[llvm] [MemProf] Print full context hash when reporting hinted bytes (PR #114465)

[Teresa Johnson via llvm-commits]

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@@ -4404,6 +4410,24 @@ void ModuleBitcodeWriterBase::writePerModuleGlobalValueSummary() {
     Stream.EmitRecord(bitc::FS_STACK_IDS, Index->stackIds(), StackIdAbbvId);
   }
 
+  SmallVector<uint64_t, 64> NameVals;
+  if (!Index->contextSizeInfos().empty()) {
+    auto ContextSizeInfoAbbv = std::make_shared<BitCodeAbbrev>();
+    ContextSizeInfoAbbv->Add(BitCodeAbbrevOp(bitc::FS_CONTEXT_SIZE_INFOS));
+    // numids x (fullStackid, totalsize)
+    ContextSizeInfoAbbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
+    ContextSizeInfoAbbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
+    unsigned ContextSizeInfoAbbvId =
+        Stream.EmitAbbrev(std::move(ContextSizeInfoAbbv));
+    for (const auto &Info : Index->contextSizeInfos()) {
+      NameVals.push_back(Info.FullStackId);
+      NameVals.push_back(Info.TotalSize);
+    }
+    Stream.EmitRecord(bitc::FS_CONTEXT_SIZE_INFOS, NameVals,
+                      ContextSizeInfoAbbvId);
+    NameVals.clear();
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teresajohnson wrote:

Is it worth it? We reuse this vector multiple times for other records. And the lifetime is not so long that it is going to make any noticeable difference on memory (this is in the pre-lto link compile).

https://github.com/llvm/llvm-project/pull/114465