[gcc r13-2669] Use frange::set_nan() from the generic frange::set().

[gcc r13-2669] Use frange::set_nan() from the generic frange::set().

[Aldy Hernandez]

https://gcc.gnu.org/g:4a311a6160b3def190e64ca4a05a03fbcd163598

commit r13-2669-g4a311a6160b3def190e64ca4a05a03fbcd163598
Author: Aldy Hernandez <aldyh@redhat.com>
Date:   Wed Sep 14 08:29:54 2022 +0200

    Use frange::set_nan() from the generic frange::set().
    
    This patch cleans up the frange::set() code by passing all things NAN
    to frange::set_nan().
    
    No functional changes.
    
    Regstrapped on x86-64 Linux, plus I ran selftests for
    -ffinite-math-only.
    
    gcc/ChangeLog:
    
            * value-range.cc (frange::set): Use set_nan.
            * value-range.h (frange::set_nan): Inline code originally in
            set().

Diff:
---
 gcc/value-range.cc | 27 ++++++++++++++-------------
 gcc/value-range.h  |  9 ++++++++-
 2 files changed, 22 insertions(+), 14 deletions(-)

diff --git a/gcc/value-range.cc b/gcc/value-range.cc
index dd827421aca..d759fcf178c 100644
--- a/gcc/value-range.cc
+++ b/gcc/value-range.cc
@@ -369,32 +369,33 @@ frange::set (tree min, tree max, value_range_kind kind)
       return;
     }
 
+  // Handle NANs.
+  if (real_isnan (TREE_REAL_CST_PTR (min)) || real_isnan (TREE_REAL_CST_PTR (max)))
+    {
+      gcc_checking_assert (real_identical (TREE_REAL_CST_PTR (min),
+					   TREE_REAL_CST_PTR (max)));
+      tree type = TREE_TYPE (min);
+      set_nan (type);
+      return;
+    }
+
   m_kind = kind;
   m_type = TREE_TYPE (min);
   m_props.set_varying ();
   m_min = *TREE_REAL_CST_PTR (min);
   m_max = *TREE_REAL_CST_PTR (max);
 
-  bool is_nan = (real_isnan (TREE_REAL_CST_PTR (min))
-		 || real_isnan (TREE_REAL_CST_PTR (max)));
-
-  // Ranges with a NAN and a non-NAN endpoint are nonsensical.
-  gcc_checking_assert (!is_nan || operand_equal_p (min, max));
-
-  // Set NAN property if we're absolutely sure.
-  if (is_nan && operand_equal_p (min, max))
-    m_props.nan_set_yes ();
-  else if (!HONOR_NANS (m_type))
-    m_props.nan_set_no ();
-
   // Set SIGNBIT property for positive and negative ranges.
   if (real_less (&m_max, &dconst0))
     m_props.signbit_set_yes ();
   else if (real_less (&dconst0, &m_min))
     m_props.signbit_set_no ();
 
+  if (!HONOR_NANS (m_type))
+    m_props.nan_set_no ();
+
   // Check for swapped ranges.
-  gcc_checking_assert (is_nan || tree_compare (LE_EXPR, min, max));
+  gcc_checking_assert (tree_compare (LE_EXPR, min, max));
 
   normalize_kind ();
   if (flag_checking)
diff --git a/gcc/value-range.h b/gcc/value-range.h
index 6e896eb9ab5..4392de84c8b 100644
--- a/gcc/value-range.h
+++ b/gcc/value-range.h
@@ -1193,7 +1193,14 @@ frange::set_nan (tree type)
 {
   REAL_VALUE_TYPE r;
   gcc_assert (real_nan (&r, "", 1, TYPE_MODE (type)));
-  set (type, r, r);
+  m_kind = VR_RANGE;
+  m_type = type;
+  m_min = r;
+  m_max = r;
+  m_props.set_varying ();
+  m_props.nan_set_yes ();
+  if (flag_checking)
+    verify_range ();
 }
 
 // Return TRUE if range is known to be finite.