Split up value_range::intersect into base (value_range_base) and

derived versions (value_range).

From-SVN: r272058

1 files changed, 62 insertions, 31 deletions

diff --git a/gcc/tree-vrp.c b/gcc/tree-vrp.c
index fdda64c..d94de2b 100644
--- a/gcc/tree-vrp.c
+++ b/gcc/tree-vrp.c
@@ -6020,30 +6020,26 @@ intersect_ranges (enum value_range_kind *vr0type,
 }
 
 
-/* Intersect the two value-ranges *VR0 and *VR1 and store the result
-   in *VR0.  This may not be the smallest possible such range.  */
+/* Helper for the intersection operation for value ranges.  Given two
+   value ranges VR0 and VR1, return the intersection of the two
+   ranges.  This may not be the smallest possible such range.  */
 
-void
-value_range::intersect_helper (value_range *vr0, const value_range *vr1)
+value_range_base
+value_range_base::intersect_helper (const value_range_base *vr0,
+				    const value_range_base *vr1)
 {
   /* If either range is VR_VARYING the other one wins.  */
   if (vr1->varying_p ())
-    return;
+    return *vr0;
   if (vr0->varying_p ())
-    {
-      vr0->deep_copy (vr1);
-      return;
-    }
+    return *vr1;
 
   /* When either range is VR_UNDEFINED the resulting range is
      VR_UNDEFINED, too.  */
   if (vr0->undefined_p ())
-    return;
+    return *vr0;
   if (vr1->undefined_p ())
-    {
-      vr0->set_undefined ();
-      return;
-    }
+    return *vr1;
 
   value_range_kind vr0type = vr0->kind ();
   tree vr0min = vr0->min ();
@@ -6053,28 +6049,34 @@ value_range::intersect_helper (value_range *vr0, const value_range *vr1)
   /* Make sure to canonicalize the result though as the inversion of a
      VR_RANGE can still be a VR_RANGE.  Work on a temporary so we can
      fall back to vr0 when this turns things to varying.  */
-  value_range tem;
+  value_range_base tem;
   tem.set_and_canonicalize (vr0type, vr0min, vr0max);
   /* If that failed, use the saved original VR0.  */
   if (tem.varying_p ())
-    return;
-  vr0->update (tem.kind (), tem.min (), tem.max ());
+    return *vr0;
 
-  /* If the result is VR_UNDEFINED there is no need to mess with
-     the equivalencies.  */
-  if (vr0->undefined_p ())
-    return;
+  return tem;
+}
 
-  /* The resulting set of equivalences for range intersection is the union of
-     the two sets.  */
-  if (vr0->m_equiv && vr1->m_equiv && vr0->m_equiv != vr1->m_equiv)
-    bitmap_ior_into (vr0->m_equiv, vr1->m_equiv);
-  else if (vr1->m_equiv && !vr0->m_equiv)
+void
+value_range_base::intersect (const value_range_base *other)
+{
+  if (dump_file && (dump_flags & TDF_DETAILS))
     {
-      /* All equivalence bitmaps are allocated from the same obstack.  So
-	 we can use the obstack associated with VR to allocate vr0->equiv.  */
-      vr0->m_equiv = BITMAP_ALLOC (vr1->m_equiv->obstack);
-      bitmap_copy (m_equiv, vr1->m_equiv);
+      fprintf (dump_file, "Intersecting\n  ");
+      dump_value_range (dump_file, this);
+      fprintf (dump_file, "\nand\n  ");
+      dump_value_range (dump_file, other);
+      fprintf (dump_file, "\n");
+    }
+
+  *this = intersect_helper (this, other);
+
+  if (dump_file && (dump_flags & TDF_DETAILS))
+    {
+      fprintf (dump_file, "to\n  ");
+      dump_value_range (dump_file, this);
+      fprintf (dump_file, "\n");
     }
 }
 
@@ -6089,7 +6091,36 @@ value_range::intersect (const value_range *other)
       dump_value_range (dump_file, other);
       fprintf (dump_file, "\n");
     }
-  intersect_helper (this, other);
+
+  /* If THIS is varying we want to pick up equivalences from OTHER.
+     Just special-case this here rather than trying to fixup after the
+     fact.  */
+  if (this->varying_p ())
+    this->deep_copy (other);
+  else
+    {
+      value_range_base tem = intersect_helper (this, other);
+      this->update (tem.kind (), tem.min (), tem.max ());
+
+      /* If the result is VR_UNDEFINED there is no need to mess with
+	 equivalencies.  */
+      if (!undefined_p ())
+	{
+	  /* The resulting set of equivalences for range intersection
+	     is the union of the two sets.  */
+	  if (m_equiv && other->m_equiv && m_equiv != other->m_equiv)
+	    bitmap_ior_into (m_equiv, other->m_equiv);
+	  else if (other->m_equiv && !m_equiv)
+	    {
+	      /* All equivalence bitmaps are allocated from the same
+		 obstack.  So we can use the obstack associated with
+		 VR to allocate this->m_equiv.  */
+	      m_equiv = BITMAP_ALLOC (other->m_equiv->obstack);
+	      bitmap_copy (m_equiv, other->m_equiv);
+	    }
+	}
+    }
+
   if (dump_file && (dump_flags & TDF_DETAILS))
     {
       fprintf (dump_file, "to\n  ");