opcodes/cgen-asm.c

/* CGEN generic assembler support code.
   Copyright (C) 1996-2020 Free Software Foundation, Inc.

   This file is part of libopcodes.

   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; if not, write to the Free Software Foundation, Inc.,
   51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA.  */

#include "sysdep.h"
#include <stdio.h>
#include "ansidecl.h"
#include "libiberty.h"
#include "safe-ctype.h"
#include "bfd.h"
#include "symcat.h"
#include "opcode/cgen.h"
#include "opintl.h"

static CGEN_INSN_LIST *  hash_insn_array      (CGEN_CPU_DESC, const CGEN_INSN *, int, int, CGEN_INSN_LIST **, CGEN_INSN_LIST *);
static CGEN_INSN_LIST *  hash_insn_list       (CGEN_CPU_DESC, const CGEN_INSN_LIST *, CGEN_INSN_LIST **, CGEN_INSN_LIST *);
static void              build_asm_hash_table (CGEN_CPU_DESC);

/* Set the cgen_parse_operand_fn callback.  */

void
cgen_set_parse_operand_fn (CGEN_CPU_DESC cd, cgen_parse_operand_fn fn)
{
  cd->parse_operand_fn = fn;
}

/* Called whenever starting to parse an insn.  */

void
cgen_init_parse_operand (CGEN_CPU_DESC cd)
{
  /* This tells the callback to re-initialize.  */
  (void) (* cd->parse_operand_fn)
    (cd, CGEN_PARSE_OPERAND_INIT, NULL, 0, 0, NULL, NULL);
}

/* Subroutine of build_asm_hash_table to add INSNS to the hash table.

   COUNT is the number of elements in INSNS.
   ENTSIZE is sizeof (CGEN_IBASE) for the target.
   ??? No longer used but leave in for now.
   HTABLE points to the hash table.
   HENTBUF is a pointer to sufficiently large buffer of hash entries.
   The result is a pointer to the next entry to use.

   The table is scanned backwards as additions are made to the front of the
   list and we want earlier ones to be prefered.  */

static CGEN_INSN_LIST *
hash_insn_array (CGEN_CPU_DESC cd,
		 const CGEN_INSN *insns,
		 int count,
		 int entsize ATTRIBUTE_UNUSED,
		 CGEN_INSN_LIST **htable,
		 CGEN_INSN_LIST *hentbuf)
{
  int i;

  for (i = count - 1; i >= 0; --i, ++hentbuf)
    {
      unsigned int hash;
      const CGEN_INSN *insn = &insns[i];

      if (! (* cd->asm_hash_p) (insn))
	continue;
      hash = (* cd->asm_hash) (CGEN_INSN_MNEMONIC (insn));
      hentbuf->next = htable[hash];
      hentbuf->insn = insn;
      htable[hash] = hentbuf;
    }

  return hentbuf;
}

/* Subroutine of build_asm_hash_table to add INSNS to the hash table.
   This function is identical to hash_insn_array except the insns are
   in a list.  */

static CGEN_INSN_LIST *
hash_insn_list (CGEN_CPU_DESC cd,
		const CGEN_INSN_LIST *insns,
		CGEN_INSN_LIST **htable,
		CGEN_INSN_LIST *hentbuf)
{
  const CGEN_INSN_LIST *ilist;

  for (ilist = insns; ilist != NULL; ilist = ilist->next, ++ hentbuf)
    {
      unsigned int hash;

      if (! (* cd->asm_hash_p) (ilist->insn))
	continue;
      hash = (* cd->asm_hash) (CGEN_INSN_MNEMONIC (ilist->insn));
      hentbuf->next = htable[hash];
      hentbuf->insn = ilist->insn;
      htable[hash] = hentbuf;
    }

  return hentbuf;
}

/* Build the assembler instruction hash table.  */

static void
build_asm_hash_table (CGEN_CPU_DESC cd)
{
  int count = cgen_insn_count (cd) + cgen_macro_insn_count (cd);
  CGEN_INSN_TABLE *insn_table = &cd->insn_table;
  CGEN_INSN_TABLE *macro_insn_table = &cd->macro_insn_table;
  unsigned int hash_size = cd->asm_hash_size;
  CGEN_INSN_LIST *hash_entry_buf;
  CGEN_INSN_LIST **asm_hash_table;
  CGEN_INSN_LIST *asm_hash_table_entries;

  /* The space allocated for the hash table consists of two parts:
     the hash table and the hash lists.  */

  asm_hash_table = (CGEN_INSN_LIST **)
    xmalloc (hash_size * sizeof (CGEN_INSN_LIST *));
  memset (asm_hash_table, 0, hash_size * sizeof (CGEN_INSN_LIST *));
  asm_hash_table_entries = hash_entry_buf = (CGEN_INSN_LIST *)
    xmalloc (count * sizeof (CGEN_INSN_LIST));

  /* Add compiled in insns.
     Don't include the first one as it is a reserved entry.  */
  /* ??? It was the end of all hash chains, and also the special
     "invalid insn" marker.  May be able to do it differently now.  */

  hash_entry_buf = hash_insn_array (cd,
				    insn_table->init_entries + 1,
				    insn_table->num_init_entries - 1,
				    insn_table->entry_size,
				    asm_hash_table, hash_entry_buf);

  /* Add compiled in macro-insns.  */

  hash_entry_buf = hash_insn_array (cd, macro_insn_table->init_entries,
				    macro_insn_table->num_init_entries,
				    macro_insn_table->entry_size,
				    asm_hash_table, hash_entry_buf);

  /* Add runtime added insns.
     Later added insns will be prefered over earlier ones.  */

  hash_entry_buf = hash_insn_list (cd, insn_table->new_entries,
				   asm_hash_table, hash_entry_buf);

  /* Add runtime added macro-insns.  */

  hash_insn_list (cd, macro_insn_table->new_entries,
		  asm_hash_table, hash_entry_buf);

  cd->asm_hash_table = asm_hash_table;
  cd->asm_hash_table_entries = asm_hash_table_entries;
}

/* Return the first entry in the hash list for INSN.  */

CGEN_INSN_LIST *
cgen_asm_lookup_insn (CGEN_CPU_DESC cd, const char *insn)
{
  unsigned int hash;

  if (cd->asm_hash_table == NULL)
    build_asm_hash_table (cd);

  hash = (* cd->asm_hash) (insn);
  return cd->asm_hash_table[hash];
}

/* Keyword parser.
   The result is NULL upon success or an error message.
   If successful, *STRP is updated to point passed the keyword.

   ??? At present we have a static notion of how to pick out a keyword.
   Later we can allow a target to customize this if necessary [say by
   recording something in the keyword table].  */

const char *
cgen_parse_keyword (CGEN_CPU_DESC cd ATTRIBUTE_UNUSED,
		    const char **strp,
		    CGEN_KEYWORD *keyword_table,
		    long *valuep)
{
  const CGEN_KEYWORD_ENTRY *ke;
  char buf[256];
  const char *p,*start;

  if (keyword_table->name_hash_table == NULL)
    (void) cgen_keyword_search_init (keyword_table, NULL);

  p = start = *strp;

  /* Allow any first character.  This is to make life easier for
     the fairly common case of suffixes, eg. 'ld.b.w', where the first
     character of the suffix ('.') is special.  */
  if (*p)
    ++p;

  /* Allow letters, digits, and any special characters.  */
  while (((p - start) < (int) sizeof (buf))
	 && *p
	 && (ISALNUM (*p)
	     || *p == '_'
	     || strchr (keyword_table->nonalpha_chars, *p)))
    ++p;

  if (p - start >= (int) sizeof (buf))
    {
      /* All non-empty CGEN keywords can fit into BUF.  The only thing
	 we can match here is the empty keyword.  */
      buf[0] = 0;
    }
  else
    {
      memcpy (buf, start, p - start);
      buf[p - start] = 0;
    }

  ke = cgen_keyword_lookup_name (keyword_table, buf);

  if (ke != NULL)
    {
      *valuep = ke->value;
      /* Don't advance pointer if we recognized the null keyword.  */
      if (ke->name[0] != 0)
	*strp = p;
      return NULL;
    }

  return "unrecognized keyword/register name";
}

/* Parse a small signed integer parser.
   ??? VALUEP is not a bfd_vma * on purpose, though this is confusing.
   Note that if the caller expects a bfd_vma result, it should call
   cgen_parse_address.  */

const char *
cgen_parse_signed_integer (CGEN_CPU_DESC cd,
			   const char **strp,
			   int opindex,
			   long *valuep)
{
  bfd_vma value;
  enum cgen_parse_operand_result result;
  const char *errmsg;

  errmsg = (* cd->parse_operand_fn)
    (cd, CGEN_PARSE_OPERAND_INTEGER, strp, opindex, BFD_RELOC_NONE,
     &result, &value);
  /* FIXME: Examine `result'.  */
  if (!errmsg)
    {
      /* Handle the case where a hex value is parsed on a 64-bit host.
	 A value like 0xffffe000 is clearly intended to be a negative
	 16-bit value, but on a 64-bit host it will be parsed by gas
	 as 0x00000000ffffe000.

	 The shifts below are designed not to produce compile time
	 warnings on a 32-bit host.  */
      if (sizeof (value) > 4
	  && result == CGEN_PARSE_OPERAND_RESULT_NUMBER
	  && value > 0
	  && (value & 0x80000000)
	  && ((value >> 31) == 1))
	value |= ((bfd_vma) -1) << 31;

      *valuep = value;
    }
  return errmsg;
}

/* Parse a small unsigned integer parser.
   ??? VALUEP is not a bfd_vma * on purpose, though this is confusing.
   Note that if the caller expects a bfd_vma result, it should call
   cgen_parse_address.  */

const char *
cgen_parse_unsigned_integer (CGEN_CPU_DESC cd,
			     const char **strp,
			     int opindex,
			     unsigned long *valuep)
{
  bfd_vma value;
  enum cgen_parse_operand_result result;
  const char *errmsg;

  errmsg = (* cd->parse_operand_fn)
    (cd, CGEN_PARSE_OPERAND_INTEGER, strp, opindex, BFD_RELOC_NONE,
     &result, &value);
  /* FIXME: Examine `result'.  */
  if (!errmsg)
    *valuep = value;
  return errmsg;
}

/* Address parser.  */

const char *
cgen_parse_address (CGEN_CPU_DESC cd,
		    const char **strp,
		    int opindex,
		    int opinfo,
		    enum cgen_parse_operand_result *resultp,
		    bfd_vma *valuep)
{
  bfd_vma value;
  enum cgen_parse_operand_result result_type;
  const char *errmsg;

  errmsg = (* cd->parse_operand_fn)
    (cd, CGEN_PARSE_OPERAND_ADDRESS, strp, opindex, opinfo,
     &result_type, &value);
  /* FIXME: Examine `result'.  */
  if (!errmsg)
    {
      if (resultp != NULL)
	*resultp = result_type;
      *valuep = value;
    }
  return errmsg;
}

/* Signed integer validation routine.  */

const char *
cgen_validate_signed_integer (long value, long min, long max)
{
  if (value < min || value > max)
    {
      static char buf[100];

      /* xgettext:c-format */
      sprintf (buf, _("operand out of range (%ld not between %ld and %ld)"),
		      value, min, max);
      return buf;
    }

  return NULL;
}

/* Unsigned integer validation routine.
   Supplying `min' here may seem unnecessary, but we also want to handle
   cases where min != 0 (and max > LONG_MAX).  */

const char *
cgen_validate_unsigned_integer (unsigned long value,
				unsigned long min,
				unsigned long max)
{
  if (value < min || value > max)
    {
      static char buf[100];

      /* xgettext:c-format */
      sprintf (buf, _("operand out of range (%lu not between %lu and %lu)"),
	       value, min, max);
      return buf;
    }

  return NULL;
}