predict.c (block_info_def): Add nvisited.

	* predict.c (block_info_def): Add nvisited.
	(propagate_freq): Count nvisited; re-queue delayed blocks; handle
	irreducible regions.

	* flow.c (dump_edge_info): Dump the probability of edge.
	(combine_predictions_for_insn): Dump the basic block.

From-SVN: r43522

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 2f80724e815235bf69d8bc513030e4e97f2ad907..48cffe464051531a07310f26e76160615dc0777a 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,12 @@
+Sat Jun 23 01:16:42 CEST 2001  Jan Hubicka  <jh@suse.cz>
+
+       * predict.c (block_info_def): Add nvisited.
+       (propagate_freq): Count nvisited; re-queue delayed blocks; handle
+       irreducible regions.
+
+       * flow.c (dump_edge_info): Dump the probability of edge.
+       (combine_predictions_for_insn): Dump the basic block.
+
 2001-06-22  Joseph S. Myers  <jsm28@cam.ac.uk>
 
        * doc/gcc.texi: Update documentation of source files of C

diff --git a/gcc/flow.c b/gcc/flow.c
index 2d7ee8047d943b84b33d66a164968d3f725c4611..5c0c6d72ad40cae6b9e384a629d0146a7a34affe 100644 (file)
--- a/gcc/flow.c
+++ b/gcc/flow.c
@@ -6405,6 +6405,9 @@ dump_edge_info (file, e, do_succ)
   else
     fprintf (file, " %d", side->index);
 
+  if (e->probability)
+    fprintf (file, " [%.1f%%] ", e->probability * 100.0 / REG_BR_PROB_BASE);
+
   if (e->count)
     {
       fprintf (file, " count:");

diff --git a/gcc/predict.c b/gcc/predict.c
index 4b29e592093d716e6acabdfe2fe1c841b97eb2de..2bf13b3c537883fbbb591e92c9656f262c0e41bf 100644 (file)
--- a/gcc/predict.c
+++ b/gcc/predict.c
@@ -215,7 +215,8 @@ combine_predictions_for_insn (insn, bb)
   int best_predictor = END_PREDICTORS;
 
   if (rtl_dump_file)
-    fprintf (rtl_dump_file, "Predictions for insn %i\n", INSN_UID (insn));
+    fprintf (rtl_dump_file, "Predictions for insn %i bb %i\n", INSN_UID (insn),
+            bb->index);
 
   /* We implement "first match" heuristics and use probability guessed
      by predictor with smallest index.  In future we will use better
@@ -541,6 +542,10 @@ typedef struct block_info_def
 
   /* True if block already converted.  */
   int visited:1;
+
+  /* Number of block proceeded before adding basic block to the queue.  Used
+     to recognize irregular regions.  */
+  int nvisited;
 } *block_info;
 
 /* Similar information for edges.  */
@@ -567,6 +572,7 @@ propagate_freq (head)
   basic_block last = bb;
   edge e;
   basic_block nextbb;
+  int nvisited = 0;
 
   BLOCK_INFO (head)->frequency = 1;
   for (; bb; bb = nextbb)
@@ -581,12 +587,39 @@ propagate_freq (head)
        {
          for (e = bb->pred; e; e = e->pred_next)
            if (!BLOCK_INFO (e->src)->visited && !EDGE_INFO (e)->back_edge)
+             break;
+
+         /* We didn't proceeded all predecesors of edge e yet.  These may
+            be waiting in the queue or we may hit irreducible region.
+
+            To avoid infinite looping on irrecudible regions, count number
+            of block proceeded at the time basic block has been queued.  In the
+            case number didn't changed, we've hit irreducible region and we
+            forget the backward edge.  This can increase time complexity
+            by the number of irreducible blocks, but in same way standard the
+            loop does, so it should not result in noticeable slowodwn.
+
+            Alternativly we may distinquish backward and cross edges in the
+            DFS tree by preprocesing pass and ignore existence of non-loop
+            backward edges.  */
+         if (e && BLOCK_INFO (bb)->nvisited != nvisited)
+           {
+             if (!nextbb)
+               nextbb = e->dest;
+             else
+               BLOCK_INFO (last)->next = e->dest;
+             BLOCK_INFO (last)->nvisited = nvisited;
+             last = e->dest;
              continue;
+           }
+         else if (e && rtl_dump_file)
+           fprintf (rtl_dump_file, "Irreducible region hit, ignoring edge to bb %i\n",
+                    bb->index);
 
          for (e = bb->pred; e; e = e->pred_next)
            if (EDGE_INFO (e)->back_edge)
              cyclic_probability += EDGE_INFO (e)->back_edge_prob;
-           else
+           else if (BLOCK_INFO (e->src)->visited)
              frequency += (e->probability
                            * BLOCK_INFO (e->src)->frequency /
                            REG_BR_PROB_BASE);
@@ -616,8 +649,10 @@ propagate_freq (head)
              nextbb = e->dest;
            else
              BLOCK_INFO (last)->next = e->dest;
+           BLOCK_INFO (last)->nvisited = nvisited;
            last = e->dest;
          }
+      nvisited ++;
     }
 }