forked from OSchip/llvm-project
112 lines
4.2 KiB
C++
112 lines
4.2 KiB
C++
//===- DXContainer.cpp - DXContainer object file implementation -----------===//
|
|
//
|
|
// 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
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#include "llvm/Object/DXContainer.h"
|
|
#include "llvm/BinaryFormat/DXContainer.h"
|
|
#include "llvm/Object/Error.h"
|
|
|
|
using namespace llvm;
|
|
using namespace llvm::object;
|
|
|
|
static Error parseFailed(const Twine &Msg) {
|
|
return make_error<GenericBinaryError>(Msg.str(), object_error::parse_failed);
|
|
}
|
|
|
|
template <typename T>
|
|
static Error readStruct(StringRef Buffer, const char *Src, T &Struct) {
|
|
// Don't read before the beginning or past the end of the file
|
|
if (Src < Buffer.begin() || Src + sizeof(T) > Buffer.end())
|
|
return parseFailed("Reading structure out of file bounds");
|
|
|
|
memcpy(&Struct, Src, sizeof(T));
|
|
// DXContainer is always little endian
|
|
if (sys::IsBigEndianHost)
|
|
Struct.swapBytes();
|
|
return Error::success();
|
|
}
|
|
|
|
template <typename T>
|
|
static Error readInteger(StringRef Buffer, const char *Src, T &Val) {
|
|
static_assert(std::is_integral<T>::value,
|
|
"Cannot call readInteger on non-integral type.");
|
|
assert(reinterpret_cast<uintptr_t>(Src) % alignof(T) == 0 &&
|
|
"Unaligned read of value from buffer!");
|
|
// Don't read before the beginning or past the end of the file
|
|
if (Src < Buffer.begin() || Src + sizeof(T) > Buffer.end())
|
|
return parseFailed("Reading structure out of file bounds");
|
|
|
|
Val = *reinterpret_cast<const T *>(Src);
|
|
// DXContainer is always little endian
|
|
if (sys::IsBigEndianHost)
|
|
sys::swapByteOrder(Val);
|
|
return Error::success();
|
|
}
|
|
|
|
DXContainer::DXContainer(MemoryBufferRef O) : Data(O) {}
|
|
|
|
Error DXContainer::parseHeader() {
|
|
return readStruct(Data.getBuffer(), Data.getBuffer().data(), Header);
|
|
}
|
|
|
|
Error DXContainer::parseDXILHeader(uint32_t Offset) {
|
|
if (DXIL)
|
|
return parseFailed("More than one DXIL part is present in the file");
|
|
const char *Current = Data.getBuffer().data() + Offset;
|
|
dxbc::ProgramHeader Header;
|
|
if (Error Err = readStruct(Data.getBuffer(), Current, Header))
|
|
return Err;
|
|
Current += offsetof(dxbc::ProgramHeader, Bitcode) + Header.Bitcode.Offset;
|
|
DXIL.emplace(std::make_pair(Header, Current));
|
|
return Error::success();
|
|
}
|
|
|
|
Error DXContainer::parsePartOffsets() {
|
|
const char *Current = Data.getBuffer().data() + sizeof(dxbc::Header);
|
|
for (uint32_t Part = 0; Part < Header.PartCount; ++Part) {
|
|
uint32_t PartOffset;
|
|
if (Error Err = readInteger(Data.getBuffer(), Current, PartOffset))
|
|
return Err;
|
|
Current += sizeof(uint32_t);
|
|
// We need to ensure that each part offset leaves enough space for a part
|
|
// header. To prevent overflow, we subtract the part header size from the
|
|
// buffer size, rather than adding to the offset. Since the file header is
|
|
// larger than the part header we can't reach this code unless the buffer
|
|
// is larger than the part header, so this can't underflow.
|
|
if (PartOffset > Data.getBufferSize() - sizeof(dxbc::PartHeader))
|
|
return parseFailed("Part offset points beyond boundary of the file");
|
|
PartOffsets.push_back(PartOffset);
|
|
|
|
// If this isn't a dxil part stop here...
|
|
if (Data.getBuffer().substr(PartOffset, 4) != "DXIL")
|
|
continue;
|
|
if (Error Err = parseDXILHeader(PartOffset + sizeof(dxbc::PartHeader)))
|
|
return Err;
|
|
}
|
|
return Error::success();
|
|
}
|
|
|
|
Expected<DXContainer> DXContainer::create(MemoryBufferRef Object) {
|
|
DXContainer Container(Object);
|
|
if (Error Err = Container.parseHeader())
|
|
return std::move(Err);
|
|
if (Error Err = Container.parsePartOffsets())
|
|
return std::move(Err);
|
|
return Container;
|
|
}
|
|
|
|
void DXContainer::PartIterator::updateIteratorImpl(const uint32_t Offset) {
|
|
StringRef Buffer = Container.Data.getBuffer();
|
|
const char *Current = Buffer.data() + Offset;
|
|
// Offsets are validated during parsing, so all offsets in the container are
|
|
// valid and contain enough readable data to read a header.
|
|
cantFail(readStruct(Buffer, Current, IteratorState.Part));
|
|
IteratorState.Data =
|
|
StringRef(Current + sizeof(dxbc::PartHeader), IteratorState.Part.Size);
|
|
IteratorState.Offset = Offset;
|
|
}
|