commit d38f208cd97832babc72abe0f4887fbcb5d44b11
author Chris Lattner <sabre@nondot.org> Tue Feb 24 18:10:14 2004 +0000
committer Chris Lattner <sabre@nondot.org> Tue Feb 24 18:10:14 2004 +0000
tree e2a85e990f6657f7e41d536f271d032ee9661d5f
parent 6e4ca614380bdbbf051562f05560024d35aeccfe

Fix a faulty optimization on FP values


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11801 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Transforms/Scalar/InstructionCombining.cpp

diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp
index fb7dc98..322112a 100644
--- a/lib/Transforms/Scalar/InstructionCombining.cpp
+++ b/lib/Transforms/Scalar/InstructionCombining.cpp
@@ -441,7 +441,8 @@
   Value *LHS = I.getOperand(0), *RHS = I.getOperand(1);
 
   // X + 0 --> X
-  if (RHS == Constant::getNullValue(I.getType()))
+  if (!I.getType()->isFloatingPoint() &&    // -0 + +0 = +0, so it's not a noop
+      RHS == Constant::getNullValue(I.getType()))
     return ReplaceInstUsesWith(I, LHS);
 
   // X + X --> X << 1