Index: lib/Analysis/ConstantFolding.cpp
===================================================================
--- lib/Analysis/ConstantFolding.cpp
+++ lib/Analysis/ConstantFolding.cpp
@@ -1234,6 +1234,8 @@
   case Intrinsic::floor:
   case Intrinsic::ceil:
   case Intrinsic::sqrt:
+  case Intrinsic::sin:
+  case Intrinsic::cos:
   case Intrinsic::pow:
   case Intrinsic::powi:
   case Intrinsic::bswap:
@@ -1450,6 +1452,10 @@
           return ConstantFoldFP(floor, V, Ty);
         case Intrinsic::ceil:
           return ConstantFoldFP(ceil, V, Ty);
+        case Intrinsic::sin:
+          return ConstantFoldFP(sin, V, Ty);
+        case Intrinsic::cos:
+          return ConstantFoldFP(cos, V, Ty);
       }
 
       if (!TLI)
Index: test/Transforms/InstCombine/intrinsics.ll
===================================================================
--- test/Transforms/InstCombine/intrinsics.ll
+++ test/Transforms/InstCombine/intrinsics.ll
@@ -17,6 +17,10 @@
 declare i32 @llvm.ctlz.i32(i32, i1) nounwind readnone
 declare i32 @llvm.ctpop.i32(i32) nounwind readnone
 declare i8 @llvm.ctlz.i8(i8, i1) nounwind readnone
+declare double @llvm.cos.f64(double %Val) nounwind readonly
+declare double @llvm.sin.f64(double %Val) nounwind readonly
+
+
 
 define i8 @uaddtest1(i8 %A, i8 %B) {
   %x = call %overflow.result @llvm.uadd.with.overflow.i8(i8 %A, i8 %B)
@@ -425,3 +429,24 @@
 ; CHECK-NEXT: %[[x:.*]] = insertvalue %ov.result.32 { i32 undef, i1 false }, i32 %a, 0
 ; CHECK-NEXT:  ret %ov.result.32 %[[x]]
 }
+
+define void @cos(double *%P) {
+entry:
+  %B = tail call double @llvm.cos.f64(double 0.0) nounwind
+  store volatile double %B, double* %P
+
+  ret void
+; CHECK-LABEL: @cos(
+; CHECK: store volatile double 1.000000e+00, double* %P
+}
+
+define void @sin(double *%P) {
+entry:
+  %B = tail call double @llvm.sin.f64(double 0.0) nounwind
+  store volatile double %B, double* %P
+
+  ret void
+; CHECK-LABEL: @sin(
+; CHECK: store volatile double 0.000000e+00, double* %P
+}
+