Add llvm-rtdyld support for loading 32-bit code.

Factor out the 64-bit specific bits into a helper function and add an
equivalent that loads the 32-bit sections. This allows using llvm-rtdyld on ARM.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127892 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Jim Grosbach 2011-03-18 18:54:32 +00:00
parent 05f98a39e5
commit 35fdeb7b37

View File

@ -51,6 +51,157 @@ static int Error(const Twine &Msg) {
}
/* *** */
static bool
loadSegment32(const MachOObject *Obj,
sys::MemoryBlock &Data,
const MachOObject::LoadCommandInfo *SegmentLCI,
const InMemoryStruct<macho::SymtabLoadCommand> &SymtabLC,
StringMap<void*> &SymbolTable) {
InMemoryStruct<macho::SegmentLoadCommand> Segment32LC;
Obj->ReadSegmentLoadCommand(*SegmentLCI, Segment32LC);
if (!Segment32LC)
return Error("unable to load segment load command");
// Map the segment into memory.
std::string ErrorStr;
Data = sys::Memory::AllocateRWX(Segment32LC->VMSize, 0, &ErrorStr);
if (!Data.base())
return Error("unable to allocate memory block: '" + ErrorStr + "'");
memcpy(Data.base(), Obj->getData(Segment32LC->FileOffset,
Segment32LC->FileSize).data(),
Segment32LC->FileSize);
memset((char*)Data.base() + Segment32LC->FileSize, 0,
Segment32LC->VMSize - Segment32LC->FileSize);
// Bind the section indices to address.
void **SectionBases = new void*[Segment32LC->NumSections];
for (unsigned i = 0; i != Segment32LC->NumSections; ++i) {
InMemoryStruct<macho::Section> Sect;
Obj->ReadSection(*SegmentLCI, i, Sect);
if (!Sect)
return Error("unable to load section: '" + Twine(i) + "'");
// FIXME: We don't support relocations yet.
if (Sect->NumRelocationTableEntries != 0)
return Error("not yet implemented: relocations!");
// FIXME: Improve check.
if (Sect->Flags != 0x80000400)
return Error("unsupported section type!");
SectionBases[i] = (char*) Data.base() + Sect->Address;
}
// Bind all the symbols to address.
for (unsigned i = 0; i != SymtabLC->NumSymbolTableEntries; ++i) {
InMemoryStruct<macho::SymbolTableEntry> STE;
Obj->ReadSymbolTableEntry(SymtabLC->SymbolTableOffset, i, STE);
if (!STE)
return Error("unable to read symbol: '" + Twine(i) + "'");
if (STE->SectionIndex == 0)
return Error("unexpected undefined symbol!");
unsigned Index = STE->SectionIndex - 1;
if (Index >= Segment32LC->NumSections)
return Error("invalid section index for symbol: '" + Twine() + "'");
// Get the symbol name.
StringRef Name = Obj->getStringAtIndex(STE->StringIndex);
// Get the section base address.
void *SectionBase = SectionBases[Index];
// Get the symbol address.
void *Address = (char*) SectionBase + STE->Value;
// FIXME: Check the symbol type and flags.
if (STE->Type != 0xF)
return Error("unexpected symbol type!");
if (STE->Flags != 0x0)
return Error("unexpected symbol type!");
SymbolTable[Name] = Address;
}
delete SectionBases;
return false;
}
static bool
loadSegment64(const MachOObject *Obj,
sys::MemoryBlock &Data,
const MachOObject::LoadCommandInfo *SegmentLCI,
const InMemoryStruct<macho::SymtabLoadCommand> &SymtabLC,
StringMap<void*> &SymbolTable) {
InMemoryStruct<macho::Segment64LoadCommand> Segment64LC;
Obj->ReadSegment64LoadCommand(*SegmentLCI, Segment64LC);
if (!Segment64LC)
return Error("unable to load segment load command");
// Map the segment into memory.
std::string ErrorStr;
Data = sys::Memory::AllocateRWX(Segment64LC->VMSize, 0, &ErrorStr);
if (!Data.base())
return Error("unable to allocate memory block: '" + ErrorStr + "'");
memcpy(Data.base(), Obj->getData(Segment64LC->FileOffset,
Segment64LC->FileSize).data(),
Segment64LC->FileSize);
memset((char*)Data.base() + Segment64LC->FileSize, 0,
Segment64LC->VMSize - Segment64LC->FileSize);
// Bind the section indices to address.
void **SectionBases = new void*[Segment64LC->NumSections];
for (unsigned i = 0; i != Segment64LC->NumSections; ++i) {
InMemoryStruct<macho::Section64> Sect;
Obj->ReadSection64(*SegmentLCI, i, Sect);
if (!Sect)
return Error("unable to load section: '" + Twine(i) + "'");
// FIXME: We don't support relocations yet.
if (Sect->NumRelocationTableEntries != 0)
return Error("not yet implemented: relocations!");
// FIXME: Improve check.
if (Sect->Flags != 0x80000400)
return Error("unsupported section type!");
SectionBases[i] = (char*) Data.base() + Sect->Address;
}
// Bind all the symbols to address.
for (unsigned i = 0; i != SymtabLC->NumSymbolTableEntries; ++i) {
InMemoryStruct<macho::Symbol64TableEntry> STE;
Obj->ReadSymbol64TableEntry(SymtabLC->SymbolTableOffset, i, STE);
if (!STE)
return Error("unable to read symbol: '" + Twine(i) + "'");
if (STE->SectionIndex == 0)
return Error("unexpected undefined symbol!");
unsigned Index = STE->SectionIndex - 1;
if (Index >= Segment64LC->NumSections)
return Error("invalid section index for symbol: '" + Twine() + "'");
// Get the symbol name.
StringRef Name = Obj->getStringAtIndex(STE->StringIndex);
// Get the section base address.
void *SectionBase = SectionBases[Index];
// Get the symbol address.
void *Address = (char*) SectionBase + STE->Value;
// FIXME: Check the symbol type and flags.
if (STE->Type != 0xF)
return Error("unexpected symbol type!");
if (STE->Flags != 0x0)
return Error("unexpected symbol type!");
SymbolTable[Name] = Address;
}
delete SectionBases;
return false;
}
static int executeInput() {
// Load the input memory buffer.
@ -122,73 +273,14 @@ static int executeInput() {
}
// Load the segment load command.
if (SegmentLCI->Command.Type != macho::LCT_Segment64)
return Error("Segment32 not yet implemented!");
InMemoryStruct<macho::Segment64LoadCommand> Segment64LC;
Obj->ReadSegment64LoadCommand(*SegmentLCI, Segment64LC);
if (!Segment64LC)
return Error("unable to load segment load command");
// Map the segment into memory.
sys::MemoryBlock Data = sys::Memory::AllocateRWX(Segment64LC->VMSize,
0, &ErrorStr);
if (!Data.base())
return Error("unable to allocate memory block: '" + ErrorStr + "'");
memcpy(Data.base(), Obj->getData(Segment64LC->FileOffset,
Segment64LC->FileSize).data(),
Segment64LC->FileSize);
memset((char*)Data.base() + Segment64LC->FileSize, 0,
Segment64LC->VMSize - Segment64LC->FileSize);
// Bind the section indices to address.
void **SectionBases = new void*[Segment64LC->NumSections];
for (unsigned i = 0; i != Segment64LC->NumSections; ++i) {
InMemoryStruct<macho::Section64> Sect;
Obj->ReadSection64(*SegmentLCI, i, Sect);
if (!Sect)
return Error("unable to load section: '" + Twine(i) + "'");
// FIXME: We don't support relocations yet.
if (Sect->NumRelocationTableEntries != 0)
return Error("not yet implemented: relocations!");
// FIXME: Improve check.
if (Sect->Flags != 0x80000400)
return Error("unsupported section type!");
SectionBases[i] = (char*) Data.base() + Sect->Address;
}
// Bind all the symbols to address.
sys::MemoryBlock Data;
StringMap<void*> SymbolTable;
for (unsigned i = 0; i != SymtabLC->NumSymbolTableEntries; ++i) {
InMemoryStruct<macho::Symbol64TableEntry> STE;
Obj->ReadSymbol64TableEntry(SymtabLC->SymbolTableOffset, i, STE);
if (!STE)
return Error("unable to read symbol: '" + Twine(i) + "'");
if (STE->SectionIndex == 0)
return Error("unexpected undefined symbol!");
unsigned Index = STE->SectionIndex - 1;
if (Index >= Segment64LC->NumSections)
return Error("invalid section index for symbol: '" + Twine() + "'");
// Get the symbol name.
StringRef Name = Obj->getStringAtIndex(STE->StringIndex);
// Get the section base address.
void *SectionBase = SectionBases[Index];
// Get the symbol address.
void *Address = (char*) SectionBase + STE->Value;
// FIXME: Check the symbol type and flags.
if (STE->Type != 0xF)
return Error("unexpected symbol type!");
if (STE->Flags != 0x0)
return Error("unexpected symbol type!");
SymbolTable[Name] = Address;
if (SegmentLCI->Command.Type == macho::LCT_Segment) {
if (loadSegment32(Obj.get(), Data, SegmentLCI, SymtabLC, SymbolTable))
return true;
} else {
if (loadSegment64(Obj.get(), Data, SegmentLCI, SymtabLC, SymbolTable))
return true;
}
// Get the address of "_main".