[llvm-commits] [llvm] r127892 - /llvm/trunk/tools/llvm-rtdyld/llvm-rtdyld.cpp
Jim Grosbach
grosbach at apple.com
Fri Mar 18 11:54:32 PDT 2011
Author: grosbach
Date: Fri Mar 18 13:54:32 2011
New Revision: 127892
URL: http://llvm.org/viewvc/llvm-project?rev=127892&view=rev
Log:
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.
Modified:
llvm/trunk/tools/llvm-rtdyld/llvm-rtdyld.cpp
Modified: llvm/trunk/tools/llvm-rtdyld/llvm-rtdyld.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/tools/llvm-rtdyld/llvm-rtdyld.cpp?rev=127892&r1=127891&r2=127892&view=diff
==============================================================================
--- llvm/trunk/tools/llvm-rtdyld/llvm-rtdyld.cpp (original)
+++ llvm/trunk/tools/llvm-rtdyld/llvm-rtdyld.cpp Fri Mar 18 13:54:32 2011
@@ -51,87 +51,96 @@
}
/* *** */
+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");
-static int executeInput() {
- // Load the input memory buffer.
- OwningPtr<MemoryBuffer> InputBuffer;
- if (error_code ec = MemoryBuffer::getFileOrSTDIN(InputFile, InputBuffer))
- return Error("unable to read input: '" + ec.message() + "'");
-
- // Load the Mach-O wrapper object.
+ // Map the segment into memory.
std::string ErrorStr;
- OwningPtr<MachOObject> Obj(
- MachOObject::LoadFromBuffer(InputBuffer.take(), &ErrorStr));
- if (!Obj)
- return Error("unable to load object: '" + 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);
- // Validate that the load commands match what we expect.
- const MachOObject::LoadCommandInfo *SegmentLCI = 0, *SymtabLCI = 0,
- *DysymtabLCI = 0;
- for (unsigned i = 0; i != Obj->getHeader().NumLoadCommands; ++i) {
- const MachOObject::LoadCommandInfo &LCI = Obj->getLoadCommandInfo(i);
- switch (LCI.Command.Type) {
- case macho::LCT_Segment:
- case macho::LCT_Segment64:
- if (SegmentLCI)
- return Error("unexpected input object (multiple segments)");
- SegmentLCI = &LCI;
- break;
- case macho::LCT_Symtab:
- if (SymtabLCI)
- return Error("unexpected input object (multiple symbol tables)");
- SymtabLCI = &LCI;
- break;
- case macho::LCT_Dysymtab:
- if (DysymtabLCI)
- return Error("unexpected input object (multiple symbol tables)");
- DysymtabLCI = &LCI;
- break;
- default:
- return Error("unexpected input object (unexpected load command");
- }
+ // 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;
}
- if (!SymtabLCI)
- return Error("no symbol table found in object");
- if (!SegmentLCI)
- return Error("no symbol table found in object");
+ // 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!");
- // Read and register the symbol table data.
- InMemoryStruct<macho::SymtabLoadCommand> SymtabLC;
- Obj->ReadSymtabLoadCommand(*SymtabLCI, SymtabLC);
- if (!SymtabLC)
- return Error("unable to load symbol table load command");
- Obj->RegisterStringTable(*SymtabLC);
+ unsigned Index = STE->SectionIndex - 1;
+ if (Index >= Segment32LC->NumSections)
+ return Error("invalid section index for symbol: '" + Twine() + "'");
- // Read the dynamic link-edit information, if present (not present in static
- // objects).
- if (DysymtabLCI) {
- InMemoryStruct<macho::DysymtabLoadCommand> DysymtabLC;
- Obj->ReadDysymtabLoadCommand(*DysymtabLCI, DysymtabLC);
- if (!DysymtabLC)
- return Error("unable to load dynamic link-exit load command");
+ // Get the symbol name.
+ StringRef Name = Obj->getStringAtIndex(STE->StringIndex);
- // FIXME: We don't support anything interesting yet.
- if (DysymtabLC->LocalSymbolsIndex != 0)
- return Error("NOT YET IMPLEMENTED: local symbol entries");
- if (DysymtabLC->ExternalSymbolsIndex != 0)
- return Error("NOT YET IMPLEMENTED: non-external symbol entries");
- if (DysymtabLC->UndefinedSymbolsIndex != SymtabLC->NumSymbolTableEntries)
- return Error("NOT YET IMPLEMENTED: undefined symbol entries");
+ // 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;
}
- // Load the segment load command.
- if (SegmentLCI->Command.Type != macho::LCT_Segment64)
- return Error("Segment32 not yet implemented!");
+ 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.
- sys::MemoryBlock Data = sys::Memory::AllocateRWX(Segment64LC->VMSize,
- 0, &ErrorStr);
+ 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,
@@ -160,7 +169,6 @@
}
// Bind all the symbols to address.
- StringMap<void*> SymbolTable;
for (unsigned i = 0; i != SymtabLC->NumSymbolTableEntries; ++i) {
InMemoryStruct<macho::Symbol64TableEntry> STE;
Obj->ReadSymbol64TableEntry(SymtabLC->SymbolTableOffset, i, STE);
@@ -191,6 +199,90 @@
SymbolTable[Name] = Address;
}
+ delete SectionBases;
+ return false;
+}
+
+static int executeInput() {
+ // Load the input memory buffer.
+ OwningPtr<MemoryBuffer> InputBuffer;
+ if (error_code ec = MemoryBuffer::getFileOrSTDIN(InputFile, InputBuffer))
+ return Error("unable to read input: '" + ec.message() + "'");
+
+ // Load the Mach-O wrapper object.
+ std::string ErrorStr;
+ OwningPtr<MachOObject> Obj(
+ MachOObject::LoadFromBuffer(InputBuffer.take(), &ErrorStr));
+ if (!Obj)
+ return Error("unable to load object: '" + ErrorStr + "'");
+
+ // Validate that the load commands match what we expect.
+ const MachOObject::LoadCommandInfo *SegmentLCI = 0, *SymtabLCI = 0,
+ *DysymtabLCI = 0;
+ for (unsigned i = 0; i != Obj->getHeader().NumLoadCommands; ++i) {
+ const MachOObject::LoadCommandInfo &LCI = Obj->getLoadCommandInfo(i);
+ switch (LCI.Command.Type) {
+ case macho::LCT_Segment:
+ case macho::LCT_Segment64:
+ if (SegmentLCI)
+ return Error("unexpected input object (multiple segments)");
+ SegmentLCI = &LCI;
+ break;
+ case macho::LCT_Symtab:
+ if (SymtabLCI)
+ return Error("unexpected input object (multiple symbol tables)");
+ SymtabLCI = &LCI;
+ break;
+ case macho::LCT_Dysymtab:
+ if (DysymtabLCI)
+ return Error("unexpected input object (multiple symbol tables)");
+ DysymtabLCI = &LCI;
+ break;
+ default:
+ return Error("unexpected input object (unexpected load command");
+ }
+ }
+
+ if (!SymtabLCI)
+ return Error("no symbol table found in object");
+ if (!SegmentLCI)
+ return Error("no symbol table found in object");
+
+ // Read and register the symbol table data.
+ InMemoryStruct<macho::SymtabLoadCommand> SymtabLC;
+ Obj->ReadSymtabLoadCommand(*SymtabLCI, SymtabLC);
+ if (!SymtabLC)
+ return Error("unable to load symbol table load command");
+ Obj->RegisterStringTable(*SymtabLC);
+
+ // Read the dynamic link-edit information, if present (not present in static
+ // objects).
+ if (DysymtabLCI) {
+ InMemoryStruct<macho::DysymtabLoadCommand> DysymtabLC;
+ Obj->ReadDysymtabLoadCommand(*DysymtabLCI, DysymtabLC);
+ if (!DysymtabLC)
+ return Error("unable to load dynamic link-exit load command");
+
+ // FIXME: We don't support anything interesting yet.
+ if (DysymtabLC->LocalSymbolsIndex != 0)
+ return Error("NOT YET IMPLEMENTED: local symbol entries");
+ if (DysymtabLC->ExternalSymbolsIndex != 0)
+ return Error("NOT YET IMPLEMENTED: non-external symbol entries");
+ if (DysymtabLC->UndefinedSymbolsIndex != SymtabLC->NumSymbolTableEntries)
+ return Error("NOT YET IMPLEMENTED: undefined symbol entries");
+ }
+
+ // Load the segment load command.
+ sys::MemoryBlock Data;
+ StringMap<void*> SymbolTable;
+ 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".
StringMap<void*>::iterator it = SymbolTable.find("_main");
if (it == SymbolTable.end())
More information about the llvm-commits
mailing list