Library-ize the dyld components of llvm-rtdyld.
Move the dynamic linking functionality of the llvm-rtdyld program into an
ExecutionEngine support library. Update llvm-rtdyld to just load an object
file into memory, use the library to process it, then run the _main()
function, if one is found.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128031 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/tools/llvm-rtdyld/llvm-rtdyld.cpp b/tools/llvm-rtdyld/llvm-rtdyld.cpp
index 6de5742..4e22426 100644
--- a/tools/llvm-rtdyld/llvm-rtdyld.cpp
+++ b/tools/llvm-rtdyld/llvm-rtdyld.cpp
@@ -13,6 +13,7 @@
#include "llvm/ADT/StringMap.h"
#include "llvm/ADT/OwningPtr.h"
+#include "llvm/ExecutionEngine/RuntimeDyld.h"
#include "llvm/Object/MachOObject.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/ManagedStatic.h"
@@ -51,157 +52,6 @@
}
/* *** */
-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.
@@ -209,94 +59,28 @@
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 + "'");
+ // Instantiate a dynamic linker.
+ RuntimeDyld Dyld;
- // 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;
- }
+ // Load the object file into it.
+ if (Dyld.loadObject(InputBuffer.take()))
+ return true;
// Get the address of "_main".
- StringMap<void*>::iterator it = SymbolTable.find("_main");
- if (it == SymbolTable.end())
+ void *MainAddress = Dyld.getSymbolAddress("_main");
+ if (MainAddress == 0)
return Error("no definition for '_main'");
// Invalidate the instruction cache.
+ sys::MemoryBlock Data = Dyld.getMemoryBlock();
sys::Memory::InvalidateInstructionCache(Data.base(), Data.size());
// Make sure the memory is executable.
+ std::string ErrorStr;
if (!sys::Memory::setExecutable(Data, &ErrorStr))
return Error("unable to mark function executable: '" + ErrorStr + "'");
// Dispatch to _main().
- void *MainAddress = it->second;
errs() << "loaded '_main' at: " << MainAddress << "\n";
int (*Main)(int, const char**) =