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

[Paul Walker via llvm-commits]

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@@ -640,6 +640,13 @@ std::string Attribute::getAsString(bool InAttrGrp) const {
       if (MR == OtherMR)
         continue;
 
+      // Dont Print Target Location if MR and target_mems ModRefInfo
+      // are NoModRef.
+      // Printing Inacessiblemem: none implies that target_mems are also
+      // not affected.
+      if (ME.isTargetMemLoc(Loc) && (MR == ModRefInfo::NoModRef))
+        continue;
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paulwalker-arm wrote:

It just occurred to me that if we're using short hand to reduce the IR output then you'll need to update `LLParser::parseMemoryAttr` because it must be applied in reverse when reading the IR back in.

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