hertog/godot-module-template
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Modernize atomics

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- Based on C++11's `atomic`
- Reworked `SafeRefCount` (based on the rewrite by @hpvb)
- Replaced free atomic functions by the new `SafeNumeric<T>`
- Replaced wrong cases of `volatile bool` by the new `SafeFlag`
- Platform-specific implementations no longer needed

Co-authored-by: Hein-Pieter van Braam-Stewart <hp@tmm.cx>
This commit is contained in:
Pedro J. Estébanez 2021-02-10 19:22:13 +01:00
parent 8870f43d74
commit 8e128726f0
58 changed files with 650 additions and 639 deletions
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21
core/templates/cowdata.h
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@ -45,6 +45,9 @@ class CharString;
template <class T, class V>
class VMap;
// CowData is relying on this to be true
static_assert(sizeof(SafeNumeric<uint32_t>) == sizeof(uint32_t));
template <class T>
class CowData {
template <class TV>
@ -60,12 +63,12 @@ private:
// internal helpers
_FORCE_INLINE_ uint32_t *_get_refcount() const {
_FORCE_INLINE_ SafeNumeric<uint32_t> *_get_refcount() const {
if (!_ptr) {
return nullptr;
}
return reinterpret_cast<uint32_t *>(_ptr) - 2;
return reinterpret_cast<SafeNumeric<uint32_t> *>(_ptr) - 2;
}
_FORCE_INLINE_ uint32_t *_get_size() const {
@ -192,9 +195,9 @@ void CowData<T>::_unref(void *p_data) {
return;
}
uint32_t *refc = _get_refcount();
SafeNumeric<uint32_t> *refc = _get_refcount();
if (atomic_decrement(refc) > 0) {
if (refc->decrement() > 0) {
return; // still in use
}
// clean up
@ -219,15 +222,15 @@ void CowData<T>::_copy_on_write() {
return;
}
uint32_t *refc = _get_refcount();
SafeNumeric<uint32_t> *refc = _get_refcount();
if (unlikely(*refc > 1)) {
if (unlikely(refc->get() > 1)) {
/* in use by more than me */
uint32_t current_size = *_get_size();
uint32_t *mem_new = (uint32_t *)Memory::alloc_static(_get_alloc_size(current_size), true);
*(mem_new - 2) = 1; //refcount
reinterpret_cast<SafeNumeric<uint32_t> *>(mem_new - 2)->set(1); //refcount
*(mem_new - 1) = current_size; //size
T *_data = (T *)(mem_new);
@ -278,7 +281,7 @@ Error CowData<T>::resize(int p_size) {
uint32_t *ptr = (uint32_t *)Memory::alloc_static(alloc_size, true);
ERR_FAIL_COND_V(!ptr, ERR_OUT_OF_MEMORY);
*(ptr - 1) = 0; //size, currently none
*(ptr - 2) = 1; //refcount
reinterpret_cast<SafeNumeric<uint32_t> *>(ptr - 2)->set(1); //refcount
_ptr = (T *)ptr;
@ -359,7 +362,7 @@ void CowData<T>::_ref(const CowData &p_from) {
return; //nothing to do
}
if (atomic_conditional_increment(p_from._get_refcount()) > 0) { // could reference
if (p_from._get_refcount()->increment() > 0) { // could reference
_ptr = p_from._ptr;
}
}