bool
XdfObject::Read(SourceManager& sm, Diagnostic& diags)
{
const llvm::MemoryBuffer& in = *sm.getBuffer(sm.getMainFileID());
InputBuffer inbuf(in);
inbuf.setLittleEndian();
// Read object header
if (inbuf.getReadableSize() < FILEHEAD_SIZE)
{
diags.Report(SourceLocation(), diag::err_object_header_unreadable);
return false;
}
unsigned long magic = ReadU32(inbuf);
if (magic != XDF_MAGIC)
{
diags.Report(SourceLocation(), diag::err_not_file_type) << "XDF";
return false;
}
unsigned long scnum = ReadU32(inbuf);
unsigned long symnum = ReadU32(inbuf);
unsigned long headers_len = ReadU32(inbuf);
if (inbuf.getReadableSize() < headers_len)
{
diags.Report(SourceLocation(), diag::err_xdf_headers_unreadable);
return false;
}
unsigned long section_offset = FILEHEAD_SIZE;
unsigned long symtab_offset = section_offset + SECTHEAD_SIZE*scnum;
unsigned long strtab_offset = symtab_offset + SYMBOL_SIZE*symnum;
ReadString read_string(in, strtab_offset,
FILEHEAD_SIZE+headers_len-strtab_offset,
diags);
// Storage for nrelocs, indexed by section number
std::vector<unsigned long> sects_nrelocs;
sects_nrelocs.reserve(scnum);
// Create sections
for (unsigned long i=0; i<scnum; ++i)
{
// Start with symbol=0 as it's not created yet; updated later.
std::auto_ptr<XdfSection> xsect(new XdfSection(SymbolRef(0)));
unsigned long name_sym_index;
IntNum lma, vma;
unsigned long align;
bool bss;
unsigned long filepos;
unsigned long nrelocs;
xsect->Read(in, section_offset+SECTHEAD_SIZE*i, &name_sym_index, &lma,
&vma, &align, &bss, &filepos, &nrelocs);
xsect->scnum = i;
// get section name from section symbol entry
inbuf.setPosition(symtab_offset+name_sym_index*SYMBOL_SIZE+8);
llvm::StringRef sectname = read_string(ReadU32(inbuf));
std::auto_ptr<Section> section(
new Section(sectname, xsect->bits != 0, bss, SourceLocation()));
section->setFilePos(filepos);
section->setVMA(vma);
section->setLMA(lma);
if (bss)
{
Bytecode& gap =
section->AppendGap(xsect->size, SourceLocation());
Diagnostic nodiags(0);
gap.CalcLen(0, nodiags); // force length calculation of gap
}
else
{
// Read section data
inbuf.setPosition(filepos);
if (inbuf.getReadableSize() < xsect->size)
{
diags.Report(SourceLocation(),
diag::err_section_data_unreadable) << sectname;
return false;
}
section->bytecodes_front().getFixed().Write(inbuf.Read(xsect->size),
xsect->size);
}
// Associate section data with section
section->AddAssocData(xsect);
// Add section to object
m_object.AppendSection(section);
sects_nrelocs.push_back(nrelocs);
}
// Create symbols
inbuf.setPosition(symtab_offset);
for (unsigned long i=0; i<symnum; ++i)
{
unsigned long sym_scnum = ReadU32(inbuf); // section number
unsigned long value = ReadU32(inbuf); // value
llvm::StringRef symname = read_string(ReadU32(inbuf));// name
unsigned long flags = ReadU32(inbuf); // flags
SymbolRef sym = m_object.getSymbol(symname);
if ((flags & XdfSymbol::XDF_GLOBAL) != 0)
sym->Declare(Symbol::GLOBAL);
else if ((flags & XdfSymbol::XDF_EXTERN) != 0)
sym->Declare(Symbol::EXTERN);
if ((flags & XdfSymbol::XDF_EQU) != 0)
sym->DefineEqu(Expr(value));
else if (sym_scnum < scnum)
{
Section& sect = m_object.getSection(sym_scnum);
Location loc = {§.bytecodes_front(), value};
sym->DefineLabel(loc);
}
// Save index in symrec data
sym->AddAssocData(std::auto_ptr<XdfSymbol>(new XdfSymbol(i)));
}
// Update section symbol info, and create section relocations
std::vector<unsigned long>::iterator nrelocsi = sects_nrelocs.begin();
for (Object::section_iterator sect=m_object.sections_begin(),
end=m_object.sections_end(); sect != end; ++sect, ++nrelocsi)
{
XdfSection* xsect = sect->getAssocData<XdfSection>();
assert(xsect != 0);
// Read relocations
inbuf.setPosition(xsect->relptr);
if (inbuf.getReadableSize() < (*nrelocsi) * RELOC_SIZE)
{
diags.Report(SourceLocation(), diag::err_section_relocs_unreadable)
<< sect->getName();
return false;
}
for (unsigned long i=0; i<(*nrelocsi); ++i)
{
unsigned long addr = ReadU32(inbuf);
unsigned long sym_index = ReadU32(inbuf);
unsigned long basesym_index = ReadU32(inbuf);
XdfReloc::Type type = static_cast<XdfReloc::Type>(ReadU8(inbuf));
XdfReloc::Size size = static_cast<XdfReloc::Size>(ReadU8(inbuf));
unsigned char shift = ReadU8(inbuf);
ReadU8(inbuf); // flags; ignored
SymbolRef sym = m_object.getSymbol(sym_index);
SymbolRef basesym(0);
if (type == XdfReloc::XDF_WRT)
basesym = m_object.getSymbol(basesym_index);
sect->AddReloc(std::auto_ptr<Reloc>(
new XdfReloc(addr, sym, basesym, type, size, shift)));
}
}
if (diags.hasErrorOccurred())
return false;
return true;
}
