[llvm] [OFFLOAD] Extend olMemRegister API to handle cases when a memory block may have been mapped outside of liboffload. (PR #172226)

[Kevin Sala Penades via llvm-commits]

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@@ -143,7 +152,8 @@ def olMemRegister : Function {
         "Pins host memory to optimize transfers and returns the device accessible",
         "stable pointer that devices should use for memory transfers involving the host",
         "pinned allocation. If the buffer intersects with other existing buffer,",
-        "a new user will be registered. A partial overlapping is not allowed.",
+        "if the buffer is locked outside of this API, or Flags doesn't contain LOCK_MEMORY 
+        "flag a new user will be registered. A partial overlapping is not allowed.",
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kevinsala wrote:

`Partial overlapping with an already registered range is not allowed.`

https://github.com/llvm/llvm-project/pull/172226