Revert "Basic block renumbering removal", and two followup patches.

From-SVN: r53537

1 files changed, 64 insertions, 62 deletions

diff --git a/gcc/cfgbuild.c b/gcc/cfgbuild.c
index d531877..5ce9d40 100644
--- a/gcc/cfgbuild.c
+++ b/gcc/cfgbuild.c
@@ -50,8 +50,7 @@ Software Foundation, 59 Temple Place - Suite 330, Boston, MA
 static int count_basic_blocks		PARAMS ((rtx));
 static void find_basic_blocks_1		PARAMS ((rtx));
 static rtx find_label_refs		PARAMS ((rtx, rtx));
-static void make_edges			PARAMS ((rtx, basic_block,
-						 basic_block, int));
+static void make_edges			PARAMS ((rtx, int, int, int));
 static void make_label_edge		PARAMS ((sbitmap *, basic_block,
 						 rtx, int));
 static void make_eh_edge		PARAMS ((sbitmap *, basic_block, rtx));
@@ -281,10 +280,9 @@ make_eh_edge (edge_cache, src, insn)
 static void
 make_edges (label_value_list, min, max, update_p)
      rtx label_value_list;
-     basic_block min, max;
-     int update_p;
+     int min, max, update_p;
 {
-  basic_block bb;
+  int i;
   sbitmap *edge_cache = NULL;
 
   /* Assume no computed jump; revise as we create edges.  */
@@ -295,26 +293,28 @@ make_edges (label_value_list, min, max, update_p)
      amount of time searching the edge lists for duplicates.  */
   if (forced_labels || label_value_list)
     {
-      edge_cache = sbitmap_vector_alloc (last_basic_block, last_basic_block);
-      sbitmap_vector_zero (edge_cache, last_basic_block);
+      edge_cache = sbitmap_vector_alloc (n_basic_blocks, n_basic_blocks);
+      sbitmap_vector_zero (edge_cache, n_basic_blocks);
 
       if (update_p)
-        FOR_BB_BETWEEN (bb, min, max->next_bb, next_bb)
+	for (i = min; i <= max; ++i)
 	  {
 	    edge e;
 
-	    for (e = bb->succ; e ; e = e->succ_next)
+	    for (e = BASIC_BLOCK (i)->succ; e ; e = e->succ_next)
 	      if (e->dest != EXIT_BLOCK_PTR)
-	        SET_BIT (edge_cache[bb->sindex], e->dest->sindex);
+	        SET_BIT (edge_cache[i], e->dest->index);
 	  }
     }
 
-  if (min == ENTRY_BLOCK_PTR->next_bb)
-    cached_make_edge (edge_cache, ENTRY_BLOCK_PTR, min,
+  /* By nature of the way these get numbered, block 0 is always the entry.  */
+  if (min == 0)
+    cached_make_edge (edge_cache, ENTRY_BLOCK_PTR, BASIC_BLOCK (0),
 		      EDGE_FALLTHRU);
 
-  FOR_BB_BETWEEN (bb, min, max->next_bb, next_bb)
+  for (i = min; i <= max; ++i)
     {
+      basic_block bb = BASIC_BLOCK (i);
       rtx insn, x;
       enum rtx_code code;
       int force_fallthru = 0;
@@ -443,16 +443,15 @@ make_edges (label_value_list, min, max, update_p)
 
       /* Find out if we can drop through to the next block.  */
       insn = next_nonnote_insn (insn);
-
-      if (!insn || (bb->next_bb == EXIT_BLOCK_PTR && force_fallthru))
+      if (!insn || (i + 1 == n_basic_blocks && force_fallthru))
 	cached_make_edge (edge_cache, bb, EXIT_BLOCK_PTR, EDGE_FALLTHRU);
-      else if (bb->next_bb != EXIT_BLOCK_PTR)
+      else if (i + 1 < n_basic_blocks)
 	{
-	  rtx tmp = bb->next_bb->head;
+	  rtx tmp = BLOCK_HEAD (i + 1);
 	  if (GET_CODE (tmp) == NOTE)
 	    tmp = next_nonnote_insn (tmp);
 	  if (force_fallthru || insn == tmp)
-	    cached_make_edge (edge_cache, bb, bb->next_bb,
+	    cached_make_edge (edge_cache, bb, BASIC_BLOCK (i + 1),
 			      EDGE_FALLTHRU);
 	}
     }
@@ -471,12 +470,12 @@ find_basic_blocks_1 (f)
      rtx f;
 {
   rtx insn, next;
+  int i = 0;
   rtx bb_note = NULL_RTX;
   rtx lvl = NULL_RTX;
   rtx trll = NULL_RTX;
   rtx head = NULL_RTX;
   rtx end = NULL_RTX;
-  basic_block prev = ENTRY_BLOCK_PTR;
 
   /* We process the instructions in a slightly different way than we did
      previously.  This is so that we see a NOTE_BASIC_BLOCK after we have
@@ -493,7 +492,7 @@ find_basic_blocks_1 (f)
       if ((GET_CODE (insn) == CODE_LABEL || GET_CODE (insn) == BARRIER)
 	  && head)
 	{
-	  prev = create_basic_block_structure (last_basic_block++, head, end, bb_note, prev);
+	  create_basic_block_structure (i++, head, end, bb_note);
 	  head = end = NULL_RTX;
 	  bb_note = NULL_RTX;
 	}
@@ -507,7 +506,7 @@ find_basic_blocks_1 (f)
 
       if (head && control_flow_insn_p (insn))
 	{
-	  prev = create_basic_block_structure (last_basic_block++, head, end, bb_note, prev);
+	  create_basic_block_structure (i++, head, end, bb_note);
 	  head = end = NULL_RTX;
 	  bb_note = NULL_RTX;
 	}
@@ -589,11 +588,11 @@ find_basic_blocks_1 (f)
     }
 
   if (head != NULL_RTX)
-    create_basic_block_structure (last_basic_block++, head, end, bb_note, prev);
+    create_basic_block_structure (i++, head, end, bb_note);
   else if (bb_note)
     delete_insn (bb_note);
 
-  if (last_basic_block != num_basic_blocks)
+  if (i != n_basic_blocks)
     abort ();
 
   label_value_list = lvl;
@@ -613,7 +612,6 @@ find_basic_blocks (f, nregs, file)
      FILE *file ATTRIBUTE_UNUSED;
 {
   int max_uid;
-  basic_block bb;
   timevar_push (TV_CFG);
 
   basic_block_for_insn = 0;
@@ -621,21 +619,20 @@ find_basic_blocks (f, nregs, file)
   /* Flush out existing data.  */
   if (basic_block_info != NULL)
     {
+      int i;
+
       clear_edges ();
 
       /* Clear bb->aux on all extant basic blocks.  We'll use this as a
 	 tag for reuse during create_basic_block, just in case some pass
 	 copies around basic block notes improperly.  */
-      FOR_ALL_BB (bb)
- 	bb->aux = NULL;
+      for (i = 0; i < n_basic_blocks; ++i)
+	BASIC_BLOCK (i)->aux = NULL;
 
       VARRAY_FREE (basic_block_info);
     }
 
-  num_basic_blocks = count_basic_blocks (f);
-  last_basic_block = 0;
-  ENTRY_BLOCK_PTR->next_bb = EXIT_BLOCK_PTR;
-  EXIT_BLOCK_PTR->prev_bb = ENTRY_BLOCK_PTR;
+  n_basic_blocks = count_basic_blocks (f);
 
   /* Size the basic block table.  The actual structures will be allocated
      by find_basic_blocks_1, since we want to keep the structure pointers
@@ -645,7 +642,7 @@ find_basic_blocks (f, nregs, file)
      instructions at all until close to the end of compilation when we
      actually lay them out.  */
 
-  VARRAY_BB_INIT (basic_block_info, num_basic_blocks, "basic_block_info");
+  VARRAY_BB_INIT (basic_block_info, n_basic_blocks, "basic_block_info");
 
   find_basic_blocks_1 (f);
 
@@ -664,7 +661,7 @@ find_basic_blocks (f, nregs, file)
   compute_bb_for_insn (max_uid);
 
   /* Discover the edges of our cfg.  */
-  make_edges (label_value_list, ENTRY_BLOCK_PTR->next_bb, EXIT_BLOCK_PTR->prev_bb, 0);
+  make_edges (label_value_list, 0, n_basic_blocks - 1, 0);
 
   /* Do very simple cleanup now, for the benefit of code that runs between
      here and cleanup_cfg, e.g. thread_prologue_and_epilogue_insns.  */
@@ -793,24 +790,25 @@ void
 find_many_sub_basic_blocks (blocks)
      sbitmap blocks;
 {
-  basic_block bb, min, max;
+  int i;
+  int min, max;
 
-  FOR_ALL_BB (bb)
-    SET_STATE (bb,
-	       TEST_BIT (blocks, bb->sindex) ? BLOCK_TO_SPLIT : BLOCK_ORIGINAL);
+  for (i = 0; i < n_basic_blocks; i++)
+    SET_STATE (BASIC_BLOCK (i),
+	       TEST_BIT (blocks, i) ? BLOCK_TO_SPLIT : BLOCK_ORIGINAL);
 
-  FOR_ALL_BB (bb)
-    if (STATE (bb) == BLOCK_TO_SPLIT)
-      find_bb_boundaries (bb);
+  for (i = 0; i < n_basic_blocks; i++)
+    if (STATE (BASIC_BLOCK (i)) == BLOCK_TO_SPLIT)
+      find_bb_boundaries (BASIC_BLOCK (i));
 
-  FOR_ALL_BB (bb)
-    if (STATE (bb) != BLOCK_ORIGINAL)
+  for (i = 0; i < n_basic_blocks; i++)
+    if (STATE (BASIC_BLOCK (i)) != BLOCK_ORIGINAL)
       break;
 
-  min = max = bb;
-  for (; bb != EXIT_BLOCK_PTR; bb = bb->next_bb)
-    if (STATE (bb) != BLOCK_ORIGINAL)
-      max = bb;
+  min = max = i;
+  for (; i < n_basic_blocks; i++)
+    if (STATE (BASIC_BLOCK (i)) != BLOCK_ORIGINAL)
+      max = i;
 
   /* Now re-scan and wire in all edges.  This expect simple (conditional)
      jumps at the end of each new basic blocks.  */
@@ -818,28 +816,29 @@ find_many_sub_basic_blocks (blocks)
 
   /* Update branch probabilities.  Expect only (un)conditional jumps
      to be created with only the forward edges.  */
-  FOR_BB_BETWEEN (bb, min, max->next_bb, next_bb)
+  for (i = min; i <= max; i++)
     {
       edge e;
+      basic_block b = BASIC_BLOCK (i);
 
-      if (STATE (bb) == BLOCK_ORIGINAL)
+      if (STATE (b) == BLOCK_ORIGINAL)
 	continue;
-      if (STATE (bb) == BLOCK_NEW)
+      if (STATE (b) == BLOCK_NEW)
 	{
-	  bb->count = 0;
-	  bb->frequency = 0;
-	  for (e = bb->pred; e; e=e->pred_next)
+	  b->count = 0;
+	  b->frequency = 0;
+	  for (e = b->pred; e; e=e->pred_next)
 	    {
-	      bb->count += e->count;
-	      bb->frequency += EDGE_FREQUENCY (e);
+	      b->count += e->count;
+	      b->frequency += EDGE_FREQUENCY (e);
 	    }
 	}
 
-      compute_outgoing_frequencies (bb);
+      compute_outgoing_frequencies (b);
     }
 
-  FOR_ALL_BB (bb)
-    SET_STATE (bb, 0);
+  for (i = 0; i < n_basic_blocks; i++)
+    SET_STATE (BASIC_BLOCK (i), 0);
 }
 
 /* Like above but for single basic block only.  */
@@ -848,12 +847,14 @@ void
 find_sub_basic_blocks (bb)
     basic_block bb;
 {
-  basic_block min, max, b;
-  basic_block next = bb->next_bb;
+  int i;
+  int min, max;
+  basic_block next = (bb->index == n_basic_blocks - 1
+		      ? NULL : BASIC_BLOCK (bb->index + 1));
 
-  min = bb;
+  min = bb->index;
   find_bb_boundaries (bb);
-  max = next->prev_bb;
+  max = (next ? next->index : n_basic_blocks) - 1;
 
   /* Now re-scan and wire in all edges.  This expect simple (conditional)
      jumps at the end of each new basic blocks.  */
@@ -861,11 +862,12 @@ find_sub_basic_blocks (bb)
 
   /* Update branch probabilities.  Expect only (un)conditional jumps
      to be created with only the forward edges.  */
-  FOR_BB_BETWEEN (b, min, max->next_bb, next_bb)
+  for (i = min; i <= max; i++)
     {
       edge e;
+      basic_block b = BASIC_BLOCK (i);
 
-      if (b != min)
+      if (i != min)
 	{
 	  b->count = 0;
 	  b->frequency = 0;