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Add atomics for 64-bit integers

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This commit is contained in:
Pedro J. Estébanez 2017-06-22 05:05:59 +02:00
parent 59322d4cc4
commit 0b776f9a30
2 changed files with 71 additions and 0 deletions
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67
core/safe_refcount.cpp
View file

@ -57,6 +57,30 @@ uint32_t atomic_decrement(register uint32_t *pw) {
return *pw;
}
uint64_t atomic_conditional_increment(register uint64_t *pw) {
if (*pw == 0)
return 0;
(*pw)++;
return *pw;
}
uint64_t atomic_increment(register uint64_t *pw) {
(*pw)++;
return *pw;
}
uint64_t atomic_decrement(register uint64_t *pw) {
(*pw)--;
return *pw;
}
#else
#ifdef _MSC_VER
@ -84,6 +108,28 @@ uint32_t atomic_decrement(register uint32_t *pw) {
uint32_t atomic_increment(register uint32_t *pw) {
return InterlockedIncrement((LONG volatile *)pw);
}
uint64_t atomic_conditional_increment(register uint64_t *pw) {
/* try to increment until it actually works */
// taken from boost
while (true) {
uint64_t tmp = static_cast<uint64_t const volatile &>(*pw);
if (tmp == 0)
return 0; // if zero, can't add to it anymore
if (InterlockedCompareExchange64((LONGLONG volatile *)pw, tmp + 1, tmp) == tmp)
return tmp + 1;
}
}
uint64_t atomic_decrement(register uint64_t *pw) {
return InterlockedDecrement64((LONGLONG volatile *)pw);
}
uint64_t atomic_increment(register uint64_t *pw) {
return InterlockedIncrement64((LONGLONG volatile *)pw);
}
#elif defined(__GNUC__)
uint32_t atomic_conditional_increment(register uint32_t *pw) {
@ -107,6 +153,27 @@ uint32_t atomic_increment(register uint32_t *pw) {
return __sync_add_and_fetch(pw, 1);
}
uint64_t atomic_conditional_increment(register uint64_t *pw) {
while (true) {
uint64_t tmp = static_cast<uint64_t const volatile &>(*pw);
if (tmp == 0)
return 0; // if zero, can't add to it anymore
if (__sync_val_compare_and_swap(pw, tmp, tmp + 1) == tmp)
return tmp + 1;
}
}
uint64_t atomic_decrement(register uint64_t *pw) {
return __sync_sub_and_fetch(pw, 1);
}
uint64_t atomic_increment(register uint64_t *pw) {
return __sync_add_and_fetch(pw, 1);
}
#else
//no threads supported?
#error Must provide atomic functions for this platform or compiler!

4
core/safe_refcount.h
View file

@ -40,6 +40,10 @@ uint32_t atomic_conditional_increment(register uint32_t *counter);
uint32_t atomic_decrement(register uint32_t *pw);
uint32_t atomic_increment(register uint32_t *pw);
uint64_t atomic_conditional_increment(register uint64_t *counter);
uint64_t atomic_decrement(register uint64_t *pw);
uint64_t atomic_increment(register uint64_t *pw);
struct SafeRefCount {
uint32_t count;