pub(crate) unsafe fn llvm_optimize(
cgcx: &CodegenContext<LlvmCodegenBackend>,
dcx: DiagCtxtHandle<'_>,
module: &ModuleCodegen<ModuleLlvm>,
thin_lto_buffer: Option<&mut *mut ThinLTOBuffer>,
config: &ModuleConfig,
opt_level: OptLevel,
opt_stage: OptStage,
autodiff_stage: AutodiffStage,
) -> Result<(), FatalError>