->stream, dis_style_immediate, "%d", imm);
break;
case 'l': /* Integer immediate, literal. */
oparg++;
while (*oparg && *oparg != ',')
{
print (info->stream, dis_style_immediate, "%c", *oparg);
oparg++;
}
oparg--;
break;
case 's': /* Integer immediate, 'XsN@S' ... N-bit signed immediate at bit S. */
sign = true;
goto print_imm;
case 'u': /* Integer immediate, 'XuN@S' ... N-bit unsigned immediate at bit S. */
sign = false;
goto print_imm;
print_imm:
n = strtol (oparg + 1, (char **)&oparg, 10);
if (*oparg != '@')
goto undefined_modifier;
s = strtol (oparg + 1, (char **)&oparg, 10);
oparg--;

if (!sign)
print (info->stream, dis_style_immediate, "%lu",
(unsigned long)EXTRACT_U_IMM (n, s, l));
else
print (info->stream, dis_style_immediate, "%li",
(signed long)EXTRACT_S_IMM (n, s, l));
break;
default:
goto undefined_modifier;
}
}
break;
case 'c': /* Vendor-specific (CORE-V) operands. */
switch (*++oparg)
{
case '2':
print (info->stream, dis_style_immediate, "%d",
((int) EXTRACT_CV_IS2_UIMM5 (l)));
break;
case '3':
print (info->stream, dis_style_immediate, "%d",
((int) EXTRACT_CV_IS3_UIMM5 (l)));
break;
default:
goto undefined_modifier;
}
break;
case 's': /* Vendor-specific (SiFive) operands. */
switch (*++oparg)
{
/* SiFive vector coprocessor interface. */
case 'd':
print (info->stream, dis_style_register, "0x%x",
(unsigned) EXTRACT_OPERAND (RD, l));
break;
case 't':
print (info->stream, dis_style_register, "0x%x",
(unsigned) EXTRACT_OPERAND (RS2, l));
break;
case 'O':
switch (*++oparg)
{
case '2':
print (info->stream, dis_style_register, "0x%x",
(unsigned) EXTRACT_OPERAND (XSO2, l));
break;
case '1':
print (info->stream, dis_style_register, "0x%x",
(unsigned) EXTRACT_OPERAND (XSO1, l));
break;
}
break;
}
break;
default:
goto undefined_modifier;
}
break;

default:
undefined_modifier:
/* xgettext:c-format */
print (info->stream, dis_style_text,
_("# internal error, undefined modifier (%c)"),
*opargStart);
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,
const bfd_byte *packet,
disassemble_info *info)
{
const struct riscv_opcode *op;
static bool init = false;
static const struct riscv_opcode *riscv_hash[OP_MASK_OP + 1];
struct riscv_private_data *pd = info->private_data;
int insnlen, i;
bool printed;

#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 = true;
}

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)
{
/* 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;
}

/* If arch has the Zfinx extension, replace FPR with GPR. */
if (riscv_subset_supports (&riscv_rps_dis, "zfinx"))
riscv_fpr_names = riscv_gpr_names;
else
riscv_fpr_names = riscv_gpr_names == riscv_gpr_names_abi ?
riscv_fpr_names_abi : riscv_fpr_names_numeric;

for (; op->name; op++)
{
/* Ignore macro insns. */
if (op->pinfo == INSN_MACRO)
continue;
/* 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;
/* Is this instruction supported by the current architecture? */
if (!riscv_multi_subset_supports (&riscv_rps_dis, op->insn_class))
continue;

/* It's a match. */
(*info->fprintf_styled_func) (info->stream, dis_style_mnemonic,
"%s", op->name);
print_insn_args (op->args, word, memaddr, info);

/* Try to disassemble multi-instruction addressing sequences. */
if (pd->to_print_addr)
{
info->target = pd->print_addr;
(*info->fprintf_styled_func)
(info->stream, dis_style_comment_start, " # ");
(*info->print_address_func) (info->target, info);
pd->to_print_addr = false;
}

/* 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 in
the shape of an assembler .insn directive. */
info->insn_type = dis_noninsn;
(*info->fprintf_styled_func)
(info->stream, dis_style_assembler_directive, ".insn");
(*info->fprintf_styled_func) (info->stream, dis_style_text, "\t");
(*info->fprintf_styled_func) (info->stream, dis_style_immediate,
"%d", insnlen);
(*info->fprintf_styled_func) (info->stream, dis_style_text, ", ");
(*info->fprintf_styled_func) (info->stream, dis_style_immediate, "0x");
for (i = insnlen, printed = false; i >= 2; )
{
i -= 2;
word = bfd_get_bits (packet + i, 16, false);
if (!word && !printed)
continue;

(*info->fprintf_styled_func) (info->stream, dis_style_immediate,
"%04x", (unsigned int) word);
printed = true;
}

return insnlen;
}

/* If we find the suitable mapping symbol update the STATE.
Otherwise, do nothing. */

static void
riscv_update_map_state (int n,
enum riscv_seg_mstate *state,
struct disassemble_info *info)
{
const char *name;

/* If the symbol is in a different section, ignore it. */
if (info->section != NULL
&& info->section != info->symtab[n]->section)
return;

name = bfd_asymbol_name(info->symtab[n]);
if (strcmp (name, "$x") == 0)
*state = MAP_INSN;
else if (strcmp (name, "$d") == 0)
*state = MAP_DATA;
else if (strncmp (name, "$xrv", 4) == 0)
{
*state = MAP_INSN;
riscv_release_subset_list (&riscv_subsets);

/* ISA mapping string may be numbered, suffixed with '.n'. Do not
consider this as part of the ISA string. */
char *suffix = strchr (name, '.');
if (suffix)
{
int suffix_index = (int)(suffix - name);
char *name_substr = xmalloc (suffix_index + 1);
strncpy (name_substr, name, suffix_index);
name_substr[suffix_index] = '\0';
riscv_parse_subset (&riscv_rps_dis, name_substr + 2);
free (name_substr);
}
else
riscv_parse_subset (&riscv_rps_dis, name + 2);
}
}

/* Return true if we find the suitable mapping symbol.
Otherwise, return false. */

static bool
riscv_is_valid_mapping_symbol (int n,
struct disassemble_info *info)
{
const char *name;

/* If the symbol is in a different section, ignore it. */
if (info->section != NULL
&& info->section != info->symtab[n]->section)
return false;

name = bfd_asymbol_name(info->symtab[n]);
return riscv_elf_is_mapping_symbols (name);
}

/* Check the sorted symbol table (sorted by the symbol value), find the
suitable mapping symbols. */

static enum riscv_seg_mstate
riscv_search_mapping_symbol (bfd_vma memaddr,
struct disassemble_info *info)
{
enum riscv_seg_mstate mstate;
bool from_last_map_symbol;
bool found = false;
int symbol = -1;
int n;

/* Return the last map state if the address is still within the range of the
last mapping symbol. */
if (last_map_section == info->section
&& (memaddr < last_map_symbol_boundary))
return last_map_state;

last_map_section = info->section;

/* Decide whether to print the data or instruction by default, in case
we can not find the corresponding mapping symbols. */
mstate = MAP_DATA;
if ((info->section
&& info->section->flags & SEC_CODE)
|| !info->section)
mstate = MAP_INSN;

if (info->symtab_size == 0
|| bfd_asymbol_flavour (*info->symtab) != bfd_target_elf_flavour)
return mstate;

/* Reset the last_map_symbol if we start to dump a new section. */
if (memaddr <= 0)
last_map_symbol = -1;

/* If the last stop offset is different from the current one, then
don't use the last_map_symbol to search. We usually reset the
info->stop_offset when handling a new section. */
from_last_map_symbol = (last_map_symbol >= 0
&& info->stop_offset == last_stop_offset);

/* Start scanning at the start of the function, or wherever
we finished last time. */
n = info->symtab_pos + 1;
if (from_last_map_symbol && n >= last_map_symbol)
n = last_map_symbol;

/* Find the suitable mapping symbol to dump. */
for (; n < info->symtab_size; n++)
{
bfd_vma addr = bfd_asymbol_value (info->symtab[n]);
/* We have searched all possible symbols in the range. */
if (addr > memaddr)
break;
if (riscv_is_valid_mapping_symbol (n, info))
{
symbol = n;
found = true;
/* Do not stop searching, in case there are some mapping
symbols have the same value, but have different names.
Use the last one. */
}
}

/* We can not find the suitable mapping symbol above. Therefore, we
look forwards and try to find it again, but don't go past the start
of the section. Otherwise a data section without mapping symbols
can pick up a text mapping symbol of a preceeding section. */
if (!found)
{
n = info->symtab_pos;
if (from_last_map_symbol && n >= last_map_symbol)
n = last_map_symbol;

for (; n >= 0; n--)
{
bfd_vma addr = bfd_asymbol_value (info->symtab[n]);
/* We have searched all possible symbols in the range. */
if (addr < (info->section ? info->section->vma : 0))
break;
/* Stop searching once we find the closed mapping symbol. */
if (riscv_is_valid_mapping_symbol (n, info))
{
symbol = n;
found = true;
break;
}
}
}

if (found)
{
riscv_update_map_state (symbol, &mstate, info);

/* Find the next mapping symbol to determine the boundary of this mapping
symbol. */

bool found_next = false;
/* Try to found next mapping symbol. */
for (n = symbol + 1; n < info->symtab_size; n++)
{
if (info->symtab[symbol]->section != info->symtab[n]->section)
continue;

bfd_vma addr = bfd_asymbol_value (info->symtab[n]);
const char *sym_name = bfd_asymbol_name(info->symtab[n]);
if (sym_name[0] == '$' && (sym_name[1] == 'x' || sym_name[1] == 'd'))
{
/* The next mapping symbol has been found, and it represents the
boundary of this mapping symbol. */
found_next = true;
last_map_symbol_boundary = addr;
break;
}
}

/* No further mapping symbol has been found, indicating that the boundary
of the current mapping symbol is the end of this section. */
if (!found_next)
last_map_symbol_boundary = info->section->vma + info->section->size;
}

/* Save the information for next use. */
last_map_symbol = symbol;
last_stop_offset = info->stop_offset;

return mstate;
}

/* Decide which data size we should print. */

static bfd_vma
riscv_data_length (bfd_vma memaddr,
disassemble_info *info)
{
bfd_vma length;
bool found = false;

length = 4;
if (info->symtab_size != 0
&& bfd_asymbol_flavour (*info->symtab) == bfd_target_elf_flavour
&& last_map_symbol >= 0)
{
int n;
enum riscv_seg_mstate m = MAP_NONE;
for (n = last_map_symbol + 1; n < info->symtab_size; n++)
{
bfd_vma addr = bfd_asymbol_value (info->symtab[n]);
if (addr > memaddr
&& riscv_is_valid_mapping_symbol (n, info))
{
if (addr - memaddr < length)
length = addr - memaddr;
found = true;
riscv_update_map_state (n, &m, info);
break;
}
}
}
if (!found)
{
/* Do not set the length which exceeds the section size. */
bfd_vma offset = info->section->vma + info->section->size;
offset -= memaddr;
length = (offset < length) ? offset : length;
}
length = length == 3 ? 2 : length;
return length;
}

/* Dump the data contents. */

static int
riscv_disassemble_data (bfd_vma memaddr ATTRIBUTE_UNUSED,
insn_t data,
const bfd_byte *packet ATTRIBUTE_UNUSED,
disassemble_info *info)
{
info->display_endian = info->endian;

switch (info->bytes_per_chunk)
{
case 1:
info->bytes_per_line = 6;
(*info->fprintf_styled_func)
(info->stream, dis_style_assembler_directive, ".byte");
(*info->fprintf_styled_func) (info->stream, dis_style_text, "\t");
(*info->fprintf_styled_func) (info->stream, dis_style_immediate,
"0x%02x", (unsigned)data);
break;
case 2:
info->bytes_per_line = 8;
(*info->fprintf_styled_func)
(info->stream, dis_style_assembler_directive, ".short");
(*info->fprintf_styled_func) (info->stream, dis_style_text, "\t");
(*info->fprintf_styled_func)
(info->stream, dis_style_immediate, "0x%04x", (unsigned) data);
break;
case 4:
info->bytes_per_line = 8;
(*info->fprintf_styled_func)
(info->stream, dis_style_assembler_directive, ".word");
(*info->fprintf_styled_func) (info->stream, dis_style_text, "\t");
(*info->fprintf_styled_func)
(info->stream, dis_style_immediate, "0x%08lx",
(unsigned long) data);
break;
case 8:
info->bytes_per_line = 8;
(*info->fprintf_styled_func)
(info->stream, dis_style_assembler_directive, ".dword");
(*info->fprintf_styled_func) (info->stream, dis_style_text, "\t");
(*info->fprintf_styled_func)
(info->stream, dis_style_immediate, "0x%016llx",
(unsigned long long) data);
break;
default:
abort ();
}
return info->bytes_per_chunk;
}

static bool
riscv_init_disasm_info (struct disassemble_info *info)
{
int i;

struct riscv_private_data *pd =
xcalloc (1, sizeof (struct riscv_private_data));
pd->gp = 0;
pd->print_addr = 0;
for (i = 0; i < (int) ARRAY_SIZE (pd->hi_addr); i++)
pd->hi_addr[i] = -1;
pd->to_print_addr = false;
pd->has_gp = false;

for (i = 0; i < info->symtab_size; i++)
{
asymbol *sym = info->symtab[i];
if (strcmp (bfd_asymbol_name (sym), RISCV_GP_SYMBOL) == 0)
{
pd->gp = bfd_asymbol_value (sym);
pd->has_gp = true;
}
}

info->private_data = pd;
return true;
}

int
print_insn_riscv (bfd_vma memaddr, struct disassemble_info *info)
{
bfd_byte packet[RISCV_MAX_INSN_LEN];
insn_t insn = 0;
bfd_vma dump_size;
int status;
enum riscv_seg_mstate mstate;
int (*riscv_disassembler) (bfd_vma, insn_t, const bfd_byte *,
struct disassemble_info *);

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 ();

if (info->private_data == NULL && !riscv_init_disasm_info (info))
return -1;

mstate = riscv_search_mapping_symbol (memaddr, info);
/* Save the last mapping state. */
last_map_state = mstate;

/* Set the size to dump. */
if (mstate == MAP_DATA
&& (info->flags & DISASSEMBLE_DATA) == 0)
{
dump_size = riscv_data_length (memaddr, info);
info->bytes_per_chunk = dump_size;
riscv_disassembler = riscv_disassemble_data;
}
else
{
/* Get the first 2-bytes to check the lenghth of instruction. */
status = (*info->read_memory_func) (memaddr, packet, 2, info);
if (status != 0)
{
(*info->memory_error_func) (status, memaddr, info);
return -1;
}
insn = (insn_t) bfd_getl16 (packet);
dump_size = riscv_insn_length (insn);
riscv_disassembler = riscv_disassemble_insn;
}

/* Fetch the instruction to dump. */
status = (*info->read_memory_func) (memaddr, packet, dump_size, info);
if (status != 0)
{
(*info->memory_error_func) (status, memaddr, info);
return -1;
}
insn = (insn_t) bfd_get_bits (packet, dump_size * 8, false);

return (*riscv_disassembler) (memaddr, insn, packet, info);
}

disassembler_ftype
riscv_get_disassembler (bfd *abfd)
{
const char *default_arch = "rv64gc";

if (abfd && bfd_get_flavour (abfd) == bfd_target_elf_flavour)
{
const char *sec_name = get_elf_backend_data (abfd)->obj_attrs_section;
if (bfd_get_section_by_name (abfd, sec_name) != NULL)
{
obj_attribute *attr = elf_known_obj_attributes_proc (abfd);
unsigned int Tag_a = Tag_RISCV_priv_spec;
unsigned int Tag_b = Tag_RISCV_priv_spec_minor;
unsigned int Tag_c = Tag_RISCV_priv_spec_revision;
riscv_get_priv_spec_class_from_numbers (attr[Tag_a].i,
attr[Tag_b].i,
attr[Tag_c].i,
&default_priv_spec);
default_arch = attr[Tag_RISCV_arch].s;
}
}

riscv_release_subset_list (&riscv_subsets);
riscv_parse_subset (&riscv_rps_dis, default_arch);
return print_insn_riscv;
}

/* Prevent use of the fake labels that are generated as part of the DWARF
and for relaxable relocations in the assembler. */

bool
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
&& !riscv_elf_is_mapping_symbols (name));
}

/* Indices into option argument vector for options accepting an argument.
Use RISCV_OPTION_ARG_NONE for options accepting no argument. */

typedef enum
{
RISCV_OPTION_ARG_NONE = -1,
RISCV_OPTION_ARG_PRIV_SPEC,

RISCV_OPTION_ARG_COUNT
} riscv_option_arg_t;

/* Valid RISCV disassembler options. */

static struct
{
const char *name;
const char *description;
riscv_option_arg_t arg;
} riscv_options[] =
{
{ "numeric",
N_("Print numeric register names, rather than ABI names."),
RISCV_OPTION_ARG_NONE },
{ "no-aliases",
N_("Disassemble only into canonical instructions."),
RISCV_OPTION_ARG_NONE },
{ "priv-spec=",
N_("Print the CSR according to the chosen privilege spec."),
RISCV_OPTION_ARG_PRIV_SPEC }
};

/* Build the structure representing valid RISCV disassembler options.
This is done dynamically for maintenance ease purpose; a static
initializer would be unreadable. */

const disasm_options_and_args_t *
disassembler_options_riscv (void)
{
static disasm_options_and_args_t *opts_and_args;

if (opts_and_args == NULL)
{
size_t num_options = ARRAY_SIZE (riscv_options);
size_t num_args = RISCV_OPTION_ARG_COUNT;
disasm_option_arg_t *args;
disasm_options_t *opts;
size_t i, priv_spec_count;

args = XNEWVEC (disasm_option_arg_t, num_args + 1);

args[RISCV_OPTION_ARG_PRIV_SPEC].name = "SPEC";
priv_spec_count = PRIV_SPEC_CLASS_DRAFT - PRIV_SPEC_CLASS_NONE - 1;
args[RISCV_OPTION_ARG_PRIV_SPEC].values
= XNEWVEC (const char *, priv_spec_count + 1);
for (i = 0; i < priv_spec_count; i++)
args[RISCV_OPTION_ARG_PRIV_SPEC].values[i]
= riscv_priv_specs[i].name;
/* The array we return must be NULL terminated. */
args[RISCV_OPTION_ARG_PRIV_SPEC].values[i] = NULL;

/* The array we return must be NULL terminated. */
args[num_args].name = NULL;
args[num_args].values = NULL;

opts_and_args = XNEW (disasm_options_and_args_t);
opts_and_args->args = args;

opts = &opts_and_args->options;
opts->name = XNEWVEC (const char *, num_options + 1);
opts->description = XNEWVEC (const char *, num_options + 1);
opts->arg = XNEWVEC (const disasm_option_arg_t *, num_options + 1);
for (i = 0; i < num_options; i++)
{
opts->name[i] = riscv_options[i].name;
opts->description[i] = _(riscv_options[i].description);
if (riscv_options[i].arg != RISCV_OPTION_ARG_NONE)
opts->arg[i] = &args[riscv_options[i].arg];
else
opts->arg[i] = NULL;
}
/* The array we return must be NULL terminated. */
opts->name[i] = NULL;
opts->description[i] = NULL;
opts->arg[i] = NULL;
}

return opts_and_args;
}

void
print_riscv_disassembler_options (FILE *stream)
{
const disasm_options_and_args_t *opts_and_args;
const disasm_option_arg_t *args;
const disasm_options_t *opts;
size_t max_len = 0;
size_t i;
size_t j;

opts_and_args = disassembler_options_riscv ();
opts = &opts_and_args->options;
args = opts_and_args->args;

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");

/* Compute the length of the longest option name. */
for (i = 0; opts->name[i] != NULL; i++)
{
size_t len = strlen (opts->name[i]);

if (opts->arg[i] != NULL)
len += strlen (opts->arg[i]->name);
if (max_len < len)
max_len = len;
}

for (i = 0, max_len++; opts->name[i] != NULL; i++)
{
fprintf (stream, " %s", opts->name[i]);
if (opts->arg[i] != NULL)
fprintf (stream, "%s", opts->arg[i]->name);
if (opts->description[i] != NULL)
{
size_t len = strlen (opts->name[i]);

if (opts->arg != NULL && opts->arg[i] != NULL)
len += strlen (opts->arg[i]->name);
fprintf (stream, "%*c %s", (int) (max_len - len), ' ',
opts->description[i]);
}
fprintf (stream, "\n");
}

for (i = 0; args[i].name != NULL; i++)
{
if (args[i].values == NULL)
continue;
fprintf (stream, _("\n\
For the options above, the following values are supported for \"%s\":\n "),
args[i].name);
for (j = 0; args[i].values[j] != NULL; j++)
fprintf (stream, " %s", args[i].values[j]);
fprintf (stream, _("\n"));
}

fprintf (stream, _("\n"));
}

void disassemble_free_riscv (struct disassemble_info *info ATTRIBUTE_UNUSED)
{
riscv_release_subset_list (&riscv_subsets);
}