ae90e6a355
From-SVN: r202
490 lines
12 KiB
C
490 lines
12 KiB
C
/* Generate code from machine description to perform peephole optimizations.
|
||
Copyright (C) 1987, 1989, 1992 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, 675 Mass Ave, Cambridge, MA 02139, USA. */
|
||
|
||
|
||
#include <stdio.h>
|
||
#include "config.h"
|
||
#include "rtl.h"
|
||
#include "obstack.h"
|
||
|
||
static struct obstack obstack;
|
||
struct obstack *rtl_obstack = &obstack;
|
||
|
||
#define obstack_chunk_alloc xmalloc
|
||
#define obstack_chunk_free free
|
||
|
||
extern void free ();
|
||
|
||
/* While tree-walking an instruction pattern, we keep a chain
|
||
of these `struct link's to record how to get down to the
|
||
current position. In each one, POS is the operand number,
|
||
and if the operand is a vector VEC is the element number.
|
||
VEC is -1 if the operand is not a vector. */
|
||
|
||
struct link
|
||
{
|
||
struct link *next;
|
||
int pos;
|
||
int vecelt;
|
||
};
|
||
|
||
char *xmalloc ();
|
||
static void match_rtx ();
|
||
static void gen_exp ();
|
||
static void fatal ();
|
||
void fancy_abort ();
|
||
|
||
static int max_opno;
|
||
|
||
/* Number of operands used in current peephole definition. */
|
||
|
||
static int n_operands;
|
||
|
||
/* Peephole optimizations get insn codes just like insn patterns.
|
||
Count them so we know the code of the define_peephole we are handling. */
|
||
|
||
static int insn_code_number = 0;
|
||
|
||
static void print_path ();
|
||
static void print_code ();
|
||
|
||
static void
|
||
gen_peephole (peep)
|
||
rtx peep;
|
||
{
|
||
int ninsns = XVECLEN (peep, 0);
|
||
int i;
|
||
|
||
n_operands = 0;
|
||
|
||
printf (" insn = ins1;\n");
|
||
#if 0
|
||
printf (" want_jump = 0;\n");
|
||
#endif
|
||
|
||
for (i = 0; i < ninsns; i++)
|
||
{
|
||
if (i > 0)
|
||
{
|
||
printf (" do { insn = NEXT_INSN (insn);\n");
|
||
printf (" if (insn == 0) goto L%d; }\n",
|
||
insn_code_number);
|
||
printf (" while (GET_CODE (insn) == NOTE\n");
|
||
printf ("\t || (GET_CODE (insn) == INSN\n");
|
||
printf ("\t && (GET_CODE (PATTERN (insn)) == USE\n");
|
||
printf ("\t\t || GET_CODE (PATTERN (insn)) == CLOBBER)));\n");
|
||
|
||
printf (" if (GET_CODE (insn) == CODE_LABEL\n\
|
||
|| GET_CODE (insn) == BARRIER)\n goto L%d;\n",
|
||
insn_code_number);
|
||
}
|
||
|
||
#if 0
|
||
printf (" if (GET_CODE (insn) == JUMP_INSN)\n");
|
||
printf (" want_jump = JUMP_LABEL (insn);\n");
|
||
#endif
|
||
|
||
printf (" pat = PATTERN (insn);\n");
|
||
|
||
/* Walk the insn's pattern, remembering at all times the path
|
||
down to the walking point. */
|
||
|
||
match_rtx (XVECEXP (peep, 0, i), 0, insn_code_number);
|
||
}
|
||
|
||
/* We get this far if the pattern matches.
|
||
Now test the extra condition. */
|
||
|
||
if (XSTR (peep, 1) && XSTR (peep, 1)[0])
|
||
printf (" if (! (%s)) goto L%d;\n",
|
||
XSTR (peep, 1), insn_code_number);
|
||
|
||
/* If that matches, construct new pattern and put it in the first insn.
|
||
This new pattern will never be matched.
|
||
It exists only so that insn-extract can get the operands back.
|
||
So use a simple regular form: a PARALLEL containing a vector
|
||
of all the operands. */
|
||
|
||
printf (" PATTERN (ins1) = gen_rtx (PARALLEL, VOIDmode, gen_rtvec_v (%d, operands));\n", n_operands);
|
||
|
||
#if 0
|
||
printf (" if (want_jump && GET_CODE (ins1) != JUMP_INSN)\n");
|
||
printf (" {\n");
|
||
printf (" rtx insn2 = emit_jump_insn_before (PATTERN (ins1), ins1);\n");
|
||
printf (" delete_insn (ins1);\n");
|
||
printf (" ins1 = ins2;\n");
|
||
printf (" }\n");
|
||
#endif
|
||
|
||
/* Record this define_peephole's insn code in the insn,
|
||
as if it had been recognized to match this. */
|
||
printf (" INSN_CODE (ins1) = %d;\n",
|
||
insn_code_number);
|
||
|
||
/* Delete the remaining insns. */
|
||
if (ninsns > 1)
|
||
printf (" delete_for_peephole (NEXT_INSN (ins1), insn);\n");
|
||
|
||
/* See reload1.c for insertion of NOTE which guarantees that this
|
||
cannot be zero. */
|
||
printf (" return NEXT_INSN (insn);\n");
|
||
|
||
printf (" L%d:\n\n", insn_code_number);
|
||
}
|
||
|
||
static void
|
||
match_rtx (x, path, fail_label)
|
||
rtx x;
|
||
struct link *path;
|
||
int fail_label;
|
||
{
|
||
register RTX_CODE code;
|
||
register int i;
|
||
register int len;
|
||
register char *fmt;
|
||
struct link link;
|
||
|
||
if (x == 0)
|
||
return;
|
||
|
||
|
||
code = GET_CODE (x);
|
||
|
||
switch (code)
|
||
{
|
||
case MATCH_OPERAND:
|
||
if (XINT (x, 0) > max_opno)
|
||
max_opno = XINT (x, 0);
|
||
if (XINT (x, 0) >= n_operands)
|
||
n_operands = 1 + XINT (x, 0);
|
||
|
||
printf (" x = ");
|
||
print_path (path);
|
||
printf (";\n");
|
||
|
||
printf (" operands[%d] = x;\n", XINT (x, 0));
|
||
if (XSTR (x, 1) && XSTR (x, 1)[0])
|
||
printf (" if (! %s (x, %smode)) goto L%d;\n",
|
||
XSTR (x, 1), GET_MODE_NAME (GET_MODE (x)), fail_label);
|
||
return;
|
||
|
||
case MATCH_DUP:
|
||
printf (" x = ");
|
||
print_path (path);
|
||
printf (";\n");
|
||
|
||
printf (" if (!rtx_equal_p (operands[%d], x)) goto L%d;\n",
|
||
XINT (x, 0), fail_label);
|
||
return;
|
||
|
||
case MATCH_OP_DUP:
|
||
printf (" x = ");
|
||
print_path (path);
|
||
printf (";\n");
|
||
|
||
printf (" if (GET_CODE (operands[%d]) != GET_CODE (x)\n", XINT (x, 0));
|
||
printf (" || GET_MODE (operands[%d]) != GET_MODE (x)) goto L%d;\n",
|
||
XINT (x, 0), fail_label);
|
||
printf (" operands[%d] = x;\n", XINT (x, 0));
|
||
link.next = path;
|
||
link.vecelt = -1;
|
||
for (i = 0; i < XVECLEN (x, 1); i++)
|
||
{
|
||
link.pos = i;
|
||
match_rtx (XVECEXP (x, 1, i), &link, fail_label);
|
||
}
|
||
return;
|
||
|
||
case MATCH_OPERATOR:
|
||
if (XINT (x, 0) > max_opno)
|
||
max_opno = XINT (x, 0);
|
||
if (XINT (x, 0) >= n_operands)
|
||
n_operands = 1 + XINT (x, 0);
|
||
|
||
printf (" x = ");
|
||
print_path (path);
|
||
printf (";\n");
|
||
|
||
printf (" operands[%d] = x;\n", XINT (x, 0));
|
||
if (XSTR (x, 1) && XSTR (x, 1)[0])
|
||
printf (" if (! %s (x, %smode)) goto L%d;\n",
|
||
XSTR (x, 1), GET_MODE_NAME (GET_MODE (x)), fail_label);
|
||
link.next = path;
|
||
link.vecelt = -1;
|
||
for (i = 0; i < XVECLEN (x, 2); i++)
|
||
{
|
||
link.pos = i;
|
||
match_rtx (XVECEXP (x, 2, i), &link, fail_label);
|
||
}
|
||
return;
|
||
|
||
case MATCH_PARALLEL:
|
||
if (XINT (x, 0) > max_opno)
|
||
max_opno = XINT (x, 0);
|
||
if (XINT (x, 0) >= n_operands)
|
||
n_operands = 1 + XINT (x, 0);
|
||
|
||
printf (" x = ");
|
||
print_path (path);
|
||
printf (";\n");
|
||
|
||
printf (" if (GET_CODE (x) != PARALLEL) goto L%d;\n", fail_label);
|
||
printf (" operands[%d] = x;\n", XINT (x, 0));
|
||
if (XSTR (x, 1) && XSTR (x, 1)[0])
|
||
printf (" if (! %s (x, %smode)) goto L%d;\n",
|
||
XSTR (x, 1), GET_MODE_NAME (GET_MODE (x)), fail_label);
|
||
link.next = path;
|
||
link.pos = 0;
|
||
for (i = 0; i < XVECLEN (x, 2); i++)
|
||
{
|
||
link.vecelt = i;
|
||
match_rtx (XVECEXP (x, 2, i), &link, fail_label);
|
||
}
|
||
return;
|
||
|
||
case ADDRESS:
|
||
match_rtx (XEXP (x, 0), path, fail_label);
|
||
return;
|
||
}
|
||
|
||
printf (" x = ");
|
||
print_path (path);
|
||
printf (";\n");
|
||
|
||
printf (" if (GET_CODE (x) != ");
|
||
print_code (code);
|
||
printf (") goto L%d;\n", fail_label);
|
||
|
||
if (GET_MODE (x) != VOIDmode)
|
||
{
|
||
printf (" if (GET_MODE (x) != %smode) goto L%d;\n",
|
||
GET_MODE_NAME (GET_MODE (x)), fail_label);
|
||
}
|
||
|
||
link.next = path;
|
||
link.vecelt = -1;
|
||
fmt = GET_RTX_FORMAT (code);
|
||
len = GET_RTX_LENGTH (code);
|
||
for (i = 0; i < len; i++)
|
||
{
|
||
link.pos = i;
|
||
if (fmt[i] == 'e' || fmt[i] == 'u')
|
||
match_rtx (XEXP (x, i), &link, fail_label);
|
||
else if (fmt[i] == 'E')
|
||
{
|
||
int j;
|
||
printf (" if (XVECLEN (x, %d) != %d) goto L%d;\n",
|
||
i, XVECLEN (x, i), fail_label);
|
||
for (j = 0; j < XVECLEN (x, i); j++)
|
||
{
|
||
link.vecelt = j;
|
||
match_rtx (XVECEXP (x, i, j), &link, fail_label);
|
||
}
|
||
}
|
||
else if (fmt[i] == 'i')
|
||
{
|
||
/* Make sure that at run time `x' is the RTX we want to test. */
|
||
if (i != 0)
|
||
{
|
||
printf (" x = ");
|
||
print_path (path);
|
||
printf (";\n");
|
||
}
|
||
|
||
printf (" if (XINT (x, %d) != %d) goto L%d;\n",
|
||
i, XINT (x, i), fail_label);
|
||
}
|
||
else if (fmt[i] == 's')
|
||
{
|
||
/* Make sure that at run time `x' is the RTX we want to test. */
|
||
if (i != 0)
|
||
{
|
||
printf (" x = ");
|
||
print_path (path);
|
||
printf (";\n");
|
||
}
|
||
|
||
printf (" if (strcmp (XSTR (x, %d), \"%s\")) goto L%d;\n",
|
||
i, XSTR (x, i), fail_label);
|
||
}
|
||
}
|
||
}
|
||
|
||
/* Given a PATH, representing a path down the instruction's
|
||
pattern from the root to a certain point, output code to
|
||
evaluate to the rtx at that point. */
|
||
|
||
static void
|
||
print_path (path)
|
||
struct link *path;
|
||
{
|
||
if (path == 0)
|
||
printf ("pat");
|
||
else if (path->vecelt >= 0)
|
||
{
|
||
printf ("XVECEXP (");
|
||
print_path (path->next);
|
||
printf (", %d, %d)", path->pos, path->vecelt);
|
||
}
|
||
else
|
||
{
|
||
printf ("XEXP (");
|
||
print_path (path->next);
|
||
printf (", %d)", path->pos);
|
||
}
|
||
}
|
||
|
||
static void
|
||
print_code (code)
|
||
RTX_CODE code;
|
||
{
|
||
register char *p1;
|
||
for (p1 = GET_RTX_NAME (code); *p1; p1++)
|
||
{
|
||
if (*p1 >= 'a' && *p1 <= 'z')
|
||
putchar (*p1 + 'A' - 'a');
|
||
else
|
||
putchar (*p1);
|
||
}
|
||
}
|
||
|
||
char *
|
||
xmalloc (size)
|
||
unsigned size;
|
||
{
|
||
register char *val = (char *) malloc (size);
|
||
|
||
if (val == 0)
|
||
fatal ("virtual memory exhausted");
|
||
return val;
|
||
}
|
||
|
||
char *
|
||
xrealloc (ptr, size)
|
||
char *ptr;
|
||
unsigned size;
|
||
{
|
||
char *result = (char *) realloc (ptr, size);
|
||
if (!result)
|
||
fatal ("virtual memory exhausted");
|
||
return result;
|
||
}
|
||
|
||
static void
|
||
fatal (s, a1, a2)
|
||
char *s;
|
||
{
|
||
fprintf (stderr, "genpeep: ");
|
||
fprintf (stderr, s, a1, a2);
|
||
fprintf (stderr, "\n");
|
||
exit (FATAL_EXIT_CODE);
|
||
}
|
||
|
||
/* More 'friendly' abort that prints the line and file.
|
||
config.h can #define abort fancy_abort if you like that sort of thing. */
|
||
|
||
void
|
||
fancy_abort ()
|
||
{
|
||
fatal ("Internal gcc abort.");
|
||
}
|
||
|
||
int
|
||
main (argc, argv)
|
||
int argc;
|
||
char **argv;
|
||
{
|
||
rtx desc;
|
||
FILE *infile;
|
||
extern rtx read_rtx ();
|
||
register int c;
|
||
|
||
max_opno = -1;
|
||
|
||
obstack_init (rtl_obstack);
|
||
|
||
if (argc <= 1)
|
||
fatal ("No input file name.");
|
||
|
||
infile = fopen (argv[1], "r");
|
||
if (infile == 0)
|
||
{
|
||
perror (argv[1]);
|
||
exit (FATAL_EXIT_CODE);
|
||
}
|
||
|
||
init_rtl ();
|
||
|
||
printf ("/* Generated automatically by the program `genpeep'\n\
|
||
from the machine description file `md'. */\n\n");
|
||
|
||
printf ("#include \"config.h\"\n");
|
||
printf ("#include \"rtl.h\"\n");
|
||
printf ("#include \"regs.h\"\n");
|
||
printf ("#include \"output.h\"\n");
|
||
printf ("#include \"real.h\"\n\n");
|
||
|
||
printf ("extern rtx peep_operand[];\n\n");
|
||
printf ("#define operands peep_operand\n\n");
|
||
|
||
printf ("rtx\npeephole (ins1)\n rtx ins1;\n{\n");
|
||
printf (" rtx insn, x, pat;\n");
|
||
printf (" int i;\n\n");
|
||
|
||
/* Early out: no peepholes for insns followed by barriers. */
|
||
printf (" if (NEXT_INSN (ins1)\n");
|
||
printf (" && GET_CODE (NEXT_INSN (ins1)) == BARRIER)\n");
|
||
printf (" return 0;\n\n");
|
||
|
||
/* Read the machine description. */
|
||
|
||
while (1)
|
||
{
|
||
c = read_skip_spaces (infile);
|
||
if (c == EOF)
|
||
break;
|
||
ungetc (c, infile);
|
||
|
||
desc = read_rtx (infile);
|
||
if (GET_CODE (desc) == DEFINE_PEEPHOLE)
|
||
{
|
||
gen_peephole (desc);
|
||
insn_code_number++;
|
||
}
|
||
if (GET_CODE (desc) == DEFINE_INSN
|
||
|| GET_CODE (desc) == DEFINE_EXPAND
|
||
|| GET_CODE (desc) == DEFINE_SPLIT)
|
||
{
|
||
insn_code_number++;
|
||
}
|
||
}
|
||
|
||
printf (" return 0;\n}\n\n");
|
||
|
||
if (max_opno == -1)
|
||
max_opno = 1;
|
||
|
||
printf ("rtx peep_operand[%d];\n", max_opno + 1);
|
||
|
||
fflush (stdout);
|
||
exit (ferror (stdout) != 0 ? FATAL_EXIT_CODE : SUCCESS_EXIT_CODE);
|
||
/* NOTREACHED */
|
||
return 0;
|
||
}
|