Prefetch/ Memadvice should be `const`

[TApplencourt]

Specification Version

SYCL 2020 (Revision 11)

Section Number(s)

somehere

Bug Description

  event prefetch(void* ptr, std::size_t numBytes);
  event prefetch(void* ptr, std::size_t numBytes, event depEvent);
  event prefetch(void* ptr, std::size_t numBytes,
                 const std::vector<event>& depEvents);

  /* -- Shortcut functions: mem_advise -- */

  event mem_advise(void* ptr, std::size_t numBytes, int advice);
  event mem_advise(void* ptr, std::size_t numBytes, int advice, event depEvent);
  event mem_advise(void* ptr, std::size_t numBytes, int advice,
                   const std::vector<event>& depEvents);

Adabtivecpp: already implemented as const
DPCP: Maybe?

• For sure will clarify into launch_queue khr
• Maybe clarification fix into SYCL 2020

[gmlueck]

I confirm that DPC++ already declares the following member functions as const void * instead of void *:

class queue {
  event prefetch(const void* ptr, std::size_t numBytes);
  event prefetch(const void* ptr, std::size_t numBytes, event depEvent);
  event prefetch(const void* ptr, std::size_t numBytes,
                 const std::vector<event>& depEvents);

  event mem_advise(const void* ptr, std::size_t numBytes, int advice);
  event mem_advise(const void* ptr, std::size_t numBytes, int advice, event depEvent);
  event mem_advise(const void* ptr, std::size_t numBytes, int advice,
                   const std::vector<event>& depEvents);
};

class handler {
  void prefetch(const void* ptr, std::size_t numBytes);
  void mem_advise(const void* ptr, std::size_t numBytes, int advice);
};

Therefore, we would also be in favor of changing the spec to match.

[TApplencourt]

PR Needed (need to change Prefetech Host too #960)