[PATCH] Improve PR91257, specialize bitmap_ior_and_compl_into

[Richard Biener]

bitmap_ior_and_compl_into is currently doing bitmap_and_compl into
a temporary bitmap and then bitmap_ior_into.  The following uses
the existing implementation of bitmap_ior_and_into and exchanges
the core worker based on a template parameter.

This results in a slight savings in out-of-SSA time (it also avoids
using the default obstack for the temporary while all operands for
out-of-SSA and the result live in different obstacks).

Bootstrap and regtest running on x86_64-unknown-linux-gnu.

Richard.

2019-07-30  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/91257
	* bitmap.c (bitmap_ior_and_maybe_compl): New templated function
	based on bitmap_ior_and_into.
	(bitmap_ior_and_into): Wrap around bitmap_ior_and_maybe_compl.
	(bitmap_ior_and_compl_into): Likewise.

Index: gcc/bitmap.c
===================================================================
--- gcc/bitmap.c	(revision 273795)
+++ gcc/bitmap.c	(working copy)
@@ -2345,28 +2399,11 @@ bitmap_ior_and_compl (bitmap dst, const_
   return changed;
 }
 
-/* A |= (B & ~C).  Return true if A changes.  */
+/* Helper for A |= (B & ~C) and A |= (B & C).  Return true if A changes.  */
 
-bool
-bitmap_ior_and_compl_into (bitmap a, const_bitmap b, const_bitmap c)
-{
-  bitmap_head tmp;
-  bool changed;
-
-  gcc_checking_assert (!a->tree_form && !b->tree_form && !c->tree_form);
-
-  bitmap_initialize (&tmp, &bitmap_default_obstack);
-  bitmap_and_compl (&tmp, b, c);
-  changed = bitmap_ior_into (a, &tmp);
-  bitmap_clear (&tmp);
-
-  return changed;
-}
-
-/* A |= (B & C).  Return true if A changes.  */
-
-bool
-bitmap_ior_and_into (bitmap a, const_bitmap b, const_bitmap c)
+template <bool compl_p>
+static bool
+bitmap_ior_and_maybe_compl_into (bitmap a, const_bitmap b, const_bitmap c)
 {
   bitmap_element *a_elt = a->first;
   const bitmap_element *b_elt = b->first;
@@ -2408,11 +2445,18 @@ bitmap_ior_and_into (bitmap a, const_bit
 
       overall = 0;
       and_elt.indx = b_elt->indx;
-      for (ix = 0; ix < BITMAP_ELEMENT_WORDS; ix++)
-	{
-	  and_elt.bits[ix] = b_elt->bits[ix] & c_elt->bits[ix];
-	  overall |= and_elt.bits[ix];
-	}
+      if (compl_p)
+	for (ix = 0; ix < BITMAP_ELEMENT_WORDS; ix++)
+	  {
+	    and_elt.bits[ix] = b_elt->bits[ix] & ~c_elt->bits[ix];
+	    overall |= and_elt.bits[ix];
+	  }
+      else
+	for (ix = 0; ix < BITMAP_ELEMENT_WORDS; ix++)
+	  {
+	    and_elt.bits[ix] = b_elt->bits[ix] & c_elt->bits[ix];
+	    overall |= and_elt.bits[ix];
+	  }
 
       b_elt = b_elt->next;
       c_elt = c_elt->next;
@@ -2444,6 +2488,22 @@ bitmap_ior_and_into (bitmap a, const_bit
   return changed;
 }
 
+/* A |= (B & ~C).  Return true if A changes.  */
+
+bool
+bitmap_ior_and_compl_into (bitmap a, const_bitmap b, const_bitmap c)
+{
+  return bitmap_ior_and_maybe_compl_into<true> (a, b, c);
+}
+
+/* A |= (B & C).  Return true if A changes.  */
+
+bool
+bitmap_ior_and_into (bitmap a, const_bitmap b, const_bitmap c)
+{
+  return bitmap_ior_and_maybe_compl_into<false> (a, b, c);
+}
+
 /* Compute hash of bitmap (for purposes of hashing).  */
 
 hashval_t