diff --git a/src/Pipeline/SpirvShader.cpp b/src/Pipeline/SpirvShader.cpp
index d70e0ea..c630bfa 100644
--- a/src/Pipeline/SpirvShader.cpp
+++ b/src/Pipeline/SpirvShader.cpp
@@ -3376,7 +3376,11 @@
 		}
 		case GLSLstd450Acosh:
 		{
-			UNIMPLEMENTED("GLSLstd450Acosh");
+			auto val = GenericValue(this, routine, insn.word(5));
+			for (auto i = 0u; i < type.sizeInComponents; i++)
+			{
+				dst.move(i, Acosh(val.Float(i)));
+			}
 			break;
 		}
 		case GLSLstd450Atanh:
diff --git a/src/Reactor/LLVMReactor.cpp b/src/Reactor/LLVMReactor.cpp
index d105d3e..f31119e 100644
--- a/src/Reactor/LLVMReactor.cpp
+++ b/src/Reactor/LLVMReactor.cpp
@@ -563,6 +563,7 @@
 			func_.emplace("coshf", reinterpret_cast<void*>(coshf));
 			func_.emplace("tanhf", reinterpret_cast<void*>(tanhf));
 			func_.emplace("asinhf", reinterpret_cast<void*>(asinhf));
+			func_.emplace("acoshf", reinterpret_cast<void*>(acoshf));
 
 #ifdef __APPLE__
 			// LLVM uses this function on macOS for tan.
@@ -3144,6 +3145,11 @@
 		return TransformFloat4PerElement(v, "asinhf");
 	}
 
+	RValue<Float4> Acosh(RValue<Float4> v)
+	{
+		return TransformFloat4PerElement(v, "acoshf");
+	}
+
 	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 ffbd7c8..7609307 100644
--- a/src/Reactor/Reactor.hpp
+++ b/src/Reactor/Reactor.hpp
@@ -2218,6 +2218,7 @@
 	RValue<Float4> Cosh(RValue<Float4> x);
 	RValue<Float4> Tanh(RValue<Float4> x);
 	RValue<Float4> Asinh(RValue<Float4> x);
+	RValue<Float4> Acosh(RValue<Float4> x);
 
 	template<class T>
 	class Pointer : public LValue<Pointer<T>>