1 files changed, 110 insertions, 0 deletions
diff --git a/lib/DebugInfo/PDB/Native/TpiHashing.cpp b/lib/DebugInfo/PDB/Native/TpiHashing.cpp
new file mode 100644
index 0000000000000..16904a5a27ed3
--- /dev/null
+++ b/lib/DebugInfo/PDB/Native/TpiHashing.cpp
@@ -0,0 +1,110 @@
+//===- TpiHashing.cpp -----------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/DebugInfo/PDB/Native/TpiHashing.h"
+
+#include "llvm/DebugInfo/PDB/Native/Hash.h"
+#include "llvm/DebugInfo/PDB/Native/RawError.h"
+
+using namespace llvm;
+using namespace llvm::codeview;
+using namespace llvm::pdb;
+
+// Corresponds to `fUDTAnon`.
+template <typename T> static bool isAnonymous(T &Rec) {
+  StringRef Name = Rec.getName();
+  return Name == "<unnamed-tag>" || Name == "__unnamed" ||
+         Name.endswith("::<unnamed-tag>") || Name.endswith("::__unnamed");
+}
+
+// Computes a hash for a given TPI record.
+template <typename T>
+static uint32_t getTpiHash(T &Rec, ArrayRef<uint8_t> FullRecord) {
+  auto Opts = static_cast<uint16_t>(Rec.getOptions());
+
+  bool ForwardRef =
+      Opts & static_cast<uint16_t>(ClassOptions::ForwardReference);
+  bool Scoped = Opts & static_cast<uint16_t>(ClassOptions::Scoped);
+  bool UniqueName = Opts & static_cast<uint16_t>(ClassOptions::HasUniqueName);
+  bool IsAnon = UniqueName && isAnonymous(Rec);
+
+  if (!ForwardRef && !Scoped && !IsAnon)
+    return hashStringV1(Rec.getName());
+  if (!ForwardRef && UniqueName && !IsAnon)
+    return hashStringV1(Rec.getUniqueName());
+  return hashBufferV8(FullRecord);
+}
+
+template <typename T> static uint32_t getSourceLineHash(T &Rec) {
+  char Buf[4];
+  support::endian::write32le(Buf, Rec.getUDT().getIndex());
+  return hashStringV1(StringRef(Buf, 4));
+}
+
+void TpiHashUpdater::visitKnownRecordImpl(CVType &CVR,
+                                          UdtSourceLineRecord &Rec) {
+  CVR.Hash = getSourceLineHash(Rec);
+}
+
+void TpiHashUpdater::visitKnownRecordImpl(CVType &CVR,
+                                          UdtModSourceLineRecord &Rec) {
+  CVR.Hash = getSourceLineHash(Rec);
+}
+
+void TpiHashUpdater::visitKnownRecordImpl(CVType &CVR, ClassRecord &Rec) {
+  CVR.Hash = getTpiHash(Rec, CVR.data());
+}
+
+void TpiHashUpdater::visitKnownRecordImpl(CVType &CVR, EnumRecord &Rec) {
+  CVR.Hash = getTpiHash(Rec, CVR.data());
+}
+
+void TpiHashUpdater::visitKnownRecordImpl(CVType &CVR, UnionRecord &Rec) {
+  CVR.Hash = getTpiHash(Rec, CVR.data());
+}
+
+Error TpiHashVerifier::visitKnownRecord(CVType &CVR, UdtSourceLineRecord &Rec) {
+  return verifySourceLine(Rec.getUDT());
+}
+
+Error TpiHashVerifier::visitKnownRecord(CVType &CVR,
+                                        UdtModSourceLineRecord &Rec) {
+  return verifySourceLine(Rec.getUDT());
+}
+
+Error TpiHashVerifier::visitKnownRecord(CVType &CVR, ClassRecord &Rec) {
+  if (getTpiHash(Rec, CVR.data()) % NumHashBuckets != HashValues[Index])
+    return errorInvalidHash();
+  return Error::success();
+}
+Error TpiHashVerifier::visitKnownRecord(CVType &CVR, EnumRecord &Rec) {
+  if (getTpiHash(Rec, CVR.data()) % NumHashBuckets != HashValues[Index])
+    return errorInvalidHash();
+  return Error::success();
+}
+Error TpiHashVerifier::visitKnownRecord(CVType &CVR, UnionRecord &Rec) {
+  if (getTpiHash(Rec, CVR.data()) % NumHashBuckets != HashValues[Index])
+    return errorInvalidHash();
+  return Error::success();
+}
+
+Error TpiHashVerifier::verifySourceLine(codeview::TypeIndex TI) {
+  char Buf[4];
+  support::endian::write32le(Buf, TI.getIndex());
+  uint32_t Hash = hashStringV1(StringRef(Buf, 4));
+  if (Hash % NumHashBuckets != HashValues[Index])
+    return errorInvalidHash();
+  return Error::success();
+}
+
+Error TpiHashVerifier::visitTypeBegin(CVType &Rec) {
+  ++Index;
+  RawRecord = Rec;
+  return Error::success();
+}