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//===- BitCodes.h - Enum values for the bitstream format --------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This header defines bitstream enum values.
//
// The enum values defined in this file should be considered permanent. If
// new features are added, they should have values added at the end of the
// respective lists.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_BITSTREAM_BITCODES_H
#define LLVM_BITSTREAM_BITCODES_H
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/Bitstream/BitCodeEnums.h"
#include "llvm/Support/DataTypes.h"
#include "llvm/Support/ErrorHandling.h"
#include <cassert>
namespace llvm {
/// BitCodeAbbrevOp - This describes one or more operands in an abbreviation.
/// This is actually a union of two different things:
/// 1. It could be a literal integer value ("the operand is always 17").
/// 2. It could be an encoding specification ("this operand encoded like so").
///
class BitCodeAbbrevOp {
uint64_t Val; // A literal value or data for an encoding.
bool IsLiteral : 1; // Indicate whether this is a literal value or not.
unsigned Enc : 3; // The encoding to use.
public:
enum Encoding {
Fixed = 1, // A fixed width field, Val specifies number of bits.
VBR = 2, // A VBR field where Val specifies the width of each chunk.
Array = 3, // A sequence of fields, next field species elt encoding.
Char6 = 4, // A 6-bit fixed field which maps to [a-zA-Z0-9._].
Blob = 5 // 32-bit aligned array of 8-bit characters.
};
static bool isValidEncoding(uint64_t E) {
return E >= 1 && E <= 5;
}
explicit BitCodeAbbrevOp(uint64_t V) : Val(V), IsLiteral(true) {}
explicit BitCodeAbbrevOp(Encoding E, uint64_t Data = 0)
: Val(Data), IsLiteral(false), Enc(E) {}
bool isLiteral() const { return IsLiteral; }
bool isEncoding() const { return !IsLiteral; }
// Accessors for literals.
uint64_t getLiteralValue() const { assert(isLiteral()); return Val; }
// Accessors for encoding info.
Encoding getEncoding() const { assert(isEncoding()); return (Encoding)Enc; }
uint64_t getEncodingData() const {
assert(isEncoding() && hasEncodingData());
return Val;
}
bool hasEncodingData() const { return hasEncodingData(getEncoding()); }
static bool hasEncodingData(Encoding E) {
switch (E) {
case Fixed:
case VBR:
return true;
case Array:
case Char6:
case Blob:
return false;
}
report_fatal_error("Invalid encoding");
}
/// isChar6 - Return true if this character is legal in the Char6 encoding.
static bool isChar6(char C) { return isAlnum(C) || C == '.' || C == '_'; }
static unsigned EncodeChar6(char C) {
if (C >= 'a' && C <= 'z') return C-'a';
if (C >= 'A' && C <= 'Z') return C-'A'+26;
if (C >= '0' && C <= '9') return C-'0'+26+26;
if (C == '.') return 62;
if (C == '_') return 63;
llvm_unreachable("Not a value Char6 character!");
}
static char DecodeChar6(unsigned V) {
assert((V & ~63) == 0 && "Not a Char6 encoded character!");
return "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789._"
[V];
}
};
/// BitCodeAbbrev - This class represents an abbreviation record. An
/// abbreviation allows a complex record that has redundancy to be stored in a
/// specialized format instead of the fully-general, fully-vbr, format.
class BitCodeAbbrev {
SmallVector<BitCodeAbbrevOp, 32> OperandList;
public:
BitCodeAbbrev() = default;
explicit BitCodeAbbrev(std::initializer_list<BitCodeAbbrevOp> OperandList)
: OperandList(OperandList) {}
unsigned getNumOperandInfos() const {
return static_cast<unsigned>(OperandList.size());
}
const BitCodeAbbrevOp &getOperandInfo(unsigned N) const {
return OperandList[N];
}
void Add(const BitCodeAbbrevOp &OpInfo) {
OperandList.push_back(OpInfo);
}
};
} // namespace llvm
#endif
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