1 files changed, 201 insertions, 0 deletions
diff --git a/llvm/lib/Transforms/Utils/ImportedFunctionsInliningStatistics.cpp b/llvm/lib/Transforms/Utils/ImportedFunctionsInliningStatistics.cpp
new file mode 100644
index 00000000000..7f27e96602c
--- /dev/null
+++ b/llvm/lib/Transforms/Utils/ImportedFunctionsInliningStatistics.cpp
@@ -0,0 +1,201 @@
+//===-- ImportedFunctionsInliningStats.cpp ----------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+// Generating inliner statistics for imported functions, mostly useful for
+// ThinLTO.
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Transforms/Utils/ImportedFunctionsInliningStatistics.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/IR/Function.h"
+#include "llvm/IR/Module.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/raw_ostream.h"
+#include <algorithm>
+#include <iomanip>
+#include <sstream>
+using namespace llvm;
+
+ImportedFunctionsInliningStatistics::InlineGraphNode &
+ImportedFunctionsInliningStatistics::createInlineGraphNode(const Function &F) {
+
+  auto &ValueLookup = NodesMap[F.getName()];
+  if (!ValueLookup) {
+    ValueLookup = llvm::make_unique<InlineGraphNode>();
+    ValueLookup->Imported = F.getMetadata("thinlto_src_module") != nullptr;
+  }
+  return *ValueLookup;
+}
+
+void ImportedFunctionsInliningStatistics::recordInline(const Function &Caller,
+                                                       const Function &Callee) {
+
+  InlineGraphNode &CallerNode = createInlineGraphNode(Caller);
+  InlineGraphNode &CalleeNode = createInlineGraphNode(Callee);
+  CalleeNode.NumberOfInlines++;
+
+  if (!CallerNode.Imported && !CalleeNode.Imported) {
+    // Direct inline from not imported callee to not imported caller, so we
+    // don't have to add this to graph. It might be very helpful if you wanna
+    // get the inliner statistics in compile step where there are no imported
+    // functions. In this case the graph would be empty.
+    CalleeNode.NumberOfRealInlines++;
+    return;
+  }
+
+  CallerNode.InlinedCallees.push_back(&CalleeNode);
+  if (!CallerNode.Imported)
+    // Save Caller as a starting node for traversal.
+    NonImportedCallers.push_back(Caller.getName());
+}
+
+void ImportedFunctionsInliningStatistics::setModuleInfo(const Module &M) {
+  ModuleName = M.getName();
+  for (const auto &F : M.functions()) {
+    AllFunctions++;
+    ImportedFunctions += int(F.getMetadata("thinlto_src_module") != nullptr);
+  }
+}
+static std::string getStatString(const char *Msg, int32_t Fraction, int32_t All,
+                                 const char *PercentageOfMsg,
+                                 bool LineEnd = true) {
+  double Result = 0;
+  if (All != 0)
+    Result = 100 * static_cast<double>(Fraction) / All;
+
+  std::stringstream Str;
+  Str << std::setprecision(4) << Msg << ": " << Fraction << " [" << Result
+      << "% of " << PercentageOfMsg << "]";
+  if (LineEnd)
+    Str << "\n";
+  return Str.str();
+}
+
+void ImportedFunctionsInliningStatistics::dump(const bool Verbose) {
+  calculateRealInlines();
+  NonImportedCallers.clear();
+
+  int32_t InlinedImportedFunctionsCount = 0;
+  int32_t InlinedNotImportedFunctionsCount = 0;
+
+  int32_t InlinedImportedFunctionsToImportingModuleCount = 0;
+  int32_t InlinedNotImportedFunctionsToImportingModuleCount = 0;
+
+  const auto SortedNodes = getSortedNodes();
+  std::string Out;
+  Out.reserve(5000);
+  raw_string_ostream Ostream(Out);
+
+  Ostream << "------- Dumping inliner stats for [" << ModuleName
+          << "] -------\n";
+
+  if (Verbose)
+    Ostream << "-- List of inlined functions:\n";
+
+  for (const auto &Node : SortedNodes) {
+    assert(Node.second->NumberOfInlines >= Node.second->NumberOfRealInlines);
+    if (Node.second->NumberOfInlines == 0)
+      continue;
+
+    if (Node.second->Imported) {
+      InlinedImportedFunctionsCount++;
+      InlinedImportedFunctionsToImportingModuleCount +=
+          int(Node.second->NumberOfRealInlines > 0);
+    } else {
+      InlinedNotImportedFunctionsCount++;
+      InlinedNotImportedFunctionsToImportingModuleCount +=
+          int(Node.second->NumberOfRealInlines > 0);
+    }
+
+    if (Verbose)
+      Ostream << "Inlined "
+              << (Node.second->Imported ? "imported " : "not imported ")
+              << "function [" << Node.first << "]"
+              << ": #inlines = " << Node.second->NumberOfInlines
+              << ", #inlines_to_importing_module = "
+              << Node.second->NumberOfRealInlines << "\n";
+  }
+
+  auto InlinedFunctionsCount =
+      InlinedImportedFunctionsCount + InlinedNotImportedFunctionsCount;
+  auto NotImportedFuncCount = AllFunctions - ImportedFunctions;
+  auto ImportedNotInlinedIntoModule =
+      ImportedFunctions - InlinedImportedFunctionsToImportingModuleCount;
+
+  Ostream << "-- Summary:\n"
+          << "All functions: " << AllFunctions
+          << ", imported functions: " << ImportedFunctions << "\n"
+          << getStatString("inlined functions", InlinedFunctionsCount,
+                           AllFunctions, "all functions")
+          << getStatString("imported functions inlined anywhere",
+                           InlinedImportedFunctionsCount, ImportedFunctions,
+                           "imported functions")
+          << getStatString("imported functions inlined into importing module",
+                           InlinedImportedFunctionsToImportingModuleCount,
+                           ImportedFunctions, "imported functions",
+                           /*LineEnd=*/false)
+          << getStatString(", remaining", ImportedNotInlinedIntoModule,
+                           ImportedFunctions, "imported functions")
+          << getStatString("non-imported functions inlined anywhere",
+                           InlinedNotImportedFunctionsCount,
+                           NotImportedFuncCount, "non-imported functions")
+          << getStatString(
+                 "non-imported functions inlined into importing module",
+                 InlinedNotImportedFunctionsToImportingModuleCount,
+                 NotImportedFuncCount, "non-imported functions");
+  Ostream.flush();
+  dbgs() << Out;
+}
+
+void ImportedFunctionsInliningStatistics::calculateRealInlines() {
+  // Removing duplicated Callers.
+  std::sort(NonImportedCallers.begin(), NonImportedCallers.end());
+  NonImportedCallers.erase(
+      std::unique(NonImportedCallers.begin(), NonImportedCallers.end()),
+      NonImportedCallers.end());
+
+  for (const auto &Name : NonImportedCallers) {
+    auto &Node = *NodesMap[Name];
+    if (!Node.Visited)
+      dfs(Node);
+  }
+}
+
+void ImportedFunctionsInliningStatistics::dfs(InlineGraphNode &GraphNode) {
+  assert(!GraphNode.Visited);
+  GraphNode.Visited = true;
+  for (auto *const InlinedFunctionNode : GraphNode.InlinedCallees) {
+    InlinedFunctionNode->NumberOfRealInlines++;
+    if (!InlinedFunctionNode->Visited)
+      dfs(*InlinedFunctionNode);
+  }
+}
+
+ImportedFunctionsInliningStatistics::SortedNodesTy
+ImportedFunctionsInliningStatistics::getSortedNodes() {
+  SortedNodesTy SortedNodes;
+  SortedNodes.reserve(NodesMap.size());
+
+  for (auto &&Node : NodesMap)
+    SortedNodes.emplace_back(Node.first, std::move(Node.second));
+
+  NodesMap.clear(); // We don't want to leave nullptrs.
+
+  std::sort(
+      SortedNodes.begin(), SortedNodes.end(),
+      [&](const SortedNodesTy::value_type &Lhs,
+          const SortedNodesTy::value_type &Rhs) {
+        if (Lhs.second->NumberOfInlines != Rhs.second->NumberOfInlines)
+          return Lhs.second->NumberOfInlines > Rhs.second->NumberOfInlines;
+        if (Lhs.second->NumberOfRealInlines != Rhs.second->NumberOfRealInlines)
+          return Lhs.second->NumberOfRealInlines >
+                 Rhs.second->NumberOfRealInlines;
+        return Lhs.first < Rhs.first;
+      });
+  return SortedNodes;
+}