1 files changed, 71 insertions, 0 deletions
diff --git a/llvm/lib/DebugInfo/PDB/Native/HashTable.cpp b/llvm/lib/DebugInfo/PDB/Native/HashTable.cpp
new file mode 100644
index 0000000000000..dfdcdf1f4eafe
--- /dev/null
+++ b/llvm/lib/DebugInfo/PDB/Native/HashTable.cpp
@@ -0,0 +1,71 @@
+//===- HashTable.cpp - PDB Hash Table -------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/DebugInfo/PDB/Native/HashTable.h"
+#include "llvm/ADT/Optional.h"
+#include "llvm/DebugInfo/PDB/Native/RawError.h"
+#include "llvm/Support/BinaryStreamReader.h"
+#include "llvm/Support/BinaryStreamWriter.h"
+#include "llvm/Support/Error.h"
+#include "llvm/Support/MathExtras.h"
+#include <algorithm>
+#include <cassert>
+#include <cstdint>
+#include <utility>
+
+using namespace llvm;
+using namespace llvm::pdb;
+
+Error llvm::pdb::readSparseBitVector(BinaryStreamReader &Stream,
+                                     SparseBitVector<> &V) {
+  uint32_t NumWords;
+  if (auto EC = Stream.readInteger(NumWords))
+    return joinErrors(
+        std::move(EC),
+        make_error<RawError>(raw_error_code::corrupt_file,
+                             "Expected hash table number of words"));
+
+  for (uint32_t I = 0; I != NumWords; ++I) {
+    uint32_t Word;
+    if (auto EC = Stream.readInteger(Word))
+      return joinErrors(std::move(EC),
+                        make_error<RawError>(raw_error_code::corrupt_file,
+                                             "Expected hash table word"));
+    for (unsigned Idx = 0; Idx < 32; ++Idx)
+      if (Word & (1U << Idx))
+        V.set((I * 32) + Idx);
+  }
+  return Error::success();
+}
+
+Error llvm::pdb::writeSparseBitVector(BinaryStreamWriter &Writer,
+                                      SparseBitVector<> &Vec) {
+  constexpr int BitsPerWord = 8 * sizeof(uint32_t);
+
+  int ReqBits = Vec.find_last() + 1;
+  uint32_t ReqWords = alignTo(ReqBits, BitsPerWord) / BitsPerWord;
+  if (auto EC = Writer.writeInteger(ReqWords))
+    return joinErrors(
+        std::move(EC),
+        make_error<RawError>(raw_error_code::corrupt_file,
+                             "Could not write linear map number of words"));
+
+  uint32_t Idx = 0;
+  for (uint32_t I = 0; I != ReqWords; ++I) {
+    uint32_t Word = 0;
+    for (uint32_t WordIdx = 0; WordIdx < 32; ++WordIdx, ++Idx) {
+      if (Vec.test(Idx))
+        Word |= (1 << WordIdx);
+    }
+    if (auto EC = Writer.writeInteger(Word))
+      return joinErrors(std::move(EC), make_error<RawError>(
+                                           raw_error_code::corrupt_file,
+                                           "Could not write linear map word"));
+  }
+  return Error::success();
+}