wangtao
/
llvm-project
forked from OSchip/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Don't read all of the records in the PCH file's preprocessor block, 

most of which are ignored. Instead, move the __COUNTER__ value out to
a PCH-level record (since it is handled eagerly) and move the header
file information into the SourceManager block (which is also,
currently, loaded eagerly).

This results in another 17% performance improvement in the
Cocoa-prefixed "Hello, World" with PCH.

llvm-svn: 70097
This commit is contained in:
Douglas Gregor 2009-04-26 00:07:37 +00:00
parent ab2784f2c1
commit eda6a89c4e
5 changed files with 59 additions and 125 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

21
clang/include/clang/Frontend/PCHBitCodes.h
View File

@ -169,7 +169,11 @@ namespace clang {
SELECTOR_OFFSETS = 12,
/// \brief Record code for the Objective-C method pool,
METHOD_POOL = 13
METHOD_POOL = 13,
/// \brief The value of the next __COUNTER__ to dispense.
/// [PP_COUNTER_VALUE, Val]
PP_COUNTER_VALUE = 14
};
/// \brief Record types used within a source manager block.
@ -189,7 +193,10 @@ namespace clang {
SM_SLOC_INSTANTIATION_ENTRY = 4,
/// \brief Describes the SourceManager's line table, with
/// information about #line directives.
SM_LINE_TABLE = 5
SM_LINE_TABLE = 5,
/// \brief Describes one header file info [isImport, DirInfo, NumIncludes]
/// ControllingMacro is optional.
SM_HEADER_FILE_INFO = 6
};
/// \brief Record types used within a preprocessor block.
@ -208,15 +215,7 @@ namespace clang {
/// \brief Describes one token.
/// [PP_TOKEN, SLoc, Length, IdentInfoID, Kind, Flags]
PP_TOKEN = 3,
/// \brief The value of the next __COUNTER__ to dispense.
/// [PP_COUNTER_VALUE, Val]
PP_COUNTER_VALUE = 4,
/// \brief Describes one header file info [isImport, DirInfo, NumIncludes]
/// ControlloingMacro is optional.
PP_HEADER_FILE_INFO = 5
PP_TOKEN = 3
};
/// \defgroup PCHAST Precompiled header AST constants

3
clang/include/clang/Frontend/PCHReader.h
View File

@ -245,12 +245,11 @@ private:
/// Objective-C protocols.
llvm::SmallVector<Decl *, 16> InterestingDecls;
PCHReadResult ReadPCHBlock(uint64_t &PreprocessorBlockOffset);
PCHReadResult ReadPCHBlock();
bool CheckPredefinesBuffer(const char *PCHPredef,
unsigned PCHPredefLen,
FileID PCHBufferID);
PCHReadResult ReadSourceManagerBlock();
bool ReadPreprocessorBlock();
bool ParseLanguageOptions(const llvm::SmallVectorImpl<uint64_t> &Record);
QualType ReadTypeRecord(uint64_t Offset);

3
clang/include/clang/Frontend/PCHWriter.h
View File

@ -156,7 +156,8 @@ private:
void WriteTargetTriple(const TargetInfo &Target);
void WriteLanguageOptions(const LangOptions &LangOpts);
void WriteSourceManagerBlock(SourceManager &SourceMgr);
void WriteSourceManagerBlock(SourceManager &SourceMgr,
const Preprocessor &PP);
void WritePreprocessor(const Preprocessor &PP);
void WriteType(const Type *T);
void WriteTypesBlock(ASTContext &Context);

102
clang/lib/Frontend/PCHReader.cpp
View File

@ -1473,6 +1473,7 @@ PCHReader::PCHReadResult PCHReader::ReadSourceManagerBlock() {
SourceManager &SourceMgr = Context.getSourceManager();
RecordData Record;
unsigned NumHeaderInfos = 0;
while (true) {
unsigned Code = Stream.ReadCode();
if (Code == llvm::bitc::END_BLOCK) {
@ -1557,6 +1558,16 @@ PCHReader::PCHReadResult PCHReader::ReadSourceManagerBlock() {
if (ParseLineTable(SourceMgr, Record))
return Failure;
break;
case pch::SM_HEADER_FILE_INFO: {
HeaderFileInfo HFI;
HFI.isImport = Record[0];
HFI.DirInfo = Record[1];
HFI.NumIncludes = Record[2];
HFI.ControllingMacroID = Record[3];
PP.getHeaderSearchInfo().setHeaderFileInfoForUID(HFI, NumHeaderInfos++);
break;
}
}
}
}
@ -1597,10 +1608,6 @@ void PCHReader::ReadMacroRecord(uint64_t Offset) {
pch::PreprocessorRecordTypes RecType =
(pch::PreprocessorRecordTypes)Stream.ReadRecord(Code, Record);
switch (RecType) {
case pch::PP_COUNTER_VALUE:
// Skip this record.
break;
case pch::PP_MACRO_OBJECT_LIKE:
case pch::PP_MACRO_FUNCTION_LIKE: {
// If we already have a macro, that means that we've hit the end
@ -1663,70 +1670,12 @@ void PCHReader::ReadMacroRecord(uint64_t Offset) {
Macro->AddTokenToBody(Tok);
break;
}
case pch::PP_HEADER_FILE_INFO:
break; // Already processed by ReadPreprocessorBlock().
}
}
}
bool PCHReader::ReadPreprocessorBlock() {
if (Stream.EnterSubBlock(pch::PREPROCESSOR_BLOCK_ID))
return Error("Malformed preprocessor block record");
RecordData Record;
unsigned NumHeaderInfos = 0;
while (true) {
unsigned Code = Stream.ReadCode();
switch (Code) {
case llvm::bitc::END_BLOCK:
if (Stream.ReadBlockEnd())
return Error("Error at end of preprocessor block");
return false;
case llvm::bitc::ENTER_SUBBLOCK:
// No known subblocks, always skip them.
Stream.ReadSubBlockID();
if (Stream.SkipBlock())
return Error("Malformed block record");
continue;
case llvm::bitc::DEFINE_ABBREV:
Stream.ReadAbbrevRecord();
continue;
default: break;
}
// Read a record.
Record.clear();
pch::PreprocessorRecordTypes RecType =
(pch::PreprocessorRecordTypes)Stream.ReadRecord(Code, Record);
switch (RecType) {
default: // Default behavior: ignore unknown records.
break;
case pch::PP_COUNTER_VALUE:
if (!Record.empty())
PP.setCounterValue(Record[0]);
break;
case pch::PP_MACRO_OBJECT_LIKE:
case pch::PP_MACRO_FUNCTION_LIKE:
case pch::PP_TOKEN:
break;
case pch::PP_HEADER_FILE_INFO: {
HeaderFileInfo HFI;
HFI.isImport = Record[0];
HFI.DirInfo = Record[1];
HFI.NumIncludes = Record[2];
HFI.ControllingMacroID = Record[3];
PP.getHeaderSearchInfo().setHeaderFileInfoForUID(HFI, NumHeaderInfos++);
break;
}
}
}
}
PCHReader::PCHReadResult
PCHReader::ReadPCHBlock(uint64_t &PreprocessorBlockOffset) {
PCHReader::ReadPCHBlock() {
if (Stream.EnterSubBlock(pch::PCH_BLOCK_ID)) {
Error("Malformed block record");
return Failure;
@ -1757,13 +1706,6 @@ PCHReader::ReadPCHBlock(uint64_t &PreprocessorBlockOffset) {
break;
case pch::PREPROCESSOR_BLOCK_ID:
// Skip the preprocessor block for now, but remember where it is. We
// want to read it in after the identifier table.
if (PreprocessorBlockOffset) {
Error("Multiple preprocessor blocks found.");
return Failure;
}
PreprocessorBlockOffset = Stream.GetCurrentBitNo();
if (Stream.SkipBlock()) {
Error("Malformed block record");
return Failure;
@ -1907,6 +1849,11 @@ PCHReader::ReadPCHBlock(uint64_t &PreprocessorBlockOffset) {
PCHMethodPoolLookupTrait(*this));
TotalSelectorsInMethodPool = Record[1];
break;
case pch::PP_COUNTER_VALUE:
if (!Record.empty())
PP.setCounterValue(Record[0]);
break;
}
}
Error("Premature end of bitstream");
@ -1938,10 +1885,6 @@ PCHReader::PCHReadResult PCHReader::ReadPCH(const std::string &FileName) {
return IgnorePCH;
}
// We expect a number of well-defined blocks, though we don't necessarily
// need to understand them all.
uint64_t PreprocessorBlockOffset = 0;
while (!Stream.AtEndOfStream()) {
unsigned Code = Stream.ReadCode();
@ -1961,7 +1904,7 @@ PCHReader::PCHReadResult PCHReader::ReadPCH(const std::string &FileName) {
}
break;
case pch::PCH_BLOCK_ID:
switch (ReadPCHBlock(PreprocessorBlockOffset)) {
switch (ReadPCHBlock()) {
case Success:
break;
@ -2036,15 +1979,6 @@ PCHReader::PCHReadResult PCHReader::ReadPCH(const std::string &FileName) {
if (unsigned FastEnum
= SpecialTypes[pch::SPECIAL_TYPE_OBJC_FAST_ENUMERATION_STATE])
Context.setObjCFastEnumerationStateType(GetType(FastEnum));
// If we saw the preprocessor block, read it now.
if (PreprocessorBlockOffset) {
SavedStreamPosition SavedPos(Stream);
Stream.JumpToBit(PreprocessorBlockOffset);
if (ReadPreprocessorBlock()) {
Error("Malformed preprocessor block");
return Failure;
}
}
return Success;
}

55
clang/lib/Frontend/PCHWriter.cpp
View File

@ -1359,7 +1359,8 @@ static unsigned CreateSLocInstantiationAbbrev(llvm::BitstreamWriter &Stream) {
/// entries for files that we actually need. In the common case (no
/// errors), we probably won't have to create file entries for any of
/// the files in the AST.
void PCHWriter::WriteSourceManagerBlock(SourceManager &SourceMgr) {
void PCHWriter::WriteSourceManagerBlock(SourceManager &SourceMgr,
const Preprocessor &PP) {
// Enter the source manager block.
Stream.EnterSubblock(pch::SOURCE_MANAGER_BLOCK_ID, 3);
@ -1481,6 +1482,22 @@ void PCHWriter::WriteSourceManagerBlock(SourceManager &SourceMgr) {
}
}
// Loop over all the header files.
HeaderSearch &HS = PP.getHeaderSearchInfo();
for (HeaderSearch::header_file_iterator I = HS.header_file_begin(),
E = HS.header_file_end();
I != E; ++I) {
Record.push_back(I->isImport);
Record.push_back(I->DirInfo);
Record.push_back(I->NumIncludes);
if (I->ControllingMacro)
AddIdentifierRef(I->ControllingMacro, Record);
else
Record.push_back(0);
Stream.EmitRecord(pch::SM_HEADER_FILE_INFO, Record);
Record.clear();
}
Stream.ExitBlock();
}
@ -1488,14 +1505,6 @@ void PCHWriter::WriteSourceManagerBlock(SourceManager &SourceMgr) {
/// preprocessor.
///
void PCHWriter::WritePreprocessor(const Preprocessor &PP) {
// Enter the preprocessor block.
Stream.EnterSubblock(pch::PREPROCESSOR_BLOCK_ID, 2);
// If the PCH file contains __DATE__ or __TIME__ emit a warning about this.
// FIXME: use diagnostics subsystem for localization etc.
if (PP.SawDateOrTime())
fprintf(stderr, "warning: precompiled header used __DATE__ or __TIME__.\n");
RecordData Record;
// If the preprocessor __COUNTER__ value has been bumped, remember it.
@ -1503,8 +1512,16 @@ void PCHWriter::WritePreprocessor(const Preprocessor &PP) {
Record.push_back(PP.getCounterValue());
Stream.EmitRecord(pch::PP_COUNTER_VALUE, Record);
Record.clear();
}
}
// Enter the preprocessor block.
Stream.EnterSubblock(pch::PREPROCESSOR_BLOCK_ID, 2);
// If the PCH file contains __DATE__ or __TIME__ emit a warning about this.
// FIXME: use diagnostics subsystem for localization etc.
if (PP.SawDateOrTime())
fprintf(stderr, "warning: precompiled header used __DATE__ or __TIME__.\n");
// Loop over all the macro definitions that are live at the end of the file,
// emitting each to the PP section.
for (Preprocessor::macro_iterator I = PP.macro_begin(), E = PP.macro_end();
@ -1564,22 +1581,6 @@ void PCHWriter::WritePreprocessor(const Preprocessor &PP) {
}
++NumMacros;
}
// Loop over all the header files.
HeaderSearch &HS = PP.getHeaderSearchInfo();
for (HeaderSearch::header_file_iterator I = HS.header_file_begin(),
E = HS.header_file_end();
I != E; ++I) {
Record.push_back(I->isImport);
Record.push_back(I->DirInfo);
Record.push_back(I->NumIncludes);
if (I->ControllingMacro)
AddIdentifierRef(I->ControllingMacro, Record);
else
Record.push_back(0);
Stream.EmitRecord(pch::PP_HEADER_FILE_INFO, Record);
Record.clear();
}
Stream.ExitBlock();
}
@ -2365,7 +2366,7 @@ void PCHWriter::WritePCH(Sema &SemaRef) {
Stream.EnterSubblock(pch::PCH_BLOCK_ID, 4);
WriteTargetTriple(Context.Target);
WriteLanguageOptions(Context.getLangOptions());
WriteSourceManagerBlock(Context.getSourceManager());
WriteSourceManagerBlock(Context.getSourceManager(), PP);
WritePreprocessor(PP);
WriteTypesBlock(Context);
WriteDeclsBlock(Context);