[COMMITTED] Stream out NANs correctly.

[Aldy Hernandez <aldyh@redhat.com>]

NANs don't have bounds, so there's no need to stream them out.

gcc/ChangeLog:

	* data-streamer-in.cc (streamer_read_value_range): Handle NANs.
	* data-streamer-out.cc (streamer_write_vrange): Same.
	* value-range.h (class vrange): Make streamer_write_vrange a friend.
---
 gcc/data-streamer-in.cc  | 16 ++++++++++++----
 gcc/data-streamer-out.cc | 17 ++++++++++++-----
 gcc/value-range.h        |  1 +
 3 files changed, 25 insertions(+), 9 deletions(-)

diff --git a/gcc/data-streamer-in.cc b/gcc/data-streamer-in.cc
index 07728bef413..578c328475f 100644
--- a/gcc/data-streamer-in.cc
+++ b/gcc/data-streamer-in.cc
@@ -248,14 +248,22 @@ streamer_read_value_range (class lto_input_block *ib, data_in *data_in,
   if (is_a <frange> (vr))
     {
       frange &r = as_a <frange> (vr);
-      REAL_VALUE_TYPE lb, ub;
-      streamer_read_real_value (ib, &lb);
-      streamer_read_real_value (ib, &ub);
+
+      // Stream in NAN bits.
       struct bitpack_d bp = streamer_read_bitpack (ib);
       bool pos_nan = (bool) bp_unpack_value (&bp, 1);
       bool neg_nan = (bool) bp_unpack_value (&bp, 1);
       nan_state nan (pos_nan, neg_nan);
-      r.set (type, lb, ub, nan);
+
+      if (kind == VR_NAN)
+	r.set_nan (type, nan);
+      else
+	{
+	  REAL_VALUE_TYPE lb, ub;
+	  streamer_read_real_value (ib, &lb);
+	  streamer_read_real_value (ib, &ub);
+	  r.set (type, lb, ub, nan);
+	}
       return;
     }
   gcc_unreachable ();
diff --git a/gcc/data-streamer-out.cc b/gcc/data-streamer-out.cc
index afc9862062b..93dedfcb895 100644
--- a/gcc/data-streamer-out.cc
+++ b/gcc/data-streamer-out.cc
@@ -410,7 +410,7 @@ streamer_write_vrange (struct output_block *ob, const vrange &v)
   gcc_checking_assert (!v.undefined_p ());
 
   // Write the common fields to all vranges.
-  value_range_kind kind = v.varying_p () ? VR_VARYING : VR_RANGE;
+  value_range_kind kind = v.m_kind;
   streamer_write_enum (ob->main_stream, value_range_kind, VR_LAST, kind);
   stream_write_tree (ob, v.type (), true);
 
@@ -429,15 +429,22 @@ streamer_write_vrange (struct output_block *ob, const vrange &v)
   if (is_a <frange> (v))
     {
       const frange &r = as_a <frange> (v);
-      REAL_VALUE_TYPE lb = r.lower_bound ();
-      REAL_VALUE_TYPE ub = r.upper_bound ();
-      streamer_write_real_value (ob, &lb);
-      streamer_write_real_value (ob, &ub);
+
+      // Stream out NAN bits.
       bitpack_d bp = bitpack_create (ob->main_stream);
       nan_state nan = r.get_nan_state ();
       bp_pack_value (&bp, nan.pos_p (), 1);
       bp_pack_value (&bp, nan.neg_p (), 1);
       streamer_write_bitpack (&bp);
+
+      // Stream out bounds.
+      if (kind != VR_NAN)
+	{
+	  REAL_VALUE_TYPE lb = r.lower_bound ();
+	  REAL_VALUE_TYPE ub = r.upper_bound ();
+	  streamer_write_real_value (ob, &lb);
+	  streamer_write_real_value (ob, &ub);
+	}
       return;
     }
   gcc_unreachable ();
diff --git a/gcc/value-range.h b/gcc/value-range.h
index 39023e7b5eb..2b4ebabe7c8 100644
--- a/gcc/value-range.h
+++ b/gcc/value-range.h
@@ -76,6 +76,7 @@ class GTY((user)) vrange
 {
   template <typename T> friend bool is_a (vrange &);
   friend class Value_Range;
+  friend void streamer_write_vrange (struct output_block *, const vrange &);
 public:
   virtual void accept (const class vrange_visitor &v) const = 0;
   virtual void set (tree, tree, value_range_kind = VR_RANGE);
-- 
2.40.1