Index: include/llvm/IR/Operator.h
===================================================================
--- include/llvm/IR/Operator.h
+++ include/llvm/IR/Operator.h
@@ -232,6 +232,7 @@
       setHasNoInfs(true);
       setHasNoSignedZeros(true);
       setHasAllowReciprocal(true);
+      setHasAllowContract(true);
     }
   }
 
Index: unittests/IR/IRBuilderTest.cpp
===================================================================
--- unittests/IR/IRBuilderTest.cpp
+++ unittests/IR/IRBuilderTest.cpp
@@ -227,6 +227,24 @@
 
   Builder.clearFastMathFlags();
 
+  FC = Builder.CreateFAdd(F, F);
+  EXPECT_FALSE(Builder.getFastMathFlags().any());
+  ASSERT_TRUE(isa<Instruction>(FC));
+  FAdd = cast<Instruction>(FC);
+  EXPECT_FALSE(FAdd->hasNoNaNs());
+  EXPECT_FALSE(FAdd->hasNoInfs());
+  EXPECT_FALSE(FAdd->hasNoSignedZeros());
+  EXPECT_FALSE(FAdd->hasAllowReciprocal());
+  EXPECT_FALSE(FAdd->hasAllowContract());
+  EXPECT_FALSE(FAdd->hasUnsafeAlgebra());
+  FAdd->setHasUnsafeAlgebra(true);
+  EXPECT_TRUE(FAdd->hasNoNaNs());
+  EXPECT_TRUE(FAdd->hasNoInfs());
+  EXPECT_TRUE(FAdd->hasNoSignedZeros());
+  EXPECT_TRUE(FAdd->hasAllowReciprocal());
+  EXPECT_TRUE(FAdd->hasAllowContract());
+  EXPECT_TRUE(FAdd->hasUnsafeAlgebra());
+
   // Test a call with FMF.
   auto CalleeTy = FunctionType::get(Type::getFloatTy(Ctx),
                                     /*isVarArg=*/false);