diff --git a/src/Pipeline/SpirvShader.cpp b/src/Pipeline/SpirvShader.cpp
index 7975872..ad3d08f 100644
--- a/src/Pipeline/SpirvShader.cpp
+++ b/src/Pipeline/SpirvShader.cpp
@@ -3293,6 +3293,15 @@
 			}
 			break;
 		}
+		case GLSLstd450Cos:
+		{
+			auto radians = GenericValue(this, routine, insn.word(5));
+			for (auto i = 0u; i < type.sizeInComponents; i++)
+			{
+				dst.move(i, Cos(radians.Float(i)));
+			}
+			break;
+		}
 		default:
 			UNIMPLEMENTED("Unhandled ExtInst %d", extInstIndex);
 		}
diff --git a/src/Reactor/LLVMReactor.cpp b/src/Reactor/LLVMReactor.cpp
index abe35df..578dfa1 100644
--- a/src/Reactor/LLVMReactor.cpp
+++ b/src/Reactor/LLVMReactor.cpp
@@ -555,6 +555,7 @@
 			func_.emplace("puts", reinterpret_cast<void*>(puts));
 			func_.emplace("fmodf", reinterpret_cast<void*>(fmodf));
 			func_.emplace("sinf", reinterpret_cast<void*>(sinf));
+			func_.emplace("cosf", reinterpret_cast<void*>(cosf));
 		}
 
 		void *findSymbol(const std::string &name) const
@@ -3070,6 +3071,12 @@
 		return RValue<Float4>(V(::builder->CreateCall(func, V(v.value))));
 	}
 
+	RValue<Float4> Cos(RValue<Float4> v)
+	{
+		auto func = llvm::Intrinsic::getDeclaration(::module, llvm::Intrinsic::cos, { V(v.value)->getType() } );
+		return RValue<Float4>(V(::builder->CreateCall(func, V(v.value))));
+	}
+
 	Type *Float4::getType()
 	{
 		return T(llvm::VectorType::get(T(Float::getType()), 4));
diff --git a/src/Reactor/Reactor.hpp b/src/Reactor/Reactor.hpp
index 41e15c8..2419dbe 100644
--- a/src/Reactor/Reactor.hpp
+++ b/src/Reactor/Reactor.hpp
@@ -2209,6 +2209,7 @@
 	// Trigonometric functions
 	// TODO: Currentlhy unimplemented for Subzero.
 	RValue<Float4> Sin(RValue<Float4> x);
+	RValue<Float4> Cos(RValue<Float4> x);
 
 	template<class T>
 	class Pointer : public LValue<Pointer<T>>