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Properly mangles symbol table names

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Supports constant pools
Supports relocations to jump tables
Supports relocations within the data segment (global = address of global)
Allocates memory in a non-hacky for all non-code objects.

llvm-svn: 32430
This commit is contained in:
Nate Begeman 2006-12-11 02:20:45 +00:00
parent 3d2e738f0c
commit b1b1aaa4e5
3 changed files with 397 additions and 159 deletions
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55
include/llvm/CodeGen/MachOWriter.h
View File

@ -19,7 +19,6 @@
#include "llvm/CodeGen/MachineRelocation.h"
#include "llvm/Target/TargetData.h"
#include "llvm/Target/TargetMachine.h"
#include <list>
namespace llvm {
class GlobalVariable;
@ -71,7 +70,8 @@ namespace llvm {
N_WEAK_DEF = 0x0080 // coalesced symbol is a weak definition
};
MachOSym(const GlobalValue *gv, std::string name, uint8_t sect);
MachOSym(const GlobalValue *gv, std::string name, uint8_t sect,
TargetMachine &TM);
};
/// MachOWriter - This class implements the common target-independent code for
@ -435,25 +435,35 @@ namespace llvm {
/// SectionList - This is the list of sections that we have emitted to the
/// file. Once the file has been completely built, the segment load command
/// SectionCommands are constructed from this info.
std::list<MachOSection> SectionList;
std::vector<MachOSection*> SectionList;
/// SectionLookup - This is a mapping from section name to SectionList entry
std::map<std::string, MachOSection*> SectionLookup;
/// GVSection - This is a mapping from a GlobalValue to a MachOSection,
/// to aid in emitting relocations.
std::map<GlobalValue*, MachOSection*> GVSection;
/// GVOffset - This is a mapping from a GlobalValue to an offset from the
/// start of the section in which the GV resides, to aid in emitting
/// relocations.
std::map<GlobalValue*, intptr_t> GVOffset;
/// getSection - Return the section with the specified name, creating a new
/// section if one does not already exist.
MachOSection &getSection(const std::string &seg, const std::string &sect,
MachOSection *getSection(const std::string &seg, const std::string &sect,
unsigned Flags = 0) {
MachOSection *&SN = SectionLookup[seg+sect];
if (SN) return *SN;
MachOSection *MOS = SectionLookup[seg+sect];
if (MOS) return MOS;
SectionList.push_back(MachOSection(seg, sect));
SN = &SectionList.back();
SN->Index = SectionList.size();
SN->flags = MachOSection::S_REGULAR | Flags;
return *SN;
MOS = new MachOSection(seg, sect);
SectionList.push_back(MOS);
MOS->Index = SectionList.size();
MOS->flags = MachOSection::S_REGULAR | Flags;
SectionLookup[seg+sect] = MOS;
return MOS;
}
MachOSection &getTextSection(bool isCode = true) {
MachOSection *getTextSection(bool isCode = true) {
if (isCode)
return getSection("__TEXT", "__text",
MachOSection::S_ATTR_PURE_INSTRUCTIONS |
@ -461,13 +471,13 @@ namespace llvm {
else
return getSection("__TEXT", "__text");
}
MachOSection &getBSSSection() {
MachOSection *getBSSSection() {
return getSection("__DATA", "__bss", MachOSection::S_ZEROFILL);
}
MachOSection &getDataSection() {
MachOSection *getDataSection() {
return getSection("__DATA", "__data");
}
MachOSection &getConstSection(const Type *Ty) {
MachOSection *getConstSection(const Type *Ty) {
// FIXME: support cstring literals and pointer literal
if (Ty->isPrimitiveType()) {
unsigned Size = TM.getTargetData()->getTypeSize(Ty);
@ -486,7 +496,7 @@ namespace llvm {
}
return getSection("__TEXT", "__const");
}
MachOSection &getJumpTableSection() {
MachOSection *getJumpTableSection() {
if (TM.getRelocationModel() == Reloc::PIC_)
return getTextSection(false);
else
@ -556,6 +566,7 @@ namespace llvm {
MachODySymTab DySymTab;
struct MachOSymCmp {
// FIXME: this does not appear to be sorting 'f' after 'F'
bool operator()(const MachOSym &LHS, const MachOSym &RHS) {
return LHS.GVName < RHS.GVName;
}
@ -687,19 +698,23 @@ namespace llvm {
P[2] = (X >> (isLittleEndian ? 16 : 8)) & 255;
P[3] = (X >> (isLittleEndian ? 24 : 0)) & 255;
}
static void InitMem(const Constant *C, void *Addr, intptr_t Offset,
const TargetData *TD,
std::vector<MachineRelocation> &MRs);
private:
void AddSymbolToSection(MachOSection &MOS, GlobalVariable *GV);
void AddSymbolToSection(MachOSection *MOS, GlobalVariable *GV);
void EmitGlobal(GlobalVariable *GV);
void EmitHeaderAndLoadCommands();
void EmitSections();
void BufferSymbolAndStringTable();
void CalculateRelocations(MachOSection &MOS, unsigned RelOffset);
void CalculateRelocations(MachOSection &MOS);
virtual MachineRelocation GetJTRelocation(unsigned Offset,
MachineBasicBlock *MBB) = 0;
virtual void GetTargetRelocation(MachineRelocation &MR, MachOSection &MOS,
unsigned ToIndex) = 0;
virtual void GetTargetRelocation(MachineRelocation &MR, MachOSection &From,
MachOSection &To) = 0;
};
}

445
lib/CodeGen/MachOWriter.cpp
View File

@ -22,16 +22,21 @@
//
//===----------------------------------------------------------------------===//
#include "llvm/Constants.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Module.h"
#include "llvm/CodeGen/MachineCodeEmitter.h"
#include "llvm/CodeGen/MachineConstantPool.h"
#include "llvm/CodeGen/MachineJumpTableInfo.h"
#include "llvm/CodeGen/MachOWriter.h"
#include "llvm/ExecutionEngine/ExecutionEngine.h"
#include "llvm/Target/TargetAsmInfo.h"
#include "llvm/Target/TargetJITInfo.h"
#include "llvm/Support/Mangler.h"
#include "llvm/Support/MathExtras.h"
#include "llvm/Support/Streams.h"
#include <algorithm>
using namespace llvm;
//===----------------------------------------------------------------------===//
@ -43,9 +48,6 @@ namespace llvm {
/// for functions to the Mach-O file.
class MachOCodeEmitter : public MachineCodeEmitter {
MachOWriter &MOW;
/// MOS - The current section we're writing to
MachOWriter::MachOSection *MOS;
/// Relocations - These are the relocations that the function needs, as
/// emitted.
@ -55,6 +57,10 @@ namespace llvm {
/// start of the section for that constant pool index.
std::vector<intptr_t> CPLocations;
/// CPSections - This is a map of constant pool indices to the MachOSection
/// containing the constant pool entry for that index.
std::vector<unsigned> CPSections;
/// JTLocations - This is a map of jump table indices to offsets from the
/// start of the section for that jump table index.
std::vector<intptr_t> JTLocations;
@ -67,10 +73,10 @@ namespace llvm {
public:
MachOCodeEmitter(MachOWriter &mow) : MOW(mow) {}
void startFunction(MachineFunction &F);
bool finishFunction(MachineFunction &F);
virtual void startFunction(MachineFunction &F);
virtual bool finishFunction(MachineFunction &F);
void addRelocation(const MachineRelocation &MR) {
virtual void addRelocation(const MachineRelocation &MR) {
Relocations.push_back(MR);
}
@ -78,8 +84,8 @@ namespace llvm {
void emitJumpTables(MachineJumpTableInfo *MJTI);
virtual intptr_t getConstantPoolEntryAddress(unsigned Index) const {
assert(0 && "CP not implementated yet!");
return 0;
assert(CPLocations.size() > Index && "CP not emitted!");
return CPLocations[Index];
}
virtual intptr_t getJumpTableEntryAddress(unsigned Index) const {
assert(JTLocations.size() > Index && "JT not emitted!");
@ -99,11 +105,11 @@ namespace llvm {
}
/// JIT SPECIFIC FUNCTIONS - DO NOT IMPLEMENT THESE HERE!
void startFunctionStub(unsigned StubSize, unsigned Alignment = 1) {
virtual void startFunctionStub(unsigned StubSize, unsigned Alignment = 1) {
assert(0 && "JIT specific function called!");
abort();
}
void *finishFunctionStub(const Function *F) {
virtual void *finishFunctionStub(const Function *F) {
assert(0 && "JIT specific function called!");
abort();
return 0;
@ -115,16 +121,26 @@ namespace llvm {
/// about to be emitted.
void MachOCodeEmitter::startFunction(MachineFunction &F) {
// Align the output buffer to the appropriate alignment, power of 2.
// FIXME: GENERICIZE!!
// FIXME: MachineFunction or TargetData should probably carry an alignment
// field for functions that we can query here instead of hard coding 4 in both
// the object writer and asm printer.
unsigned Align = 4;
// Get the Mach-O Section that this function belongs in.
MOS = &MOW.getTextSection();
MachOWriter::MachOSection *MOS = MOW.getTextSection();
// FIXME: better memory management
// FIXME: better memory management
MOS->SectionData.reserve(4096);
BufferBegin = &(MOS->SectionData[0]);
BufferBegin = &MOS->SectionData[0];
BufferEnd = BufferBegin + MOS->SectionData.capacity();
// FIXME: Using MOS->size directly here instead of calculating it from the
// output buffer size (impossible because the code emitter deals only in raw
// bytes) forces us to manually synchronize size and write padding zero bytes
// to the output buffer for all non-text sections. For text sections, we do
// not synchonize the output buffer, and we just blow up if anyone tries to
// write non-code to it. An assert should probably be added to
// AddSymbolToSection to prevent calling it on the text section.
CurBufferPtr = BufferBegin + MOS->size;
// Upgrade the section alignment if required.
@ -132,6 +148,7 @@ void MachOCodeEmitter::startFunction(MachineFunction &F) {
// Clear per-function data structures.
CPLocations.clear();
CPSections.clear();
JTLocations.clear();
MBBLocations.clear();
}
@ -139,11 +156,14 @@ void MachOCodeEmitter::startFunction(MachineFunction &F) {
/// finishFunction - This callback is invoked after the function is completely
/// finished.
bool MachOCodeEmitter::finishFunction(MachineFunction &F) {
// Get the Mach-O Section that this function belongs in.
MachOWriter::MachOSection *MOS = MOW.getTextSection();
MOS->size += CurBufferPtr - BufferBegin;
// Get a symbol for the function to add to the symbol table
const GlobalValue *FuncV = F.getFunction();
MachOSym FnSym(FuncV, MOW.Mang->getValueName(FuncV), MOS->Index);
MachOSym FnSym(FuncV, MOW.Mang->getValueName(FuncV), MOS->Index, MOW.TM);
// Emit constant pool to appropriate section(s)
emitConstantPool(F.getConstantPool());
@ -158,16 +178,21 @@ bool MachOCodeEmitter::finishFunction(MachineFunction &F) {
for (unsigned i = 0, e = Relocations.size(); i != e; ++i) {
MachineRelocation &MR = Relocations[i];
intptr_t Addr;
if (MR.isBasicBlock()) {
Addr = getMachineBasicBlockAddress(MR.getBasicBlock());
MR.setResultPointer((void *)Addr);
MR.setConstantVal(MOS->Index);
MR.setResultPointer((void*)Addr);
} else if (MR.isJumpTableIndex()) {
Addr = getJumpTableEntryAddress(MR.getJumpTableIndex());
MR.setConstantVal(MOW.getJumpTableSection()->Index);
MR.setResultPointer((void*)Addr);
} else if (MR.isConstantPoolIndex()) {
Addr = getConstantPoolEntryAddress(MR.getConstantPoolIndex());
MR.setResultPointer((void *)Addr);
} else if (MR.isJumpTableIndex()) {
// FIXME: handle PIC codegen
Addr = getJumpTableEntryAddress(MR.getJumpTableIndex());
MR.setResultPointer((void *)Addr);
MR.setConstantVal(CPSections[MR.getConstantPoolIndex()]);
MR.setResultPointer((void*)Addr);
} else if (!MR.isGlobalValue()) {
assert(0 && "Unhandled relocation type");
}
MOS->Relocations.push_back(MR);
}
@ -182,6 +207,40 @@ bool MachOCodeEmitter::finishFunction(MachineFunction &F) {
/// the constant should live in, allocate space for it, and emit it to the
/// Section data buffer.
void MachOCodeEmitter::emitConstantPool(MachineConstantPool *MCP) {
const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants();
if (CP.empty()) return;
// FIXME: handle PIC codegen
bool isPIC = MOW.TM.getRelocationModel() == Reloc::PIC_;
assert(!isPIC && "PIC codegen not yet handled for mach-o jump tables!");
// Although there is no strict necessity that I am aware of, we will do what
// gcc for OS X does and put each constant pool entry in a section of constant
// objects of a certain size. That means that float constants go in the
// literal4 section, and double objects go in literal8, etc.
//
// FIXME: revisit this decision if we ever do the "stick everything into one
// "giant object for PIC" optimization.
for (unsigned i = 0, e = CP.size(); i != e; ++i) {
const Type *Ty = CP[i].getType();
unsigned Size = MOW.TM.getTargetData()->getTypeSize(Ty);
MachOWriter::MachOSection *Sec = MOW.getConstSection(Ty);
CPLocations.push_back(Sec->SectionData.size());
CPSections.push_back(Sec->Index);
// FIXME: remove when we have unified size + output buffer
Sec->size += Size;
// Allocate space in the section for the global.
// FIXME: need alignment?
// FIXME: share between here and AddSymbolToSection?
for (unsigned j = 0; j < Size; ++j)
MOW.outbyte(Sec->SectionData, 0);
MOW.InitMem(CP[i].Val.ConstVal, &Sec->SectionData[0], CPLocations[i],
MOW.TM.getTargetData(), Sec->Relocations);
}
}
/// emitJumpTables - Emit all the jump tables for a given jump table info
@ -190,28 +249,29 @@ void MachOCodeEmitter::emitJumpTables(MachineJumpTableInfo *MJTI) {
const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
if (JT.empty()) return;
// FIXME: handle PIC codegen
bool isPIC = MOW.TM.getRelocationModel() == Reloc::PIC_;
assert(!isPIC && "PIC codegen not yet handled for mach-o jump tables!");
MachOWriter::MachOSection &Sec = MOW.getJumpTableSection();
MachOWriter::MachOSection *Sec = MOW.getJumpTableSection();
unsigned TextSecIndex = MOW.getTextSection()->Index;
for (unsigned i = 0, e = JT.size(); i != e; ++i) {
// For each jump table, record its offset from the start of the section,
// reserve space for the relocations to the MBBs, and add the relocations.
const std::vector<MachineBasicBlock*> &MBBs = JT[i].MBBs;
JTLocations.push_back(Sec.SectionData.size());
JTLocations.push_back(Sec->SectionData.size());
for (unsigned mi = 0, me = MBBs.size(); mi != me; ++mi) {
MachineRelocation MR(MOW.GetJTRelocation(Sec.SectionData.size(),
MachineRelocation MR(MOW.GetJTRelocation(Sec->SectionData.size(),
MBBs[mi]));
MR.setResultPointer((void *)JTLocations[i]);
Sec.Relocations.push_back(MR);
MOW.outaddr(Sec.SectionData, 0);
MR.setConstantVal(TextSecIndex);
Sec->Relocations.push_back(MR);
MOW.outaddr(Sec->SectionData, 0);
}
}
// FIXME: it really seems like keeping these in sync is redundant, someone
// should do something about that (never access section size directly, only
// look at buffer size).
Sec.size = Sec.SectionData.size();
// FIXME: remove when we have unified size + output buffer
Sec->size = Sec->SectionData.size();
}
//===----------------------------------------------------------------------===//
@ -230,33 +290,46 @@ MachOWriter::~MachOWriter() {
delete MCE;
}
void MachOWriter::AddSymbolToSection(MachOSection &Sec, GlobalVariable *GV) {
void MachOWriter::AddSymbolToSection(MachOSection *Sec, GlobalVariable *GV) {
const Type *Ty = GV->getType()->getElementType();
unsigned Size = TM.getTargetData()->getTypeSize(Ty);
unsigned Align = Log2_32(TM.getTargetData()->getTypeAlignment(Ty));
unsigned Align = GV->getAlignment();
if (Align == 0)
Align = TM.getTargetData()->getTypeAlignment(Ty);
MachOSym Sym(GV, Mang->getValueName(GV), Sec->Index, TM);
MachOSym Sym(GV, Mang->getValueName(GV), Sec.Index);
// Reserve space in the .bss section for this symbol while maintaining the
// desired section alignment, which must be at least as much as required by
// this symbol.
if (Align) {
Sec.align = std::max(unsigned(Sec.align), Align);
Sec.size = (Sec.size + Align - 1) & ~(Align-1);
uint64_t OrigSize = Sec->size;
Align = Log2_32(Align);
Sec->align = std::max(unsigned(Sec->align), Align);
Sec->size = (Sec->size + Align - 1) & ~(Align-1);
// Add alignment padding to buffer as well.
// FIXME: remove when we have unified size + output buffer
unsigned AlignedSize = Sec->size - OrigSize;
for (unsigned i = 0; i < AlignedSize; ++i)
outbyte(Sec->SectionData, 0);
}
// Record the offset of the symbol, and then allocate space for it.
Sym.n_value = Sec.size;
Sec.size += Size;
switch (GV->getLinkage()) {
default: // weak/linkonce handled above
assert(0 && "Unexpected linkage type!");
case GlobalValue::ExternalLinkage:
Sym.n_type |= MachOSym::N_EXT;
break;
case GlobalValue::InternalLinkage:
break;
}
// FIXME: remove when we have unified size + output buffer
Sym.n_value = Sec->size;
Sec->size += Size;
SymbolTable.push_back(Sym);
// Now that we know what section the GlovalVariable is going to be emitted
// into, update our mappings.
// FIXME: We may also need to update this when outputting non-GlobalVariable
// GlobalValues such as functions.
GVSection[GV] = Sec;
GVOffset[GV] = Sec->SectionData.size();
// Allocate space in the section for the global.
for (unsigned i = 0; i < Size; ++i)
outbyte(Sec->SectionData, 0);
}
void MachOWriter::EmitGlobal(GlobalVariable *GV) {
@ -271,7 +344,7 @@ void MachOWriter::EmitGlobal(GlobalVariable *GV) {
// part of the common block if they are zero initialized and allowed to be
// merged with other symbols.
if (NoInit || GV->hasLinkOnceLinkage() || GV->hasWeakLinkage()) {
MachOSym ExtOrCommonSym(GV, Mang->getValueName(GV), MachOSym::NO_SECT);
MachOSym ExtOrCommonSym(GV, Mang->getValueName(GV), MachOSym::NO_SECT,TM);
// For undefined (N_UNDF) external (N_EXT) types, n_value is the size in
// bytes of the symbol.
ExtOrCommonSym.n_value = Size;
@ -284,7 +357,7 @@ void MachOWriter::EmitGlobal(GlobalVariable *GV) {
return;
}
// Otherwise, this symbol is part of the .bss section.
MachOSection &BSS = getBSSSection();
MachOSection *BSS = getBSSSection();
AddSymbolToSection(BSS, GV);
return;
}
@ -292,23 +365,10 @@ void MachOWriter::EmitGlobal(GlobalVariable *GV) {
// Scalar read-only data goes in a literal section if the scalar is 4, 8, or
// 16 bytes, or a cstring. Other read only data goes into a regular const
// section. Read-write data goes in the data section.
MachOSection &Sec = GV->isConstant() ? getConstSection(Ty) : getDataSection();
MachOSection *Sec = GV->isConstant() ? getConstSection(Ty) : getDataSection();
AddSymbolToSection(Sec, GV);
// FIXME: A couple significant changes are required for this to work, even for
// trivial cases such as a constant integer:
// 0. InitializeMemory needs to be split out of ExecutionEngine. We don't
// want to have to create an ExecutionEngine such as JIT just to write
// some bytes into a buffer. The only thing necessary for
// InitializeMemory to function properly should be TargetData.
//
// 1. InitializeMemory needs to be enhanced to return MachineRelocations
// rather than accessing the address of objects such basic blocks,
// constant pools, and jump tables. The client of InitializeMemory such
// as an object writer or jit emitter should then handle these relocs
// appropriately.
//
// FIXME: need to allocate memory for the global initializer.
InitMem(GV->getInitializer(), &Sec->SectionData[0], GVOffset[GV],
TM.getTargetData(), Sec->Relocations);
}
@ -341,10 +401,6 @@ bool MachOWriter::doFinalization(Module &M) {
I != E; ++I)
EmitGlobal(I);
// Emit the symbol table to temporary buffers, so that we know the size of
// the string table when we write the load commands in the next phase.
BufferSymbolAndStringTable();
// Emit the header and load commands.
EmitHeaderAndLoadCommands();
@ -371,7 +427,7 @@ void MachOWriter::EmitHeaderAndLoadCommands() {
MachOSegment SEG("", is64Bit);
SEG.nsects = SectionList.size();
SEG.cmdsize = SEG.cmdSize(is64Bit) +
SEG.nsects * SectionList.begin()->cmdSize(is64Bit);
SEG.nsects * SectionList[0]->cmdSize(is64Bit);
// Step #1: calculate the number of load commands. We always have at least
// one, for the LC_SEGMENT load command, plus two for the normal
@ -397,9 +453,10 @@ void MachOWriter::EmitHeaderAndLoadCommands() {
outword(FH, Header.reserved);
// Step #4: Finish filling in the segment load command and write it out
for (std::list<MachOSection>::iterator I = SectionList.begin(),
for (std::vector<MachOSection*>::iterator I = SectionList.begin(),
E = SectionList.end(); I != E; ++I)
SEG.filesize += I->size;
SEG.filesize += (*I)->size;
SEG.vmsize = SEG.filesize;
SEG.fileoff = Header.cmdSize(is64Bit) + Header.sizeofcmds;
@ -417,42 +474,49 @@ void MachOWriter::EmitHeaderAndLoadCommands() {
// Step #5: Finish filling in the fields of the MachOSections
uint64_t currentAddr = 0;
for (std::list<MachOSection>::iterator I = SectionList.begin(),
for (std::vector<MachOSection*>::iterator I = SectionList.begin(),
E = SectionList.end(); I != E; ++I) {
I->addr = currentAddr;
I->offset = currentAddr + SEG.fileoff;
MachOSection *MOS = *I;
MOS->addr = currentAddr;
MOS->offset = currentAddr + SEG.fileoff;
// FIXME: do we need to do something with alignment here?
currentAddr += I->size;
currentAddr += MOS->size;
}
// Step #6: Calculate the number of relocations for each section and write out
// the section commands for each section
currentAddr += SEG.fileoff;
for (std::list<MachOSection>::iterator I = SectionList.begin(),
for (std::vector<MachOSection*>::iterator I = SectionList.begin(),
E = SectionList.end(); I != E; ++I) {
// calculate the relocation info for this section command
CalculateRelocations(*I, currentAddr);
currentAddr += I->nreloc * 8;
MachOSection *MOS = *I;
// Convert the relocations to target-specific relocations, and fill in the
// relocation offset for this section.
CalculateRelocations(*MOS);
MOS->reloff = MOS->nreloc ? currentAddr : 0;
currentAddr += MOS->nreloc * 8;
// write the finalized section command to the output buffer
outstring(FH, I->sectname, 16);
outstring(FH, I->segname, 16);
outaddr(FH, I->addr);
outaddr(FH, I->size);
outword(FH, I->offset);
outword(FH, I->align);
outword(FH, I->reloff);
outword(FH, I->nreloc);
outword(FH, I->flags);
outword(FH, I->reserved1);
outword(FH, I->reserved2);
outstring(FH, MOS->sectname, 16);
outstring(FH, MOS->segname, 16);
outaddr(FH, MOS->addr);
outaddr(FH, MOS->size);
outword(FH, MOS->offset);
outword(FH, MOS->align);
outword(FH, MOS->reloff);
outword(FH, MOS->nreloc);
outword(FH, MOS->flags);
outword(FH, MOS->reserved1);
outword(FH, MOS->reserved2);
if (is64Bit)
outword(FH, I->reserved3);
outword(FH, MOS->reserved3);
}
// Step #7: Emit LC_SYMTAB/LC_DYSYMTAB load commands
// FIXME: add size of relocs
// Step #7: Emit the symbol table to temporary buffers, so that we know the
// size of the string table when we write the next load command.
BufferSymbolAndStringTable();
// Step #8: Emit LC_SYMTAB/LC_DYSYMTAB load commands
SymTab.symoff = currentAddr;
SymTab.nsyms = SymbolTable.size();
SymTab.stroff = SymTab.symoff + SymT.size();
@ -494,20 +558,19 @@ void MachOWriter::EmitHeaderAndLoadCommands() {
/// EmitSections - Now that we have constructed the file header and load
/// commands, emit the data for each section to the file.
void MachOWriter::EmitSections() {
for (std::list<MachOSection>::iterator I = SectionList.begin(),
for (std::vector<MachOSection*>::iterator I = SectionList.begin(),
E = SectionList.end(); I != E; ++I)
// Emit the contents of each section
O.write((char*)&I->SectionData[0], I->size);
for (std::list<MachOSection>::iterator I = SectionList.begin(),
O.write((char*)&(*I)->SectionData[0], (*I)->size);
for (std::vector<MachOSection*>::iterator I = SectionList.begin(),
E = SectionList.end(); I != E; ++I)
// Emit the relocation entry data for each section.
O.write((char*)&I->RelocBuffer[0], I->RelocBuffer.size());
O.write((char*)&(*I)->RelocBuffer[0], (*I)->RelocBuffer.size());
}
/// PartitionByLocal - Simple boolean predicate that returns true if Sym is
/// a local symbol rather than an external symbol.
bool MachOWriter::PartitionByLocal(const MachOSym &Sym) {
// FIXME: Not totally sure if private extern counts as external
return (Sym.n_type & (MachOSym::N_EXT | MachOSym::N_PEXT)) == 0;
}
@ -545,6 +608,22 @@ void MachOWriter::BufferSymbolAndStringTable() {
break;
}
}
// Calculate the starting index for each of the local, extern defined, and
// undefined symbols, as well as the number of each to put in the LC_DYSYMTAB
// load command.
for (std::vector<MachOSym>::iterator I = SymbolTable.begin(),
E = SymbolTable.end(); I != E; ++I) {
if (PartitionByLocal(*I)) {
++DySymTab.nlocalsym;
++DySymTab.iextdefsym;
} else if (PartitionByDefined(*I)) {
++DySymTab.nextdefsym;
++DySymTab.iundefsym;
} else {
++DySymTab.nundefsym;
}
}
// Write out a leading zero byte when emitting string table, for n_strx == 0
// which means an empty string.
@ -567,6 +646,13 @@ void MachOWriter::BufferSymbolAndStringTable() {
for (std::vector<MachOSym>::iterator I = SymbolTable.begin(),
E = SymbolTable.end(); I != E; ++I) {
// Add the section base address to the section offset in the n_value field
// to calculate the full address.
// FIXME: handle symbols where the n_value field is not the address
GlobalValue *GV = const_cast<GlobalValue*>(I->GV);
if (GV && GVSection[GV])
I->n_value += GVSection[GV]->addr;
// Emit nlist to buffer
outword(SymT, I->n_strx);
outbyte(SymT, I->n_type);
@ -581,23 +667,156 @@ void MachOWriter::BufferSymbolAndStringTable() {
/// and the offset into that section. From this information, create the
/// appropriate target-specific MachORelocation type and add buffer it to be
/// written out after we are finished writing out sections.
void MachOWriter::CalculateRelocations(MachOSection &MOS, unsigned RelOffset) {
void MachOWriter::CalculateRelocations(MachOSection &MOS) {
for (unsigned i = 0, e = MOS.Relocations.size(); i != e; ++i) {
// FIXME: calculate the correct offset and section index for relocated
// object.
// FIXME: somehow convey the fact that the relocation might be external
// to the relocating code.
GetTargetRelocation(MOS.Relocations[i], MOS, MOS.Index);
MachineRelocation &MR = MOS.Relocations[i];
unsigned TargetSection = MR.getConstantVal();
// Since we may not have seen the GlobalValue we were interested in yet at
// the time we emitted the relocation for it, fix it up now so that it
// points to the offset into the correct section.
if (MR.isGlobalValue()) {
GlobalValue *GV = MR.getGlobalValue();
MachOSection *MOSPtr = GVSection[GV];
intptr_t offset = GVOffset[GV];
assert(MOSPtr && "Trying to relocate unknown global!");
TargetSection = MOSPtr->Index;
MR.setResultPointer((void*)offset);
}
GetTargetRelocation(MR, MOS, *SectionList[TargetSection-1]);
}
if (MOS.nreloc != 0)
MOS.reloff = RelOffset;
}
MachOSym::MachOSym(const GlobalValue *gv, std::string name, uint8_t sect) :
GV(gv), GVName(name), n_strx(0), n_type(sect == NO_SECT ? N_UNDF : N_SECT),
n_sect(sect), n_desc(0), n_value(0) {
// FIXME: take a target machine, and then add the appropriate prefix for
// the linkage type based on the TargetAsmInfo
// InitMem - Write the value of a Constant to the specified memory location,
// converting it into bytes and relocations.
void MachOWriter::InitMem(const Constant *C, void *Addr, intptr_t Offset,
const TargetData *TD,
std::vector<MachineRelocation> &MRs) {
typedef std::pair<const Constant*, intptr_t> CPair;
std::vector<CPair> WorkList;
WorkList.push_back(CPair(C,(intptr_t)Addr + Offset));
while (!WorkList.empty()) {
const Constant *PC = WorkList.back().first;
intptr_t PA = WorkList.back().second;
WorkList.pop_back();
if (isa<UndefValue>(PC)) {
continue;
} else if (const ConstantPacked *CP = dyn_cast<ConstantPacked>(PC)) {
unsigned ElementSize =
CP->getType()->getElementType()->getPrimitiveSize();
for (unsigned i = 0, e = CP->getNumOperands(); i != e; ++i)
WorkList.push_back(CPair(CP->getOperand(i), PA+i*ElementSize));
} else if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(PC)) {
//
// FIXME: Handle ConstantExpression. See EE::getConstantValue()
//
switch (CE->getOpcode()) {
case Instruction::GetElementPtr:
case Instruction::Add:
default:
cerr << "ConstantExpr not handled as global var init: " << *CE << "\n";
abort();
break;
}
} else if (PC->getType()->isFirstClassType()) {
unsigned char *ptr = (unsigned char *)PA;
uint64_t val;
switch (PC->getType()->getTypeID()) {
case Type::BoolTyID:
case Type::UByteTyID:
case Type::SByteTyID:
ptr[0] = cast<ConstantInt>(PC)->getZExtValue();
break;
case Type::UShortTyID:
case Type::ShortTyID:
val = cast<ConstantInt>(PC)->getZExtValue();
if (TD->isBigEndian())
val = ByteSwap_16(val);
ptr[0] = val;
ptr[1] = val >> 8;
break;
case Type::UIntTyID:
case Type::IntTyID:
case Type::FloatTyID:
if (PC->getType()->getTypeID() == Type::FloatTyID) {
val = FloatToBits(cast<ConstantFP>(PC)->getValue());
} else {
val = cast<ConstantInt>(PC)->getZExtValue();
}
if (TD->isBigEndian())
val = ByteSwap_32(val);
ptr[0] = val;
ptr[1] = val >> 8;
ptr[2] = val >> 16;
ptr[3] = val >> 24;
break;
case Type::DoubleTyID:
case Type::ULongTyID:
case Type::LongTyID:
if (PC->getType()->getTypeID() == Type::DoubleTyID) {
val = DoubleToBits(cast<ConstantFP>(PC)->getValue());
} else {
val = cast<ConstantInt>(PC)->getZExtValue();
}
if (TD->isBigEndian())
val = ByteSwap_64(val);
ptr[0] = val;
ptr[1] = val >> 8;
ptr[2] = val >> 16;
ptr[3] = val >> 24;
ptr[4] = val >> 32;
ptr[5] = val >> 40;
ptr[6] = val >> 48;
ptr[7] = val >> 56;
break;
case Type::PointerTyID:
if (isa<ConstantPointerNull>(C))
memset(ptr, 0, TD->getPointerSize());
else if (const GlobalValue* GV = dyn_cast<GlobalValue>(C))
// FIXME: what about function stubs?
MRs.push_back(MachineRelocation::getGV(PA-(intptr_t)Addr,
MachineRelocation::VANILLA,
const_cast<GlobalValue*>(GV)));
else
assert(0 && "Unknown constant pointer type!");
break;
default:
cerr << "ERROR: Constant unimp for type: " << *PC->getType() << "\n";
abort();
}
} else if (isa<ConstantAggregateZero>(PC)) {
memset((void*)PA, 0, (size_t)TD->getTypeSize(PC->getType()));
} else if (const ConstantArray *CPA = dyn_cast<ConstantArray>(PC)) {
unsigned ElementSize =
CPA->getType()->getElementType()->getPrimitiveSize();
for (unsigned i = 0, e = CPA->getNumOperands(); i != e; ++i)
WorkList.push_back(CPair(CPA->getOperand(i), PA+i*ElementSize));
} else if (const ConstantStruct *CPS = dyn_cast<ConstantStruct>(PC)) {
const StructLayout *SL =
TD->getStructLayout(cast<StructType>(CPS->getType()));
for (unsigned i = 0, e = CPS->getNumOperands(); i != e; ++i)
WorkList.push_back(CPair(CPS->getOperand(i), PA+SL->MemberOffsets[i]));
} else {
cerr << "Bad Type: " << *PC->getType() << "\n";
assert(0 && "Unknown constant type to initialize memory with!");
}
}
}
MachOSym::MachOSym(const GlobalValue *gv, std::string name, uint8_t sect,
TargetMachine &TM) :
GV(gv), n_strx(0), n_type(sect == NO_SECT ? N_UNDF : N_SECT), n_sect(sect),
n_desc(0), n_value(0) {
const TargetAsmInfo *TAI = TM.getTargetAsmInfo();
switch (GV->getLinkage()) {
default:
assert(0 && "Unexpected linkage type!");
@ -606,9 +825,11 @@ MachOSym::MachOSym(const GlobalValue *gv, std::string name, uint8_t sect) :
case GlobalValue::LinkOnceLinkage:
assert(!isa<Function>(gv) && "Unexpected linkage type for Function!");
case GlobalValue::ExternalLinkage:
GVName = TAI->getGlobalPrefix() + name;
n_type |= N_EXT;
break;
case GlobalValue::InternalLinkage:
GVName = TAI->getPrivateGlobalPrefix() + name;
break;
}
}

56
lib/Target/PowerPC/PPCMachOWriter.cpp
View File

@ -31,8 +31,8 @@ namespace {
Header.cpusubtype = MachOHeader::CPU_SUBTYPE_POWERPC_ALL;
}
virtual void GetTargetRelocation(MachineRelocation &MR, MachOSection &MOS,
unsigned ToIndex);
virtual void GetTargetRelocation(MachineRelocation &MR, MachOSection &From,
MachOSection &To);
virtual MachineRelocation GetJTRelocation(unsigned Offset,
MachineBasicBlock *MBB);
@ -69,8 +69,8 @@ void llvm::addPPCMachOObjectWriterPass(FunctionPassManager &FPM,
/// MachOSection, and rewrite the instruction at the section offset if required
/// by that relocation type.
void PPCMachOWriter::GetTargetRelocation(MachineRelocation &MR,
MachOSection &MOS,
unsigned ToIndex) {
MachOSection &From,
MachOSection &To) {
uint64_t Addr = 0;
// Keep track of whether or not this is an externally defined relocation.
@ -78,7 +78,7 @@ void PPCMachOWriter::GetTargetRelocation(MachineRelocation &MR,
// Get the address of whatever it is we're relocating, if possible.
if (!isExtern)
Addr = (uintptr_t)MR.getResultPointer();
Addr = (uintptr_t)MR.getResultPointer() + To.addr;
switch ((PPC::RelocationType)MR.getRelocationType()) {
default: assert(0 && "Unknown PPC relocation type!");
@ -88,57 +88,59 @@ void PPCMachOWriter::GetTargetRelocation(MachineRelocation &MR,
case PPC::reloc_vanilla:
{
// FIXME: need to handle 64 bit vanilla relocs
MachORelocation VANILLA(MR.getMachineCodeOffset(), ToIndex, false, 2,
MachORelocation VANILLA(MR.getMachineCodeOffset(), To.Index, false, 2,
isExtern, PPC_RELOC_VANILLA);
outword(MOS.RelocBuffer, VANILLA.r_address);
outword(MOS.RelocBuffer, VANILLA.getPackedFields());
++From.nreloc;
outword(From.RelocBuffer, VANILLA.r_address);
outword(From.RelocBuffer, VANILLA.getPackedFields());
}
MOS.nreloc += 1;
fixword(MOS.SectionData, Addr, MR.getMachineCodeOffset());
fixword(From.SectionData, Addr, MR.getMachineCodeOffset());
break;
case PPC::reloc_pcrel_bx:
Addr -= MR.getMachineCodeOffset();
Addr >>= 2;
Addr &= 0xFFFFFF;
Addr <<= 2;
Addr |= (MOS.SectionData[MR.getMachineCodeOffset()] << 24);
fixword(MOS.SectionData, Addr, MR.getMachineCodeOffset());
Addr |= (From.SectionData[MR.getMachineCodeOffset()] << 24);
fixword(From.SectionData, Addr, MR.getMachineCodeOffset());
break;
case PPC::reloc_pcrel_bcx:
Addr -= MR.getMachineCodeOffset();
Addr &= 0xFFFC;
fixhalf(MOS.SectionData, Addr, MR.getMachineCodeOffset() + 2);
fixhalf(From.SectionData, Addr, MR.getMachineCodeOffset() + 2);
break;
case PPC::reloc_absolute_high:
{
MachORelocation HA16(MR.getMachineCodeOffset(), ToIndex, false, 2,
MachORelocation HA16(MR.getMachineCodeOffset(), To.Index, false, 2,
isExtern, PPC_RELOC_HA16);
MachORelocation PAIR(Addr & 0xFFFF, 0xFFFFFF, false, 2, isExtern,
PPC_RELOC_PAIR);
outword(MOS.RelocBuffer, HA16.r_address);
outword(MOS.RelocBuffer, HA16.getPackedFields());
outword(MOS.RelocBuffer, PAIR.r_address);
outword(MOS.RelocBuffer, PAIR.getPackedFields());
++From.nreloc;
++From.nreloc;
outword(From.RelocBuffer, HA16.r_address);
outword(From.RelocBuffer, HA16.getPackedFields());
outword(From.RelocBuffer, PAIR.r_address);
outword(From.RelocBuffer, PAIR.getPackedFields());
}
printf("ha16: %x\n", (unsigned)Addr);
MOS.nreloc += 2;
Addr += 0x8000;
fixhalf(MOS.SectionData, Addr >> 16, MR.getMachineCodeOffset() + 2);
fixhalf(From.SectionData, Addr >> 16, MR.getMachineCodeOffset() + 2);
break;
case PPC::reloc_absolute_low:
{
MachORelocation LO16(MR.getMachineCodeOffset(), ToIndex, false, 2,
MachORelocation LO16(MR.getMachineCodeOffset(), To.Index, false, 2,
isExtern, PPC_RELOC_LO16);
MachORelocation PAIR(Addr >> 16, 0xFFFFFF, false, 2, isExtern,
PPC_RELOC_PAIR);
outword(MOS.RelocBuffer, LO16.r_address);
outword(MOS.RelocBuffer, LO16.getPackedFields());
outword(MOS.RelocBuffer, PAIR.r_address);
outword(MOS.RelocBuffer, PAIR.getPackedFields());
++From.nreloc;
++From.nreloc;
outword(From.RelocBuffer, LO16.r_address);
outword(From.RelocBuffer, LO16.getPackedFields());
outword(From.RelocBuffer, PAIR.r_address);
outword(From.RelocBuffer, PAIR.getPackedFields());
}
printf("lo16: %x\n", (unsigned)Addr);
MOS.nreloc += 2;
fixhalf(MOS.SectionData, Addr, MR.getMachineCodeOffset() + 2);
fixhalf(From.SectionData, Addr, MR.getMachineCodeOffset() + 2);
break;
}
}