Support partial folding for Add in new constant folding builder.

git-svn-id: https://llvm.org/svn/llvm-project/klee/trunk@73363 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 6 insertions, 0 deletions

diff --git a/lib/Expr/Expr.cpp b/lib/Expr/Expr.cpp
index 5ef71d8c..b6833f24 100644
--- a/lib/Expr/Expr.cpp
+++ b/lib/Expr/Expr.cpp
@@ -373,6 +373,12 @@ ref<ConstantExpr> ConstantExpr::Add(const ref<ConstantExpr> &RHS) {
                               getWidth());
 }
 
+ref<ConstantExpr> ConstantExpr::Neg() {
+  return ConstantExpr::create(ints::sub(0, 
+                                        getConstantValue(), getWidth()),
+                              getWidth());
+}
+
 ref<ConstantExpr> ConstantExpr::Sub(const ref<ConstantExpr> &RHS) {
   return ConstantExpr::create(ints::sub(getConstantValue(), 
                                         RHS->getConstantValue(), getWidth()),