diff options
| -rw-r--r-- | src/layer.cc | 31 |
1 files changed, 13 insertions, 18 deletions
diff --git a/src/layer.cc b/src/layer.cc index b4766eb..e9ddbb5 100644 --- a/src/layer.cc +++ b/src/layer.cc @@ -195,11 +195,9 @@ static VKAPI_ATTR VkResult VKAPI_CALL CreateDevice( // an env var and AL2 is requested at the device level via the extension, // the cases where we exit with a bad code or deliberately no-op are: // - // !SUPPORTED && !AL2 && !AL1 -> No-op hooks // !SUPPORTED && !AL2 && AL1 -> No-op hooks - // !SUPPORTED && AL2 && !AL1 -> VK_ERROR_INITIALIZATION_FAILED - // !SUPPORTED && AL2 && AL1 -> VK_ERROR_INITIALIZATION_FAILED - // SUPPORTED && !AL2 && !AL1 -> No-op hooks. + // !AL2 && !AL1 -> No-op hooks. + // !SUPPORTED && AL2 -> VK_ERROR_INITIALIZATION_FAILED // // Note that even though the user has explicitly enabled AL1 via an env var, // failing hard here by returning INIT_FAILED if the device doesn't support @@ -616,24 +614,21 @@ AntiLagUpdateAMD(VkDevice device, const VkAntiLagDataAMD* pData) { // This is a bit of template hackery which generates a wrapper function for each // of our hooks that keeps exceptions from getting sucked back into the caller. -// This is useful because it allows us to use exceptions and not violate the -// vulkan contract. If we can return something, VK_ERROR_UNKNOWN is used - -// otherwise we call terminate. +// This is useful because we don't want to violate the Vulkan ABI by accident in +// the case that we don't use try/catch somewhere. It's also useful because we +// only use exceptions in unrecoverable absolute failure cases. This means that +// we can just write our code while ignoring the potential for it to throw and +// have errors somewhat gracefully handled by this wrapper. +// +// I was considering mapping certain exception types like std::out_of_memory to +// their vulkan equivalent (only when allowed by the API). In the end I think +// it's just bloat and ultimately less informative than a 'VK_ERROR_UNKNOWN' +// because then the caller knows that it probably wasn't triggered as part of +// the standard Vulkan codepath. It simplifies things here too to just this. template <auto Func> struct HookExceptionWrapper; template <typename R, typename... Args, R (*Func)(Args...)> struct HookExceptionWrapper<Func> { static R call(Args... args) noexcept { - - // If the function is void, we don't need to think about anything and - // can just call it. - if constexpr (std::is_void_v<R>) { - Func(args...); - return; - } - - // If the function isn't void, we need to wrap it in a try block. Any - // exceptions we get (which came from our layer) should handled here - // by returning VK_ERROR_UNKNOWN when we can. Otherwise just terminate. try { return Func(args...); } catch (...) { |