Tasks completed: - Pattern match`select(fcmp(dot(p2, p3), 0), p1, -p1)` to `faceforward(p1, p2, p3)` - Add pattern matching tests to `prelegalizercombiner-select-to-faceforward.mir` and `faceforward.ll` - Add CL extension error test `llvm/test/CodeGen/SPIRV/opencl/faceforward-error.ll` - Add CL extension test for no pattern matching in `llvm/test/CodeGen/SPIRV/opencl/faceforward.ll` Closes #137255.