Initial revision

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@48 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 489 insertions, 0 deletions

diff --git a/gcc/genpeep.c b/gcc/genpeep.c
new file mode 100644
index 00000000000..832196f9055
--- /dev/null
+++ b/gcc/genpeep.c
@@ -0,0 +1,489 @@
+/* Generate code from machine description to perform peephole optimizations.
+   Copyright (C) 1987, 1989 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 = XVECLEN (x, i) - 1; j >= 0; 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;
+}