#ifndef BITSTREAM_WRITER_H
#define BITSTREAM_WRITER_H
+#include "llvm/ADT/StringRef.h"
#include "llvm/Bitcode/BitCodes.h"
#include <vector>
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; }
+
//===--------------------------------------------------------------------===//
// Basic Primitives for emitting bits to the stream.
//===--------------------------------------------------------------------===//
//===--------------------------------------------------------------------===//
private:
+ /// EmitAbbreviatedLiteral - Emit a literal value according to its abbrev
+ /// 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");
+ // If the abbrev specifies the literal value to use, don't emit
+ // anything.
+ 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) {
- if (Op.isLiteral()) {
- // If the abbrev specifies the literal value to use, don't emit
- // anything.
- assert(V == Op.getLiteralValue() &&
- "Invalid abbrev for record!");
- return;
- }
-
+ assert(!Op.isLiteral() && "Literals should use EmitAbbreviatedLiteral!");
+
// Encode the value as we are commanded.
switch (Op.getEncoding()) {
default: assert(0 && "Unknown encoding!");
break;
}
}
-public:
-
- /// EmitRecord - Emit the specified record to the stream, using an abbrev if
- /// we have one to compress the output.
+
+ /// 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
+ /// known to exist at the end of the record.
template<typename uintty>
- void EmitRecord(unsigned Code, SmallVectorImpl<uintty> &Vals,
- unsigned Abbrev = 0) {
- if (Abbrev) {
- unsigned AbbrevNo = Abbrev-bitc::FIRST_APPLICATION_ABBREV;
- assert(AbbrevNo < CurAbbrevs.size() && "Invalid abbrev #!");
- BitCodeAbbrev *Abbv = CurAbbrevs[AbbrevNo];
+ void EmitRecordWithAbbrevImpl(unsigned Abbrev, SmallVectorImpl<uintty> &Vals,
+ StringRef Blob) {
+ const char *BlobData = Blob.data();
+ unsigned BlobLen = (unsigned) Blob.size();
+ unsigned AbbrevNo = Abbrev-bitc::FIRST_APPLICATION_ABBREV;
+ assert(AbbrevNo < CurAbbrevs.size() && "Invalid abbrev #!");
+ BitCodeAbbrev *Abbv = CurAbbrevs[AbbrevNo];
- EmitCode(Abbrev);
+ EmitCode(Abbrev);
- // Insert the code into Vals to treat it uniformly.
- Vals.insert(Vals.begin(), Code);
-
- unsigned RecordIdx = 0;
- for (unsigned i = 0, e = static_cast<unsigned>(Abbv->getNumOperandInfos());
- i != e; ++i) {
- const BitCodeAbbrevOp &Op = Abbv->getOperandInfo(i);
- if (Op.isLiteral() || Op.getEncoding() != BitCodeAbbrevOp::Array) {
- assert(RecordIdx < Vals.size() && "Invalid abbrev/record");
- EmitAbbreviatedField(Op, Vals[RecordIdx]);
- ++RecordIdx;
+ unsigned RecordIdx = 0;
+ for (unsigned i = 0, e = static_cast<unsigned>(Abbv->getNumOperandInfos());
+ i != e; ++i) {
+ const BitCodeAbbrevOp &Op = Abbv->getOperandInfo(i);
+ if (Op.isLiteral()) {
+ assert(RecordIdx < Vals.size() && "Invalid abbrev/record");
+ EmitAbbreviatedLiteral(Op, Vals[RecordIdx]);
+ ++RecordIdx;
+ } else if (Op.getEncoding() == BitCodeAbbrevOp::Array) {
+ // Array case.
+ assert(i+2 == e && "array op not second to last?");
+ const BitCodeAbbrevOp &EltEnc = Abbv->getOperandInfo(++i);
+
+ // If this record has blob data, emit it, otherwise we must have record
+ // entries to encode this way.
+ if (BlobData) {
+ assert(RecordIdx == Vals.size() &&
+ "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 {
- // Array case.
- assert(i+2 == e && "array op not second to last?");
- const BitCodeAbbrevOp &EltEnc = Abbv->getOperandInfo(++i);
-
// Emit a vbr6 to indicate the number of elements present.
EmitVBR(static_cast<uint32_t>(Vals.size()-RecordIdx), 6);
// Emit each field.
- for (; RecordIdx != Vals.size(); ++RecordIdx)
+ for (unsigned e = Vals.size(); RecordIdx != e; ++RecordIdx)
EmitAbbreviatedField(EltEnc, Vals[RecordIdx]);
}
+ } 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);
+ assert(RecordIdx == Vals.size() &&
+ "Blob data and record entries specified for blob operand!");
+ } 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]);
+
+ // 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]);
+ }
+ }
+ // Align end to 32-bits.
+ while (Out.size() & 3)
+ Out.push_back(0);
+
+ } else { // Single scalar field.
+ assert(RecordIdx < Vals.size() && "Invalid abbrev/record");
+ EmitAbbreviatedField(Op, Vals[RecordIdx]);
+ ++RecordIdx;
}
- assert(RecordIdx == Vals.size() && "Not all record operands emitted!");
- } else {
+ }
+ assert(RecordIdx == Vals.size() && "Not all record operands emitted!");
+ 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
+ /// we have one to compress the output.
+ template<typename uintty>
+ void EmitRecord(unsigned Code, SmallVectorImpl<uintty> &Vals,
+ unsigned Abbrev = 0) {
+ if (!Abbrev) {
// If we don't have an abbrev to use, emit this in its fully unabbreviated
// form.
EmitCode(bitc::UNABBREV_RECORD);
EmitVBR(static_cast<uint32_t>(Vals.size()), 6);
for (unsigned i = 0, e = static_cast<unsigned>(Vals.size()); i != e; ++i)
EmitVBR64(Vals[i], 6);
+ return;
}
+
+ // 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.
+ template<typename uintty>
+ 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
+ /// EmitRecord, this routine expects that the first entry in Vals is the code
+ /// of the record.
+ template<typename uintty>
+ void EmitRecordWithBlob(unsigned Abbrev, SmallVectorImpl<uintty> &Vals,
+ StringRef Blob) {
+ EmitRecordWithAbbrevImpl(Abbrev, Vals, Blob);
+ }
+ template<typename uintty>
+ void EmitRecordWithBlob(unsigned Abbrev, SmallVectorImpl<uintty> &Vals,
+ const char *BlobData, unsigned BlobLen) {
+ return EmitRecordWithAbbrevImpl(Abbrev, Vals, StringRef(BlobData, BlobLen));
}
+ /// EmitRecordWithArray - Just like EmitRecordWithBlob, works with records
+ /// that end with an array.
+ template<typename uintty>
+ void EmitRecordWithArray(unsigned Abbrev, SmallVectorImpl<uintty> &Vals,
+ StringRef Array) {
+ EmitRecordWithAbbrevImpl(Abbrev, Vals, Array);
+ }
+ template<typename uintty>
+ void EmitRecordWithArray(unsigned Abbrev, SmallVectorImpl<uintty> &Vals,
+ const char *ArrayData, unsigned ArrayLen) {
+ return EmitRecordWithAbbrevImpl(Abbrev, Vals, StringRef(ArrayData,
+ ArrayLen));
+ }
+
//===--------------------------------------------------------------------===//
// Abbrev Emission
//===--------------------------------------------------------------------===//
projects / oota-llvm.git / blobdiff