* read-rtl.c (map_value, mapping, macro_group): New structures.

	(BELLWETHER_CODE): New macro.
	(modes, codes, bellwether_codes): New variables.
	(find_mode, uses_mode_macro_p, apply_mode_macro, find_code)
	(uses_code_macro_p, apply_code_macro, apply_macro_to_string)
	(apply_macro_to_rtx, uses_macro_p, add_condition_to_string)
	(add_condition_to_rtx, apply_macro_traverse, add_mapping)
	(add_map_value, initialize_macros): New functions.
	(def_hash, def_hash_eq_p): Generalize to anything that points to,
	or starts with, a char * field.
	(find_macro, read_mapping, check_code_macro): New functions.
	(read_rtx_1): New, split out from read_rtx.  Handle the new
	define_{mode,code}_{macro,attr} constructs.  Use find_macro
	to parse the name of a code or mode.  Use BELLWETHER_CODE to
	extract the format and to choose a suitable code for rtx_alloc.
	Modify recursive invocations to use read_rtx_1.
	(read_rtx): Call initialize_macros.  Apply code and mode macros
	to the rtx returned by read_rtx_1.  Cache everything after the
	first macro expansion for subsequent read_rtx calls.
	* doc/md.texi: Document new .md constructs.
	* config/mips/mips.md (GPR): New mode macro.
	(d, si8_di5): New mode attributes.
	(any_cond): New code macro.
	(add[sd]i3): Redefine using :GPR.
	(*add[sd]i3): Likewise, renaming from add[sd]i3_internal.
	(*add[sd]i3_sp[12], *add<mode>3_mips16): Redefine using :GPR, naming
	previously unnamed MIPS16 patterns.
	(*addsi3_extended): Renamed from addsi3_internal_2.  Fix overly long
	lines.  Don't match (plus (const_int 0) ...).
	(*addsi3_extended_mips16): Name previously unnamed MIPS16 pattern.
	Use a define_split to generate the addition.
	(sub[sd]i3): Redefine using :GPR.  Turn subsi3 into a define_insn.
	(subsi3_internal): Delete.
	(*subsi3_extended): Renamed from subsi3_internal_2.
	(bunordered, bordered, bunlt, bunge, buneq, bltgt, bunle, bungt)
	(beq, bne, bgt, bge, blt, ble, bgtu, bgeu, bltu, bleu): Redefine
	using an any_cond template.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@86404 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 643 insertions, 55 deletions

diff --git a/gcc/read-rtl.c b/gcc/read-rtl.c
index 2b9bd915d23..fe0c7a4044a 100644
--- a/gcc/read-rtl.c
+++ b/gcc/read-rtl.c
@@ -30,9 +30,76 @@ Software Foundation, 59 Temple Place - Suite 330, Boston, MA
 
 static htab_t md_constants;
 
+/* One element in a singly-linked list of (integer, string) pairs.  */
+struct map_value {
+  struct map_value *next;
+  int number;
+  const char *string;
+};
+
+/* Maps a macro or attribute name to a list of (integer, string) pairs.
+   The integers are mode or code values; the strings are either C conditions
+   or attribute values.  */
+struct mapping {
+  /* The name of the macro or attribute.  */
+  const char *name;
+
+  /* The group (modes or codes) to which the macro or attribute belongs.  */
+  struct macro_group *group;
+
+  /* Gives a unique number to the attribute or macro.  Numbers are
+     allocated consecutively, starting at 0.  */
+  int index;
+
+  /* The list of (integer, string) pairs.  */
+  struct map_value *values;
+};
+
+/* A structure for abstracting the common parts of code and mode macros.  */
+struct macro_group {
+  /* Tables of "mapping" structures, one for attributes and one for macros.  */
+  htab_t attrs, macros;
+
+  /* The number of "real" modes or codes (and by extension, the first
+     number available for use as a macro placeholder).  */
+  int num_builtins;
+
+  /* Treat the given string as the name of a standard mode or code and
+     return its integer value.  Use the given file for error reporting.  */
+  int (*find_builtin) (const char *, FILE *);
+
+  /* Return true if the given rtx uses the given mode or code.  */
+  bool (*uses_macro_p) (rtx, int);
+
+  /* Make the given rtx use the given mode or code.  */
+  void (*apply_macro) (rtx, int);
+};
+
+/* If CODE is the number of a code macro, return a real rtx code that
+   has the same format.  Return CODE otherwise.  */
+#define BELLWETHER_CODE(CODE) \
+  ((CODE) < NUM_RTX_CODE ? CODE : bellwether_codes[CODE - NUM_RTX_CODE])
+
 static void fatal_with_file_and_line (FILE *, const char *, ...)
   ATTRIBUTE_PRINTF_2 ATTRIBUTE_NORETURN;
 static void fatal_expected_char (FILE *, int, int) ATTRIBUTE_NORETURN;
+static int find_mode (const char *, FILE *);
+static bool uses_mode_macro_p (rtx, int);
+static void apply_mode_macro (rtx, int);
+static int find_code (const char *, FILE *);
+static bool uses_code_macro_p (rtx, int);
+static void apply_code_macro (rtx, int);
+static const char *apply_macro_to_string (const char *, struct mapping *, int);
+static rtx apply_macro_to_rtx (rtx, struct mapping *, int);
+static bool uses_macro_p (rtx, struct mapping *);
+static const char *add_condition_to_string (const char *, const char *);
+static void add_condition_to_rtx (rtx, const char *);
+static int apply_macro_traverse (void **, void *);
+static struct mapping *add_mapping (struct macro_group *, htab_t t,
+				    const char *, FILE *);
+static struct map_value **add_map_value (struct map_value **,
+					 int, const char *);
+static void initialize_macros (void);
 static void read_name (char *, FILE *);
 static char *read_string (FILE *, int);
 static char *read_quoted_string (FILE *);
@@ -42,6 +109,16 @@ static hashval_t def_hash (const void *);
 static int def_name_eq_p (const void *, const void *);
 static void read_constants (FILE *infile, char *tmp_char);
 static void validate_const_int (FILE *, const char *);
+static int find_macro (struct macro_group *, const char *, FILE *);
+static struct mapping *read_mapping (struct macro_group *, htab_t, FILE *);
+static void check_code_macro (struct mapping *, FILE *);
+static rtx read_rtx_1 (FILE *);
+
+/* The mode and code macro structures.  */
+static struct macro_group modes, codes;
+
+/* Index I is the value of BELLWETHER_CODE (I + NUM_RTX_CODE).  */
+static enum rtx_code *bellwether_codes;
 
 /* Obstack used for allocating RTL strings.  */
 static struct obstack string_obstack;
@@ -97,6 +174,393 @@ fatal_expected_char (FILE *infile, int expected_c, int actual_c)
 			    expected_c, actual_c);
 }
 
+/* Implementations of the macro_group callbacks for modes.  */
+
+static int
+find_mode (const char *name, FILE *infile)
+{
+  int i;
+
+  for (i = 0; i < NUM_MACHINE_MODES; i++)
+    if (strcmp (GET_MODE_NAME (i), name) == 0)
+      return i;
+
+  fatal_with_file_and_line (infile, "unknown mode `%s'", name);
+}
+
+static bool
+uses_mode_macro_p (rtx x, int mode)
+{
+  return (int) GET_MODE (x) == mode;
+}
+
+static void
+apply_mode_macro (rtx x, int mode)
+{
+  PUT_MODE (x, mode);
+}
+
+/* Implementations of the macro_group callbacks for codes.  */
+
+static int
+find_code (const char *name, FILE *infile)
+{
+  int i;
+
+  for (i = 0; i < NUM_RTX_CODE; i++)
+    if (strcmp (GET_RTX_NAME (i), name) == 0)
+      return i;
+
+  fatal_with_file_and_line (infile, "unknown rtx code `%s'", name);
+}
+
+static bool
+uses_code_macro_p (rtx x, int code)
+{
+  return (int) GET_CODE (x) == code;
+}
+
+static void
+apply_code_macro (rtx x, int code)
+{
+  PUT_CODE (x, code);
+}
+
+/* Given that MACRO is being expanded as VALUE, apply the appropriate
+   string substitutions to STRING.  Return the new string if any changes
+   were needed, otherwise return STRING itself.  */
+
+static const char *
+apply_macro_to_string (const char *string, struct mapping *macro, int value)
+{
+  char *base, *copy, *p, *attr, *start, *end;
+  struct mapping *m;
+  struct map_value *v;
+
+  if (string == 0)
+    return string;
+
+  base = p = copy = ASTRDUP (string);
+  while ((start = index (p, '<')) && (end = index (start, '>')))
+    {
+      p = start + 1;
+
+      /* If there's a "macro:" prefix, check whether the macro name matches.
+	 Set ATTR to the start of the attribute name.  */
+      attr = index (p, ':');
+      if (attr == 0 || attr > end)
+	attr = p;
+      else
+	{
+	  if (strncmp (p, macro->name, attr - p) != 0
+	      || macro->name[attr - p] != 0)
+	    continue;
+	  attr++;
+	}
+
+      /* Find the attribute specification.  */
+      *end = 0;
+      m = (struct mapping *) htab_find (macro->group->attrs, &attr);
+      *end = '>';
+      if (m == 0)
+	continue;
+
+      /* Find the attribute value for VALUE.  */
+      for (v = m->values; v != 0; v = v->next)
+	if (v->number == value)
+	  break;
+      if (v == 0)
+	continue;
+
+      /* Add everything between the last copied byte and the '<',
+	 then add in the attribute value.  */
+      obstack_grow (&string_obstack, base, start - base);
+      obstack_grow (&string_obstack, v->string, strlen (v->string));
+      base = end + 1;
+    }
+  if (base != copy)
+    {
+      obstack_grow (&string_obstack, base, strlen (base) + 1);
+      return (char *) obstack_finish (&string_obstack);
+    }
+  return string;
+}
+
+/* Return a copy of ORIGINAL in which all uses of MACRO have been
+   replaced by VALUE.  */
+
+static rtx
+apply_macro_to_rtx (rtx original, struct mapping *macro, int value)
+{
+  struct macro_group *group;
+  const char *format_ptr;
+  int i, j;
+  rtx x;
+  enum rtx_code bellwether_code;
+
+  if (original == 0)
+    return original;
+
+  /* Create a shallow copy of ORIGINAL.  */
+  bellwether_code = BELLWETHER_CODE (GET_CODE (original));
+  x = rtx_alloc (bellwether_code);
+  memcpy (x, original, RTX_SIZE (bellwether_code));
+
+  /* Change the mode or code itself.  */
+  group = macro->group;
+  if (group->uses_macro_p (x, macro->index + group->num_builtins))
+    group->apply_macro (x, value);
+
+  /* Change each string and recursively change each rtx.  */
+  format_ptr = GET_RTX_FORMAT (bellwether_code);
+  for (i = 0; format_ptr[i] != 0; i++)
+    switch (format_ptr[i])
+      {
+      case 'S':
+      case 'T':
+      case 's':
+	XSTR (x, i) = apply_macro_to_string (XSTR (x, i), macro, value);
+	break;
+
+      case 'e':
+	XEXP (x, i) = apply_macro_to_rtx (XEXP (x, i), macro, value);
+	break;
+
+      case 'V':
+      case 'E':
+	if (XVEC (original, i))
+	  {
+	    XVEC (x, i) = rtvec_alloc (XVECLEN (original, i));
+	    for (j = 0; j < XVECLEN (x, i); j++)
+	      XVECEXP (x, i, j) = apply_macro_to_rtx (XVECEXP (original, i, j),
+						      macro, value);
+	  }
+	break;
+
+      default:
+	break;
+      }
+  return x;
+}
+
+/* Return true if X (or some subexpression of X) uses macro MACRO.  */
+
+static bool
+uses_macro_p (rtx x, struct mapping *macro)
+{
+  struct macro_group *group;
+  const char *format_ptr;
+  int i, j;
+
+  if (x == 0)
+    return false;
+
+  group = macro->group;
+  if (group->uses_macro_p (x, macro->index + group->num_builtins))
+    return true;
+
+  format_ptr = GET_RTX_FORMAT (BELLWETHER_CODE (GET_CODE (x)));
+  for (i = 0; format_ptr[i] != 0; i++)
+    switch (format_ptr[i])
+      {
+      case 'e':
+	if (uses_macro_p (XEXP (x, i), macro))
+	  return true;
+	break;
+
+      case 'V':
+      case 'E':
+	if (XVEC (x, i))
+	  for (j = 0; j < XVECLEN (x, i); j++)
+	    if (uses_macro_p (XVECEXP (x, i, j), macro))
+	      return true;
+	break;
+
+      default:
+	break;
+      }
+  return false;
+}
+
+/* Return a condition that must satisfy both ORIGINAL and EXTRA.  If ORIGINAL
+   has the form "&& ..." (as used in define_insn_and_splits), assume that
+   EXTRA is already satisfied.  Empty strings are treated like "true".  */
+
+static const char *
+add_condition_to_string (const char *original, const char *extra)
+{
+  char *result;
+
+  if (original == 0 || original[0] == 0)
+    return extra;
+
+  if ((original[0] == '&' && original[1] == '&') || extra[0] == 0)
+    return original;
+
+  asprintf (&result, "(%s) && (%s)", original, extra);
+  return result;
+}
+
+/* Like add_condition, but applied to all conditions in rtx X.  */
+
+static void
+add_condition_to_rtx (rtx x, const char *extra)
+{
+  switch (GET_CODE (x))
+    {
+    case DEFINE_INSN:
+    case DEFINE_EXPAND:
+      XSTR (x, 2) = add_condition_to_string (XSTR (x, 2), extra);
+      break;
+
+    case DEFINE_SPLIT:
+    case DEFINE_PEEPHOLE:
+    case DEFINE_PEEPHOLE2:
+    case DEFINE_COND_EXEC:
+      XSTR (x, 1) = add_condition_to_string (XSTR (x, 1), extra);
+      break;
+
+    case DEFINE_INSN_AND_SPLIT:
+      XSTR (x, 2) = add_condition_to_string (XSTR (x, 2), extra);
+      XSTR (x, 4) = add_condition_to_string (XSTR (x, 4), extra);
+      break;
+
+    default:
+      break;
+    }
+}
+
+/* A htab_traverse callback.  Search the EXPR_LIST given by DATA
+   for rtxes that use the macro in *SLOT.  Replace each such rtx
+   with a list of expansions.  */
+
+static int
+apply_macro_traverse (void **slot, void *data)
+{
+  struct mapping *macro;
+  struct map_value *v;
+  rtx elem, new_elem, original, x;
+
+  macro = (struct mapping *) *slot;
+  for (elem = (rtx) data; elem != 0; elem = XEXP (elem, 1))
+    if (uses_macro_p (XEXP (elem, 0), macro))
+      {
+	original = XEXP (elem, 0);
+	for (v = macro->values; v != 0; v = v->next)
+	  {
+	    x = apply_macro_to_rtx (original, macro, v->number);
+	    add_condition_to_rtx (x, v->string);
+	    if (v != macro->values)
+	      {
+		/* Insert a new EXPR_LIST node after ELEM and put the
+		   new expansion there.  */
+		new_elem = rtx_alloc (EXPR_LIST);
+		XEXP (new_elem, 1) = XEXP (elem, 1);
+		XEXP (elem, 1) = new_elem;
+		elem = new_elem;
+	      }
+	    XEXP (elem, 0) = x;
+	  }
+    }
+  return 1;
+}
+
+/* Add a new "mapping" structure to hashtable TABLE.  NAME is the name
+   of the mapping, GROUP is the group to which it belongs, and INFILE
+   is the file that defined the mapping.  */
+
+static struct mapping *
+add_mapping (struct macro_group *group, htab_t table,
+	     const char *name, FILE *infile)
+{
+  struct mapping *m;
+  void **slot;
+
+  m = XNEW (struct mapping);
+  m->name = xstrdup (name);
+  m->group = group;
+  m->index = htab_elements (table);
+  m->values = 0;
+
+  slot = htab_find_slot (table, m, INSERT);
+  if (*slot != 0)
+    fatal_with_file_and_line (infile, "`%s' already defined", name);
+
+  *slot = m;
+  return m;
+}
+
+/* Add the pair (NUMBER, STRING) to a list of map_value structures.
+   END_PTR points to the current null terminator for the list; return
+   a pointer the new null terminator.  */
+
+static struct map_value **
+add_map_value (struct map_value **end_ptr, int number, const char *string)
+{
+  struct map_value *value;
+
+  value = XNEW (struct map_value);
+  value->next = 0;
+  value->number = number;
+  value->string = string;
+
+  *end_ptr = value;
+  return &value->next;
+}
+
+/* Do one-time initialization of the mode and code attributes.  */
+
+static void
+initialize_macros (void)
+{
+  struct mapping *lower, *upper;
+  struct map_value **lower_ptr, **upper_ptr;
+  char *copy, *p;
+  int i;
+
+  modes.attrs = htab_create (13, def_hash, def_name_eq_p, 0);
+  modes.macros = htab_create (13, def_hash, def_name_eq_p, 0);
+  modes.num_builtins = MAX_MACHINE_MODE;
+  modes.find_builtin = find_mode;
+  modes.uses_macro_p = uses_mode_macro_p;
+  modes.apply_macro = apply_mode_macro;
+
+  codes.attrs = htab_create (13, def_hash, def_name_eq_p, 0);
+  codes.macros = htab_create (13, def_hash, def_name_eq_p, 0);
+  codes.num_builtins = NUM_RTX_CODE;
+  codes.find_builtin = find_code;
+  codes.uses_macro_p = uses_code_macro_p;
+  codes.apply_macro = apply_code_macro;
+
+  lower = add_mapping (&modes, modes.attrs, "mode", 0);
+  upper = add_mapping (&modes, modes.attrs, "MODE", 0);
+  lower_ptr = &lower->values;
+  upper_ptr = &upper->values;
+  for (i = 0; i < MAX_MACHINE_MODE; i++)
+    {
+      copy = xstrdup (GET_MODE_NAME (i));
+      for (p = copy; *p != 0; p++)
+	*p = TOLOWER (*p);
+
+      upper_ptr = add_map_value (upper_ptr, i, GET_MODE_NAME (i));
+      lower_ptr = add_map_value (lower_ptr, i, copy);
+    }
+
+  lower = add_mapping (&codes, codes.attrs, "code", 0);
+  upper = add_mapping (&codes, codes.attrs, "CODE", 0);
+  lower_ptr = &lower->values;
+  upper_ptr = &upper->values;
+  for (i = 0; i < NUM_RTX_CODE; i++)
+    {
+      copy = xstrdup (GET_RTX_NAME (i));
+      for (p = copy; *p != 0; p++)
+	*p = TOUPPER (*p);
+
+      lower_ptr = add_map_value (lower_ptr, i, GET_RTX_NAME (i));
+      upper_ptr = add_map_value (upper_ptr, i, copy);
+    }
+}
+
 /* Read chars from INFILE until a non-whitespace char
    and return that.  Comments, both Lisp style and C style,
    are treated as whitespace.
@@ -398,24 +862,26 @@ atoll (const char *p)
 }
 #endif
 
-/* Given a constant definition, return a hash code for its name.  */
+/* Given an object that starts with a char * name field, return a hash
+   code for its name.  */
 static hashval_t
 def_hash (const void *def)
 {
   unsigned result, i;
-  const char *string = ((const struct md_constant *) def)->name;
+  const char *string = *(const char *const *) def;
 
-  for (result = i = 0;*string++ != '\0'; i++)
+  for (result = i = 0; *string++ != '\0'; i++)
     result += ((unsigned char) *string << (i % CHAR_BIT));
   return result;
 }
 
-/* Given two constant definitions, return true if they have the same name.  */
+/* Given two objects that start with char * name fields, return true if
+   they have the same name.  */
 static int
 def_name_eq_p (const void *def1, const void *def2)
 {
-  return ! strcmp (((const struct md_constant *) def1)->name,
-		   ((const struct md_constant *) def2)->name);
+  return ! strcmp (*(const char *const *) def1,
+		   *(const char *const *) def2);
 }
 
 /* INFILE is a FILE pointer to read text from.  TMP_CHAR is a buffer suitable
@@ -504,6 +970,102 @@ validate_const_int (FILE *infile, const char *string)
     fatal_with_file_and_line (infile, "invalid decimal constant \"%s\"\n", string);
 }
 
+/* Search GROUP for a mode or code called NAME and return its numerical
+   identifier.  INFILE is the file that contained NAME.  */
+
+static int
+find_macro (struct macro_group *group, const char *name, FILE *infile)
+{
+  struct mapping *m;
+
+  m = (struct mapping *) htab_find (group->macros, &name);
+  if (m != 0)
+    return m->index + group->num_builtins;
+  return group->find_builtin (name, infile);
+}
+
+/* Finish reading a declaration of the form:
+
+       (define... <name> [<value1> ... <valuen>])
+
+   from INFILE, where each <valuei> is either a bare symbol name or a
+   "(<name> <string>)" pair.  The "(define..." part has already been read.
+
+   Represent the declaration as a "mapping" structure; add it to TABLE
+   (which belongs to GROUP) and return it.  */
+
+static struct mapping *
+read_mapping (struct macro_group *group, htab_t table, FILE *infile)
+{
+  char tmp_char[256];
+  struct mapping *m;
+  struct map_value **end_ptr;
+  const char *string;
+  int number, c;
+
+  /* Read the mapping name and create a structure for it.  */
+  read_name (tmp_char, infile);
+  m = add_mapping (group, table, tmp_char, infile);
+
+  c = read_skip_spaces (infile);
+  if (c != '[')
+    fatal_expected_char (infile, '[', c);
+
+  /* Read each value.  */
+  end_ptr = &m->values;
+  c = read_skip_spaces (infile);
+  do
+    {
+      if (c != '(')
+	{
+	  /* A bare symbol name that is implicitly paired to an
+	     empty string.  */
+	  ungetc (c, infile);
+	  read_name (tmp_char, infile);
+	  string = "";
+	}
+      else
+	{
+	  /* A "(name string)" pair.  */
+	  read_name (tmp_char, infile);
+	  string = read_string (infile, false);
+	  c = read_skip_spaces (infile);
+	  if (c != ')')
+	    fatal_expected_char (infile, ')', c);
+	}
+      number = group->find_builtin (tmp_char, infile);
+      end_ptr = add_map_value (end_ptr, number, string);
+      c = read_skip_spaces (infile);
+    }
+  while (c != ']');
+
+  c = read_skip_spaces (infile);
+  if (c != ')')
+    fatal_expected_char (infile, ')', c);
+
+  return m;
+}
+
+/* Check newly-created code macro MACRO to see whether every code has the
+   same format.  Initialize the macro's entry in bellwether_codes.  */
+
+static void
+check_code_macro (struct mapping *macro, FILE *infile)
+{
+  struct map_value *v;
+  enum rtx_code bellwether;
+
+  bellwether = macro->values->number;
+  for (v = macro->values->next; v != 0; v = v->next)
+    if (strcmp (GET_RTX_FORMAT (bellwether), GET_RTX_FORMAT (v->number)) != 0)
+      fatal_with_file_and_line (infile, "code macro `%s' combines "
+				"different rtx formats", macro->name);
+
+  bellwether_codes = XRESIZEVEC (enum rtx_code, bellwether_codes,
+				 macro->index + 1);
+  bellwether_codes[macro->index] = bellwether;
+}
+
 /* Read an rtx in printed representation from INFILE
    and return an actual rtx in core constructed accordingly.
    read_rtx is not used in the compiler proper, but rather in
@@ -512,8 +1074,42 @@ validate_const_int (FILE *infile, const char *string)
 rtx
 read_rtx (FILE *infile)
 {
-  int i, j;
-  RTX_CODE tmp_code;
+  static rtx queue_head, queue_next;
+  rtx return_rtx;
+
+  /* Do one-time initialization.  */
+  if (queue_head == 0)
+    {
+      initialize_macros ();
+      obstack_init (&string_obstack);
+      queue_head = rtx_alloc (EXPR_LIST);
+    }
+
+  if (queue_next == 0)
+    {
+      queue_next = queue_head;
+
+      XEXP (queue_next, 0) = read_rtx_1 (infile);
+      XEXP (queue_next, 1) = 0;
+
+      htab_traverse (modes.macros, apply_macro_traverse, queue_next);
+      htab_traverse (codes.macros, apply_macro_traverse, queue_next);
+    }
+
+  return_rtx = XEXP (queue_next, 0);
+  queue_next = XEXP (queue_next, 1);
+
+  return return_rtx;
+}
+
+/* Subroutine of read_rtx that reads one construct from INFILE but
+   doesn't apply any macros.  */
+
+static rtx
+read_rtx_1 (FILE *infile)
+{
+  int i;
+  RTX_CODE real_code, bellwether_code;
   const char *format_ptr;
   /* tmp_char is a buffer used for reading decimal integers
      and names of rtx types and machine modes.
@@ -524,8 +1120,6 @@ read_rtx (FILE *infile)
   int tmp_int;
   HOST_WIDE_INT tmp_wide;
 
-  static int initialized;
-
   /* Linked list structure for making RTXs: */
   struct rtx_list
     {
@@ -533,51 +1127,52 @@ read_rtx (FILE *infile)
       rtx value;		/* Value of this node.  */
     };
 
-  if (!initialized)
-    {
-      obstack_init (&string_obstack);
-      initialized = 1;
-    }
-
-again:
+ again:
   c = read_skip_spaces (infile); /* Should be open paren.  */
   if (c != '(')
     fatal_expected_char (infile, '(', c);
 
   read_name (tmp_char, infile);
-
-  tmp_code = UNKNOWN;
-  for (i = 0; i < NUM_RTX_CODE; i++)
-    if (! strcmp (tmp_char, GET_RTX_NAME (i)))
-      {
-	tmp_code = (RTX_CODE) i;	/* get value for name */
-	break;
-      }
-
-  if (tmp_code == UNKNOWN)
+  if (strcmp (tmp_char, "nil") == 0)
     {
       /* (nil) stands for an expression that isn't there.  */
-      if (! strcmp (tmp_char, "nil"))
-	{
-	  /* Discard the closeparen.  */
-	  c = read_skip_spaces (infile);
-	  if (c != ')')
-	    fatal_expected_char (infile, ')', c);
-	  return 0;
-	}
-      /* (define_constants ...) has special syntax.  */
-      else if (! strcmp (tmp_char, "define_constants"))
-	{
-	  read_constants (infile, tmp_char);
-	  goto again;
-	}
-      else 
-	fatal_with_file_and_line (infile, "unknown rtx code `%s'", tmp_char);
+      c = read_skip_spaces (infile);
+      if (c != ')')
+	fatal_expected_char (infile, ')', c);
+      return 0;
+    }
+  if (strcmp (tmp_char, "define_constants") == 0)
+    {
+      read_constants (infile, tmp_char);
+      goto again;
+    }
+  if (strcmp (tmp_char, "define_mode_attr") == 0)
+    {
+      read_mapping (&modes, modes.attrs, infile);
+      goto again;
+    }
+  if (strcmp (tmp_char, "define_mode_macro") == 0)
+    {
+      read_mapping (&modes, modes.macros, infile);
+      goto again;
+    }
+  if (strcmp (tmp_char, "define_code_attr") == 0)
+    {
+      read_mapping (&codes, codes.attrs, infile);
+      goto again;
+    }
+  if (strcmp (tmp_char, "define_code_macro") == 0)
+    {
+      check_code_macro (read_mapping (&codes, codes.macros, infile), infile);
+      goto again;
     }
+  real_code = find_macro (&codes, tmp_char, infile);
+  bellwether_code = BELLWETHER_CODE (real_code);
 
   /* If we end up with an insn expression then we free this space below.  */
-  return_rtx = rtx_alloc (tmp_code);
-  format_ptr = GET_RTX_FORMAT (GET_CODE (return_rtx));
+  return_rtx = rtx_alloc (bellwether_code);
+  format_ptr = GET_RTX_FORMAT (bellwether_code);
+  PUT_CODE (return_rtx, real_code);
 
   /* If what follows is `: mode ', read it and
      store the mode in the rtx.  */
@@ -586,14 +1181,7 @@ again:
   if (i == ':')
     {
       read_name (tmp_char, infile);
-      for (j = 0; j < NUM_MACHINE_MODES; j++)
-	if (! strcmp (GET_MODE_NAME (j), tmp_char))
-	  break;
-
-      if (j == MAX_MACHINE_MODE)
-	fatal_with_file_and_line (infile, "unknown mode `%s'", tmp_char);
-
-      PUT_MODE (return_rtx, (enum machine_mode) j);
+      PUT_MODE (return_rtx, find_macro (&modes, tmp_char, infile));
     }
   else
     ungetc (i, infile);
@@ -608,7 +1196,7 @@ again:
 
       case 'e':
       case 'u':
-	XEXP (return_rtx, i) = read_rtx (infile);
+	XEXP (return_rtx, i) = read_rtx_1 (infile);
 	break;
 
       case 'V':
@@ -640,7 +1228,7 @@ again:
 	    {
 	      ungetc (c, infile);
 	      list_counter++;
-	      obstack_ptr_grow (&vector_stack, read_rtx (infile));
+	      obstack_ptr_grow (&vector_stack, read_rtx_1 (infile));
 	    }
 	  if (list_counter > 0)
 	    {