[XRay] Add a BlockIndexer visitor for FDR Records.

Summary:
This change adds a `BlockIndexer` type which maintains pointers to
records that belong to the same process+thread pairs. The indexing
happens with order of appearance of records as they are visited.

This version of the indexer currently only supports FDR version 3 logs,
which contain `BufferExtent` records. We will add support for v2 and v1
logs in follow-up patches.

This is another part of D50441.

Reviewers: eizan, kpw, mboerger

Reviewed By: mboerger

Subscribers: mboerger, mgorny, hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D51673

llvm-svn: 341518

1 files changed, 83 insertions, 0 deletions

diff --git a/llvm/unittests/XRay/FDRBlockIndexerTest.cpp b/llvm/unittests/XRay/FDRBlockIndexerTest.cpp
new file mode 100644
index 00000000000..6f9d3eed33f
--- /dev/null
+++ b/llvm/unittests/XRay/FDRBlockIndexerTest.cpp
@@ -0,0 +1,83 @@
+//===- llvm/unittest/XRay/FDRTraceWriterTest.cpp ----------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+#include "llvm/XRay/BlockIndexer.h"
+#include "llvm/XRay/FDRLogBuilder.h"
+#include "llvm/XRay/FDRRecords.h"
+#include "gmock/gmock.h"
+#include "gtest/gtest.h"
+
+namespace llvm {
+namespace xray {
+namespace {
+
+using ::testing::ElementsAre;
+using ::testing::Eq;
+using ::testing::Field;
+using ::testing::Not;
+using ::testing::SizeIs;
+
+// This test ensures that we can index blocks that follow version 3 of the log
+// format.
+TEST(FDRBlockIndexerTest, IndexBlocksV3) {
+  auto Block0 = LogBuilder()
+                    .add<BufferExtents>(80)
+                    .add<NewBufferRecord>(1)
+                    .add<WallclockRecord>(1, 2)
+                    .add<PIDRecord>(1)
+                    .add<NewCPUIDRecord>(1)
+                    .add<FunctionRecord>(RecordTypes::ENTER, 1, 1)
+                    .add<FunctionRecord>(RecordTypes::EXIT, 1, 100)
+                    .consume();
+  auto Block1 = LogBuilder()
+                    .add<BufferExtents>(80)
+                    .add<NewBufferRecord>(1)
+                    .add<WallclockRecord>(1, 2)
+                    .add<PIDRecord>(1)
+                    .add<NewCPUIDRecord>(1)
+                    .add<FunctionRecord>(RecordTypes::ENTER, 1, 1)
+                    .add<FunctionRecord>(RecordTypes::EXIT, 1, 100)
+                    .consume();
+  auto Block2 = LogBuilder()
+                    .add<BufferExtents>(80)
+                    .add<NewBufferRecord>(2)
+                    .add<WallclockRecord>(1, 2)
+                    .add<PIDRecord>(1)
+                    .add<NewCPUIDRecord>(2)
+                    .add<FunctionRecord>(RecordTypes::ENTER, 1, 1)
+                    .add<FunctionRecord>(RecordTypes::EXIT, 1, 100)
+                    .consume();
+  BlockIndexer::Index Index;
+  BlockIndexer Indexer(Index);
+  // Iterate through the contrived blocks we have created above.
+  for (auto B : {std::ref(Block0), std::ref(Block1), std::ref(Block2)}) {
+    // For each record in the block, we apply the indexer.
+    for (auto &R : B.get())
+      ASSERT_FALSE(errorToBool(R->apply(Indexer)));
+    ASSERT_FALSE(errorToBool(Indexer.flush()));
+  }
+
+  ASSERT_THAT(Index.size(), Eq(2u));
+  auto T1Blocks = Index.find({1, 1});
+  ASSERT_THAT(T1Blocks, Not(Eq(Index.end())));
+
+  // Expect only six records, because we're ignoring the BufferExtents record.
+  EXPECT_THAT(T1Blocks->second,
+              ElementsAre(Field(&BlockIndexer::Block::Records, SizeIs(6u)),
+                          Field(&BlockIndexer::Block::Records, SizeIs(6u))));
+  auto T2Blocks = Index.find({1, 2});
+  ASSERT_THAT(T2Blocks, Not(Eq(Index.end())));
+  EXPECT_THAT(T2Blocks->second, ElementsAre(Field(&BlockIndexer::Block::Records,
+                                                  SizeIs(Eq(6u)))));
+}
+
+// FIXME: Support indexing V2 and V1 blocks.
+
+} // namespace
+} // namespace xray
+} // namespace llvm