Microsoft, and Google have been partnering to add HLSL support to Clang which includes full code generation support for DirectX's DXIL intermediate format and Vulkan's SPIR-V. In this effort we've invested significantly in a new testing infrastructure to enable our project goals. This talk will discuss the project goals, provide an overview of the testing infrastructure, and some early data and real world results demonstrating the value we're already seeing from the infrastructure.