[llvm] [memprof] Add Version2 of the indexed MemProf format (PR #89100)

[Snehasish Kumar via llvm-commits]

================
@@ -450,6 +474,67 @@ TEST_F(InstrProfTest, test_memprof) {
   EXPECT_THAT(WantRecord, EqualsRecord(Record));
 }
 
+TEST_F(InstrProfTest, test_memprof_v2) {
+  Writer.setMemProfVersionRequested(memprof::Version2);
+
+  ASSERT_THAT_ERROR(Writer.mergeProfileKind(InstrProfKind::MemProf),
+                    Succeeded());
+
+  const IndexedMemProfRecord IndexedMR = makeRecordV2(
+      /*AllocFrames=*/{0x111, 0x222},
+      /*CallSiteFrames=*/{0x333});
+  const FrameIdMapTy IdToFrameMap = getFrameMapping();
+  const auto CSIdToCallStackMap = getCallStackMapping();
+  for (const auto &I : IdToFrameMap) {
+    Writer.addMemProfFrame(I.first, I.getSecond(), Err);
+  }
+  for (const auto &I : CSIdToCallStackMap) {
+    Writer.addMemProfCallStack(I.first, I.getSecond(), Err);
+  }
+  Writer.addMemProfRecord(/*Id=*/0x9999, IndexedMR);
+
+  auto Profile = Writer.writeBuffer();
+  readProfile(std::move(Profile));
+
+  auto RecordOr = Reader->getMemProfRecord(0x9999);
+  ASSERT_THAT_ERROR(RecordOr.takeError(), Succeeded());
+  const memprof::MemProfRecord &Record = RecordOr.get();
+
+  std::optional<memprof::FrameId> LastUnmappedFrameId;
+  auto IdToFrameCallback = [&](const memprof::FrameId Id) {
+    auto Iter = IdToFrameMap.find(Id);
+    if (Iter == IdToFrameMap.end()) {
+      LastUnmappedFrameId = Id;
+      return memprof::Frame(0, 0, 0, false);
+    }
+    return Iter->second;
+  };
+
+  std::optional<::llvm::memprof::CallStackId> LastUnmappedCSId;
+  auto CSIdToCallStackCallback = [&](::llvm::memprof::CallStackId CSId) {
+    llvm::SmallVector<memprof::Frame> Frames;
+    auto CSIter = CSIdToCallStackMap.find(CSId);
+    if (CSIter == CSIdToCallStackMap.end()) {
+      LastUnmappedCSId = CSId;
+    } else {
+      const ::llvm::SmallVector<::llvm::memprof::FrameId> &CS =
+          CSIter->getSecond();
+      Frames.reserve(CS.size());
+      for (::llvm::memprof::FrameId Id : CS)
+        Frames.push_back(IdToFrameCallback(Id));
+    }
+    return Frames;
+  };
+
+  const ::llvm::memprof::MemProfRecord WantRecord =
+      IndexedMR.toMemProfRecord(CSIdToCallStackCallback);
+  ASSERT_FALSE(LastUnmappedFrameId.has_value())
----------------
snehasish wrote:

`ASSERT_EQ(LastUnmappedFrameId, std::nullopt) << "could not map frame id: " << *LastUnmappedFrameId;` seems a little easier to read so that we don't have to think about the inversion of `has_value`.

https://github.com/llvm/llvm-project/pull/89100