diff options
author | Bruno Cardoso Lopes <bruno.cardoso@gmail.com> | 2009-06-11 19:16:03 +0000 |
---|---|---|
committer | Bruno Cardoso Lopes <bruno.cardoso@gmail.com> | 2009-06-11 19:16:03 +0000 |
commit | c997d45ae5d2e25643d3ccc2c4ae44dcca6cdf5b (patch) | |
tree | bf08515a7ca0c2daa4a84208bb1074e5994e204e | |
parent | 3590abfda093eb5b5e4536727d2e4195400b7716 (diff) | |
download | external_llvm-c997d45ae5d2e25643d3ccc2c4ae44dcca6cdf5b.zip external_llvm-c997d45ae5d2e25643d3ccc2c4ae44dcca6cdf5b.tar.gz external_llvm-c997d45ae5d2e25643d3ccc2c4ae44dcca6cdf5b.tar.bz2 |
Support for ELF Visibility
Emission for globals, using the correct data sections
Function alignment can be computed for each target using TargetELFWriterInfo
Some small fixes
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73201 91177308-0d34-0410-b5e6-96231b3b80d8
-rw-r--r-- | include/llvm/Target/TargetELFWriterInfo.h | 19 | ||||
-rw-r--r-- | lib/CodeGen/ELF.h | 55 | ||||
-rw-r--r-- | lib/CodeGen/ELFCodeEmitter.cpp | 19 | ||||
-rw-r--r-- | lib/CodeGen/ELFWriter.cpp | 283 | ||||
-rw-r--r-- | lib/CodeGen/ELFWriter.h | 31 | ||||
-rw-r--r-- | lib/Target/X86/X86ELFWriterInfo.cpp | 22 | ||||
-rw-r--r-- | lib/Target/X86/X86ELFWriterInfo.h | 4 | ||||
-rw-r--r-- | lib/Target/X86/X86TargetMachine.cpp | 3 |
8 files changed, 337 insertions, 99 deletions
diff --git a/include/llvm/Target/TargetELFWriterInfo.h b/include/llvm/Target/TargetELFWriterInfo.h index e266a71..809846a 100644 --- a/include/llvm/Target/TargetELFWriterInfo.h +++ b/include/llvm/Target/TargetELFWriterInfo.h @@ -14,6 +14,10 @@ #ifndef LLVM_TARGET_TARGETELFWRITERINFO_H #define LLVM_TARGET_TARGETELFWRITERINFO_H +#include "llvm/Target/TargetData.h" +#include "llvm/Target/TargetMachine.h" +#include "llvm/Function.h" + namespace llvm { //===--------------------------------------------------------------------===// @@ -21,9 +25,11 @@ namespace llvm { //===--------------------------------------------------------------------===// class TargetELFWriterInfo { + protected: // EMachine - This field is the target specific value to emit as the // e_machine member of the ELF header. unsigned short EMachine; + TargetMachine &TM; public: // Machine architectures @@ -44,10 +50,21 @@ namespace llvm { EM_X86_64 = 62 // AMD64 }; - explicit TargetELFWriterInfo(MachineType machine) : EMachine(machine) {} + explicit TargetELFWriterInfo(TargetMachine &tm) : TM(tm) {} virtual ~TargetELFWriterInfo() {} unsigned short getEMachine() const { return EMachine; } + + /// getFunctionAlignment - Returns the alignment for function 'F', targets + /// with different alignment constraints should overload this method + virtual unsigned getFunctionAlignment(const Function *F) const { + const TargetData *TD = TM.getTargetData(); + unsigned FnAlign = F->getAlignment(); + unsigned TDAlign = TD->getPointerABIAlignment(); + unsigned Align = std::max(FnAlign, TDAlign); + assert(!(Align & (Align-1)) && "Alignment is not a power of two!"); + return Align; + } }; } // end llvm namespace diff --git a/lib/CodeGen/ELF.h b/lib/CodeGen/ELF.h index c22f6ed..79c6c8c 100644 --- a/lib/CodeGen/ELF.h +++ b/lib/CodeGen/ELF.h @@ -21,12 +21,12 @@ #ifndef CODEGEN_ELF_H #define CODEGEN_ELF_H +#include "llvm/GlobalVariable.h" #include "llvm/CodeGen/MachineRelocation.h" #include "llvm/Support/DataTypes.h" #include <cstring> namespace llvm { - class GlobalVariable; // Identification Indexes enum { @@ -100,18 +100,20 @@ namespace llvm { /// table at the end of the file. struct ELFSection { + // Name of the section + std::string Name; + // ELF specific fields - std::string Name; // Name of the section. - unsigned NameIdx; // Index in .shstrtab of name, once emitted. - unsigned Type; - unsigned Flags; - uint64_t Addr; - unsigned Offset; - unsigned Size; - unsigned Link; - unsigned Info; - unsigned Align; - unsigned EntSize; + unsigned NameIdx; // sh_name - .shstrtab idx of name, once emitted. + unsigned Type; // sh_type - Section contents & semantics + unsigned Flags; // sh_flags - Section flags. + uint64_t Addr; // sh_addr - The mem addr this section is in. + unsigned Offset; // sh_offset - Offset from the file start + unsigned Size; // sh_size - The section size. + unsigned Link; // sh_link - Section header table index link. + unsigned Info; // sh_info - Auxillary information. + unsigned Align; // sh_addralign - Alignment of section. + unsigned EntSize; // sh_entsize - Size of entries in the section e // Section Header Flags enum { @@ -207,9 +209,33 @@ namespace llvm { STT_FILE = 4 }; + enum { + STV_DEFAULT = 0, // Visibility is specified by binding type + STV_INTERNAL = 1, // Defined by processor supplements + STV_HIDDEN = 2, // Not visible to other components + STV_PROTECTED = 3 // Visible in other components but not preemptable + }; + ELFSym(const GlobalValue *gv) : GV(gv), NameIdx(0), Value(0), Size(0), Info(0), Other(0), - SectionIdx(ELFSection::SHN_UNDEF) {} + SectionIdx(ELFSection::SHN_UNDEF) { + if (!GV) + return; + + switch (GV->getVisibility()) { + default: + assert(0 && "unknown visibility type"); + case GlobalValue::DefaultVisibility: + Other = STV_DEFAULT; + break; + case GlobalValue::HiddenVisibility: + Other = STV_HIDDEN; + break; + case GlobalValue::ProtectedVisibility: + Other = STV_PROTECTED; + break; + } + } void SetBind(unsigned X) { assert(X == (X & 0xF) && "Bind value out of range!"); @@ -219,6 +245,9 @@ namespace llvm { assert(X == (X & 0xF) && "Type value out of range!"); Info = (Info & 0xF0) | X; } + + static unsigned getEntrySize(bool is64Bit) + { return is64Bit ? 24 : 16; } }; } // end namespace llvm diff --git a/lib/CodeGen/ELFCodeEmitter.cpp b/lib/CodeGen/ELFCodeEmitter.cpp index c7bd873..780ec57 100644 --- a/lib/CodeGen/ELFCodeEmitter.cpp +++ b/lib/CodeGen/ELFCodeEmitter.cpp @@ -15,7 +15,6 @@ #include "llvm/Function.h" #include "llvm/CodeGen/MachineConstantPool.h" #include "llvm/CodeGen/MachineJumpTableInfo.h" -#include "llvm/Target/TargetData.h" #include "llvm/Target/TargetMachine.h" #include "llvm/Support/Debug.h" @@ -28,27 +27,21 @@ namespace llvm { /// startFunction - This callback is invoked when a new machine function is /// about to be emitted. void ELFCodeEmitter::startFunction(MachineFunction &MF) { - const TargetData *TD = TM.getTargetData(); - const Function *F = MF.getFunction(); - - // Align the output buffer to the appropriate alignment, power of 2. - unsigned FnAlign = F->getAlignment(); - unsigned TDAlign = TD->getPrefTypeAlignment(F->getType()); - unsigned Align = std::max(FnAlign, TDAlign); - assert(!(Align & (Align-1)) && "Alignment is not a power of two!"); - // Get the ELF Section that this function belongs in. ES = &EW.getTextSection(); + DOUT << "processing function: " << MF.getFunction()->getName() << "\n"; + // FIXME: better memory management, this will be replaced by BinaryObjects ES->SectionData.reserve(4096); BufferBegin = &ES->SectionData[0]; BufferEnd = BufferBegin + ES->SectionData.capacity(); - // Upgrade the section alignment if required. + // Align the output buffer with function alignment, and + // upgrade the section alignment if required + unsigned Align = + TM.getELFWriterInfo()->getFunctionAlignment(MF.getFunction()); if (ES->Align < Align) ES->Align = Align; - - // Round the size up to the correct alignment for starting the new function. ES->Size = (ES->Size + (Align-1)) & (-Align); // Snaity check on allocated space for text section diff --git a/lib/CodeGen/ELFWriter.cpp b/lib/CodeGen/ELFWriter.cpp index 3859ea3..8dd4aab 100644 --- a/lib/CodeGen/ELFWriter.cpp +++ b/lib/CodeGen/ELFWriter.cpp @@ -26,9 +26,6 @@ // ... // #N. ".shstrtab" entry - String table for the section names. // -// NOTE: This code should eventually be extended to support 64-bit ELF (this -// won't be hard), but we haven't done so yet! -// //===----------------------------------------------------------------------===// #define DEBUG_TYPE "elfwriter" @@ -36,6 +33,7 @@ #include "ELFWriter.h" #include "ELFCodeEmitter.h" #include "ELF.h" +#include "llvm/Constants.h" #include "llvm/Module.h" #include "llvm/PassManager.h" #include "llvm/DerivedTypes.h" @@ -44,10 +42,8 @@ #include "llvm/CodeGen/MachineConstantPool.h" #include "llvm/CodeGen/MachineFunctionPass.h" #include "llvm/Target/TargetData.h" -#include "llvm/Target/TargetELFWriterInfo.h" #include "llvm/Target/TargetMachine.h" #include "llvm/Support/Mangler.h" -#include "llvm/Support/OutputBuffer.h" #include "llvm/Support/Streams.h" #include "llvm/Support/raw_ostream.h" #include "llvm/Support/Debug.h" @@ -76,6 +72,7 @@ ELFWriter::ELFWriter(raw_ostream &o, TargetMachine &tm) ElfHdr = new ELFHeader(TM.getELFWriterInfo()->getEMachine(), 0, is64Bit, isLittleEndian); + TAI = TM.getTargetAsmInfo(); // Create the machine code emitter object for this target. MCE = new ELFCodeEmitter(*this); @@ -152,6 +149,11 @@ bool ELFWriter::doInitialization(Module &M) { } void ELFWriter::EmitGlobal(GlobalVariable *GV) { + + // XXX: put local symbols *before* global ones! + const Section *S = TAI->SectionForGlobal(GV); + DOUT << "Section " << S->getName() << " for global " << GV->getName() << "\n"; + // If this is an external global, emit it now. TODO: Note that it would be // better to ignore the symbol here and only add it to the symbol table if // referenced. @@ -164,13 +166,13 @@ void ELFWriter::EmitGlobal(GlobalVariable *GV) { return; } - unsigned Align = TM.getTargetData()->getPreferredAlignment(GV); - unsigned Size = - TM.getTargetData()->getTypeAllocSize(GV->getType()->getElementType()); + const TargetData *TD = TM.getTargetData(); + unsigned Align = TD->getPreferredAlignment(GV); + Constant *CV = GV->getInitializer(); + unsigned Size = TD->getTypeAllocSize(CV->getType()); - // If this global has a zero initializer, it is part of the .bss or common - // section. - if (GV->getInitializer()->isNullValue()) { + // If this global has a zero initializer, go to .bss or common section. + if (CV->isNullValue() || isa<UndefValue>(CV)) { // If this global is part of the common block, add it now. Variables are // part of the common block if they are zero initialized and allowed to be // merged with other symbols. @@ -182,14 +184,14 @@ void ELFWriter::EmitGlobal(GlobalVariable *GV) { CommonSym.Size = Size; CommonSym.SetBind(ELFSym::STB_GLOBAL); CommonSym.SetType(ELFSym::STT_OBJECT); - // TODO SOMEDAY: add ELF visibility. CommonSym.SectionIdx = ELFSection::SHN_COMMON; SymbolTable.push_back(CommonSym); + getSection(S->getName(), ELFSection::SHT_NOBITS, + ELFSection::SHF_WRITE | ELFSection::SHF_ALLOC, 1); return; } // Otherwise, this symbol is part of the .bss section. Emit it now. - // Handle alignment. Ensure section is aligned at least as much as required // by this symbol. ELFSection &BSSSection = getBSSSection(); @@ -227,11 +229,124 @@ void ELFWriter::EmitGlobal(GlobalVariable *GV) { return; } - // FIXME: handle .rodata - //assert(!GV->isConstant() && "unimp"); + /// Emit the Global symbol to the right ELF section + ELFSym GblSym(GV); + GblSym.Size = Size; + GblSym.SetType(ELFSym::STT_OBJECT); + GblSym.SetBind(ELFSym::STB_GLOBAL); + unsigned Flags = S->getFlags(); + unsigned SectType = ELFSection::SHT_PROGBITS; + unsigned SHdrFlags = ELFSection::SHF_ALLOC; + + if (Flags & SectionFlags::Code) + SHdrFlags |= ELFSection::SHF_EXECINSTR; + if (Flags & SectionFlags::Writeable) + SHdrFlags |= ELFSection::SHF_WRITE; + if (Flags & SectionFlags::Mergeable) + SHdrFlags |= ELFSection::SHF_MERGE; + if (Flags & SectionFlags::TLS) + SHdrFlags |= ELFSection::SHF_TLS; + if (Flags & SectionFlags::Strings) + SHdrFlags |= ELFSection::SHF_STRINGS; + + // Remove tab from section name prefix + std::string SectionName(S->getName()); + size_t Pos = SectionName.find("\t"); + if (Pos != std::string::npos) + SectionName.erase(Pos, 1); + + // The section alignment should be bound to the element with + // the largest alignment + ELFSection &ElfS = getSection(SectionName, SectType, SHdrFlags); + GblSym.SectionIdx = ElfS.SectionIdx; + if (Align > ElfS.Align) + ElfS.Align = Align; + + DataBuffer &GblCstBuf = ElfS.SectionData; + OutputBuffer GblCstTab(GblCstBuf, is64Bit, isLittleEndian); + + // S.Value should contain the symbol index inside the section, + // and all symbols should start on their required alignment boundary + GblSym.Value = (GblCstBuf.size() + (Align-1)) & (-Align); + GblCstBuf.insert(GblCstBuf.end(), GblSym.Value-GblCstBuf.size(), 0); + + // Emit the constant symbol to its section + EmitGlobalConstant(CV, GblCstTab); + SymbolTable.push_back(GblSym); +} - // FIXME: handle .data - //assert(0 && "unimp"); +void ELFWriter::EmitGlobalConstantStruct(const ConstantStruct *CVS, + OutputBuffer &GblCstTab) { + + // Print the fields in successive locations. Pad to align if needed! + const TargetData *TD = TM.getTargetData(); + unsigned Size = TD->getTypeAllocSize(CVS->getType()); + const StructLayout *cvsLayout = TD->getStructLayout(CVS->getType()); + uint64_t sizeSoFar = 0; + for (unsigned i = 0, e = CVS->getNumOperands(); i != e; ++i) { + const Constant* field = CVS->getOperand(i); + + // Check if padding is needed and insert one or more 0s. + uint64_t fieldSize = TD->getTypeAllocSize(field->getType()); + uint64_t padSize = ((i == e-1 ? Size : cvsLayout->getElementOffset(i+1)) + - cvsLayout->getElementOffset(i)) - fieldSize; + sizeSoFar += fieldSize + padSize; + + // Now print the actual field value. + EmitGlobalConstant(field, GblCstTab); + + // Insert padding - this may include padding to increase the size of the + // current field up to the ABI size (if the struct is not packed) as well + // as padding to ensure that the next field starts at the right offset. + for (unsigned p=0; p < padSize; p++) + GblCstTab.outbyte(0); + } + assert(sizeSoFar == cvsLayout->getSizeInBytes() && + "Layout of constant struct may be incorrect!"); +} + +void ELFWriter::EmitGlobalConstant(const Constant *CV, OutputBuffer &GblCstTab) { + const TargetData *TD = TM.getTargetData(); + unsigned Size = TD->getTypeAllocSize(CV->getType()); + + if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV)) { + if (CVA->isString()) { + std::string GblStr = CVA->getAsString(); + GblCstTab.outstring(GblStr, GblStr.length()); + } else { // Not a string. Print the values in successive locations + for (unsigned i = 0, e = CVA->getNumOperands(); i != e; ++i) + EmitGlobalConstant(CVA->getOperand(i), GblCstTab); + } + return; + } else if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV)) { + EmitGlobalConstantStruct(CVS, GblCstTab); + return; + } else if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV)) { + uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue(); + if (CFP->getType() == Type::DoubleTy) + GblCstTab.outxword(Val); + else if (CFP->getType() == Type::FloatTy) + GblCstTab.outword(Val); + else if (CFP->getType() == Type::X86_FP80Ty) { + assert(0 && "X86_FP80Ty global emission not implemented"); + } else if (CFP->getType() == Type::PPC_FP128Ty) + assert(0 && "PPC_FP128Ty global emission not implemented"); + return; + } else if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) { + if (Size == 4) + GblCstTab.outword(CI->getZExtValue()); + else if (Size == 8) + GblCstTab.outxword(CI->getZExtValue()); + else + assert(0 && "LargeInt global emission not implemented"); + return; + } else if (const ConstantVector *CP = dyn_cast<ConstantVector>(CV)) { + const VectorType *PTy = CP->getType(); + for (unsigned I = 0, E = PTy->getNumElements(); I < E; ++I) + EmitGlobalConstant(CP->getOperand(I), GblCstTab); + return; + } + assert(0 && "unknown global constant"); } @@ -243,12 +358,27 @@ bool ELFWriter::runOnMachineFunction(MachineFunction &MF) { /// doFinalization - Now that the module has been completely processed, emit /// the ELF file to 'O'. bool ELFWriter::doFinalization(Module &M) { - // Okay, the ELF header and .text sections have been completed, build the - // .data, .bss, and "common" sections next. + /// FIXME: This should be removed when moving to BinaryObjects. Since the + /// current ELFCodeEmiter uses CurrBuff, ... it doesn't update S.SectionData + /// vector size for .text sections, so this is a quick dirty fix + ELFSection &TS = getTextSection(); + if (TS.Size) + for (unsigned e=0; e<TS.Size; ++e) + TS.SectionData.push_back(TS.SectionData[e]); + + // Get .data and .bss section, they should always be present in the binary + getDataSection(); + getBSSSection(); + + // build data, bss and "common" sections. for (Module::global_iterator I = M.global_begin(), E = M.global_end(); I != E; ++I) EmitGlobal(I); + // Emit non-executable stack note + if (TAI->getNonexecutableStackDirective()) + getSection(".note.GNU-stack", ELFSection::SHT_PROGBITS, 0, 1); + // Emit the symbol table now, if non-empty. EmitSymbolTable(); @@ -274,6 +404,51 @@ bool ELFWriter::doFinalization(Module &M) { void ELFWriter::EmitRelocations() { } +/// EmitSymbol - Write symbol 'Sym' to the symbol table 'SymTabOut' +void ELFWriter::EmitSymbol(OutputBuffer &SymTabOut, ELFSym &Sym) { + if (is64Bit) { + SymTabOut.outword(Sym.NameIdx); + SymTabOut.outbyte(Sym.Info); + SymTabOut.outbyte(Sym.Other); + SymTabOut.outhalf(Sym.SectionIdx); + SymTabOut.outaddr64(Sym.Value); + SymTabOut.outxword(Sym.Size); + } else { + SymTabOut.outword(Sym.NameIdx); + SymTabOut.outaddr32(Sym.Value); + SymTabOut.outword(Sym.Size); + SymTabOut.outbyte(Sym.Info); + SymTabOut.outbyte(Sym.Other); + SymTabOut.outhalf(Sym.SectionIdx); + } +} + +/// EmitSectionHeader - Write section 'Section' header in 'TableOut' +/// Section Header Table +void ELFWriter::EmitSectionHeader(OutputBuffer &TableOut, const ELFSection &S) { + TableOut.outword(S.NameIdx); + TableOut.outword(S.Type); + if (is64Bit) { + TableOut.outxword(S.Flags); + TableOut.outaddr(S.Addr); + TableOut.outaddr(S.Offset); + TableOut.outxword(S.Size); + TableOut.outword(S.Link); + TableOut.outword(S.Info); + TableOut.outxword(S.Align); + TableOut.outxword(S.EntSize); + } else { + TableOut.outword(S.Flags); + TableOut.outaddr(S.Addr); + TableOut.outaddr(S.Offset); + TableOut.outword(S.Size); + TableOut.outword(S.Link); + TableOut.outword(S.Info); + TableOut.outword(S.Align); + TableOut.outword(S.EntSize); + } +} + /// EmitSymbolTable - If the current symbol table is non-empty, emit the string /// table for it and then the symbol table itself. void ELFWriter::EmitSymbolTable() { @@ -282,14 +457,13 @@ void ELFWriter::EmitSymbolTable() { // FIXME: compact all local symbols to the start of the symtab. unsigned FirstNonLocalSymbol = 1; - ELFSection &StrTab = getSection(".strtab", ELFSection::SHT_STRTAB, 0); - StrTab.Align = 1; - + ELFSection &StrTab = getStringTableSection(); DataBuffer &StrTabBuf = StrTab.SectionData; OutputBuffer StrTabOut(StrTabBuf, is64Bit, isLittleEndian); // Set the zero'th symbol to a null byte, as required. StrTabOut.outbyte(0); + unsigned Index = 1; for (unsigned i = 1, e = SymbolTable.size(); i != e; ++i) { // Use the name mangler to uniquify the LLVM symbol. @@ -315,35 +489,19 @@ void ELFWriter::EmitSymbolTable() { // Now that we have emitted the string table and know the offset into the // string table of each symbol, emit the symbol table itself. - ELFSection &SymTab = getSection(".symtab", ELFSection::SHT_SYMTAB, 0); + ELFSection &SymTab = getSymbolTableSection(); SymTab.Align = is64Bit ? 8 : 4; SymTab.Link = StrTab.SectionIdx; // Section Index of .strtab. SymTab.Info = FirstNonLocalSymbol; // First non-STB_LOCAL symbol. - SymTab.EntSize = is64Bit ? 24 : 16; // Size of each symtab entry. + + // Size of each symtab entry. + SymTab.EntSize = ELFSym::getEntrySize(is64Bit); + DataBuffer &SymTabBuf = SymTab.SectionData; OutputBuffer SymTabOut(SymTabBuf, is64Bit, isLittleEndian); - if (!is64Bit) { // 32-bit and 64-bit formats are shuffled a bit. - for (unsigned i = 0, e = SymbolTable.size(); i != e; ++i) { - ELFSym &Sym = SymbolTable[i]; - SymTabOut.outword(Sym.NameIdx); - SymTabOut.outaddr32(Sym.Value); - SymTabOut.outword(Sym.Size); - SymTabOut.outbyte(Sym.Info); - SymTabOut.outbyte(Sym.Other); - SymTabOut.outhalf(Sym.SectionIdx); - } - } else { - for (unsigned i = 0, e = SymbolTable.size(); i != e; ++i) { - ELFSym &Sym = SymbolTable[i]; - SymTabOut.outword(Sym.NameIdx); - SymTabOut.outbyte(Sym.Info); - SymTabOut.outbyte(Sym.Other); - SymTabOut.outhalf(Sym.SectionIdx); - SymTabOut.outaddr64(Sym.Value); - SymTabOut.outxword(Sym.Size); - } - } + for (unsigned i = 0, e = SymbolTable.size(); i != e; ++i) + EmitSymbol(SymTabOut, SymbolTable[i]); SymTab.Size = SymTabBuf.size(); } @@ -393,7 +551,7 @@ void ELFWriter::OutputSectionsAndSectionTable() { // Pass #1: Compute the file offset for each section. size_t FileOff = FileHeader.size(); // File header first. - // Emit all of the section data in order. + // Adjust alignment of all section if needed. for (std::list<ELFSection>::iterator I = SectionList.begin(), E = SectionList.end(); I != E; ++I) { @@ -401,6 +559,11 @@ void ELFWriter::OutputSectionsAndSectionTable() { if (!I->SectionIdx) continue; + if (!I->SectionData.size()) { + I->Offset = FileOff; + continue; + } + // Update Section size if (!I->Size) I->Size = I->SectionData.size(); @@ -438,30 +601,24 @@ void ELFWriter::OutputSectionsAndSectionTable() { // Emit all of the section data and build the section table itself. while (!SectionList.empty()) { const ELFSection &S = *SectionList.begin(); + DOUT << "SectionIdx: " << S.SectionIdx << ", Name: " << S.Name + << ", Size: " << S.Size << ", Offset: " << S.Offset + << ", SectionData Size: " << S.SectionData.size() << "\n"; + // Align FileOff to whatever the alignment restrictions of the section are. - if (S.Align) + if (S.Align) { for (size_t NewFileOff = (FileOff+S.Align-1) & ~(S.Align-1); FileOff != NewFileOff; ++FileOff) O << (char)0xAB; - O.write((char*)&S.SectionData[0], S.Size); - - DOUT << "SectionIdx: " << S.SectionIdx << ", Name: " << S.Name - << ", Size: " << S.Size << ", Offset: " << S.Offset << "\n"; - - FileOff += S.Size; + } - TableOut.outword(S.NameIdx); // sh_name - Symbol table name idx - TableOut.outword(S.Type); // sh_type - Section contents & semantics - TableOut.outaddr(S.Flags); // sh_flags - Section flags. - TableOut.outaddr(S.Addr); // sh_addr - The mem addr this section is in. - TableOut.outaddr(S.Offset); // sh_offset - Offset from the file start. - TableOut.outaddr(S.Size); // sh_size - The section size. - TableOut.outword(S.Link); // sh_link - Section header table index link. - TableOut.outword(S.Info); // sh_info - Auxillary information. - TableOut.outaddr(S.Align); // sh_addralign - Alignment of section. - TableOut.outaddr(S.EntSize); // sh_entsize - Size of entries in the section + if (S.SectionData.size()) { + O.write((char*)&S.SectionData[0], S.Size); + FileOff += S.Size; + } + EmitSectionHeader(TableOut, S); SectionList.pop_front(); } diff --git a/lib/CodeGen/ELFWriter.h b/lib/CodeGen/ELFWriter.h index 14a44f0..04918f7 100644 --- a/lib/CodeGen/ELFWriter.h +++ b/lib/CodeGen/ELFWriter.h @@ -16,15 +16,19 @@ #include "llvm/ADT/SetVector.h" #include "llvm/CodeGen/MachineFunctionPass.h" +#include "llvm/Support/OutputBuffer.h" +#include "llvm/Target/TargetAsmInfo.h" +#include "llvm/Target/TargetELFWriterInfo.h" #include "ELF.h" #include <list> #include <map> namespace llvm { + class ConstantStruct; + class ELFCodeEmitter; class GlobalVariable; class Mangler; class MachineCodeEmitter; - class ELFCodeEmitter; class raw_ostream; /// ELFWriter - This class implements the common target-independent code for @@ -59,6 +63,10 @@ namespace llvm { /// code for functions to the .o file. ELFCodeEmitter *MCE; + /// TAI - Target Asm Info, provide information about section names for + /// globals and other target specific stuff. + const TargetAsmInfo *TAI; + //===------------------------------------------------------------------===// // Properties inferred automatically from the target machine. //===------------------------------------------------------------------===// @@ -97,8 +105,8 @@ namespace llvm { /// getSection - Return the section with the specified name, creating a new /// section if one does not already exist. - ELFSection &getSection(const std::string &Name, - unsigned Type, unsigned Flags = 0) { + ELFSection &getSection(const std::string &Name, unsigned Type, + unsigned Flags = 0, unsigned Align = 0) { ELFSection *&SN = SectionLookup[Name]; if (SN) return *SN; @@ -108,6 +116,7 @@ namespace llvm { SN->Type = Type; SN->Flags = Flags; SN->Link = ELFSection::SHN_UNDEF; + SN->Align = Align; return *SN; } @@ -116,10 +125,19 @@ namespace llvm { ELFSection::SHF_EXECINSTR | ELFSection::SHF_ALLOC); } + ELFSection &getSymbolTableSection() { + return getSection(".symtab", ELFSection::SHT_SYMTAB, 0); + } + + ELFSection &getStringTableSection() { + return getSection(".strtab", ELFSection::SHT_STRTAB, 0, 1); + } + ELFSection &getDataSection() { return getSection(".data", ELFSection::SHT_PROGBITS, ELFSection::SHF_WRITE | ELFSection::SHF_ALLOC); } + ELFSection &getBSSSection() { return getSection(".bss", ELFSection::SHT_NOBITS, ELFSection::SHF_WRITE | ELFSection::SHF_ALLOC); @@ -144,9 +162,14 @@ namespace llvm { unsigned ELFHdr_e_shnum_Offset; // e_shnum in ELF header. private: void EmitGlobal(GlobalVariable *GV); - void EmitSymbolTable(); + void EmitGlobalConstant(const Constant *C, OutputBuffer &GblCstTab); + void EmitGlobalConstantStruct(const ConstantStruct *CVS, + OutputBuffer &GblCstTab); void EmitRelocations(); + void EmitSectionHeader(OutputBuffer &TableOut, const ELFSection &Section); void EmitSectionTableStringTable(); + void EmitSymbol(OutputBuffer &SymTabOut, ELFSym &Sym); + void EmitSymbolTable(); void OutputSectionsAndSectionTable(); }; } diff --git a/lib/Target/X86/X86ELFWriterInfo.cpp b/lib/Target/X86/X86ELFWriterInfo.cpp index 2604741..09c3185 100644 --- a/lib/Target/X86/X86ELFWriterInfo.cpp +++ b/lib/Target/X86/X86ELFWriterInfo.cpp @@ -12,8 +12,26 @@ //===----------------------------------------------------------------------===// #include "X86ELFWriterInfo.h" +#include "llvm/Target/TargetMachine.h" +#include "llvm/DerivedTypes.h" using namespace llvm; -X86ELFWriterInfo::X86ELFWriterInfo(bool is64Bit) : - TargetELFWriterInfo(is64Bit ? EM_X86_64 : EM_386) {} +X86ELFWriterInfo::X86ELFWriterInfo(TargetMachine &TM) + : TargetELFWriterInfo(TM) { + bool is64Bit = TM.getTargetData()->getPointerSizeInBits() == 64; + EMachine = is64Bit ? EM_X86_64 : EM_386; + } + X86ELFWriterInfo::~X86ELFWriterInfo() {} + +unsigned X86ELFWriterInfo::getFunctionAlignment(const Function *F) const { + unsigned FnAlign = 4; + + if (F->hasFnAttr(Attribute::OptimizeForSize)) + FnAlign = 1; + + if (F->getAlignment()) + FnAlign = Log2_32(F->getAlignment()); + + return (1 << FnAlign); +} diff --git a/lib/Target/X86/X86ELFWriterInfo.h b/lib/Target/X86/X86ELFWriterInfo.h index acfa501..e9c5bc4 100644 --- a/lib/Target/X86/X86ELFWriterInfo.h +++ b/lib/Target/X86/X86ELFWriterInfo.h @@ -20,8 +20,10 @@ namespace llvm { class X86ELFWriterInfo : public TargetELFWriterInfo { public: - X86ELFWriterInfo(bool is64Bit); + X86ELFWriterInfo(TargetMachine &TM); virtual ~X86ELFWriterInfo(); + + virtual unsigned getFunctionAlignment(const Function *F) const; }; } // end llvm namespace diff --git a/lib/Target/X86/X86TargetMachine.cpp b/lib/Target/X86/X86TargetMachine.cpp index 88ab247..dfb055f 100644 --- a/lib/Target/X86/X86TargetMachine.cpp +++ b/lib/Target/X86/X86TargetMachine.cpp @@ -133,8 +133,7 @@ X86TargetMachine::X86TargetMachine(const Module &M, const std::string &FS, DataLayout(Subtarget.getDataLayout()), FrameInfo(TargetFrameInfo::StackGrowsDown, Subtarget.getStackAlignment(), Subtarget.is64Bit() ? -8 : -4), - InstrInfo(*this), JITInfo(*this), TLInfo(*this), - ELFWriterInfo(Subtarget.is64Bit()) { + InstrInfo(*this), JITInfo(*this), TLInfo(*this), ELFWriterInfo(*this) { DefRelocModel = getRelocationModel(); // FIXME: Correctly select PIC model for Win64 stuff if (getRelocationModel() == Reloc::Default) { |