forked from OSchip/llvm-project
parent
ef95321229
commit
84cf83f240
|
@ -24,17 +24,16 @@
|
|||
|
||||
namespace llvm {
|
||||
|
||||
class Deserializer;
|
||||
class Deserializer;
|
||||
|
||||
/// BitstreamReader - This class is used to read from an LLVM bitcode stream,
|
||||
/// maintaining information that is global to decoding the entire file. While
|
||||
/// a file is being read, multiple cursors can be independently advanced or
|
||||
/// skipped around within the file. These are represented by the
|
||||
/// BitstreamCursor class.
|
||||
/// This class is used to read from an LLVM bitcode stream, maintaining
|
||||
/// information that is global to decoding the entire file. While a file is
|
||||
/// being read, multiple cursors can be independently advanced or skipped around
|
||||
/// within the file. These are represented by the BitstreamCursor class.
|
||||
class BitstreamReader {
|
||||
public:
|
||||
/// BlockInfo - This contains information emitted to BLOCKINFO_BLOCK blocks.
|
||||
/// These describe abbreviations that all blocks of the specified ID inherit.
|
||||
/// This contains information emitted to BLOCKINFO_BLOCK blocks. These
|
||||
/// describe abbreviations that all blocks of the specified ID inherit.
|
||||
struct BlockInfo {
|
||||
unsigned BlockID;
|
||||
std::vector<IntrusiveRefCntPtr<BitCodeAbbrev>> Abbrevs;
|
||||
|
@ -47,9 +46,8 @@ private:
|
|||
|
||||
std::vector<BlockInfo> BlockInfoRecords;
|
||||
|
||||
/// IgnoreBlockInfoNames - This is set to true if we don't care about the
|
||||
/// block/record name information in the BlockInfo block. Only llvm-bcanalyzer
|
||||
/// uses this.
|
||||
/// This is set to true if we don't care about the block/record name
|
||||
/// information in the BlockInfo block. Only llvm-bcanalyzer uses this.
|
||||
bool IgnoreBlockInfoNames;
|
||||
|
||||
BitstreamReader(const BitstreamReader&) LLVM_DELETED_FUNCTION;
|
||||
|
@ -86,8 +84,7 @@ public:
|
|||
|
||||
StreamableMemoryObject &getBitcodeBytes() { return *BitcodeBytes; }
|
||||
|
||||
/// CollectBlockInfoNames - This is called by clients that want block/record
|
||||
/// name information.
|
||||
/// This is called by clients that want block/record name information.
|
||||
void CollectBlockInfoNames() { IgnoreBlockInfoNames = false; }
|
||||
bool isIgnoringBlockInfoNames() { return IgnoreBlockInfoNames; }
|
||||
|
||||
|
@ -95,13 +92,13 @@ public:
|
|||
// Block Manipulation
|
||||
//===--------------------------------------------------------------------===//
|
||||
|
||||
/// hasBlockInfoRecords - Return true if we've already read and processed the
|
||||
/// block info block for this Bitstream. We only process it for the first
|
||||
/// cursor that walks over it.
|
||||
/// Return true if we've already read and processed the block info block for
|
||||
/// this Bitstream. We only process it for the first cursor that walks over
|
||||
/// it.
|
||||
bool hasBlockInfoRecords() const { return !BlockInfoRecords.empty(); }
|
||||
|
||||
/// getBlockInfo - If there is block info for the specified ID, return it,
|
||||
/// otherwise return null.
|
||||
/// If there is block info for the specified ID, return it, otherwise return
|
||||
/// null.
|
||||
const BlockInfo *getBlockInfo(unsigned BlockID) const {
|
||||
// Common case, the most recent entry matches BlockID.
|
||||
if (!BlockInfoRecords.empty() && BlockInfoRecords.back().BlockID == BlockID)
|
||||
|
@ -134,21 +131,15 @@ public:
|
|||
}
|
||||
};
|
||||
|
||||
|
||||
/// BitstreamEntry - When advancing through a bitstream cursor, each advance can
|
||||
/// discover a few different kinds of entries:
|
||||
/// Error - Malformed bitcode was found.
|
||||
/// EndBlock - We've reached the end of the current block, (or the end of the
|
||||
/// file, which is treated like a series of EndBlock records.
|
||||
/// SubBlock - This is the start of a new subblock of a specific ID.
|
||||
/// Record - This is a record with a specific AbbrevID.
|
||||
///
|
||||
/// When advancing through a bitstream cursor, each advance can discover a few
|
||||
/// different kinds of entries:
|
||||
struct BitstreamEntry {
|
||||
enum {
|
||||
Error,
|
||||
EndBlock,
|
||||
SubBlock,
|
||||
Record
|
||||
Error, // Malformed bitcode was found.
|
||||
EndBlock, // We've reached the end of the current block, (or the end of the
|
||||
// file, which is treated like a series of EndBlock records.
|
||||
SubBlock, // This is the start of a new subblock of a specific ID.
|
||||
Record // This is a record with a specific AbbrevID.
|
||||
} Kind;
|
||||
|
||||
unsigned ID;
|
||||
|
@ -167,9 +158,9 @@ struct BitstreamEntry {
|
|||
}
|
||||
};
|
||||
|
||||
/// BitstreamCursor - This represents a position within a bitcode file. There
|
||||
/// may be multiple independent cursors reading within one bitstream, each
|
||||
/// maintaining their own local state.
|
||||
/// This represents a position within a bitcode file. There may be multiple
|
||||
/// independent cursors reading within one bitstream, each maintaining their own
|
||||
/// local state.
|
||||
///
|
||||
/// Unlike iterators, BitstreamCursors are heavy-weight objects that should not
|
||||
/// be passed by value.
|
||||
|
@ -178,24 +169,23 @@ class BitstreamCursor {
|
|||
BitstreamReader *BitStream;
|
||||
size_t NextChar;
|
||||
|
||||
|
||||
/// CurWord/word_t - This is the current data we have pulled from the stream
|
||||
/// but have not returned to the client. This is specifically and
|
||||
/// intentionally defined to follow the word size of the host machine for
|
||||
/// efficiency. We use word_t in places that are aware of this to make it
|
||||
/// perfectly explicit what is going on.
|
||||
/// This is the current data we have pulled from the stream but have not
|
||||
/// returned to the client. This is specifically and intentionally defined to
|
||||
/// follow the word size of the host machine for efficiency. We use word_t in
|
||||
/// places that are aware of this to make it perfectly explicit what is going
|
||||
/// on.
|
||||
typedef uint32_t word_t;
|
||||
word_t CurWord;
|
||||
|
||||
/// BitsInCurWord - This is the number of bits in CurWord that are valid. This
|
||||
/// is always from [0...31/63] inclusive (depending on word size).
|
||||
/// This is the number of bits in CurWord that are valid. This is always from
|
||||
/// [0...31/63] inclusive (depending on word size).
|
||||
unsigned BitsInCurWord;
|
||||
|
||||
// CurCodeSize - This is the declared size of code values used for the current
|
||||
// block, in bits.
|
||||
// This is the declared size of code values used for the current block, in
|
||||
// bits.
|
||||
unsigned CurCodeSize;
|
||||
|
||||
/// CurAbbrevs - Abbrevs installed at in this block.
|
||||
/// Abbrevs installed at in this block.
|
||||
std::vector<IntrusiveRefCntPtr<BitCodeAbbrev>> CurAbbrevs;
|
||||
|
||||
struct Block {
|
||||
|
@ -204,7 +194,7 @@ class BitstreamCursor {
|
|||
explicit Block(unsigned PCS) : PrevCodeSize(PCS) {}
|
||||
};
|
||||
|
||||
/// BlockScope - This tracks the codesize of parent blocks.
|
||||
/// This tracks the codesize of parent blocks.
|
||||
SmallVector<Block, 8> BlockScope;
|
||||
|
||||
|
||||
|
@ -250,10 +240,10 @@ public:
|
|||
return BitsInCurWord == 0 && isEndPos(NextChar);
|
||||
}
|
||||
|
||||
/// getAbbrevIDWidth - Return the number of bits used to encode an abbrev #.
|
||||
/// Return the number of bits used to encode an abbrev #.
|
||||
unsigned getAbbrevIDWidth() const { return CurCodeSize; }
|
||||
|
||||
/// GetCurrentBitNo - Return the bit # of the bit we are reading.
|
||||
/// Return the bit # of the bit we are reading.
|
||||
uint64_t GetCurrentBitNo() const {
|
||||
return NextChar*CHAR_BIT - BitsInCurWord;
|
||||
}
|
||||
|
@ -267,19 +257,17 @@ public:
|
|||
|
||||
/// Flags that modify the behavior of advance().
|
||||
enum {
|
||||
/// AF_DontPopBlockAtEnd - If this flag is used, the advance() method does
|
||||
/// not automatically pop the block scope when the end of a block is
|
||||
/// reached.
|
||||
/// If this flag is used, the advance() method does not automatically pop
|
||||
/// the block scope when the end of a block is reached.
|
||||
AF_DontPopBlockAtEnd = 1,
|
||||
|
||||
/// AF_DontAutoprocessAbbrevs - If this flag is used, abbrev entries are
|
||||
/// returned just like normal records.
|
||||
/// If this flag is used, abbrev entries are returned just like normal
|
||||
/// records.
|
||||
AF_DontAutoprocessAbbrevs = 2
|
||||
};
|
||||
|
||||
/// advance - Advance the current bitstream, returning the next entry in the
|
||||
/// stream.
|
||||
BitstreamEntry advance(unsigned Flags = 0) {
|
||||
/// Advance the current bitstream, returning the next entry in the stream.
|
||||
BitstreamEntry advance(unsigned Flags = 0) {
|
||||
while (1) {
|
||||
unsigned Code = ReadCode();
|
||||
if (Code == bitc::END_BLOCK) {
|
||||
|
@ -304,8 +292,8 @@ public:
|
|||
}
|
||||
}
|
||||
|
||||
/// advanceSkippingSubblocks - This is a convenience function for clients that
|
||||
/// don't expect any subblocks. This just skips over them automatically.
|
||||
/// This is a convenience function for clients that don't expect any
|
||||
/// subblocks. This just skips over them automatically.
|
||||
BitstreamEntry advanceSkippingSubblocks(unsigned Flags = 0) {
|
||||
while (1) {
|
||||
// If we found a normal entry, return it.
|
||||
|
@ -319,7 +307,7 @@ public:
|
|||
}
|
||||
}
|
||||
|
||||
/// JumpToBit - Reset the stream to the specified bit number.
|
||||
/// Reset the stream to the specified bit number.
|
||||
void JumpToBit(uint64_t BitNo) {
|
||||
uintptr_t ByteNo = uintptr_t(BitNo/8) & ~(sizeof(word_t)-1);
|
||||
unsigned WordBitNo = unsigned(BitNo & (sizeof(word_t)*8-1));
|
||||
|
@ -417,8 +405,8 @@ public:
|
|||
}
|
||||
}
|
||||
|
||||
// ReadVBR64 - Read a VBR that may have a value up to 64-bits in size. The
|
||||
// chunk size of the VBR must still be <= 32 bits though.
|
||||
// Read a VBR that may have a value up to 64-bits in size. The chunk size of
|
||||
// the VBR must still be <= 32 bits though.
|
||||
uint64_t ReadVBR64(unsigned NumBits) {
|
||||
uint32_t Piece = Read(NumBits);
|
||||
if ((Piece & (1U << (NumBits-1))) == 0)
|
||||
|
@ -461,15 +449,13 @@ public:
|
|||
// Block header:
|
||||
// [ENTER_SUBBLOCK, blockid, newcodelen, <align4bytes>, blocklen]
|
||||
|
||||
/// ReadSubBlockID - Having read the ENTER_SUBBLOCK code, read the BlockID for
|
||||
/// the block.
|
||||
/// Having read the ENTER_SUBBLOCK code, read the BlockID for the block.
|
||||
unsigned ReadSubBlockID() {
|
||||
return ReadVBR(bitc::BlockIDWidth);
|
||||
}
|
||||
|
||||
/// SkipBlock - Having read the ENTER_SUBBLOCK abbrevid and a BlockID, skip
|
||||
/// over the body of this block. If the block record is malformed, return
|
||||
/// true.
|
||||
/// Having read the ENTER_SUBBLOCK abbrevid and a BlockID, skip over the body
|
||||
/// of this block. If the block record is malformed, return true.
|
||||
bool SkipBlock() {
|
||||
// Read and ignore the codelen value. Since we are skipping this block, we
|
||||
// don't care what code widths are used inside of it.
|
||||
|
@ -487,8 +473,8 @@ public:
|
|||
return false;
|
||||
}
|
||||
|
||||
/// EnterSubBlock - Having read the ENTER_SUBBLOCK abbrevid, enter
|
||||
/// the block, and return true if the block has an error.
|
||||
/// Having read the ENTER_SUBBLOCK abbrevid, enter the block, and return true
|
||||
/// if the block has an error.
|
||||
bool EnterSubBlock(unsigned BlockID, unsigned *NumWordsP = nullptr);
|
||||
|
||||
bool ReadBlockEnd() {
|
||||
|
@ -524,14 +510,14 @@ private:
|
|||
|
||||
public:
|
||||
|
||||
/// getAbbrev - Return the abbreviation for the specified AbbrevId.
|
||||
/// Return the abbreviation for the specified AbbrevId.
|
||||
const BitCodeAbbrev *getAbbrev(unsigned AbbrevID) {
|
||||
unsigned AbbrevNo = AbbrevID-bitc::FIRST_APPLICATION_ABBREV;
|
||||
assert(AbbrevNo < CurAbbrevs.size() && "Invalid abbrev #!");
|
||||
return CurAbbrevs[AbbrevNo].get();
|
||||
}
|
||||
|
||||
/// skipRecord - Read the current record and discard it.
|
||||
/// Read the current record and discard it.
|
||||
void skipRecord(unsigned AbbrevID);
|
||||
|
||||
unsigned readRecord(unsigned AbbrevID, SmallVectorImpl<uint64_t> &Vals,
|
||||
|
|
Loading…
Reference in New Issue