//
//===----------------------------------------------------------------------===//
-#ifndef BITSTREAM_WRITER_H
-#define BITSTREAM_WRITER_H
+#ifndef LLVM_BITCODE_BITSTREAMWRITER_H
+#define LLVM_BITCODE_BITSTREAMWRITER_H
+#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/Bitcode/BitCodes.h"
#include <vector>
namespace llvm {
class BitstreamWriter {
- std::vector<unsigned char> &Out;
+ SmallVectorImpl<char> &Out;
/// CurBit - Always between 0 and 31 inclusive, specifies the next bit to use.
unsigned CurBit;
};
std::vector<BlockInfo> BlockInfoRecords;
+ // BackpatchWord - Backpatch a 32-bit word in the output with the specified
+ // value.
+ void BackpatchWord(unsigned ByteNo, unsigned NewWord) {
+ Out[ByteNo++] = (unsigned char)(NewWord >> 0);
+ Out[ByteNo++] = (unsigned char)(NewWord >> 8);
+ Out[ByteNo++] = (unsigned char)(NewWord >> 16);
+ Out[ByteNo ] = (unsigned char)(NewWord >> 24);
+ }
+
+ void WriteByte(unsigned char Value) {
+ Out.push_back(Value);
+ }
+
+ void WriteWord(unsigned Value) {
+ unsigned char Bytes[4] = {
+ (unsigned char)(Value >> 0),
+ (unsigned char)(Value >> 8),
+ (unsigned char)(Value >> 16),
+ (unsigned char)(Value >> 24) };
+ Out.append(&Bytes[0], &Bytes[4]);
+ }
+
+ unsigned GetBufferOffset() const {
+ return Out.size();
+ }
+
+ unsigned GetWordIndex() const {
+ unsigned Offset = GetBufferOffset();
+ assert((Offset & 3) == 0 && "Not 32-bit aligned");
+ return Offset / 4;
+ }
+
public:
- explicit BitstreamWriter(std::vector<unsigned char> &O)
+ explicit BitstreamWriter(SmallVectorImpl<char> &O)
: Out(O), CurBit(0), CurValue(0), CurCodeSize(2) {}
~BitstreamWriter() {
}
}
- std::vector<unsigned char> &getBuffer() { return Out; }
-
/// \brief Retrieve the current position in the stream, in bits.
- uint64_t GetCurrentBitNo() const { return Out.size() * 8 + CurBit; }
+ uint64_t GetCurrentBitNo() const { return GetBufferOffset() * 8 + CurBit; }
//===--------------------------------------------------------------------===//
// Basic Primitives for emitting bits to the stream.
//===--------------------------------------------------------------------===//
void Emit(uint32_t Val, unsigned NumBits) {
- assert(NumBits <= 32 && "Invalid value size!");
+ assert(NumBits && NumBits <= 32 && "Invalid value size!");
assert((Val & ~(~0U >> (32-NumBits))) == 0 && "High bits set!");
CurValue |= Val << CurBit;
if (CurBit + NumBits < 32) {
}
// Add the current word.
- unsigned V = CurValue;
- Out.push_back((unsigned char)(V >> 0));
- Out.push_back((unsigned char)(V >> 8));
- Out.push_back((unsigned char)(V >> 16));
- Out.push_back((unsigned char)(V >> 24));
+ WriteWord(CurValue);
if (CurBit)
CurValue = Val >> (32-CurBit);
void FlushToWord() {
if (CurBit) {
- unsigned V = CurValue;
- Out.push_back((unsigned char)(V >> 0));
- Out.push_back((unsigned char)(V >> 8));
- Out.push_back((unsigned char)(V >> 16));
- Out.push_back((unsigned char)(V >> 24));
+ WriteWord(CurValue);
CurBit = 0;
CurValue = 0;
}
}
void EmitVBR(uint32_t Val, unsigned NumBits) {
+ assert(NumBits <= 32 && "Too many bits to emit!");
uint32_t Threshold = 1U << (NumBits-1);
// Emit the bits with VBR encoding, NumBits-1 bits at a time.
}
void EmitVBR64(uint64_t Val, unsigned NumBits) {
+ assert(NumBits <= 32 && "Too many bits to emit!");
if ((uint32_t)Val == Val)
return EmitVBR((uint32_t)Val, NumBits);
- uint64_t Threshold = 1U << (NumBits-1);
+ uint32_t Threshold = 1U << (NumBits-1);
// Emit the bits with VBR encoding, NumBits-1 bits at a time.
while (Val >= Threshold) {
Emit(Val, CurCodeSize);
}
- // BackpatchWord - Backpatch a 32-bit word in the output with the specified
- // value.
- void BackpatchWord(unsigned ByteNo, unsigned NewWord) {
- Out[ByteNo++] = (unsigned char)(NewWord >> 0);
- Out[ByteNo++] = (unsigned char)(NewWord >> 8);
- Out[ByteNo++] = (unsigned char)(NewWord >> 16);
- Out[ByteNo ] = (unsigned char)(NewWord >> 24);
- }
-
//===--------------------------------------------------------------------===//
// Block Manipulation
//===--------------------------------------------------------------------===//
EmitVBR(CodeLen, bitc::CodeLenWidth);
FlushToWord();
- unsigned BlockSizeWordLoc = static_cast<unsigned>(Out.size());
+ unsigned BlockSizeWordIndex = GetWordIndex();
unsigned OldCodeSize = CurCodeSize;
// Emit a placeholder, which will be replaced when the block is popped.
// Push the outer block's abbrev set onto the stack, start out with an
// empty abbrev set.
- BlockScope.push_back(Block(OldCodeSize, BlockSizeWordLoc/4));
+ BlockScope.push_back(Block(OldCodeSize, BlockSizeWordIndex));
BlockScope.back().PrevAbbrevs.swap(CurAbbrevs);
// If there is a blockinfo for this BlockID, add all the predefined abbrevs
FlushToWord();
// Compute the size of the block, in words, not counting the size field.
- unsigned SizeInWords= static_cast<unsigned>(Out.size())/4-B.StartSizeWord-1;
+ unsigned SizeInWords = GetWordIndex() - B.StartSizeWord - 1;
unsigned ByteNo = B.StartSizeWord*4;
// Update the block size field in the header of this sub-block.
private:
/// EmitAbbreviatedLiteral - Emit a literal value according to its abbrev
- /// record. This is a no-op, since the abbrev specifies the literal to use.
+ /// record. This is a no-op, since the abbrev specifies the literal to use.
template<typename uintty>
void EmitAbbreviatedLiteral(const BitCodeAbbrevOp &Op, uintty V) {
assert(Op.isLiteral() && "Not a literal");
assert(V == Op.getLiteralValue() &&
"Invalid abbrev for record!");
}
-
+
/// EmitAbbreviatedField - Emit a single scalar field value with the specified
/// encoding.
template<typename uintty>
void EmitAbbreviatedField(const BitCodeAbbrevOp &Op, uintty V) {
assert(!Op.isLiteral() && "Literals should use EmitAbbreviatedLiteral!");
-
+
// Encode the value as we are commanded.
switch (Op.getEncoding()) {
- default: assert(0 && "Unknown encoding!");
+ default: llvm_unreachable("Unknown encoding!");
case BitCodeAbbrevOp::Fixed:
- Emit((unsigned)V, (unsigned)Op.getEncodingData());
+ if (Op.getEncodingData())
+ Emit((unsigned)V, (unsigned)Op.getEncodingData());
break;
case BitCodeAbbrevOp::VBR:
- EmitVBR64(V, (unsigned)Op.getEncodingData());
+ if (Op.getEncodingData())
+ EmitVBR64(V, (unsigned)Op.getEncodingData());
break;
case BitCodeAbbrevOp::Char6:
Emit(BitCodeAbbrevOp::EncodeChar6((char)V), 6);
break;
}
}
-
+
/// EmitRecordWithAbbrevImpl - This is the core implementation of the record
/// emission code. If BlobData is non-null, then it specifies an array of
/// data that should be emitted as part of the Blob or Array operand that is
"Blob data and record entries specified for array!");
// Emit a vbr6 to indicate the number of elements present.
EmitVBR(static_cast<uint32_t>(BlobLen), 6);
-
+
// Emit each field.
for (unsigned i = 0; i != BlobLen; ++i)
EmitAbbreviatedField(EltEnc, (unsigned char)BlobData[i]);
-
+
// Know that blob data is consumed for assertion below.
BlobData = 0;
} else {
} else if (Op.getEncoding() == BitCodeAbbrevOp::Blob) {
// If this record has blob data, emit it, otherwise we must have record
// entries to encode this way.
-
+
// Emit a vbr6 to indicate the number of elements present.
if (BlobData) {
EmitVBR(static_cast<uint32_t>(BlobLen), 6);
} else {
EmitVBR(static_cast<uint32_t>(Vals.size()-RecordIdx), 6);
}
-
+
// Flush to a 32-bit alignment boundary.
FlushToWord();
- assert((Out.size() & 3) == 0 && "Not 32-bit aligned");
// Emit each field as a literal byte.
if (BlobData) {
for (unsigned i = 0; i != BlobLen; ++i)
- Out.push_back((unsigned char)BlobData[i]);
-
+ WriteByte((unsigned char)BlobData[i]);
+
// Know that blob data is consumed for assertion below.
BlobData = 0;
} else {
for (unsigned e = Vals.size(); RecordIdx != e; ++RecordIdx) {
assert(Vals[RecordIdx] < 256 && "Value too large to emit as blob");
- Out.push_back((unsigned char)Vals[RecordIdx]);
+ WriteByte((unsigned char)Vals[RecordIdx]);
}
}
+
// Align end to 32-bits.
- while (Out.size() & 3)
- Out.push_back(0);
-
+ while (GetBufferOffset() & 3)
+ WriteByte(0);
} else { // Single scalar field.
assert(RecordIdx < Vals.size() && "Invalid abbrev/record");
EmitAbbreviatedField(Op, Vals[RecordIdx]);
assert(BlobData == 0 &&
"Blob data specified for record that doesn't use it!");
}
-
+
public:
/// EmitRecord - Emit the specified record to the stream, using an abbrev if
// Insert the code into Vals to treat it uniformly.
Vals.insert(Vals.begin(), Code);
-
+
EmitRecordWithAbbrev(Abbrev, Vals);
}
-
+
/// EmitRecordWithAbbrev - Emit a record with the specified abbreviation.
/// Unlike EmitRecord, the code for the record should be included in Vals as
/// the first entry.
void EmitRecordWithAbbrev(unsigned Abbrev, SmallVectorImpl<uintty> &Vals) {
EmitRecordWithAbbrevImpl(Abbrev, Vals, StringRef());
}
-
+
/// EmitRecordWithBlob - Emit the specified record to the stream, using an
/// abbrev that includes a blob at the end. The blob data to emit is
/// specified by the pointer and length specified at the end. In contrast to
return EmitRecordWithAbbrevImpl(Abbrev, Vals, StringRef(ArrayData,
ArrayLen));
}
-
+
//===--------------------------------------------------------------------===//
// Abbrev Emission
//===--------------------------------------------------------------------===//
/// EnterBlockInfoBlock - Start emitting the BLOCKINFO_BLOCK.
void EnterBlockInfoBlock(unsigned CodeWidth) {
EnterSubblock(bitc::BLOCKINFO_BLOCK_ID, CodeWidth);
- BlockInfoCurBID = -1U;
+ BlockInfoCurBID = ~0U;
}
private:
/// SwitchToBlockID - If we aren't already talking about the specified block
projects / oota-llvm.git / blobdiff