/* Support routines for the various generation passes.
Copyright (C) 2000 Free Software Foundation, Inc.
This file is part of GNU CC.
GNU CC 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 2, or (at your option)
any later version.
GNU CC 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 GNU CC; see the file COPYING. If not, write to
the Free Software Foundation, 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include "hconfig.h"
#include "system.h"
#include "rtl.h"
#include "obstack.h"
#include "errors.h"
#include "gensupport.h"
static struct obstack obstack;
struct obstack *rtl_obstack = &obstack;
#define obstack_chunk_alloc xmalloc
#define obstack_chunk_free free
static int sequence_num;
static int errors;
static int predicable_default;
static const char *predicable_true;
static const char *predicable_false;
/* We initially queue all patterns, process the define_insn and
define_cond_exec patterns, then return them one at a time. */
struct queue_elem
{
rtx data;
int lineno;
struct queue_elem *next;
};
static struct queue_elem *define_attr_queue;
static struct queue_elem **define_attr_tail = &define_attr_queue;
static struct queue_elem *define_insn_queue;
static struct queue_elem **define_insn_tail = &define_insn_queue;
static struct queue_elem *define_cond_exec_queue;
static struct queue_elem **define_cond_exec_tail = &define_cond_exec_queue;
static struct queue_elem *other_queue;
static struct queue_elem **other_tail = &other_queue;
static void queue_pattern PARAMS ((rtx, struct queue_elem ***, int));
static void remove_constraints PARAMS ((rtx));
static void process_rtx PARAMS ((rtx, int));
static int is_predicable PARAMS ((struct queue_elem *));
static void identify_predicable_attribute PARAMS ((void));
static int n_alternatives PARAMS ((const char *));
static void collect_insn_data PARAMS ((rtx, int *, int *));
static rtx alter_predicate_for_insn PARAMS ((rtx, int, int, int));
static const char *alter_test_for_insn PARAMS ((struct queue_elem *,
struct queue_elem *));
static char *shift_output_template PARAMS ((char *, const char *, int));
static const char *alter_output_for_insn PARAMS ((struct queue_elem *,
struct queue_elem *,
int, int));
static void process_one_cond_exec PARAMS ((struct queue_elem *));
static void process_define_cond_exec PARAMS ((void));
void
message_with_line VPARAMS ((int lineno, const char *msg, ...))
{
#ifndef ANSI_PROTOTYPES
int lineno;
const char *msg;
#endif
va_list ap;
VA_START (ap, msg);
#ifndef ANSI_PROTOTYPES
lineno = va_arg (ap, int);
msg = va_arg (ap, const char *);
#endif
fprintf (stderr, "%s:%d: ", read_rtx_filename, lineno);
vfprintf (stderr, msg, ap);
fputc ('\n', stderr);
va_end (ap);
}
/* Queue PATTERN on LIST_TAIL. */
static void
queue_pattern (pattern, list_tail, lineno)
rtx pattern;
struct queue_elem ***list_tail;
int lineno;
{
struct queue_elem *e = (struct queue_elem *) xmalloc (sizeof (*e));
e->data = pattern;
e->lineno = lineno;
e->next = NULL;
**list_tail = e;
*list_tail = &e->next;
}
/* Recursively remove constraints from an rtx. */
static void
remove_constraints (part)
rtx part;
{
register int i, j;
register const char *format_ptr;
if (part == 0)
return;
if (GET_CODE (part) == MATCH_OPERAND)
XSTR (part, 2) = "";
else if (GET_CODE (part) == MATCH_SCRATCH)
XSTR (part, 1) = "";
format_ptr = GET_RTX_FORMAT (GET_CODE (part));
for (i = 0; i < GET_RTX_LENGTH (GET_CODE (part)); i++)
switch (*format_ptr++)
{
case 'e':
case 'u':
remove_constraints (XEXP (part, i));
break;
case 'E':
if (XVEC (part, i) != NULL)
for (j = 0; j < XVECLEN (part, i); j++)
remove_constraints (XVECEXP (part, i, j));
break;
}
}
/* Process a top level rtx in some way, queueing as appropriate. */
static void
process_rtx (desc, lineno)
rtx desc;
int lineno;
{
switch (GET_CODE (desc))
{
case DEFINE_INSN:
queue_pattern (desc, &define_insn_tail, lineno);
break;
case DEFINE_COND_EXEC:
queue_pattern (desc, &define_cond_exec_tail, lineno);
break;
case DEFINE_ATTR:
queue_pattern (desc, &define_attr_tail, lineno);
break;
case DEFINE_INSN_AND_SPLIT:
{
const char *split_cond;
rtx split;
int i;
/* Create a split with values from the insn_and_split. */
split = rtx_alloc (DEFINE_SPLIT);
i = XVECLEN (desc, 1);
XEXP (split, 0) = rtvec_alloc (i);
while (--i >= 0)
{
XVECEXP (split, 0, i) = copy_rtx (XVECEXP (desc, 1, i));
remove_constraints (XVECEXP (split, 0, i));
}
/* If the split condition starts with "&&", append it to the
insn condition to create the new split condition. */
split_cond = XSTR (desc, 4);
if (split_cond[0] == '&' && split_cond[1] == '&')
{
const char *insn_cond = XSTR (desc, 2);
size_t insn_cond_len = strlen (insn_cond);
size_t split_cond_len = strlen (split_cond);
char *combined;
combined = (char *) xmalloc (insn_cond_len + split_cond_len + 1);
memcpy (combined, insn_cond, insn_cond_len);
memcpy (combined + insn_cond_len, split_cond, split_cond_len + 1);
split_cond = combined;
}
XSTR (split, 1) = split_cond;
XVEC (split, 2) = XVEC (desc, 5);
XSTR (split, 3) = XSTR (desc, 6);
/* Fix up the DEFINE_INSN. */
PUT_CODE (desc, DEFINE_INSN);
XVEC (desc, 4) = XVEC (desc, 7);
/* Queue them. */
queue_pattern (desc, &define_insn_tail, lineno);
queue_pattern (split, &other_tail, lineno);
break;
}
default:
queue_pattern (desc, &other_tail, lineno);
break;
}
}
/* Return true if attribute PREDICABLE is true for ELEM, which holds
a DEFINE_INSN. */
static int
is_predicable (elem)
struct queue_elem *elem;
{
rtvec vec = XVEC (elem->data, 4);
const char *value;
int i;
if (! vec)
return predicable_default;
for (i = GET_NUM_ELEM (vec) - 1; i >= 0; --i)
{
rtx sub = RTVEC_ELT (vec, i);
switch (GET_CODE (sub))
{
case SET_ATTR:
if (strcmp (XSTR (sub, 0), "predicable") == 0)
{
value = XSTR (sub, 1);
goto found;
}
break;
case SET_ATTR_ALTERNATIVE:
if (strcmp (XSTR (sub, 0), "predicable") == 0)
{
message_with_line (elem->lineno,
"multiple alternatives for `predicable'");
errors = 1;
return 0;
}
break;
case SET:
if (GET_CODE (SET_DEST (sub)) != ATTR
|| strcmp (XSTR (SET_DEST (sub), 0), "predicable") != 0)
break;
sub = SET_SRC (sub);
if (GET_CODE (sub) == CONST_STRING)
{
value = XSTR (sub, 0);
goto found;
}
/* ??? It would be possible to handle this if we really tried.
It's not easy though, and I'm not going to bother until it
really proves necessary. */
message_with_line (elem->lineno,
"non-constant value for `predicable'");
errors = 1;
return 0;
default:
abort ();
}
}
return predicable_default;
found:
/* Verify that predicability does not vary on the alternative. */
/* ??? It should be possible to handle this by simply eliminating
the non-predicable alternatives from the insn. FRV would like
to do this. Delay this until we've got the basics solid. */
if (strchr (value, ',') != NULL)
{
message_with_line (elem->lineno,
"multiple alternatives for `predicable'");
errors = 1;
return 0;
}
/* Find out which value we're looking at. */
if (strcmp (value, predicable_true) == 0)
return 1;
if (strcmp (value, predicable_false) == 0)
return 0;
message_with_line (elem->lineno,
"Unknown value `%s' for `predicable' attribute",
value);
errors = 1;
return 0;
}
/* Examine the attribute "predicable"; discover its boolean values
and its default. */
static void
identify_predicable_attribute ()
{
struct queue_elem *elem;
char *true, *false;
const char *value;
size_t len;
/* Look for the DEFINE_ATTR for `predicable', which must exist. */
for (elem = define_attr_queue; elem ; elem = elem->next)
if (strcmp (XSTR (elem->data, 0), "predicable") == 0)
goto found;
message_with_line (define_cond_exec_queue->lineno,
"Attribute `predicable' not defined");
errors = 1;
return;
found:
value = XSTR (elem->data, 1);
len = strlen (value);
false = (char *) xmalloc (len + 1);
memcpy (false, value, len + 1);
true = strchr (false, ',');
if (true == NULL || strchr (++true, ',') != NULL)
{
message_with_line (elem->lineno,
"Attribute `predicable' is not a boolean");
errors = 1;
return;
}
true[-1] = '\0';
predicable_true = true;
predicable_false = false;
switch (GET_CODE (XEXP (elem->data, 2)))
{
case CONST_STRING:
value = XSTR (XEXP (elem->data, 2), 0);
break;
case CONST:
message_with_line (elem->lineno,
"Attribute `predicable' cannot be const");
errors = 1;
return;
default:
message_with_line (elem->lineno,
"Attribute `predicable' must have a constant default");
errors = 1;
return;
}
if (strcmp (value, true) == 0)
predicable_default = 1;
else if (strcmp (value, false) == 0)
predicable_default = 0;
else
{
message_with_line (elem->lineno,
"Unknown value `%s' for `predicable' attribute",
value);
errors = 1;
}
}
/* Return the number of alternatives in constraint S. */
static int
n_alternatives (s)
const char *s;
{
int n = 1;
if (s)
while (*s)
n += (*s++ == ',');
return n;
}
/* Determine how many alternatives there are in INSN, and how many
operands. */
static void
collect_insn_data (pattern, palt, pmax)
rtx pattern;
int *palt, *pmax;
{
const char *fmt;
enum rtx_code code;
int i, j, len;
code = GET_CODE (pattern);
switch (code)
{
case MATCH_OPERAND:
*palt = n_alternatives (XSTR (pattern, 2));
/* FALLTHRU */
case MATCH_OPERATOR:
case MATCH_SCRATCH:
case MATCH_PARALLEL:
case MATCH_INSN:
i = XINT (pattern, 0);
if (i > *pmax)
*pmax = i;
break;
default:
break;
}
fmt = GET_RTX_FORMAT (code);
len = GET_RTX_LENGTH (code);
for (i = 0; i < len; i++)
{
switch (fmt[i])
{
case 'e': case 'u':
collect_insn_data (XEXP (pattern, i), palt, pmax);
break;
case 'V':
if (XVEC (pattern, i) == NULL)
break;
/* FALLTHRU */
case 'E':
for (j = XVECLEN (pattern, i) - 1; j >= 0; --j)
collect_insn_data (XVECEXP (pattern, i, j), palt, pmax);
break;
case 'i': case 'w': case '0': case 's': case 'S':
break;
default:
abort ();
}
}
}
static rtx
alter_predicate_for_insn (pattern, alt, max_op, lineno)
rtx pattern;
int alt, max_op, lineno;
{
const char *fmt;
enum rtx_code code;
int i, j, len;
code = GET_CODE (pattern);
switch (code)
{
case MATCH_OPERAND:
{
const char *c = XSTR (pattern, 2);
if (n_alternatives (c) != 1)
{
message_with_line (lineno,
"Too many alternatives for operand %d",
XINT (pattern, 0));
errors = 1;
return NULL;
}
/* Replicate C as needed to fill out ALT alternatives. */
if (c && *c && alt > 1)
{
size_t c_len = strlen (c);
size_t len = alt * (c_len + 1);
char *new_c = (char *) xmalloc (len);
memcpy (new_c, c, c_len);
for (i = 1; i < alt; ++i)
{
new_c[i * (c_len + 1) - 1] = ',';
memcpy (&new_c[i * (c_len + 1)], c, c_len);
}
new_c[len - 1] = '\0';
XSTR (pattern, 2) = new_c;
}
}
/* FALLTHRU */
case MATCH_OPERATOR:
case MATCH_SCRATCH:
case MATCH_PARALLEL:
case MATCH_INSN:
XINT (pattern, 0) += max_op;
break;
default:
break;
}
fmt = GET_RTX_FORMAT (code);
len = GET_RTX_LENGTH (code);
for (i = 0; i < len; i++)
{
rtx r;
switch (fmt[i])
{
case 'e': case 'u':
r = alter_predicate_for_insn (XEXP (pattern, i), alt,
max_op, lineno);
if (r == NULL)
return r;
break;
case 'E':
for (j = XVECLEN (pattern, i) - 1; j >= 0; --j)
{
r = alter_predicate_for_insn (XVECEXP (pattern, i, j),
alt, max_op, lineno);
if (r == NULL)
return r;
}
break;
case 'i': case 'w': case '0': case 's':
break;
default:
abort ();
}
}
return pattern;
}
static const char *
alter_test_for_insn (ce_elem, insn_elem)
struct queue_elem *ce_elem, *insn_elem;
{
const char *ce_test, *insn_test;
char *new_test;
size_t len, ce_len, insn_len;
ce_test = XSTR (ce_elem->data, 1);
insn_test = XSTR (insn_elem->data, 2);
if (!ce_test || *ce_test == '\0')
return insn_test;
if (!insn_test || *insn_test == '\0')
return ce_test;
ce_len = strlen (ce_test);
insn_len = strlen (insn_test);
len = 1 + ce_len + 1 + 4 + 1 + insn_len + 1 + 1;
new_test = (char *) xmalloc (len);
sprintf (new_test, "(%s) && (%s)", ce_test, insn_test);
return new_test;
}
/* Adjust all of the operand numbers in OLD to match the shift they'll
get from an operand displacement of DISP. Return a pointer after the
adjusted string. */
static char *
shift_output_template (new, old, disp)
char *new;
const char *old;
int disp;
{
while (*old)
{
char c = *old++;
*new++ = c;
if (c == '%')
{
c = *old++;
if (ISDIGIT ((unsigned char) c))
c += disp;
else if (ISUPPER ((unsigned char) c)
|| ISLOWER ((unsigned char) c))
{
*new++ = c;
c = *old++ + disp;
}
*new++ = c;
}
}
return new;
}
static const char *
alter_output_for_insn (ce_elem, insn_elem, alt, max_op)
struct queue_elem *ce_elem, *insn_elem;
int alt, max_op;
{
const char *ce_out, *insn_out;
char *new, *p;
size_t len, ce_len, insn_len;
/* ??? Could coordinate with genoutput to not duplicate code here. */
ce_out = XSTR (ce_elem->data, 2);
insn_out = XSTR (insn_elem->data, 3);
if (!ce_out || *ce_out == '\0')
return insn_out;
ce_len = strlen (ce_out);
insn_len = strlen (insn_out);
if (*insn_out == '*')
/* You must take care of the predicate yourself. */
return insn_out;
if (*insn_out == '@')
{
len = (ce_len + 1) * alt + insn_len + 1;
p = new = xmalloc (len);
do
{
do
*p++ = *insn_out++;
while (ISSPACE ((unsigned char) *insn_out));
if (*insn_out != '#')
{
p = shift_output_template (p, ce_out, max_op);
*p++ = ' ';
}
do
*p++ = *insn_out++;
while (*insn_out && *insn_out != '\n');
}
while (*insn_out);
*p = '\0';
}
else
{
len = ce_len + 1 + insn_len + 1;
new = xmalloc (len);
p = shift_output_template (new, ce_out, max_op);
*p++ = ' ';
memcpy (p, insn_out, insn_len + 1);
}
return new;
}
/* Replicate insns as appropriate for the given DEFINE_COND_EXEC. */
static void
process_one_cond_exec (ce_elem)
struct queue_elem *ce_elem;
{
struct queue_elem *insn_elem;
for (insn_elem = define_insn_queue; insn_elem ; insn_elem = insn_elem->next)
{
int alternatives, max_operand;
rtx pred, insn, pattern;
if (! is_predicable (insn_elem))
continue;
alternatives = 1;
max_operand = -1;
collect_insn_data (insn_elem->data, &alternatives, &max_operand);
max_operand += 1;
if (XVECLEN (ce_elem->data, 0) != 1)
{
message_with_line (ce_elem->lineno,
"too many patterns in predicate");
errors = 1;
return;
}
pred = copy_rtx (XVECEXP (ce_elem->data, 0, 0));
pred = alter_predicate_for_insn (pred, alternatives, max_operand,
ce_elem->lineno);
if (pred == NULL)
return;
/* Construct a new pattern for the new insn. */
insn = copy_rtx (insn_elem->data);
XSTR (insn, 0) = "";
pattern = rtx_alloc (COND_EXEC);
XEXP (pattern, 0) = pred;
if (XVECLEN (insn, 1) == 1)
{
XEXP (pattern, 1) = XVECEXP (insn, 1, 0);
XVECEXP (insn, 1, 0) = pattern;
PUT_NUM_ELEM (XVEC (insn, 1), 1);
}
else
{
XEXP (pattern, 1) = rtx_alloc (PARALLEL);
XVEC (XEXP (pattern, 1), 0) = XVEC (insn, 1);
XVEC (insn, 1) = rtvec_alloc (1);
XVECEXP (insn, 1, 0) = pattern;
}
XSTR (insn, 2) = alter_test_for_insn (ce_elem, insn_elem);
XSTR (insn, 3) = alter_output_for_insn (ce_elem, insn_elem,
alternatives, max_operand);
/* ??? Set `predicable' to false. Not crucial since it's really
only used here, and we won't reprocess this new pattern. */
/* Put the new pattern on the `other' list so that it
(a) is not reprocessed by other define_cond_exec patterns
(b) appears after all normal define_insn patterns.
??? B is debatable. If one has normal insns that match
cond_exec patterns, they will be preferred over these
generated patterns. Whether this matters in practice, or if
it's a good thing, or whether we should thread these new
patterns into the define_insn chain just after their generator
is something we'll have to experiment with. */
queue_pattern (insn, &other_tail, insn_elem->lineno);
}
}
/* If we have any DEFINE_COND_EXEC patterns, expand the DEFINE_INSN
patterns appropriately. */
static void
process_define_cond_exec ()
{
struct queue_elem *elem;
identify_predicable_attribute ();
if (errors)
return;
for (elem = define_cond_exec_queue; elem ; elem = elem->next)
process_one_cond_exec (elem);
}
/* The entry point for initializing the reader. */
int
init_md_reader (filename)
const char *filename;
{
FILE *input_file;
int c;
read_rtx_filename = filename;
input_file = fopen (filename, "r");
if (input_file == 0)
{
perror (filename);
return FATAL_EXIT_CODE;
}
obstack_init (rtl_obstack);
errors = 0;
sequence_num = 0;
/* Read the entire file. */
while (1)
{
rtx desc;
int lineno;
c = read_skip_spaces (input_file);
if (c == EOF)
break;
ungetc (c, input_file);
lineno = read_rtx_lineno;
desc = read_rtx (input_file);
process_rtx (desc, lineno);
}
fclose (input_file);
/* Process define_cond_exec patterns. */
if (define_cond_exec_queue != NULL)
process_define_cond_exec ();
return errors ? FATAL_EXIT_CODE : SUCCESS_EXIT_CODE;
}
/* The entry point for reading a single rtx from an md file. */
rtx
read_md_rtx (lineno, seqnr)
int *lineno;
int *seqnr;
{
struct queue_elem **queue, *elem;
rtx desc;
/* Read all patterns from a given queue before moving on to the next. */
if (define_attr_queue != NULL)
queue = &define_attr_queue;
else if (define_insn_queue != NULL)
queue = &define_insn_queue;
else if (other_queue != NULL)
queue = &other_queue;
else
return NULL_RTX;
elem = *queue;
*queue = elem->next;
desc = elem->data;
*lineno = elem->lineno;
*seqnr = sequence_num;
free (elem);
switch (GET_CODE (desc))
{
case DEFINE_INSN:
case DEFINE_EXPAND:
case DEFINE_SPLIT:
case DEFINE_PEEPHOLE:
case DEFINE_PEEPHOLE2:
sequence_num++;
break;
default:
break;
}
return desc;
}