1 files changed, 172 insertions, 0 deletions
diff --git a/llvm/lib/CodeGen/GCMetadata.cpp b/llvm/lib/CodeGen/GCMetadata.cpp
new file mode 100644
index 000000000000..c1d22ef89195
--- /dev/null
+++ b/llvm/lib/CodeGen/GCMetadata.cpp
@@ -0,0 +1,172 @@
+//===-- GCMetadata.cpp - Garbage collector metadata -----------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the GCFunctionInfo class and GCModuleInfo pass.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/CodeGen/GCMetadata.h"
+#include "llvm/CodeGen/GCStrategy.h"
+#include "llvm/CodeGen/Passes.h"
+#include "llvm/IR/Function.h"
+#include "llvm/MC/MCSymbol.h"
+#include "llvm/Pass.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/raw_ostream.h"
+#include <algorithm>
+#include <cassert>
+#include <memory>
+#include <string>
+
+using namespace llvm;
+
+namespace {
+
+class Printer : public FunctionPass {
+  static char ID;
+
+  raw_ostream &OS;
+
+public:
+  explicit Printer(raw_ostream &OS) : FunctionPass(ID), OS(OS) {}
+
+  StringRef getPassName() const override;
+  void getAnalysisUsage(AnalysisUsage &AU) const override;
+
+  bool runOnFunction(Function &F) override;
+  bool doFinalization(Module &M) override;
+};
+
+} // end anonymous namespace
+
+INITIALIZE_PASS(GCModuleInfo, "collector-metadata",
+                "Create Garbage Collector Module Metadata", false, false)
+
+// -----------------------------------------------------------------------------
+
+GCFunctionInfo::GCFunctionInfo(const Function &F, GCStrategy &S)
+    : F(F), S(S), FrameSize(~0LL) {}
+
+GCFunctionInfo::~GCFunctionInfo() = default;
+
+// -----------------------------------------------------------------------------
+
+char GCModuleInfo::ID = 0;
+
+GCModuleInfo::GCModuleInfo() : ImmutablePass(ID) {
+  initializeGCModuleInfoPass(*PassRegistry::getPassRegistry());
+}
+
+GCFunctionInfo &GCModuleInfo::getFunctionInfo(const Function &F) {
+  assert(!F.isDeclaration() && "Can only get GCFunctionInfo for a definition!");
+  assert(F.hasGC());
+
+  finfo_map_type::iterator I = FInfoMap.find(&F);
+  if (I != FInfoMap.end())
+    return *I->second;
+
+  GCStrategy *S = getGCStrategy(F.getGC());
+  Functions.push_back(std::make_unique<GCFunctionInfo>(F, *S));
+  GCFunctionInfo *GFI = Functions.back().get();
+  FInfoMap[&F] = GFI;
+  return *GFI;
+}
+
+void GCModuleInfo::clear() {
+  Functions.clear();
+  FInfoMap.clear();
+  GCStrategyList.clear();
+}
+
+// -----------------------------------------------------------------------------
+
+char Printer::ID = 0;
+
+FunctionPass *llvm::createGCInfoPrinter(raw_ostream &OS) {
+  return new Printer(OS);
+}
+
+StringRef Printer::getPassName() const {
+  return "Print Garbage Collector Information";
+}
+
+void Printer::getAnalysisUsage(AnalysisUsage &AU) const {
+  FunctionPass::getAnalysisUsage(AU);
+  AU.setPreservesAll();
+  AU.addRequired<GCModuleInfo>();
+}
+
+bool Printer::runOnFunction(Function &F) {
+  if (F.hasGC())
+    return false;
+
+  GCFunctionInfo *FD = &getAnalysis<GCModuleInfo>().getFunctionInfo(F);
+
+  OS << "GC roots for " << FD->getFunction().getName() << ":\n";
+  for (GCFunctionInfo::roots_iterator RI = FD->roots_begin(),
+                                      RE = FD->roots_end();
+       RI != RE; ++RI)
+    OS << "\t" << RI->Num << "\t" << RI->StackOffset << "[sp]\n";
+
+  OS << "GC safe points for " << FD->getFunction().getName() << ":\n";
+  for (GCFunctionInfo::iterator PI = FD->begin(), PE = FD->end(); PI != PE;
+       ++PI) {
+
+    OS << "\t" << PI->Label->getName() << ": " << "post-call"
+       << ", live = {";
+
+    for (GCFunctionInfo::live_iterator RI = FD->live_begin(PI),
+                                       RE = FD->live_end(PI);
+         ;) {
+      OS << " " << RI->Num;
+      if (++RI == RE)
+        break;
+      OS << ",";
+    }
+
+    OS << " }\n";
+  }
+
+  return false;
+}
+
+bool Printer::doFinalization(Module &M) {
+  GCModuleInfo *GMI = getAnalysisIfAvailable<GCModuleInfo>();
+  assert(GMI && "Printer didn't require GCModuleInfo?!");
+  GMI->clear();
+  return false;
+}
+
+GCStrategy *GCModuleInfo::getGCStrategy(const StringRef Name) {
+  // TODO: Arguably, just doing a linear search would be faster for small N
+  auto NMI = GCStrategyMap.find(Name);
+  if (NMI != GCStrategyMap.end())
+    return NMI->getValue();
+
+  for (auto& Entry : GCRegistry::entries()) {
+    if (Name == Entry.getName()) {
+      std::unique_ptr<GCStrategy> S = Entry.instantiate();
+      S->Name = Name;
+      GCStrategyMap[Name] = S.get();
+      GCStrategyList.push_back(std::move(S));
+      return GCStrategyList.back().get();
+    }
+  }
+
+  if (GCRegistry::begin() == GCRegistry::end()) {
+    // In normal operation, the registry should not be empty.  There should
+    // be the builtin GCs if nothing else.  The most likely scenario here is
+    // that we got here without running the initializers used by the Registry
+    // itself and it's registration mechanism.
+    const std::string error = ("unsupported GC: " + Name).str() +
+      " (did you remember to link and initialize the CodeGen library?)";
+    report_fatal_error(error);
+  } else
+    report_fatal_error(std::string("unsupported GC: ") + Name);
+}