[llvm] Extend MemoryEffects to Support Target-Specific Memory Locations (PR #148650)

[Paul Walker via llvm-commits]

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@@ -640,6 +640,10 @@ std::string Attribute::getAsString(bool InAttrGrp) const {
       if (MR == OtherMR)
         continue;
 
+      // Dont want to print Target Location if NoModRef
+      if (ME.isTargetMemLoc(Loc) && (MR == ModRefInfo::NoModRef))
+        continue;
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paulwalker-arm wrote:

Thanks for the explanation.  To paraphrase, emitting `inaccessiblemem: none` is enough to imply the target_mem locations are also not affected.  It's worth expanding the comment to make this clearer.

https://github.com/llvm/llvm-project/pull/148650