[V4] Fixed capacity deque (#74)

* pop hardware warning

* fix shadow warning

* doc patch

* modernize ring-buffer

* comments

* fixed-cap dequeue

* round to power of 2

* fix tests/benchmark

* confirm cdschecker bug fixed

* harden empty/size

* vet(push): comments

* vet(pop): move load to position from rust/paper

* stealer API

* spell

* fix wrong-op

Author: ConorWilliams

benchmark/src/libfork_benchmark/fib/baremetal.cpp

@@ -139,7 +139,7 @@ void fib_recursive_deque(benchmark::State &state) {
 
   state.counters["n"] = static_cast<double>(n);
 
-  lf::deque<std::int64_t> deque;
+  lf::deque<std::int64_t> deque{64};
   tls_deque = &deque;
 
   for (auto _ : state) {

benchmark/src/libfork_benchmark/fib/lf_parts.cpp

@@ -78,7 +78,7 @@ struct deque_ctx {
 
   using handle_type = lf::frame_handle<deque_ctx>;
 
-  lf::deque<handle_type> work;
+  lf::deque<handle_type> work{64};
   Alloc my_allocator;
 
   auto allocator() noexcept -> Alloc & { return my_allocator; }
@@ -121,7 +121,7 @@ struct poly_deque_ctx final : lf::basic_poly_context<Alloc> {
 
   using handle_type = lf::frame_handle<lf::basic_poly_context<Alloc>>;
 
-  lf::deque<handle_type> work;
+  lf::deque<handle_type> work{64};
 
   void post(lf::await_handle<lf::basic_poly_context<Alloc>>) override {}
 

src/core/constants.cxx

@@ -10,7 +10,15 @@ constexpr std::size_t k_megabyte = 1024 * k_kilobyte;
 constexpr std::uint32_t k_u16_max = std::numeric_limits<std::uint16_t>::max();
 
 export constexpr std::size_t k_new_align = __STDCPP_DEFAULT_NEW_ALIGNMENT__;
-export constexpr std::size_t k_cache_line = std::hardware_destructive_interference_size;
 export constexpr std::size_t k_page_size = 4096; // 4 KiB on most systems.
 
+#if defined(__GNUC__) && !defined(__clang__) && !defined(__INTEL_COMPILER)
+  #pragma GCC diagnostic push
+  #pragma GCC diagnostic ignored "-Winterference-size"
+#endif // #ifdef __GNUC__
+export constexpr std::size_t k_cache_line = std::hardware_destructive_interference_size;
+#if defined(__GNUC__) && !defined(__clang__) && !defined(__INTEL_COMPILER)
+  #pragma GCC diagnostic pop
+#endif // #ifdef __GNUC__
+
 } // namespace lf