/* tc-loongarch.c -- Assemble for the LoongArch ISA

   Copyright (C) 2021-2022 Free Software Foundation, Inc.
   Contributed by Loongson Ltd.

   This file is part of GAS.

   GAS 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.

   GAS 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 "as.h"
#include "dw2gencfi.h"
#include "loongarch-lex.h"
#include "elf/loongarch.h"
#include "opcode/loongarch.h"
#include "obj-elf.h"
#include "bfd/elfxx-loongarch.h"
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <assert.h>

/* All information about an instruction during assemble.  */
struct loongarch_cl_insn
{
  /* First split string.  */
  const char *name;
  const char *arg_strs[MAX_ARG_NUM_PLUS_2];
  size_t arg_num;

  /* Second analyze name_str and each actual args string to match the insn
     in 'loongarch-opc.c'. And actual args may need be relocated.
     We get length of insn.  If 'insn_length == 0 && insn_mo->macro != NULL',
     it's a macro insntruction and we call 'md_assemble' recursively
     after expanding it.  */
  int match_now;
  int all_match;

  const struct loongarch_opcode *insn;
  size_t insn_length;

  offsetT args[MAX_ARG_NUM_PLUS_2];
  struct reloc_info reloc_info[MAX_RELOC_NUMBER_A_INSN];
  size_t reloc_num;

  /* For relax reserved.  We not support relax now.
     'insn_length < relax_max_length' means need to relax.
     And 'insn_length == relax_max_length' means no need to relax.  */
  size_t relax_max_length;
  relax_substateT subtype;

  /* Then we get the binary representation of insn
     and write it in to section.  */
  insn_t insn_bin;

  /* The frag that contains the instruction.  */
  struct frag *frag;
  /* The offset into FRAG of the first instruction byte.  */
  long where;
  /* The relocs associated with the instruction, if any.  */
  fixS *fixp[MAX_RELOC_NUMBER_A_INSN];
};

#ifndef DEFAULT_ARCH
#define DEFAULT_ARCH "loongarch64"
#endif

/* This array holds the chars that always start a comment.  If the
   pre-processor is disabled, these aren't very useful.  */
const char comment_chars[] = "#";

/* This array holds the chars that only start a comment at the beginning of
   a line.  If the line seems to have the form '# 123 filename'
   .line and .file directives will appear in the pre-processed output.  */
/* Note that input_file.c hand checks for '#' at the beginning of the
   first line of the input file.  This is because the compiler outputs
   #NO_APP at the beginning of its output.  */
/* Also note that C style comments are always supported.  */
const char line_comment_chars[] = "#";

/* This array holds machine specific line separator characters.  */
const char line_separator_chars[] = ";";

/* Chars that can be used to separate mant from exp in floating point nums.  */
const char EXP_CHARS[] = "eE";

/* Chars that mean this number is a floating point constant.  */
/* As in 0f12.456.  */
/* or    0d1.2345e12.  */
const char FLT_CHARS[] = "rRsSfFdDxXpP";

const char *md_shortopts = "O::g::G:";

static const char default_arch[] = DEFAULT_ARCH;

enum options
{
  OPTION_IGNORE = OPTION_MD_BASE,

  OPTION_ABI,
  OPTION_FLOAT_ABI,

  OPTION_FLOAT_ISA,

  OPTION_LA_LOCAL_WITH_ABS,
  OPTION_LA_GLOBAL_WITH_PCREL,
  OPTION_LA_GLOBAL_WITH_ABS,

  OPTION_END_OF_ENUM,
};

struct option md_longopts[] =
{
  { "mabi", required_argument, NULL, OPTION_ABI },

  { "mfpu", required_argument, NULL, OPTION_FLOAT_ISA },

  { "mla-local-with-abs", no_argument, NULL, OPTION_LA_LOCAL_WITH_ABS },
  { "mla-global-with-pcrel", no_argument, NULL, OPTION_LA_GLOBAL_WITH_PCREL },
  { "mla-global-with-abs", no_argument, NULL, OPTION_LA_GLOBAL_WITH_ABS },

  { NULL, no_argument, NULL, 0 }
};

size_t md_longopts_size = sizeof (md_longopts);

int
md_parse_option (int c, const char *arg)
{
  int ret = 1;
  char lp64[256] = "";
  char ilp32[256] = "";
  unsigned char *suf = (unsigned char *)arg;

  lp64['s'] = lp64['S'] = EF_LOONGARCH_ABI_SOFT_FLOAT;
  lp64['f'] = lp64['F'] = EF_LOONGARCH_ABI_SINGLE_FLOAT;
  lp64['d'] = lp64['D'] = EF_LOONGARCH_ABI_DOUBLE_FLOAT;

  ilp32['s'] = ilp32['S'] = EF_LOONGARCH_ABI_SOFT_FLOAT;
  ilp32['f'] = ilp32['F'] = EF_LOONGARCH_ABI_SINGLE_FLOAT;
  ilp32['d'] = ilp32['D'] = EF_LOONGARCH_ABI_DOUBLE_FLOAT;

  switch (c)
    {
    case OPTION_ABI:
      if (strncasecmp (arg, "lp64", 4) == 0 && lp64[suf[4]] != 0)
	{
	  LARCH_opts.ase_ilp32 = 1;
	  LARCH_opts.ase_lp64 = 1;
	  LARCH_opts.ase_abi = lp64[suf[4]];
	}
      else if (strncasecmp (arg, "ilp32", 5) == 0 && ilp32[suf[5]] != 0)
	{
	  LARCH_opts.ase_abi = ilp32[suf[5]];
	  LARCH_opts.ase_ilp32 = 1;
	}
      else
	ret = 0;
      break;

    case OPTION_FLOAT_ISA:
      if (strcasecmp (arg, "soft") == 0)
	LARCH_opts.ase_nf = 1;
      else if (strcasecmp (arg, "single") == 0)
	LARCH_opts.ase_sf = 1;
      else if (strcasecmp (arg, "double") == 0)
	{
	  LARCH_opts.ase_sf = 1;
	  LARCH_opts.ase_df = 1;
	}
      else
	ret = 0;
      break;

    case OPTION_LA_LOCAL_WITH_ABS:
      LARCH_opts.ase_labs = 1;
      break;

    case OPTION_LA_GLOBAL_WITH_PCREL:
      LARCH_opts.ase_gpcr = 1;
      break;

    case OPTION_LA_GLOBAL_WITH_ABS:
      LARCH_opts.ase_gabs = 1;
      break;

    case OPTION_IGNORE:
      break;

    default:
      ret = 0;
      break;
    }
  return ret;
}

static struct htab *r_htab = NULL;
static struct htab *f_htab = NULL;
static struct htab *c_htab = NULL;
static struct htab *cr_htab = NULL;
static struct htab *v_htab = NULL;
static struct htab *x_htab = NULL;

void
loongarch_after_parse_args ()
{
  /* Set default ABI/ISA LP64D.  */
  if (!LARCH_opts.ase_ilp32)
    {
      if (strcmp (default_arch, "loongarch64") == 0)
	{
	  LARCH_opts.ase_abi = EF_LOONGARCH_ABI_DOUBLE_FLOAT;
	  LARCH_opts.ase_ilp32 = 1;
	  LARCH_opts.ase_lp64 = 1;
	}
      else if (strcmp (default_arch, "loongarch32") == 0)
	{
	  LARCH_opts.ase_abi = EF_LOONGARCH_ABI_DOUBLE_FLOAT;
	  LARCH_opts.ase_ilp32 = 1;
	}
      else
	as_bad ("unknown default architecture `%s'", default_arch);
    }

  LARCH_opts.ase_abi |= EF_LOONGARCH_OBJABI_V1;
  /* Set default ISA double-float.  */
  if (!LARCH_opts.ase_nf
      && !LARCH_opts.ase_sf
      && !LARCH_opts.ase_df)
    {
      LARCH_opts.ase_sf = 1;
      LARCH_opts.ase_df = 1;
    }

  size_t i;

  assert(LARCH_opts.ase_ilp32);

  /* Init ilp32/lp64 registers names.  */
  if (!r_htab)
    r_htab = str_htab_create (), str_hash_insert (r_htab, "", 0, 0);

  for (i = 0; i < ARRAY_SIZE (loongarch_r_normal_name); i++)
    str_hash_insert (r_htab, loongarch_r_normal_name[i], (void *) (i + 1), 0);

  if (!cr_htab)
    cr_htab = str_htab_create (), str_hash_insert (cr_htab, "", 0, 0);

  for (i = 0; i < ARRAY_SIZE (loongarch_cr_normal_name); i++)
    str_hash_insert (cr_htab, loongarch_cr_normal_name[i], (void *) (i + 1), 0);

  /* Init single/double float registers names.  */
  if (LARCH_opts.ase_sf || LARCH_opts.ase_df)
    {
      if (!f_htab)
	f_htab = str_htab_create (), str_hash_insert (f_htab, "", 0, 0);

      for (i = 0; i < ARRAY_SIZE (loongarch_f_normal_name); i++)
	str_hash_insert (f_htab, loongarch_f_normal_name[i], (void *) (i + 1),
			 0);

      if (!c_htab)
	c_htab = str_htab_create (), str_hash_insert (c_htab, "", 0, 0);

      for (i = 0; i < ARRAY_SIZE (loongarch_c_normal_name); i++)
	str_hash_insert (c_htab, loongarch_c_normal_name[i], (void *) (i + 1),
			 0);

    }

  /* Init lsx registers names.  */
  if (LARCH_opts.ase_lsx)
    {
      if (!v_htab)
	v_htab = str_htab_create (), str_hash_insert (v_htab, "", 0, 0);
      for (i = 0; i < ARRAY_SIZE (loongarch_v_normal_name); i++)
	str_hash_insert (v_htab, loongarch_v_normal_name[i], (void *) (i + 1),
			 0);
    }

  /* Init lasx registers names.  */
  if (LARCH_opts.ase_lasx)
    {
      if (!x_htab)
	x_htab = str_htab_create (), str_hash_insert (x_htab, "", 0, 0);
      for (i = 0; i < ARRAY_SIZE (loongarch_x_normal_name); i++)
	str_hash_insert (x_htab, loongarch_x_normal_name[i], (void *) (i + 1),
			 0);
    }

  /* Init lp64 registers alias.  */
  if (LARCH_opts.ase_lp64)
    {
      for (i = 0; i < ARRAY_SIZE (loongarch_r_lp64_name); i++)
	str_hash_insert (r_htab, loongarch_r_lp64_name[i], (void *) (i + 1),
			 0);
      for (i = 0; i < ARRAY_SIZE (loongarch_r_lp64_name1); i++)
	str_hash_insert (r_htab, loongarch_r_lp64_name1[i], (void *) (i + 1),
			 0);
    }

  /* Init float-lp64 registers alias */
  if ((LARCH_opts.ase_sf || LARCH_opts.ase_df) && LARCH_opts.ase_lp64)
    {
      for (i = 0; i < ARRAY_SIZE (loongarch_f_lp64_name); i++)
	str_hash_insert (f_htab, loongarch_f_lp64_name[i],
			 (void *) (i + 1), 0);
      for (i = 0; i < ARRAY_SIZE (loongarch_f_lp64_name1); i++)
	str_hash_insert (f_htab, loongarch_f_lp64_name1[i],
			 (void *) (i + 1), 0);
    }
}

const char *
loongarch_target_format ()
{
  return LARCH_opts.ase_lp64 ? "elf64-loongarch" : "elf32-loongarch";
}

void
md_begin ()
{
  const struct loongarch_opcode *it;
  struct loongarch_ase *ase;
  for (ase = loongarch_ASEs; ase->enabled; ase++)
    for (it = ase->opcodes; it->name; it++)
      {
	if (loongarch_check_format (it->format) != 0)
	  as_fatal (_("insn name: %s\tformat: %s\tsyntax error"),
		    it->name, it->format);
	if (it->mask == 0 && it->macro == 0)
	  as_fatal (_("insn name: %s\nformat: %s\nwe want macro but "
		      "macro is NULL"),
		    it->name, it->format);
	if (it->macro
	    && loongarch_check_macro (it->format, it->macro) != 0)
	  as_fatal (_("insn name: %s\nformat: %s\nmacro: %s\tsyntax error"),
		    it->name, it->format, it->macro);
      }

  /* FIXME: expressionS use 'offsetT' as constant,
   * we want this is 64-bit type.  */
  assert (8 <= sizeof (offsetT));
}

unsigned long
loongarch_mach (void)
{
  return LARCH_opts.ase_lp64 ? bfd_mach_loongarch64 : bfd_mach_loongarch32;
}

static const expressionS const_0 = { .X_op = O_constant, .X_add_number = 0 };

static void
s_loongarch_align (int arg)
{
  const char *t = input_line_pointer;
  while (!is_end_of_line[(unsigned char) *t] && *t != ',')
    ++t;
  if (*t == ',')
    s_align_ptwo (arg);
  else
    s_align_ptwo (0);
}

/* Handle the .dtprelword and .dtpreldword pseudo-ops.  They generate
   a 32-bit or 64-bit DTP-relative relocation (BYTES says which) for
   use in DWARF debug information.  */

static void
s_dtprel (int bytes)
{
  expressionS ex;
  char *p;

  expression (&ex);

  if (ex.X_op != O_symbol)
    {
      as_bad (_("Unsupported use of %s"),
	      (bytes == 8 ? ".dtpreldword" : ".dtprelword"));
      ignore_rest_of_line ();
    }

  p = frag_more (bytes);
  md_number_to_chars (p, 0, bytes);
  fix_new_exp (frag_now, p - frag_now->fr_literal, bytes, &ex, FALSE,
	       (bytes == 8
		? BFD_RELOC_LARCH_TLS_DTPREL64
		: BFD_RELOC_LARCH_TLS_DTPREL32));

  demand_empty_rest_of_line ();
}

static const pseudo_typeS loongarch_pseudo_table[] =
{
  { "align", s_loongarch_align, -4 },
  { "dword", cons, 8 },
  { "word", cons, 4 },
  { "half", cons, 2 },
  { "dtprelword", s_dtprel, 4 },
  { "dtpreldword", s_dtprel, 8 },
  { NULL, NULL, 0 },
};

void
loongarch_pop_insert (void)
{
  pop_insert (loongarch_pseudo_table);
}

#define INTERNAL_LABEL_SPECIAL 10
static unsigned long internal_label_count[INTERNAL_LABEL_SPECIAL] = { 0 };

static const char *
loongarch_internal_label_name (unsigned long label, int augend)
{
  static char symbol_name_build[24];
  unsigned long want_label;
  char *p;

  want_label = internal_label_count[label] + augend;

  p = symbol_name_build;
#ifdef LOCAL_LABEL_PREFIX
  *p++ = LOCAL_LABEL_PREFIX;
#endif
  *p++ = 'L';
  for (; label; label /= 10)
    *p++ = label % 10 + '0';
  /* Make sure internal label never belong to normal label namespace.  */
  *p++ = ':';
  for (; want_label; want_label /= 10)
    *p++ = want_label % 10 + '0';
  *p++ = '\0';
  return symbol_name_build;
}

static void
setup_internal_label_here (unsigned long label)
{
  assert (label < INTERNAL_LABEL_SPECIAL);
  internal_label_count[label]++;
  colon (loongarch_internal_label_name (label, 0));
}

void
get_internal_label (expressionS *label_expr, unsigned long label,
		    int augend /* 0 for previous, 1 for next.  */)
{
  assert (label < INTERNAL_LABEL_SPECIAL);
  if (augend == 0 && internal_label_count[label] == 0)
    as_fatal (_("internal error: we have no internal label yet"));
  label_expr->X_op = O_symbol;
  label_expr->X_add_symbol =
    symbol_find_or_make (loongarch_internal_label_name (label, augend));
  label_expr->X_add_number = 0;
}

static int
is_internal_label (const char *c_str)
{
  do
    {
      if (*c_str != ':')
	break;
      c_str++;
      if (!('0' <= *c_str && *c_str <= '9'))
	break;
      while ('0' <= *c_str && *c_str <= '9')
	c_str++;
      if (*c_str != 'b' && *c_str != 'f')
	break;
      c_str++;
      return *c_str == '\0';
    }
  while (0);
  return 0;
}

static int
is_label (const char *c_str)
{
  if (is_internal_label (c_str))
    return 1;
  else if ('0' <= *c_str && *c_str <= '9')
    {
      /* [0-9]+[bf]  */
      while ('0' <= *c_str && *c_str <= '9')
	c_str++;
      return *c_str == 'b' || *c_str == 'f';
    }
  else if (is_name_beginner (*c_str))
    {
      /* [a-zA-Z\._\$][0-9a-zA-Z\._\$]*  */
      c_str++;
      while (is_part_of_name (*c_str))
	c_str++;
      return *c_str == '\0';
    }
  else
    return 0;
}

static int
is_label_with_addend (const char *c_str)
{
  if (is_internal_label (c_str))
    return 1;
  else if ('0' <= *c_str && *c_str <= '9')
    {
      /* [0-9]+[bf]  */
      while ('0' <= *c_str && *c_str <= '9')
	c_str++;
      if (*c_str == 'b' || *c_str == 'f')
	c_str++;
      else
	return 0;
      return *c_str == '\0'
		       || ((*c_str == '-' || *c_str == '+')
			   && is_unsigned (c_str + 1));
    }
  else if (is_name_beginner (*c_str))
    {
      /* [a-zA-Z\._\$][0-9a-zA-Z\._\$]*  */
      c_str++;
      while (is_part_of_name (*c_str))
	c_str++;
      return *c_str == '\0'
		       || ((*c_str == '-' || *c_str == '+')
			   && is_unsigned (c_str + 1));
    }
  else
    return 0;
}

static int32_t
loongarch_args_parser_can_match_arg_helper (char esc_ch1, char esc_ch2,
					    const char *bit_field,
					    const char *arg, void *context)
{
  struct loongarch_cl_insn *ip = context;
  offsetT imm, ret = 0;
  size_t reloc_num_we_have = MAX_RELOC_NUMBER_A_INSN - ip->reloc_num;
  size_t reloc_num = 0;

  if (!ip->match_now)
    return 0;

  switch (esc_ch1)
    {
    case 'l':
      switch (esc_ch2)
	{
	default:
	  ip->match_now = is_label (arg);
	  if (!ip->match_now && is_label_with_addend (arg))
	    as_fatal (_("This label shouldn't be with addend."));
	  break;
	case 'a':
	  ip->match_now = is_label_with_addend (arg);
	  break;
	}
      break;
    case 's':
    case 'u':
      ip->match_now =
	loongarch_parse_expr (arg, ip->reloc_info + ip->reloc_num,
			      reloc_num_we_have, &reloc_num, &imm) == 0;

      if (!ip->match_now)
	break;

      ret = imm;
      if (reloc_num)
	{
	  bfd_reloc_code_real_type reloc_type = BFD_RELOC_NONE;
	  reloc_num_we_have -= reloc_num;
	  if (reloc_num_we_have == 0)
	    as_fatal (_("expr too huge") /* Want one more reloc.  */);
	  if (esc_ch1 == 'u')
	    {
	      if (strncmp (bit_field, "10:12", strlen ("10:12")) == 0)
		reloc_type = BFD_RELOC_LARCH_SOP_POP_32_U_10_12;
	    }
	  else if (esc_ch1 == 's')
	    {
	      if (strncmp (bit_field, "10:16<<2", strlen ("10:16<<2")) == 0)
		reloc_type = BFD_RELOC_LARCH_SOP_POP_32_S_10_16_S2;
	      else if (strncmp (bit_field, "0:5|10:16<<2",
				strlen ("0:5|10:16<<2")) == 0)
		reloc_type = BFD_RELOC_LARCH_SOP_POP_32_S_0_5_10_16_S2;
	      else if (strncmp (bit_field, "0:10|10:16<<2",
				strlen ("0:10|10:16<<2")) == 0)
		reloc_type = BFD_RELOC_LARCH_SOP_POP_32_S_0_10_10_16_S2;
	      else if (strncmp (bit_field, "10:12", strlen ("10:12")) == 0)
		reloc_type = BFD_RELOC_LARCH_SOP_POP_32_S_10_12;
	      else if (strncmp (bit_field, "5:20", strlen ("5:20")) == 0)
		reloc_type = BFD_RELOC_LARCH_SOP_POP_32_S_5_20;
	      else if (strncmp (bit_field, "10:16", strlen ("10:16")) == 0)
		reloc_type = BFD_RELOC_LARCH_SOP_POP_32_S_10_16;
	      else if (strncmp (bit_field, "10:5", strlen ("10:5")) == 0)
		reloc_type = BFD_RELOC_LARCH_SOP_POP_32_S_10_5;
	    }
	  if (reloc_type == BFD_RELOC_NONE)
	    as_fatal (
		      _("not support reloc bit-field\nfmt: %c%c %s\nargs: %s"),
		      esc_ch1, esc_ch2, bit_field, arg);
	  if (ip->reloc_info[0].type >= BFD_RELOC_LARCH_B16
	      && ip->reloc_info[0].type < BFD_RELOC_LARCH_RELAX)
	    {
	      /* As we compact stack-relocs, it is no need for pop operation.
		 But break out until here in order to check the imm field.
		 May be reloc_num > 1 if implement relax?  */
	      ip->reloc_num += reloc_num;
	      break;
	    }
	  reloc_num++;
	  ip->reloc_num += reloc_num;
	  ip->reloc_info[ip->reloc_num - 1].type = reloc_type;
	  ip->reloc_info[ip->reloc_num - 1].value = const_0;
	}
      break;
    case 'r':
      imm = (intptr_t) str_hash_find (r_htab, arg);
      ip->match_now = 0 < imm;
      ret = imm - 1;
      break;
    case 'f':
      imm = (intptr_t) str_hash_find (f_htab, arg);
      ip->match_now = 0 < imm;
      ret = imm - 1;
      break;
    case 'c':
      switch (esc_ch2)
	{
	case 'r':
	  imm = (intptr_t) str_hash_find (cr_htab, arg);
	  break;
	default:
	  imm = (intptr_t) str_hash_find (c_htab, arg);
	}
      ip->match_now = 0 < imm;
      ret = imm - 1;
      break;
    case 'v':
      imm = (intptr_t) str_hash_find (v_htab, arg);
      ip->match_now = 0 < imm;
      ret = imm - 1;
      break;
    case 'x':
      imm = (intptr_t) str_hash_find (x_htab, arg);
      ip->match_now = 0 < imm;
      ret = imm - 1;
      break;
    case '\0':
      ip->all_match = ip->match_now;
      ip->insn_length =
	ip->insn->mask ? loongarch_insn_length (ip->insn->match) : 0;
      /* FIXME: now we have no relax insn.  */
      ip->relax_max_length = ip->insn_length;
      break;
    default:
      as_fatal (_("unknown escape"));
    }

  do
    {
      /* Check imm overflow.  */
      int bit_width, bits_needed_s, bits_needed_u;
      char *t;

      if (!ip->match_now)
	break;

      if (0 < reloc_num)
	break;

      bit_width = loongarch_get_bit_field_width (bit_field, &t);

      if (bit_width == -1)
	/* No specify bit width.  */
	break;

      imm = ret;
      if (t[0] == '<' && t[1] == '<')
	{
	  int i = strtol (t += 2, &t, 10), j;
	  for (j = i; 0 < j; j--, imm >>= 1)
	    if (imm & 1)
	      as_fatal (_("require imm low %d bit is 0."), i);
	}

      if (*t == '+')
	imm -= strtol (t, &t, 10);

      bits_needed_s = loongarch_bits_imm_needed (imm, 1);
      bits_needed_u = loongarch_bits_imm_needed (imm, 0);

      if ((esc_ch1 == 's' && bit_width < bits_needed_s)
	  || (esc_ch1 != 's' && bit_width < bits_needed_u))
	/* How to do after we detect overflow.  */
	as_fatal (_("Immediate overflow.\n"
		    "format: %c%c%s\n"
		    "arg: %s"),
		  esc_ch1, esc_ch2, bit_field, arg);
    }
  while (0);

  if (esc_ch1 != '\0')
    {
      ip->args[ip->arg_num] = ret;
      ip->arg_num++;
    }
  return ret;
}

static void
get_loongarch_opcode (struct loongarch_cl_insn *insn)
{
  const struct loongarch_opcode *it;
  struct loongarch_ase *ase;
  for (ase = loongarch_ASEs; ase->enabled; ase++)
    {
      if (!*ase->enabled || (ase->include && !*ase->include)
	  || (ase->exclude && *ase->exclude))
	continue;

      if (!ase->name_hash_entry)
	{
	  ase->name_hash_entry = str_htab_create ();
	  for (it = ase->opcodes; it->name; it++)
	    {
	      if ((!it->include || (it->include && *it->include))
		  && (!it->exclude || (it->exclude && !(*it->exclude))))
		str_hash_insert (ase->name_hash_entry, it->name,
				 (void *) it, 0);
	    }
	}

      if ((it = str_hash_find (ase->name_hash_entry, insn->name)) == NULL)
	continue;

      do
	{
	  insn->insn = it;
	  insn->match_now = 1;
	  insn->all_match = 0;
	  insn->arg_num = 0;
	  insn->reloc_num = 0;
	  insn->insn_bin = (loongarch_foreach_args
			    (it->format, insn->arg_strs,
			     loongarch_args_parser_can_match_arg_helper,
			     insn));
	  if (insn->all_match && !(it->include && !*it->include)
	      && !(it->exclude && *it->exclude))
	    {
	      insn->insn_bin |= it->match;
	      return;
	    }
	  it++;
	}
      while (it->name && strcasecmp (it->name, insn->name) == 0);
    }
}

static int
check_this_insn_before_appending (struct loongarch_cl_insn *ip)
{
  int ret = 0;

  if (strncmp (ip->name, "la.abs", 6) == 0)
    {
      ip->reloc_info[ip->reloc_num].type = BFD_RELOC_LARCH_MARK_LA;
      ip->reloc_info[ip->reloc_num].value = const_0;
      ip->reloc_num++;
    }
  else if (ip->insn->mask == 0xffff8000
	   /* amswap.w  rd, rk, rj  */
	   && ((ip->insn_bin & 0xfff00000) == 0x38600000
	       /* ammax_db.wu  rd, rk, rj  */
	       || (ip->insn_bin & 0xffff0000) == 0x38700000
	       /* ammin_db.wu  rd, rk, rj  */
	       || (ip->insn_bin & 0xffff0000) == 0x38710000))
    {
      /* For AMO insn amswap.[wd], amadd.[wd], etc.  */
      if (ip->args[0] != 0
	  && (ip->args[0] == ip->args[1] || ip->args[0] == ip->args[2]))
	as_fatal (_("AMO insns require rd != base && rd != rt"
		    " when rd isn't $r0"));
    }
  else if ((ip->insn->mask == 0xffe08000
	    /* bstrins.w  rd, rj, msbw, lsbw  */
	    && (ip->insn_bin & 0xffe00000) == 0x00600000)
	   || (ip->insn->mask == 0xffc00000
	       /* bstrins.d  rd, rj, msbd, lsbd  */
	       && (ip->insn_bin & 0xff800000) == 0x00800000))
    {
      /* For bstr(ins|pick).[wd].  */
      if (ip->args[2] < ip->args[3])
	as_fatal (_("bstr(ins|pick).[wd] require msbd >= lsbd"));
    }
  else if (ip->insn->mask != 0 && (ip->insn_bin & 0xfe0003c0) == 0x04000000
	   /* csrxchg  rd, rj, csr_num  */
	   && (strcmp ("csrxchg", ip->name) == 0))
    as_fatal (_("csrxchg require rj != $r0 && rj != $r1"));

  return ret;
}

static void
install_insn (const struct loongarch_cl_insn *insn)
{
  char *f = insn->frag->fr_literal + insn->where;
  if (0 < insn->insn_length)
    md_number_to_chars (f, insn->insn_bin, insn->insn_length);
}

static void
move_insn (struct loongarch_cl_insn *insn, fragS *frag, long where)
{
  size_t i;
  insn->frag = frag;
  insn->where = where;
  for (i = 0; i < insn->reloc_num; i++)
    {
      insn->fixp[i]->fx_frag = frag;
      insn->fixp[i]->fx_where = where;
    }
  install_insn (insn);
}

/* Add INSN to the end of the output.  */
static void
append_fixed_insn (struct loongarch_cl_insn *insn)
{
  char *f = frag_more (insn->insn_length);
  move_insn (insn, frag_now, f - frag_now->fr_literal);
}

static void
append_fixp_and_insn (struct loongarch_cl_insn *ip)
{
  reloc_howto_type *howto;
  bfd_reloc_code_real_type reloc_type;
  struct reloc_info *reloc_info = ip->reloc_info;
  size_t i;

  dwarf2_emit_insn (0);

  for (i = 0; i < ip->reloc_num; i++)
    {
      reloc_type = reloc_info[i].type;
      howto = bfd_reloc_type_lookup (stdoutput, reloc_type);
      if (howto == NULL)
	as_fatal (_("no HOWTO loong relocation number %d"), reloc_type);

      ip->fixp[i] =
	fix_new_exp (ip->frag, ip->where, bfd_get_reloc_size (howto),
		     &reloc_info[i].value, FALSE, reloc_type);
    }

  if (ip->insn_length < ip->relax_max_length)
    as_fatal (_("Internal error: not support relax now"));
  else
    append_fixed_insn (ip);
}

/* Ask helper for returning a malloced c_str or NULL.  */
static char *
assember_macro_helper (const char *const args[], void *context_ptr)
{
  struct loongarch_cl_insn *insn = context_ptr;
  char *ret = NULL;
  if ( strcmp (insn->name, "li.w") == 0 || strcmp (insn->name, "li.d") == 0)
    {
      char args_buf[50], insns_buf[200];
      const char *arg_strs[6];
      uint32_t hi32, lo32;

      /* We pay attention to sign extend beacause it is chance of reduce insn.
	 The exception is 12-bit and hi-12-bit unsigned,
	 we need a 'ori' or a 'lu52i.d' accordingly.  */
      char all0_bit_vec, sign_bit_vec, allf_bit_vec, paritial_is_sext_of_prev;

      lo32 = insn->args[1] & 0xffffffff;
      hi32 = insn->args[1] >> 32;

      if (strcmp (insn->name, "li.w") == 0)
	{
	  if (hi32 != 0 && hi32 != 0xffffffff)
	    as_fatal (_("li overflow: hi32:0x%x lo32:0x%x"), hi32, lo32);
	  hi32 = lo32 & 0x80000000 ? 0xffffffff : 0;
	}

      if (strcmp (insn->name, "li.d") == 0 && !LARCH_opts.ase_lp64)
	as_fatal (_("we can't li.d on 32bit-arch"));

      snprintf (args_buf, sizeof (args_buf), "0x%x,0x%x,0x%x,0x%x,%s",
		(hi32 >> 20) & 0xfff, hi32 & 0xfffff, (lo32 >> 12) & 0xfffff,
		lo32 & 0xfff, args[0]);
      loongarch_split_args_by_comma (args_buf, arg_strs);

      all0_bit_vec =
	((((hi32 & 0xfff00000) == 0) << 3) | (((hi32 & 0x000fffff) == 0) << 2)
	 | (((lo32 & 0xfffff000) == 0) << 1) | ((lo32 & 0x00000fff) == 0));
      sign_bit_vec =
	((((hi32 & 0x80000000) != 0) << 3) | (((hi32 & 0x00080000) != 0) << 2)
	 | (((lo32 & 0x80000000) != 0) << 1) | ((lo32 & 0x00000800) != 0));
      allf_bit_vec =
	((((hi32 & 0xfff00000) == 0xfff00000) << 3)
	 | (((hi32 & 0x000fffff) == 0x000fffff) << 2)
	 | (((lo32 & 0xfffff000) == 0xfffff000) << 1)
	 | ((lo32 & 0x00000fff) == 0x00000fff));
      paritial_is_sext_of_prev =
	(all0_bit_vec ^ allf_bit_vec) & (all0_bit_vec ^ (sign_bit_vec << 1));

      static const char *const li_32bit[] =
	{
	  "lu12i.w %5,%3&0x80000?%3-0x100000:%3;ori %5,%5,%4;",
	  "lu12i.w %5,%3&0x80000?%3-0x100000:%3;",
	  "addi.w %5,$r0,%4&0x800?%4-0x1000:%4;",
	  "or %5,$r0,$r0;",
	};
      static const char *const li_hi_32bit[] =
	{
	  "lu32i.d %5,%2&0x80000?%2-0x100000:%2;"
	  "lu52i.d %5,%5,%1&0x800?%1-0x1000:%1;",
	  "lu52i.d %5,%5,%1&0x800?%1-0x1000:%1;",
	  "lu32i.d %5,%2&0x80000?%2-0x100000:%2;",
	  "",
	};
      do
	{
	  insns_buf[0] = '\0';
	  if (paritial_is_sext_of_prev == 0x7)
	    {
	      strcat (insns_buf, "lu52i.d %5,$r0,%1&0x800?%1-0x1000:%1;");
	      break;
	    }
	  if ((all0_bit_vec & 0x3) == 0x2)
	    strcat (insns_buf, "ori %5,$r0,%4;");
	  else
	    strcat (insns_buf, li_32bit[paritial_is_sext_of_prev & 0x3]);
	  strcat (insns_buf, li_hi_32bit[paritial_is_sext_of_prev >> 2]);
	}
      while (0);

      ret = loongarch_expand_macro (insns_buf, arg_strs, NULL, NULL,
				    sizeof (args_buf));
    }

  return ret;
}

/* Accept instructions separated by ';'
 * assuming 'not starting with space and not ending with space' or pass in
 * empty c_str.  */
static void
loongarch_assemble_INSNs (char *str)
{
  char *rest;
  size_t len_str = strlen(str);

  for (rest = str; *rest != ';' && *rest != '\0'; rest++);
  if (*rest == ';')
    *rest++ = '\0';

  if (*str == ':')
    {
      str++;
      setup_internal_label_here (strtol (str, &str, 10));
      str++;
    }

  do
    {
      if (*str == '\0')
	break;

      struct loongarch_cl_insn the_one = { 0 };
      the_one.name = str;

      for (; *str && *str != ' '; str++)
	;
      if (*str == ' ')
	*str++ = '\0';

      loongarch_split_args_by_comma (str, the_one.arg_strs);
      get_loongarch_opcode (&the_one);

      if (!the_one.all_match)
	{
	  char *ss = loongarch_cat_splited_strs (the_one.arg_strs);
	  as_bad (_("no match insn: %s\t%s"), the_one.name, ss ? ss : "");
	  free(ss);
	  return;
	}

      if (check_this_insn_before_appending (&the_one) != 0)
	break;

      append_fixp_and_insn (&the_one);
      if (the_one.insn_length == 0 && the_one.insn->macro)
	{
	  char *c_str = loongarch_expand_macro (the_one.insn->macro,
						the_one.arg_strs,
						assember_macro_helper,
						&the_one, len_str);
	  loongarch_assemble_INSNs (c_str);
	  free (c_str);
	}
    }
  while (0);

  if (*rest != '\0')
    loongarch_assemble_INSNs (rest);
}

void
md_assemble (char *str)
{
  loongarch_assemble_INSNs (str);
}

const char *
md_atof (int type, char *litP, int *sizeP)
{
  return ieee_md_atof (type, litP, sizeP, FALSE);
}

void
md_number_to_chars (char *buf, valueT val, int n)
{
  number_to_chars_littleendian (buf, val, n);
}

/* The location from which a PC relative jump should be calculated,
   given a PC relative reloc.  */
long
md_pcrel_from (fixS *fixP ATTRIBUTE_UNUSED)
{
  return 0;
}

static void fix_reloc_insn (fixS *fixP, bfd_vma reloc_val, char *buf)
{
  reloc_howto_type *howto;
  insn_t insn;
  howto = bfd_reloc_type_lookup (stdoutput, fixP->fx_r_type);

  insn = bfd_getl32 (buf);

  if (!loongarch_adjust_reloc_bitsfield(howto, &reloc_val))
    as_warn_where (fixP->fx_file, fixP->fx_line, "Reloc overflow");

  insn = (insn & (insn_t)howto->src_mask)
    | ((insn & (~(insn_t)howto->dst_mask)) | reloc_val);

  bfd_putl32 (insn, buf);
}

void
md_apply_fix (fixS *fixP, valueT *valP, segT seg ATTRIBUTE_UNUSED)
{
  static int64_t stack_top;
  static int last_reloc_is_sop_push_pcrel_1 = 0;
  int last_reloc_is_sop_push_pcrel = last_reloc_is_sop_push_pcrel_1;
  segT sub_segment;
  last_reloc_is_sop_push_pcrel_1 = 0;

  char *buf = fixP->fx_frag->fr_literal + fixP->fx_where;
  switch (fixP->fx_r_type)
    {
    case BFD_RELOC_LARCH_SOP_PUSH_TLS_TPREL:
    case BFD_RELOC_LARCH_SOP_PUSH_TLS_GD:
    case BFD_RELOC_LARCH_SOP_PUSH_TLS_GOT:
    case BFD_RELOC_LARCH_TLS_LE_HI20:
    case BFD_RELOC_LARCH_TLS_LE_LO12:
    case BFD_RELOC_LARCH_TLS_LE64_LO20:
    case BFD_RELOC_LARCH_TLS_LE64_HI12:
    case BFD_RELOC_LARCH_TLS_IE_PC_HI20:
    case BFD_RELOC_LARCH_TLS_IE_PC_LO12:
    case BFD_RELOC_LARCH_TLS_IE64_PC_LO20:
    case BFD_RELOC_LARCH_TLS_IE64_PC_HI12:
    case BFD_RELOC_LARCH_TLS_IE_HI20:
    case BFD_RELOC_LARCH_TLS_IE_LO12:
    case BFD_RELOC_LARCH_TLS_IE64_LO20:
    case BFD_RELOC_LARCH_TLS_IE64_HI12:
    case BFD_RELOC_LARCH_TLS_LD_PC_HI20:
    case BFD_RELOC_LARCH_TLS_LD_HI20:
    case BFD_RELOC_LARCH_TLS_GD_PC_HI20:
    case BFD_RELOC_LARCH_TLS_GD_HI20:
      /* Add tls lo (got_lo reloc type).  */
      if (fixP->fx_addsy == NULL)
	as_bad_where (fixP->fx_file, fixP->fx_line,
		      _("Relocation against a constant"));
      S_SET_THREAD_LOCAL (fixP->fx_addsy);
      break;

    case BFD_RELOC_LARCH_SOP_PUSH_PCREL:
      if (fixP->fx_addsy == NULL)
	as_bad_where (fixP->fx_file, fixP->fx_line,
		      _("Relocation against a constant"));

      last_reloc_is_sop_push_pcrel_1 = 1;
      if (S_GET_SEGMENT (fixP->fx_addsy) == seg)
	stack_top = (S_GET_VALUE (fixP->fx_addsy) + fixP->fx_offset
		     - (fixP->fx_where + fixP->fx_frag->fr_address));
      else
	stack_top = 0;
      break;

    case BFD_RELOC_LARCH_SOP_POP_32_S_10_5:
    case BFD_RELOC_LARCH_SOP_POP_32_S_10_12:
    case BFD_RELOC_LARCH_SOP_POP_32_U_10_12:
    case BFD_RELOC_LARCH_SOP_POP_32_S_10_16:
    case BFD_RELOC_LARCH_SOP_POP_32_S_10_16_S2:
    case BFD_RELOC_LARCH_SOP_POP_32_S_5_20:
    case BFD_RELOC_LARCH_SOP_POP_32_U:
    case BFD_RELOC_LARCH_SOP_POP_32_S_0_5_10_16_S2:
    case BFD_RELOC_LARCH_SOP_POP_32_S_0_10_10_16_S2:
      if (!last_reloc_is_sop_push_pcrel)
	break;

      fix_reloc_insn (fixP, (bfd_vma)stack_top, buf);
      break;

    case BFD_RELOC_64:
    case BFD_RELOC_32:
      if (fixP->fx_r_type == BFD_RELOC_32
	  && fixP->fx_addsy && fixP->fx_subsy
	  && (sub_segment = S_GET_SEGMENT (fixP->fx_subsy))
	  && strcmp (sub_segment->name, ".eh_frame") == 0
	  && S_GET_VALUE (fixP->fx_subsy)
	  == fixP->fx_frag->fr_address + fixP->fx_where)
	{
	  fixP->fx_r_type = BFD_RELOC_LARCH_32_PCREL;
	  fixP->fx_subsy = NULL;
	  break;
	}

      if (fixP->fx_subsy)
	{
	  fixP->fx_next = xmemdup (fixP, sizeof (*fixP), sizeof (*fixP));
	  fixP->fx_next->fx_addsy = fixP->fx_subsy;
	  fixP->fx_next->fx_subsy = NULL;
	  fixP->fx_next->fx_offset = 0;
	  fixP->fx_subsy = NULL;

	  switch (fixP->fx_r_type)
	    {
	    case BFD_RELOC_64:
	      fixP->fx_r_type = BFD_RELOC_LARCH_ADD64;
	      fixP->fx_next->fx_r_type = BFD_RELOC_LARCH_SUB64;
	      break;
	    case BFD_RELOC_32:
	      fixP->fx_r_type = BFD_RELOC_LARCH_ADD32;
	      fixP->fx_next->fx_r_type = BFD_RELOC_LARCH_SUB32;
	      break;
	    default:
	      break;
	    }

	  md_number_to_chars (buf, 0, fixP->fx_size);
	}

      if (fixP->fx_addsy == NULL)
	{
	  fixP->fx_done = 1;
	  md_number_to_chars (buf, *valP, fixP->fx_size);
	}
      break;

    case BFD_RELOC_24:
    case BFD_RELOC_16:
    case BFD_RELOC_8:
      fixP->fx_next = xmemdup (fixP, sizeof (*fixP), sizeof (*fixP));
      fixP->fx_next->fx_addsy = fixP->fx_subsy;
      fixP->fx_next->fx_subsy = NULL;
      fixP->fx_next->fx_offset = 0;
      fixP->fx_subsy = NULL;

      switch (fixP->fx_r_type)
	{
	case BFD_RELOC_24:
	  fixP->fx_r_type = BFD_RELOC_LARCH_ADD24;
	  fixP->fx_next->fx_r_type = BFD_RELOC_LARCH_SUB24;
	  break;
	case BFD_RELOC_16:
	  fixP->fx_r_type = BFD_RELOC_LARCH_ADD16;
	  fixP->fx_next->fx_r_type = BFD_RELOC_LARCH_SUB16;
	  break;
	case BFD_RELOC_8:
	  fixP->fx_r_type = BFD_RELOC_LARCH_ADD8;
	  fixP->fx_next->fx_r_type = BFD_RELOC_LARCH_SUB8;
	  break;
	default:
	  break;
	}

      md_number_to_chars (buf, 0, fixP->fx_size);

      if (fixP->fx_next->fx_addsy == NULL)
	fixP->fx_next->fx_done = 1;

      if (fixP->fx_addsy == NULL)
	{
	  fixP->fx_done = 1;
	  md_number_to_chars (buf, *valP, fixP->fx_size);
	}
      break;

    case BFD_RELOC_LARCH_B16:
    case BFD_RELOC_LARCH_B21:
    case BFD_RELOC_LARCH_B26:
      if (fixP->fx_addsy == NULL)
	{
	  as_bad_where (fixP->fx_file, fixP->fx_line,
			_ ("Relocation against a constant."));
	}
      if (S_GET_SEGMENT (fixP->fx_addsy) == seg
	  && !S_FORCE_RELOC (fixP->fx_addsy, 1))
	{
	  int64_t sym_addend = S_GET_VALUE (fixP->fx_addsy) + fixP->fx_offset;
	  int64_t pc = fixP->fx_where + fixP->fx_frag->fr_address;
	  fix_reloc_insn (fixP, sym_addend - pc, buf);
	  fixP->fx_done = 1;
	}

      break;

    default:
      break;
    }
}

int
loongarch_relax_frag (asection *sec ATTRIBUTE_UNUSED,
		      fragS *fragp ATTRIBUTE_UNUSED,
		      long stretch ATTRIBUTE_UNUSED)
{
  return 0;
}

int
md_estimate_size_before_relax (fragS *fragp ATTRIBUTE_UNUSED,
			       asection *segtype ATTRIBUTE_UNUSED)
{
  return 0;
}

int
loongarch_fix_adjustable (fixS *fix)
{
  /* Prevent all adjustments to global symbols.  */
  if (S_IS_EXTERNAL (fix->fx_addsy)
      || S_IS_WEAK (fix->fx_addsy)
      || S_FORCE_RELOC (fix->fx_addsy, true))
    return 0;

  return 1;
}

/* Translate internal representation of relocation info to BFD target
   format.  */
arelent *
tc_gen_reloc (asection *section ATTRIBUTE_UNUSED, fixS *fixp)
{
  arelent *reloc = (arelent *) xmalloc (sizeof (arelent));

  reloc->sym_ptr_ptr = (asymbol **) xmalloc (sizeof (asymbol *));
  *reloc->sym_ptr_ptr = symbol_get_bfdsym (fixp->fx_addsy);
  reloc->address = fixp->fx_frag->fr_address + fixp->fx_where;
  reloc->addend = fixp->fx_offset;

  reloc->howto = bfd_reloc_type_lookup (stdoutput, fixp->fx_r_type);
  if (reloc->howto == NULL)
    {
      as_bad_where (fixp->fx_file, fixp->fx_line,
		    _("cannot represent %s relocation in object file"),
		    bfd_get_reloc_code_name (fixp->fx_r_type));
      return NULL;
    }

  return reloc;
}

/* Convert a machine dependent frag.  */
void
md_convert_frag (bfd *abfd ATTRIBUTE_UNUSED, segT asec ATTRIBUTE_UNUSED,
		 fragS *fragp ATTRIBUTE_UNUSED)
{
  /* fragp->fr_fix += 8; */
}

/* Standard calling conventions leave the CFA at SP on entry.  */
void
loongarch_cfi_frame_initial_instructions (void)
{
  cfi_add_CFA_def_cfa_register (3 /* $sp */);
}

void
tc_loongarch_parse_to_dw2regnum (expressionS *exp)
{
  expression_and_evaluate (exp);
}

void
md_show_usage (FILE *stream)
{
  fprintf (stream, _("LARCH options:\n"));
  /* FIXME */
}

/* Fill in an rs_align_code fragment.  We want to fill 'andi $r0,$r0,0'.  */
void
loongarch_handle_align (fragS *fragp)
{
  /* char nop_opcode; */
  char *p;
  int bytes, size, excess;
  valueT opcode;

  if (fragp->fr_type != rs_align_code)
    return;

  struct loongarch_cl_insn nop =
    { .name = "andi", .arg_strs = { "$r0", "$r0", "0", NULL } };

  get_loongarch_opcode (&nop);
  gas_assert (nop.all_match);

  p = fragp->fr_literal + fragp->fr_fix;
  opcode = nop.insn_bin;
  size = 4;

  bytes = fragp->fr_next->fr_address - fragp->fr_address - fragp->fr_fix;
  excess = bytes % size;

  gas_assert (excess < 4);
  fragp->fr_fix += excess;

  while (excess-- != 0)
    *p++ = 0;

  md_number_to_chars (p, opcode, size);
  fragp->fr_var = size;
}

void
loongarch_elf_final_processing (void)
{
  elf_elfheader (stdoutput)->e_flags = LARCH_opts.ase_abi;
}