llvm::ErrorOr<SerializedDiagnosticReader::Cursor>
SerializedDiagnosticReader::skipUntilRecordOrBlock(
llvm::BitstreamCursor &Stream, unsigned &BlockOrRecordID) {
BlockOrRecordID = 0;
while (!Stream.AtEndOfStream()) {
unsigned Code = Stream.ReadCode();
switch ((llvm::bitc::FixedAbbrevIDs)Code) {
case llvm::bitc::ENTER_SUBBLOCK:
BlockOrRecordID = Stream.ReadSubBlockID();
return Cursor::BlockBegin;
case llvm::bitc::END_BLOCK:
if (Stream.ReadBlockEnd())
return SDError::InvalidDiagnostics;
return Cursor::BlockEnd;
case llvm::bitc::DEFINE_ABBREV:
Stream.ReadAbbrevRecord();
continue;
case llvm::bitc::UNABBREV_RECORD:
return SDError::UnsupportedConstruct;
default:
// We found a record.
BlockOrRecordID = Code;
return Cursor::Record;
}
}
return SDError::InvalidDiagnostics;
}
static bool checkModuleDocSignature(llvm::BitstreamCursor &cursor) {
for (unsigned char byte : MODULE_DOC_SIGNATURE)
if (cursor.AtEndOfStream() || cursor.Read(8) != byte)
return false;
return true;
}
StreamResult DiagLoader::readToNextRecordOrBlock(llvm::BitstreamCursor &Stream,
llvm::StringRef errorContext,
unsigned &blockOrRecordID,
bool atTopLevel) {
blockOrRecordID = 0;
while (!Stream.AtEndOfStream()) {
unsigned Code = Stream.ReadCode();
// Handle the top-level specially.
if (atTopLevel) {
if (Code == llvm::bitc::ENTER_SUBBLOCK) {
unsigned BlockID = Stream.ReadSubBlockID();
if (BlockID == llvm::bitc::BLOCKINFO_BLOCK_ID) {
if (Stream.ReadBlockInfoBlock()) {
reportInvalidFile("Malformed BlockInfoBlock in diagnostics file");
return Read_Failure;
}
continue;
}
blockOrRecordID = BlockID;
return Read_BlockBegin;
}
reportInvalidFile("Only blocks can appear at the top of a "
"diagnostic file");
return Read_Failure;
}
switch ((llvm::bitc::FixedAbbrevIDs)Code) {
case llvm::bitc::ENTER_SUBBLOCK:
blockOrRecordID = Stream.ReadSubBlockID();
return Read_BlockBegin;
case llvm::bitc::END_BLOCK:
if (Stream.ReadBlockEnd()) {
reportInvalidFile("Cannot read end of block");
return Read_Failure;
}
return Read_BlockEnd;
case llvm::bitc::DEFINE_ABBREV:
Stream.ReadAbbrevRecord();
continue;
case llvm::bitc::UNABBREV_RECORD:
reportInvalidFile("Diagnostics file should have no unabbreviated "
"records");
return Read_Failure;
default:
// We found a record.
blockOrRecordID = Code;
return Read_Record;
}
}
if (atTopLevel)
return Read_EndOfStream;
reportInvalidFile(Twine("Premature end of diagnostics file within ").str() +
errorContext.str());
return Read_Failure;
}