[PPL-devel] [GIT] ppl/ppl(products): Bug in frequency() for Octagonal shapes fixed.

[Patricia Hill]

Module: ppl/ppl
Branch: products
Commit: 0ef46ef0cbc64d9f9a472d433abf01507fd078fd
URL:    http://www.cs.unipr.it/git/gitweb.cgi?p=ppl/ppl.git;a=commit;h=0ef46ef0cbc64d9f9a472d433abf01507fd078fd

Author: Patricia Hill <p.m.hill at leeds.ac.uk>
Date:   Sat May 23 20:55:47 2009 +0100

Bug in frequency() for Octagonal shapes fixed.

---

 src/Octagonal_Shape.templates.hh    |   30 +++++++++++++++-----
 tests/Octagonal_Shape/frequency1.cc |   50 +++++++++++++++++++++++++++++++++++
 2 files changed, 72 insertions(+), 8 deletions(-)

diff --git a/src/Octagonal_Shape.templates.hh b/src/Octagonal_Shape.templates.hh
index 8793f09..b3faa2a 100644
--- a/src/Octagonal_Shape.templates.hh
+++ b/src/Octagonal_Shape.templates.hh
@@ -983,13 +983,8 @@ Octagonal_Shape<T>::frequency(const Linear_Expression& expr,
         const dimension_type cj = coherent_index(j);
         const dimension_type cjj = coherent_index(j+1);
 
-        // Check if we want the sum or difference constraint.
-        // If the coefficients for `v' and `vj' are the same, use
-        // the sum constraint, otherwise use the difference constraint.
-        bool same_sign = (sgn(coeff) == sgn(coeff_j));
-
-        Row_Reference m_j = (same_sign) ? *(m_begin + j + 1) : *(m_begin + j);
-        Row_Reference m_cj = (same_sign) ? *(m_begin + cjj) : *(m_begin + cj);
+        Row_Reference m_j = *(m_begin + j);
+        Row_Reference m_cj = *(m_begin + cj);
         const N& m_j_i = m_j[i];
         const N& m_i_j = m_cj[ci];
         if ((!is_plus_infinity(m_i_j) && !is_plus_infinity(m_j_i))
@@ -999,7 +994,26 @@ Octagonal_Shape<T>::frequency(const Linear_Expression& expr,
           // So apply this equality to eliminate `v' in `le'.
           numer_denom(m_i_j, num, den);
           le -= coeff*v;
-          le = (same_sign) ? le - coeff*vj :  le + coeff*vj;
+          le = le + coeff*vj;
+          le *= den;
+          le = le - num*coeff;
+          val_den *= den;
+          constant_v = true;
+          break;
+        }
+
+        m_j = *(m_begin + j + 1);
+        m_cj = *(m_begin + cjj);
+        const N& m_j_i1 = m_j[i];
+        const N& m_i_j1 = m_cj[ci];
+        if ((!is_plus_infinity(m_i_j1) && !is_plus_infinity(m_j_i1))
+            && (is_additive_inverse(m_i_j1, m_j_i1))) {
+          // The coefficient for `vj' in `le' is not 0
+          // and the constraint with `v' is an equality.
+          // So apply this equality to eliminate `v' in `le'.
+          numer_denom(m_i_j1, num, den);
+          le -= coeff*v;
+          le = le - coeff*vj;
           le *= den;
           le = le - num*coeff;
           val_den *= den;
diff --git a/tests/Octagonal_Shape/frequency1.cc b/tests/Octagonal_Shape/frequency1.cc
index 293cc8b..02a8754 100644
--- a/tests/Octagonal_Shape/frequency1.cc
+++ b/tests/Octagonal_Shape/frequency1.cc
@@ -243,6 +243,54 @@ test10() {
   return ok;
 }
 
+bool
+test11() {
+  Variable A(0);
+  Variable B(1);
+  Variable C(2);
+
+  TOctagonal_Shape os(3);
+  os.add_constraint(2*A + 2*B == 1);
+  os.add_constraint(B - C == 1);
+  os.add_constraint(B <= 2);
+
+  Coefficient num;
+  Coefficient den;
+  Coefficient valn;
+  Coefficient vald;
+  bool ok = (os.frequency(Linear_Expression(A - B + 2*C + 1),
+                           num, den, valn, vald)
+             && num == 0 && den == 1 && valn == -1 && vald == 2);
+  print_constraints(os, "*** os ***");
+  nout << "valn " << valn << ", vald " << vald << endl;
+
+  return ok;
+}
+
+bool
+test12() {
+  Variable A(0);
+  Variable B(1);
+  Variable C(2);
+
+  TOctagonal_Shape os(3);
+  os.add_constraint(2*A - 2*B == 1);
+  os.add_constraint(B + C == 1);
+  os.add_constraint(B <= 2);
+
+  Coefficient num;
+  Coefficient den;
+  Coefficient valn;
+  Coefficient vald;
+  bool ok = (os.frequency(Linear_Expression(A + B + 2*C + 1),
+                           num, den, valn, vald)
+             && num == 0 && den == 1 && valn == 7 && vald == 2);
+  print_constraints(os, "*** os ***");
+  nout << "valn " << valn << ", vald " << vald << endl;
+
+  return ok;
+}
+
 } // namespace
 
 BEGIN_MAIN
@@ -256,4 +304,6 @@ BEGIN_MAIN
   DO_TEST(test08);
   DO_TEST(test09);
   DO_TEST(test10);
+  DO_TEST(test11);
+  DO_TEST(test12);
 END_MAIN