Michael Matz <matzmich@cs.tu-berlin.de>

        * flow.c (compute_flow_dominators): Process blocks FIFO not LIFO.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@32982 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 6cc9587..09ff60b 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,4 +1,8 @@
-2000-04-05  Alex Samuel  <samuel@codesourcery.com>
+2000-04-06  Michael Matz  <matzmich@cs.tu-berlin.de>
+
+       * flow.c (compute_flow_dominators): Process blocks FIFO not LIFO.
+
+2000-04-06  Alex Samuel  <samuel@codesourcery.com>
 
        * rtl.h (INSN_P): New macro.
        (successor_phi_fn): New typedef.

diff --git a/gcc/flow.c b/gcc/flow.c
index 4fd65dc..1f32fe1 100644 (file)
--- a/gcc/flow.c
+++ b/gcc/flow.c
@@ -5252,13 +5252,14 @@ compute_flow_dominators (dominators, post_dominators)
   int bb;
   sbitmap *temp_bitmap;
   edge e;
-  basic_block *worklist, *tos;
+  basic_block *worklist, *workend, *qin, *qout;
+  int qlen;
 
   /* Allocate a worklist array/queue.  Entries are only added to the
      list if they were not already on the list.  So the size is
      bounded by the number of basic blocks.  */
-  tos = worklist = (basic_block *) xmalloc (sizeof (basic_block)
-                   * n_basic_blocks);
+  worklist = (basic_block *) xmalloc (sizeof (basic_block) * n_basic_blocks);
+  workend = &worklist[n_basic_blocks];
 
   temp_bitmap = sbitmap_vector_alloc (n_basic_blocks, n_basic_blocks);
   sbitmap_vector_zero (temp_bitmap, n_basic_blocks);
@@ -5267,11 +5268,14 @@ compute_flow_dominators (dominators, post_dominators)
     {
       /* The optimistic setting of dominators requires us to put every
         block on the work list initially.  */
+      qin = qout = worklist;
       for (bb = 0; bb < n_basic_blocks; bb++)
        {
-         *tos++ = BASIC_BLOCK (bb);
+         *qin++ = BASIC_BLOCK (bb);
          BASIC_BLOCK (bb)->aux = BASIC_BLOCK (bb);
        }
+      qlen = n_basic_blocks;
+      qin = worklist;
 
       /* We want a maximal solution, so initially assume everything dominates
         everything else.  */
@@ -5282,10 +5286,14 @@ compute_flow_dominators (dominators, post_dominators)
        e->dest->aux = ENTRY_BLOCK_PTR;
 
       /* Iterate until the worklist is empty.  */
-      while (tos != worklist)
+      while (qlen)
        {
          /* Take the first entry off the worklist.  */
-         basic_block b = *--tos;
+         basic_block b = *qout++;
+         if (qout >= workend)
+           qout = worklist;
+         qlen--;
+
          bb = b->index;
 
          /* Compute the intersection of the dominators of all the
@@ -5325,7 +5333,11 @@ compute_flow_dominators (dominators, post_dominators)
                {
                  if (!e->dest->aux && e->dest != EXIT_BLOCK_PTR)
                    {
-                     *tos++ = e->dest;
+                     *qin++ = e->dest;
+                     if (qin >= workend)
+                       qin = worklist;
+                     qlen++;
+
                      e->dest->aux = e;
                    }
                }
@@ -5337,11 +5349,14 @@ compute_flow_dominators (dominators, post_dominators)
     {
       /* The optimistic setting of dominators requires us to put every
         block on the work list initially.  */
+      qin = qout = worklist;
       for (bb = 0; bb < n_basic_blocks; bb++)
        {
-         *tos++ = BASIC_BLOCK (bb);
+         *qin++ = BASIC_BLOCK (bb);
          BASIC_BLOCK (bb)->aux = BASIC_BLOCK (bb);
        }
+      qlen = n_basic_blocks;
+      qin = worklist;
 
       /* We want a maximal solution, so initially assume everything post
         dominates everything else.  */
@@ -5352,10 +5367,14 @@ compute_flow_dominators (dominators, post_dominators)
        e->src->aux = EXIT_BLOCK_PTR;
 
       /* Iterate until the worklist is empty.  */
-      while (tos != worklist)
+      while (qlen)
        {
          /* Take the first entry off the worklist.  */
-         basic_block b = *--tos;
+         basic_block b = *qout++;
+         if (qout >= workend)
+           qout = worklist;
+         qlen--;
+
          bb = b->index;
 
          /* Compute the intersection of the post dominators of all the
@@ -5398,13 +5417,18 @@ compute_flow_dominators (dominators, post_dominators)
                {
                  if (!e->src->aux && e->src != ENTRY_BLOCK_PTR)
                    {
-                     *tos++ = e->src;
+                     *qin++ = e->src;
+                     if (qin >= workend)
+                       qin = worklist;
+                     qlen++;
+
                      e->src->aux = e;
                    }
                }
            }
        }
     }
+
   free (temp_bitmap);
 }