[PUSHED] Replace !irange::undefined_p checks with num_ranges > 0 for readability.

[Aldy Hernandez via Gcc-patches]

A few of the undefined_p checks in the irange code are really checking if
there are sub-ranges.  It just so happens that undefined_p is
implemented with num_ranges > 0, so it was a shorthand used throughout.
This shorthand was making the code unreadable.

gcc/ChangeLog:

        * value-range.cc (irange::legacy_lower_bound): Replace
          !undefined_p check with num_ranges > 0.
        (irange::legacy_upper_bound): Same.
        * value-range.h (irange::type): Same.
        (irange::lower_bound): Same.
        (irange::upper_bound): Same.
---
 gcc/value-range.cc | 4 ++--
 gcc/value-range.h  | 6 +++---
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/gcc/value-range.cc b/gcc/value-range.cc
index cd21f75909b..d46662397e7 100644
--- a/gcc/value-range.cc
+++ b/gcc/value-range.cc
@@ -441,7 +441,7 @@ irange::legacy_lower_bound (unsigned pair) const
       numeric_range.normalize_symbolics ();
       return numeric_range.legacy_lower_bound (pair);
     }
-  gcc_checking_assert (!undefined_p ());
+  gcc_checking_assert (m_num_ranges > 0);
   gcc_checking_assert (pair + 1 <= num_pairs ());
   if (m_kind == VR_ANTI_RANGE)
     {
@@ -468,7 +468,7 @@ irange::legacy_upper_bound (unsigned pair) const
       numeric_range.normalize_symbolics ();
       return numeric_range.legacy_upper_bound (pair);
     }
-  gcc_checking_assert (!undefined_p ());
+  gcc_checking_assert (m_num_ranges > 0);
   gcc_checking_assert (pair + 1 <= num_pairs ());
   if (m_kind == VR_ANTI_RANGE)
     {
diff --git a/gcc/value-range.h b/gcc/value-range.h
index bfc54a2473f..bb27e706207 100644
--- a/gcc/value-range.h
+++ b/gcc/value-range.h
@@ -224,7 +224,7 @@ irange::num_pairs () const
 inline tree
 irange::type () const
 {
-  gcc_checking_assert (!undefined_p ());
+  gcc_checking_assert (m_num_ranges > 0);
   return TREE_TYPE (m_base[0]);
 }
 
@@ -501,7 +501,7 @@ irange::lower_bound (unsigned pair) const
 {
   if (legacy_mode_p ())
     return legacy_lower_bound (pair);
-  gcc_checking_assert (!undefined_p ());
+  gcc_checking_assert (m_num_ranges > 0);
   gcc_checking_assert (pair + 1 <= num_pairs ());
   return wi::to_wide (tree_lower_bound (pair));
 }
@@ -514,7 +514,7 @@ irange::upper_bound (unsigned pair) const
 {
   if (legacy_mode_p ())
     return legacy_upper_bound (pair);
-  gcc_checking_assert (!undefined_p ());
+  gcc_checking_assert (m_num_ranges > 0);
   gcc_checking_assert (pair + 1 <= num_pairs ());
   return wi::to_wide (tree_upper_bound (pair));
 }
-- 
2.30.2