[patch 6/9] genautomata chainsaw pass 1

Zack Weinberg zackw@panix.com
Sat Jan 7 06:39:00 GMT 2006


Okay, this is entirely tangential cleanups in genautomata and the code
it generates.  MAX_DFA_ISSUE_RATE is used nowhere, so kill it; so
there is no point in emitting a dead_lock_vect full of zeroes for
automata that have none (which is the normal case).  Also,
length_unit_log and max_insn_queue_index are never modified, so make
them const.

zw

	* genautomata.c (process_state_longest_path, max_dfa_issue_rate)
	(output_dfa_max_issue_rate, locked_states_num): Delete.
	(struct automaton): Add locked_states field.
	(output_dead_lock_vect): Save number of locked states in
	automaton->locked_states.  If it is zero, don't print anything.
	(output_max_insn_queue_index_def): Define max_insn_queue_index const.
	(output_internal_dead_lock_func): Only test the dead_lock_vect
	for automata that have locked states.
	(output_statistics): Always print the number of locked states for
	each automaton.  Calculate total number of locked states here.
	(write_automata): Don't call output_dfa_max_issue_rate.
	* genattrtab.c: Define length_unit_log as a const variable.
	* genattr.c: Don't emit MAX_DFA_ISSUE_RATE.  Declare
	max_insn_queue_index const.
	* final.c (length_unit_log): Declare const.
	* doc/tm.texi: Remove all references to MAX_DFA_ISSUE_RATE.

==================================================================
--- doc/tm.texi	(revision 108720)
+++ doc/tm.texi	(revision 108721)
@@ -5581,9 +5581,6 @@
 This value must be constant over the entire compilation.  If you need
 it to vary depending on what the instructions are, you must use
 @samp{TARGET_SCHED_VARIABLE_ISSUE}.
-You could define this hook to return the value of the macro
-@code{MAX_DFA_ISSUE_RATE}.
 @end deftypefn
 
 @deftypefn {Target Hook} int TARGET_SCHED_VARIABLE_ISSUE (FILE *@var{file}, int @var{verbose}, rtx @var{insn}, int @var{more})
@@ -5793,17 +5790,6 @@
 not in cases of "costly dependences", which this hooks allows to define.
 @end deftypefn
 
-Macros in the following table are generated by the program
-@file{genattr} and can be useful for writing the hooks.
-@defmac MAX_DFA_ISSUE_RATE
-The macro definition is generated in the automaton based pipeline
-description interface.  Its value is calculated from the automaton
-based pipeline description and is equal to maximal number of all insns
-described in constructions @samp{define_insn_reservation} which can be
-issued on the same processor cycle.
-@end defmac
 @node Sections
 @section Dividing the Output into Sections (Texts, Data, @dots{})
 @c the above section title is WAY too long.  maybe cut the part between
==================================================================
--- final.c	(revision 108720)
+++ final.c	(revision 108721)
@@ -144,7 +144,7 @@
 /* Whether to force emission of a line note before the next insn.  */
 static bool force_source_line = false;
   
-extern int length_unit_log; /* This is defined in insn-attrtab.c.  */
+extern const int length_unit_log; /* This is defined in insn-attrtab.c.  */
 
 /* Nonzero while outputting an `asm' with operands.
    This means that inconsistencies are the user's fault, so don't die.
==================================================================
--- genautomata.c	(revision 108720)
+++ genautomata.c	(revision 108721)
@@ -414,8 +414,6 @@
 
 static void output_range_type            (FILE *, long int, long int);
 static int longest_path_length           (state_t);
-static void process_state_longest_path_length (state_t);
-static void output_dfa_max_issue_rate    (void);
 static void output_chip_member_name      (FILE *, automaton_t);
 static void output_temp_chip_member_name (FILE *, automaton_t);
 static void output_translate_vect_name   (FILE *, automaton_t);
@@ -1155,6 +1153,8 @@
      8) elements in one vector element.  So the compression factor can
      be 1 (no compression), 2, 4, 8.  */
   int min_issue_delay_table_compression_factor;
+  /* Total number of locked states in this automaton.  */
+  int locked_states;
 };
 
 /* The following is the element of the list of automata.  */
@@ -7015,47 +7015,6 @@
   return result;
 }
 
-/* The following variable value is value of the corresponding global
-   variable in the automaton based pipeline interface.  */
-static int max_dfa_issue_rate;
-/* The following function processes the longest path length staring
-   from STATE to find MAX_DFA_ISSUE_RATE.  */
-static void
-process_state_longest_path_length (state_t state)
-{
-  int value;
-  value = longest_path_length (state);
-  if (value > max_dfa_issue_rate)
-    max_dfa_issue_rate = value;
-}
-/* The following macro value is name of the corresponding global
-   variable in the automaton based pipeline interface.  */
-#define MAX_DFA_ISSUE_RATE_VAR_NAME "max_dfa_issue_rate"
-/* The following function calculates value of the corresponding
-   global variable and outputs its declaration.  */
-static void
-output_dfa_max_issue_rate (void)
-{
-  automaton_t automaton;
-  gcc_assert (UNDEFINED_LONGEST_PATH_LENGTH != ON_THE_PATH && ON_THE_PATH < 0);
-  max_dfa_issue_rate = 0;
-  for (automaton = description->first_automaton;
-       automaton != NULL;
-       automaton = automaton->next_automaton)
-    pass_states (automaton, process_state_longest_path_length);
-  fprintf (output_file, "\nint %s = %d;\n",
-	   MAX_DFA_ISSUE_RATE_VAR_NAME, max_dfa_issue_rate);
-}
 /* The function outputs all initialization values of VECT.  */
 static void
 output_vect (vla_hwint_t vect)
@@ -7977,12 +7936,6 @@
   VEC_free (vect_el_t,heap, compressed_min_issue_delay_vect);
 }
 
-#ifndef NDEBUG
-/* Number of states which contains transition only by advancing cpu
-   cycle.  */
-static int locked_states_num;
-#endif
 /* Form and output vector representing the locked states of
    AUTOMATON.  */
 static void
@@ -7995,6 +7948,7 @@
   /* Create vect of pointers to states ordered by num of
      transitions from the state (state with the maximum num is the
      first).  */
+  automaton->locked_states = 0;
   output_states_vect = 0;
   pass_states (automaton, add_states_vect_el);
 
@@ -8005,16 +7959,19 @@
       state_t s = VEC_index (state_t, output_states_vect, i);
       arc = first_out_arc (s);
       gcc_assert (arc);
-      VEC_replace (vect_el_t, dead_lock_vect, s->order_state_num,
-		   (next_out_arc (arc) == NULL
-		    && (arc->insn->insn_reserv_decl
-			== DECL_INSN_RESERV (advance_cycle_insn_decl))
-		    ? 1 : 0));
-#ifndef NDEBUG
-      if (VEC_index (vect_el_t,dead_lock_vect, s->order_state_num))
-        locked_states_num++;
-#endif
+      if (next_out_arc (arc) == NULL
+	  && (arc->insn->insn_reserv_decl
+	      == DECL_INSN_RESERV (advance_cycle_insn_decl)))
+	{
+	  VEC_replace (vect_el_t, dead_lock_vect, s->order_state_num, 1);
+	  automaton->locked_states++;
+	}
+      else
+	VEC_replace (vect_el_t, dead_lock_vect, s->order_state_num, 0);
     }
+  if (automaton->locked_states == 0)
+    return;
+
   fprintf (output_file, "/* Vector for locked state flags.  */\n");
   fprintf (output_file, "static const ");
   output_range_type (output_file, 0, 1);
@@ -8085,9 +8042,6 @@
 {
   automaton_t automaton;
 
-#ifndef NDEBUG
-  locked_states_num = 0;
-#endif
   initiate_min_issue_delay_pass_states ();
   for (automaton = description->first_automaton;
        automaton != NULL;
@@ -8139,10 +8093,10 @@
   for (i = 0; (1 << i) <= max; i++)
     ;
   gcc_assert (i >= 0);
-  fprintf (output_file, "\nint max_insn_queue_index = %d;\n\n", (1 << i) - 1);
+  fprintf (output_file, "\nconst int max_insn_queue_index = %d;\n\n",
+	   (1 << i) - 1);
 }
 
 /* The function outputs switch cases for insn reservations using
    function *output_automata_list_code.  */
 static void
@@ -8575,19 +8529,20 @@
 {
   automaton_t automaton;
 
-  fprintf (output_file, "static int\n%s (struct %s *%s)\n",
+  fprintf (output_file, "static int\n%s (struct %s *ARG_UNUSED (%s))\n",
 	   INTERNAL_DEAD_LOCK_FUNC_NAME, CHIP_NAME, CHIP_PARAMETER_NAME);
   fprintf (output_file, "{\n");
   for (automaton = description->first_automaton;
        automaton != NULL;
        automaton = automaton->next_automaton)
-    {
-      fprintf (output_file, "  if (");
-      output_dead_lock_vect_name (output_file, automaton);
-      fprintf (output_file, " [%s->", CHIP_PARAMETER_NAME);
-      output_chip_member_name (output_file, automaton);
-      fprintf (output_file, "])\n    return 1/* TRUE */;\n");
-    }
+    if (automaton->locked_states)
+      {
+	fprintf (output_file, "  if (");
+	output_dead_lock_vect_name (output_file, automaton);
+	fprintf (output_file, " [%s->", CHIP_PARAMETER_NAME);
+	output_chip_member_name (output_file, automaton);
+	fprintf (output_file, "])\n    return 1/* TRUE */;\n");
+      }
   fprintf (output_file, "  return 0/* FALSE */;\n}\n\n");
 }
 
@@ -9314,6 +9269,7 @@
   int state_alts_comb_vect_els = 0;
   int state_alts_full_vect_els = 0;
   int min_issue_delay_vect_els = 0;
+  int locked_states = 0;
 #endif
 
   for (automaton = description->first_automaton;
@@ -9336,6 +9292,7 @@
 	}
       fprintf (f, "    %5d all insns      %5d insn equivalence classes\n",
 	       description->insns_num, automaton->insn_equiv_classes_num);
+      fprintf (f, "    %d locked states\n", automaton->locked_states);
 #ifndef NDEBUG
       fprintf
 	(f, "%5ld transition comb vector els, %5ld trans table els: %s\n",
@@ -9363,6 +9320,8 @@
         += VEC_length (vect_el_t, automaton->state_alts_table->full_vect);
       min_issue_delay_vect_els
 	+= states_num * automaton->insn_equiv_classes_num;
+      locked_states
+	+= automaton->locked_states;
 #endif
     }
 #ifndef NDEBUG
@@ -9376,7 +9335,7 @@
     (f, "%5d all state alts comb vector els, %5d all state alts table els\n",
      state_alts_comb_vect_els, state_alts_full_vect_els);
   fprintf (f, "%5d all min delay table els\n", min_issue_delay_vect_els);
-  fprintf (f, "%5d locked states num\n", locked_states_num);
+  fprintf (f, "%5d all locked states\n", locked_states);
 #endif
 }
 
@@ -9865,7 +9824,6 @@
   output_time = create_ticker ();
   if (progress_flag)
     fprintf (stderr, "Forming and outputting automata tables...");
-  output_dfa_max_issue_rate ();
   output_tables ();
   if (progress_flag)
     {
==================================================================
--- genattrtab.c	(revision 108720)
+++ genattrtab.c	(revision 108721)
@@ -1690,7 +1690,7 @@
       for (length_unit_log = 0; length_or & 1; length_or >>= 1)
 	length_unit_log++;
     }
-  printf ("int length_unit_log = %u;\n", length_unit_log);
+  printf ("const int length_unit_log = %u;\n", length_unit_log);
 }
 
 /* Take a COND expression and see if any of the conditions in it can be
==================================================================
--- genattr.c	(revision 108720)
+++ genattr.c	(revision 108721)
@@ -174,13 +174,6 @@
       printf ("#define CPU_UNITS_QUERY 0\n");
       printf ("#endif\n\n");
       /* Interface itself: */
-      printf ("extern int max_dfa_issue_rate;\n\n");
-      printf ("/* The following macro value is calculated from the\n");
-      printf ("   automaton based pipeline description and is equal to\n");
-      printf ("   maximal number of all insns described in constructions\n");
-      printf ("   `define_insn_reservation' which can be issued on the\n");
-      printf ("   same processor cycle. */\n");
-      printf ("#define MAX_DFA_ISSUE_RATE max_dfa_issue_rate\n\n");
       printf ("/* Insn latency time defined in define_insn_reservation. */\n");
       printf ("extern int insn_default_latency (rtx);\n\n");
       printf ("/* Return nonzero if there is a bypass for given insn\n");
@@ -198,7 +191,7 @@
       printf ("#endif\n\n");
       printf ("/* Maximal possible number of insns waiting results being\n");
       printf ("   produced by insns whose execution is not finished. */\n");
-      printf ("extern int max_insn_queue_index;\n\n");
+      printf ("extern const int max_insn_queue_index;\n\n");
       printf ("/* Pointer to data describing current state of DFA.  */\n");
       printf ("typedef void *state_t;\n\n");
       printf ("/* Size of the data in bytes.  */\n");



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