283 lines
11 KiB
C++
283 lines
11 KiB
C++
//===- llvm/Bitcode/BitcodeReader.h - Bitcode reader ------------*- 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 interfaces to read LLVM bitcode files/streams.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#ifndef LLVM_BITCODE_BITCODEREADER_H
|
|
#define LLVM_BITCODE_BITCODEREADER_H
|
|
|
|
#include "llvm/ADT/ArrayRef.h"
|
|
#include "llvm/ADT/StringRef.h"
|
|
#include "llvm/Bitstream/BitCodes.h"
|
|
#include "llvm/IR/ModuleSummaryIndex.h"
|
|
#include "llvm/Support/Endian.h"
|
|
#include "llvm/Support/Error.h"
|
|
#include "llvm/Support/ErrorOr.h"
|
|
#include "llvm/Support/MemoryBuffer.h"
|
|
#include <cstdint>
|
|
#include <memory>
|
|
#include <string>
|
|
#include <system_error>
|
|
#include <vector>
|
|
namespace llvm {
|
|
|
|
class LLVMContext;
|
|
class Module;
|
|
|
|
typedef llvm::function_ref<Optional<std::string>(StringRef)>
|
|
DataLayoutCallbackTy;
|
|
|
|
// These functions are for converting Expected/Error values to
|
|
// ErrorOr/std::error_code for compatibility with legacy clients. FIXME:
|
|
// Remove these functions once no longer needed by the C and libLTO APIs.
|
|
|
|
std::error_code errorToErrorCodeAndEmitErrors(LLVMContext &Ctx, Error Err);
|
|
|
|
template <typename T>
|
|
ErrorOr<T> expectedToErrorOrAndEmitErrors(LLVMContext &Ctx, Expected<T> Val) {
|
|
if (!Val)
|
|
return errorToErrorCodeAndEmitErrors(Ctx, Val.takeError());
|
|
return std::move(*Val);
|
|
}
|
|
|
|
struct BitcodeFileContents;
|
|
|
|
/// Basic information extracted from a bitcode module to be used for LTO.
|
|
struct BitcodeLTOInfo {
|
|
bool IsThinLTO;
|
|
bool HasSummary;
|
|
bool EnableSplitLTOUnit;
|
|
};
|
|
|
|
/// Represents a module in a bitcode file.
|
|
class BitcodeModule {
|
|
// This covers the identification (if present) and module blocks.
|
|
ArrayRef<uint8_t> Buffer;
|
|
StringRef ModuleIdentifier;
|
|
|
|
// The string table used to interpret this module.
|
|
StringRef Strtab;
|
|
|
|
// The bitstream location of the IDENTIFICATION_BLOCK.
|
|
uint64_t IdentificationBit;
|
|
|
|
// The bitstream location of this module's MODULE_BLOCK.
|
|
uint64_t ModuleBit;
|
|
|
|
BitcodeModule(ArrayRef<uint8_t> Buffer, StringRef ModuleIdentifier,
|
|
uint64_t IdentificationBit, uint64_t ModuleBit)
|
|
: Buffer(Buffer), ModuleIdentifier(ModuleIdentifier),
|
|
IdentificationBit(IdentificationBit), ModuleBit(ModuleBit) {}
|
|
|
|
// Calls the ctor.
|
|
friend Expected<BitcodeFileContents>
|
|
getBitcodeFileContents(MemoryBufferRef Buffer);
|
|
|
|
Expected<std::unique_ptr<Module>>
|
|
getModuleImpl(LLVMContext &Context, bool MaterializeAll,
|
|
bool ShouldLazyLoadMetadata, bool IsImporting,
|
|
DataLayoutCallbackTy DataLayoutCallback);
|
|
|
|
public:
|
|
StringRef getBuffer() const {
|
|
return StringRef((const char *)Buffer.begin(), Buffer.size());
|
|
}
|
|
|
|
StringRef getStrtab() const { return Strtab; }
|
|
|
|
StringRef getModuleIdentifier() const { return ModuleIdentifier; }
|
|
|
|
/// Read the bitcode module and prepare for lazy deserialization of function
|
|
/// bodies. If ShouldLazyLoadMetadata is true, lazily load metadata as well.
|
|
/// If IsImporting is true, this module is being parsed for ThinLTO
|
|
/// importing into another module.
|
|
Expected<std::unique_ptr<Module>> getLazyModule(LLVMContext &Context,
|
|
bool ShouldLazyLoadMetadata,
|
|
bool IsImporting);
|
|
|
|
/// Read the entire bitcode module and return it.
|
|
Expected<std::unique_ptr<Module>> parseModule(
|
|
LLVMContext &Context, DataLayoutCallbackTy DataLayoutCallback =
|
|
[](StringRef) { return None; });
|
|
|
|
/// Returns information about the module to be used for LTO: whether to
|
|
/// compile with ThinLTO, and whether it has a summary.
|
|
Expected<BitcodeLTOInfo> getLTOInfo();
|
|
|
|
/// Parse the specified bitcode buffer, returning the module summary index.
|
|
Expected<std::unique_ptr<ModuleSummaryIndex>> getSummary();
|
|
|
|
/// Parse the specified bitcode buffer and merge its module summary index
|
|
/// into CombinedIndex.
|
|
Error readSummary(ModuleSummaryIndex &CombinedIndex, StringRef ModulePath,
|
|
uint64_t ModuleId);
|
|
};
|
|
|
|
struct BitcodeFileContents {
|
|
std::vector<BitcodeModule> Mods;
|
|
StringRef Symtab, StrtabForSymtab;
|
|
};
|
|
|
|
/// Returns the contents of a bitcode file. This includes the raw contents of
|
|
/// the symbol table embedded in the bitcode file. Clients which require a
|
|
/// symbol table should prefer to use irsymtab::read instead of this function
|
|
/// because it creates a reader for the irsymtab and handles upgrading bitcode
|
|
/// files without a symbol table or with an old symbol table.
|
|
Expected<BitcodeFileContents> getBitcodeFileContents(MemoryBufferRef Buffer);
|
|
|
|
/// Returns a list of modules in the specified bitcode buffer.
|
|
Expected<std::vector<BitcodeModule>>
|
|
getBitcodeModuleList(MemoryBufferRef Buffer);
|
|
|
|
/// Read the header of the specified bitcode buffer and prepare for lazy
|
|
/// deserialization of function bodies. If ShouldLazyLoadMetadata is true,
|
|
/// lazily load metadata as well. If IsImporting is true, this module is
|
|
/// being parsed for ThinLTO importing into another module.
|
|
Expected<std::unique_ptr<Module>>
|
|
getLazyBitcodeModule(MemoryBufferRef Buffer, LLVMContext &Context,
|
|
bool ShouldLazyLoadMetadata = false,
|
|
bool IsImporting = false);
|
|
|
|
/// Like getLazyBitcodeModule, except that the module takes ownership of
|
|
/// the memory buffer if successful. If successful, this moves Buffer. On
|
|
/// error, this *does not* move Buffer. If IsImporting is true, this module is
|
|
/// being parsed for ThinLTO importing into another module.
|
|
Expected<std::unique_ptr<Module>> getOwningLazyBitcodeModule(
|
|
std::unique_ptr<MemoryBuffer> &&Buffer, LLVMContext &Context,
|
|
bool ShouldLazyLoadMetadata = false, bool IsImporting = false);
|
|
|
|
/// Read the header of the specified bitcode buffer and extract just the
|
|
/// triple information. If successful, this returns a string. On error, this
|
|
/// returns "".
|
|
Expected<std::string> getBitcodeTargetTriple(MemoryBufferRef Buffer);
|
|
|
|
/// Return true if \p Buffer contains a bitcode file with ObjC code (category
|
|
/// or class) in it.
|
|
Expected<bool> isBitcodeContainingObjCCategory(MemoryBufferRef Buffer);
|
|
|
|
/// Read the header of the specified bitcode buffer and extract just the
|
|
/// producer string information. If successful, this returns a string. On
|
|
/// error, this returns "".
|
|
Expected<std::string> getBitcodeProducerString(MemoryBufferRef Buffer);
|
|
|
|
/// Read the specified bitcode file, returning the module.
|
|
Expected<std::unique_ptr<Module>> parseBitcodeFile(
|
|
MemoryBufferRef Buffer, LLVMContext &Context,
|
|
DataLayoutCallbackTy DataLayoutCallback = [](StringRef) {
|
|
return None;
|
|
});
|
|
|
|
/// Returns LTO information for the specified bitcode file.
|
|
Expected<BitcodeLTOInfo> getBitcodeLTOInfo(MemoryBufferRef Buffer);
|
|
|
|
/// Parse the specified bitcode buffer, returning the module summary index.
|
|
Expected<std::unique_ptr<ModuleSummaryIndex>>
|
|
getModuleSummaryIndex(MemoryBufferRef Buffer);
|
|
|
|
/// Parse the specified bitcode buffer and merge the index into CombinedIndex.
|
|
Error readModuleSummaryIndex(MemoryBufferRef Buffer,
|
|
ModuleSummaryIndex &CombinedIndex,
|
|
uint64_t ModuleId);
|
|
|
|
/// Parse the module summary index out of an IR file and return the module
|
|
/// summary index object if found, or an empty summary if not. If Path refers
|
|
/// to an empty file and IgnoreEmptyThinLTOIndexFile is true, then
|
|
/// this function will return nullptr.
|
|
Expected<std::unique_ptr<ModuleSummaryIndex>>
|
|
getModuleSummaryIndexForFile(StringRef Path,
|
|
bool IgnoreEmptyThinLTOIndexFile = false);
|
|
|
|
/// isBitcodeWrapper - Return true if the given bytes are the magic bytes
|
|
/// for an LLVM IR bitcode wrapper.
|
|
inline bool isBitcodeWrapper(const unsigned char *BufPtr,
|
|
const unsigned char *BufEnd) {
|
|
// See if you can find the hidden message in the magic bytes :-).
|
|
// (Hint: it's a little-endian encoding.)
|
|
return BufPtr != BufEnd &&
|
|
BufPtr[0] == 0xDE &&
|
|
BufPtr[1] == 0xC0 &&
|
|
BufPtr[2] == 0x17 &&
|
|
BufPtr[3] == 0x0B;
|
|
}
|
|
|
|
/// isRawBitcode - Return true if the given bytes are the magic bytes for
|
|
/// raw LLVM IR bitcode (without a wrapper).
|
|
inline bool isRawBitcode(const unsigned char *BufPtr,
|
|
const unsigned char *BufEnd) {
|
|
// These bytes sort of have a hidden message, but it's not in
|
|
// little-endian this time, and it's a little redundant.
|
|
return BufPtr != BufEnd &&
|
|
BufPtr[0] == 'B' &&
|
|
BufPtr[1] == 'C' &&
|
|
BufPtr[2] == 0xc0 &&
|
|
BufPtr[3] == 0xde;
|
|
}
|
|
|
|
/// isBitcode - Return true if the given bytes are the magic bytes for
|
|
/// LLVM IR bitcode, either with or without a wrapper.
|
|
inline bool isBitcode(const unsigned char *BufPtr,
|
|
const unsigned char *BufEnd) {
|
|
return isBitcodeWrapper(BufPtr, BufEnd) ||
|
|
isRawBitcode(BufPtr, BufEnd);
|
|
}
|
|
|
|
/// SkipBitcodeWrapperHeader - Some systems wrap bc files with a special
|
|
/// header for padding or other reasons. The format of this header is:
|
|
///
|
|
/// struct bc_header {
|
|
/// uint32_t Magic; // 0x0B17C0DE
|
|
/// uint32_t Version; // Version, currently always 0.
|
|
/// uint32_t BitcodeOffset; // Offset to traditional bitcode file.
|
|
/// uint32_t BitcodeSize; // Size of traditional bitcode file.
|
|
/// ... potentially other gunk ...
|
|
/// };
|
|
///
|
|
/// This function is called when we find a file with a matching magic number.
|
|
/// In this case, skip down to the subsection of the file that is actually a
|
|
/// BC file.
|
|
/// If 'VerifyBufferSize' is true, check that the buffer is large enough to
|
|
/// contain the whole bitcode file.
|
|
inline bool SkipBitcodeWrapperHeader(const unsigned char *&BufPtr,
|
|
const unsigned char *&BufEnd,
|
|
bool VerifyBufferSize) {
|
|
// Must contain the offset and size field!
|
|
if (unsigned(BufEnd - BufPtr) < BWH_SizeField + 4)
|
|
return true;
|
|
|
|
unsigned Offset = support::endian::read32le(&BufPtr[BWH_OffsetField]);
|
|
unsigned Size = support::endian::read32le(&BufPtr[BWH_SizeField]);
|
|
uint64_t BitcodeOffsetEnd = (uint64_t)Offset + (uint64_t)Size;
|
|
|
|
// Verify that Offset+Size fits in the file.
|
|
if (VerifyBufferSize && BitcodeOffsetEnd > uint64_t(BufEnd-BufPtr))
|
|
return true;
|
|
BufPtr += Offset;
|
|
BufEnd = BufPtr+Size;
|
|
return false;
|
|
}
|
|
|
|
APInt readWideAPInt(ArrayRef<uint64_t> Vals, unsigned TypeBits);
|
|
|
|
const std::error_category &BitcodeErrorCategory();
|
|
enum class BitcodeError { CorruptedBitcode = 1 };
|
|
inline std::error_code make_error_code(BitcodeError E) {
|
|
return std::error_code(static_cast<int>(E), BitcodeErrorCategory());
|
|
}
|
|
|
|
} // end namespace llvm
|
|
|
|
namespace std {
|
|
|
|
template <> struct is_error_code_enum<llvm::BitcodeError> : std::true_type {};
|
|
|
|
} // end namespace std
|
|
|
|
#endif // LLVM_BITCODE_BITCODEREADER_H
|