Method readSignedVarInt

lib/Bytecode/Reader/BytecodeReader.cpp:118–124

Parse a signed variable length encoded integer from the byte stream. A signed varint is encoded as a normal varint with zigzag encoding applied, i.e. the low bit of the value is used to indicate the sign.

  /// signed varint is encoded as a normal varint with zigzag encoding applied,
  /// i.e. the low bit of the value is used to indicate the sign.
  LogicalResult readSignedVarInt(uint64_t &result) {
    if (failed(readVarInt(result)))
      return failure();
    // Essentially (but using unsigned): (x >> 1) ^ -(x & 1).
    result = (result >> 1) ^ (~(result & 1) + 1);
    return success();
  }

  template <typename T>
  std::enable_if_t<std::is_integral<T>::value, LogicalResult> readLE(T &value) {