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[libc][stdlib] Remove LIBC_THREAD_LOCAL from rand_next #96245

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[libc][stdlib] Remove LIBC_THREAD_LOCAL from rand_next #96245

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4 changes: 2 additions & 2 deletions libc/src/stdlib/rand_util.cpp
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Expand Up @@ -14,11 +14,11 @@ namespace LIBC_NAMESPACE {
#ifdef LIBC_TARGET_ARCH_IS_GPU
// FIXME: Local GPU memory cannot be initialized so we cannot currently provide
// a standard compliant default value.
ThreadLocal<unsigned long> rand_next;
unsigned long rand_next;
#else
// C standard 7.10p2: If 'rand' is called before 'srand' it is to proceed as if
// the 'srand' function was called with a value of '1'.
LIBC_THREAD_LOCAL unsigned long rand_next = 1;
unsigned long rand_next = 1;
#endif

} // namespace LIBC_NAMESPACE
23 changes: 1 addition & 22 deletions libc/src/stdlib/rand_util.h
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Expand Up @@ -14,28 +14,7 @@

namespace LIBC_NAMESPACE {

#ifdef LIBC_TARGET_ARCH_IS_GPU
// Implement thread local storage on the GPU using local memory. Each thread
// gets its slot in the local memory array and is private to the group.
// TODO: We need to implement the 'thread_local' keyword on the GPU. This is an
// inefficient and incomplete stand-in until that is done.
template <typename T> class ThreadLocal {
private:
static constexpr long MAX_THREADS = 1024;
[[clang::loader_uninitialized]] static inline gpu::Local<T>
storage[MAX_THREADS];

public:
LIBC_INLINE operator T() const { return storage[gpu::get_thread_id()]; }
LIBC_INLINE void operator=(const T &value) {
storage[gpu::get_thread_id()] = value;
}
};

extern ThreadLocal<unsigned long> rand_next;
#else
extern LIBC_THREAD_LOCAL unsigned long rand_next;
#endif
extern unsigned long rand_next;

} // namespace LIBC_NAMESPACE

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