From fe32e0c578abd1c13a82889217021813d6a29388 Mon Sep 17 00:00:00 2001
From: Chris Lattner <sabre@nondot.org>
Date: Wed, 30 Apr 2003 22:19:10 +0000
Subject: [PATCH] Fix constant folding of constexprs

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@5971 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Transforms/Scalar/InstructionCombining.cpp | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp
index 70fc952891f..ad4ef420e9d 100644
--- a/lib/Transforms/Scalar/InstructionCombining.cpp
+++ b/lib/Transforms/Scalar/InstructionCombining.cpp
@@ -186,12 +186,9 @@ static inline Value *dyn_castNegVal(Value *V) {
   if (BinaryOperator::isNeg(V))
     return BinaryOperator::getNegArgument(cast<BinaryOperator>(V));
 
-  // Constants can be considered to be negated values...
-  if (Constant *C = dyn_cast<Constant>(V)) {
-    Constant *NC = *Constant::getNullValue(V->getType()) - *C;
-    assert(NC && "Couldn't constant fold a subtract!");
-    return NC;
-  }
+  // Constants can be considered to be negated values if they can be folded...
+  if (Constant *C = dyn_cast<Constant>(V))
+    return *Constant::getNullValue(V->getType()) - *C;
   return 0;
 }