[Openmp-commits] [PATCH] D105812: [libomptarget] Update device pointer only if needed

[Joel E. Denny via Phabricator via Openmp-commits]

jdenny added inline comments.


================
Comment at: openmp/libomptarget/test/mapping/device_ptr_update.c:20
+#pragma omp target enter data map(alloc:s1.p[0:10])
+
+  // DEBUG-NOT: Update pointer ([[DEV_PTR]]) -> {{\[}}[[DEV_OBJ_A]]{{\]}}
----------------
Assume we insert `s1.p = B` here.  Without this patch, the target directive below then changes `s1.p` on the device, but it doesn't with this patch, right?

However, I don't think OpenMP permits that line to be inserted in the case of C/C++:

> A pointer that has a corresponding attached pointer must not be modified for the duration of the lifetime of the list item to which the corresponding pointer is attached in the device data environment.

This patch can then be considered as purely an optimization, right?


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D105812/new/

https://reviews.llvm.org/D105812