[llvm] [RFC] Memory Model Relaxation Annotations (PR #78569)

[Sameer Sahasrabuddhe via llvm-commits]

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+===================================
+Memory Model Relaxation Annotations
+===================================
+
+.. contents::
+   :local:
+
+Introduction
+============
+
+Memory Model Relaxation Annotations (MMRAs) are target-defined properties
+on instructions that can be used to selectively relax constraints placed
+by the memory model. For example:
+
+* The use of ``VulkanMemoryModel`` in a SPIRV program allows certain
+  memory operations to be reordered across ``acquire`` or ``release``
+  operations.
+* OpenCL APIs expose primitives to only fence a specific set of address
+  spaces, carrying that information to the backend can enable the
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ssahasra wrote:

In correct comma after "spaces".

https://github.com/llvm/llvm-project/pull/78569