LLVM API Documentation

Main Page | Namespace List | Class Hierarchy | Alphabetical List | Class List | Directories | File List | Namespace Members | Class Members | File Members | Related Pages

PowerPCAsmPrinter.cpp

Go to the documentation of this file.
00001 //===-- PowerPCAsmPrinter.cpp - Print machine instrs to PowerPC assembly --===//
00002 // 
00003 //                     The LLVM Compiler Infrastructure
00004 //
00005 // This file was developed by the LLVM research group and is distributed under
00006 // the University of Illinois Open Source License. See LICENSE.TXT for details.
00007 // 
00008 //===----------------------------------------------------------------------===//
00009 //
00010 // This file contains a printer that converts from our internal representation
00011 // of machine-dependent LLVM code to PowerPC assembly language. This printer is
00012 // the output mechanism used by `llc'.
00013 //
00014 // Documentation at http://developer.apple.com/documentation/DeveloperTools/
00015 // Reference/Assembler/ASMIntroduction/chapter_1_section_1.html
00016 //
00017 //===----------------------------------------------------------------------===//
00018 
00019 #define DEBUG_TYPE "asmprinter"
00020 #include "PowerPC.h"
00021 #include "PowerPCTargetMachine.h"
00022 #include "llvm/Constants.h"
00023 #include "llvm/DerivedTypes.h"
00024 #include "llvm/Module.h"
00025 #include "llvm/Assembly/Writer.h"
00026 #include "llvm/CodeGen/AsmPrinter.h"
00027 #include "llvm/CodeGen/MachineConstantPool.h"
00028 #include "llvm/CodeGen/MachineFunctionPass.h"
00029 #include "llvm/CodeGen/MachineInstr.h"
00030 #include "llvm/CodeGen/ValueTypes.h"
00031 #include "llvm/Support/Mangler.h"
00032 #include "llvm/Support/MathExtras.h"
00033 #include "llvm/Support/CommandLine.h"
00034 #include "llvm/Support/Debug.h"
00035 #include "llvm/Target/MRegisterInfo.h"
00036 #include "llvm/Target/TargetInstrInfo.h"
00037 #include "llvm/ADT/Statistic.h"
00038 #include "llvm/ADT/StringExtras.h"
00039 #include <set>
00040 using namespace llvm;
00041 
00042 namespace {
00043   Statistic<> EmittedInsts("asm-printer", "Number of machine instrs printed");
00044 
00045   struct PowerPCAsmPrinter : public AsmPrinter {
00046     std::set<std::string> FnStubs, GVStubs, LinkOnceStubs;
00047     std::set<std::string> Strings;
00048     
00049     PowerPCAsmPrinter(std::ostream &O, TargetMachine &TM)
00050       : AsmPrinter(O, TM), LabelNumber(0) {}
00051 
00052     /// Unique incrementer for label values for referencing Global values.
00053     ///
00054     unsigned LabelNumber;
00055   
00056     virtual const char *getPassName() const {
00057       return "PowerPC Assembly Printer";
00058     }
00059 
00060     PowerPCTargetMachine &getTM() {
00061       return static_cast<PowerPCTargetMachine&>(TM);
00062     }
00063 
00064     /// printInstruction - This method is automatically generated by tablegen
00065     /// from the instruction set description.  This method returns true if the
00066     /// machine instruction was sufficiently described to print it, otherwise it
00067     /// returns false.
00068     bool printInstruction(const MachineInstr *MI);
00069 
00070     void printMachineInstruction(const MachineInstr *MI);
00071     void printOp(const MachineOperand &MO, bool IsCallOp = false);
00072 
00073     void printOperand(const MachineInstr *MI, unsigned OpNo, MVT::ValueType VT){
00074       const MachineOperand &MO = MI->getOperand(OpNo);
00075       if (MO.getType() == MachineOperand::MO_MachineRegister) {
00076         assert(MRegisterInfo::isPhysicalRegister(MO.getReg())&&"Not physreg??");
00077         O << LowercaseString(TM.getRegisterInfo()->get(MO.getReg()).Name);
00078       } else if (MO.isImmediate()) {
00079         O << MO.getImmedValue();
00080       } else {
00081         printOp(MO);
00082       }
00083     }
00084 
00085     void printU5ImmOperand(const MachineInstr *MI, unsigned OpNo,
00086                             MVT::ValueType VT) {
00087       unsigned char value = MI->getOperand(OpNo).getImmedValue();
00088       assert(value <= 31 && "Invalid u5imm argument!");
00089       O << (unsigned int)value;
00090     }
00091     void printU6ImmOperand(const MachineInstr *MI, unsigned OpNo,
00092                             MVT::ValueType VT) {
00093       unsigned char value = MI->getOperand(OpNo).getImmedValue();
00094       assert(value <= 63 && "Invalid u6imm argument!");
00095       O << (unsigned int)value;
00096     }
00097     void printS16ImmOperand(const MachineInstr *MI, unsigned OpNo,
00098                             MVT::ValueType VT) {
00099       O << (short)MI->getOperand(OpNo).getImmedValue();
00100     }
00101     void printU16ImmOperand(const MachineInstr *MI, unsigned OpNo,
00102                             MVT::ValueType VT) {
00103       O << (unsigned short)MI->getOperand(OpNo).getImmedValue();
00104     }
00105     void printBranchOperand(const MachineInstr *MI, unsigned OpNo,
00106                             MVT::ValueType VT) {
00107       // Branches can take an immediate operand.  This is used by the branch
00108       // selection pass to print $+8, an eight byte displacement from the PC.
00109       if (MI->getOperand(OpNo).isImmediate()) {
00110         O << "$+" << MI->getOperand(OpNo).getImmedValue() << '\n';
00111       } else {
00112         printOp(MI->getOperand(OpNo), 
00113                 TM.getInstrInfo()->isCall(MI->getOpcode()));
00114       }
00115     }
00116     void printPICLabel(const MachineInstr *MI, unsigned OpNo,
00117                        MVT::ValueType VT) {
00118       // FIXME: should probably be converted to cout.width and cout.fill
00119       O << "\"L0000" << LabelNumber << "$pb\"\n";
00120       O << "\"L0000" << LabelNumber << "$pb\":";
00121     }
00122     void printSymbolHi(const MachineInstr *MI, unsigned OpNo,
00123                        MVT::ValueType VT) {
00124       O << "ha16(";
00125       printOp(MI->getOperand(OpNo));
00126       O << "-\"L0000" << LabelNumber << "$pb\")";
00127     }
00128     void printSymbolLo(const MachineInstr *MI, unsigned OpNo,
00129                        MVT::ValueType VT) {
00130       // FIXME: Because LFS, LFD, and LWZ can be used either with a s16imm or
00131       // a lo16 of a global or constant pool operand, we must handle both here.
00132       // this isn't a great design, but it works for now.
00133       if (MI->getOperand(OpNo).isImmediate()) {
00134         O << (short)MI->getOperand(OpNo).getImmedValue();
00135       } else {
00136         O << "lo16(";
00137         printOp(MI->getOperand(OpNo));
00138         O << "-\"L0000" << LabelNumber << "$pb\")";
00139       }
00140     }
00141   
00142     virtual void printConstantPool(MachineConstantPool *MCP) = 0;
00143     virtual bool runOnMachineFunction(MachineFunction &F) = 0;    
00144     virtual bool doFinalization(Module &M) = 0;
00145   };
00146   
00147   /// DarwinAsmPrinter - PowerPC assembly printer, customized for Darwin/Mac OS
00148   /// X
00149   ///
00150   struct DarwinAsmPrinter : public PowerPCAsmPrinter {
00151 
00152     DarwinAsmPrinter(std::ostream &O, TargetMachine &TM)
00153       : PowerPCAsmPrinter(O, TM) {
00154       CommentString = ";";
00155       GlobalPrefix = "_";
00156       ZeroDirective = "\t.space\t";  // ".space N" emits N zeros.
00157       Data64bitsDirective = 0;       // we can't emit a 64-bit unit
00158       AlignmentIsInBytes = false;    // Alignment is by power of 2.
00159     }
00160 
00161     virtual const char *getPassName() const {
00162       return "Darwin PPC Assembly Printer";
00163     }
00164 
00165     void printConstantPool(MachineConstantPool *MCP);
00166     bool runOnMachineFunction(MachineFunction &F);    
00167     bool doFinalization(Module &M);
00168   };
00169   
00170   /// AIXAsmPrinter - PowerPC assembly printer, customized for AIX
00171   ///
00172   struct AIXAsmPrinter : public PowerPCAsmPrinter {
00173     /// Map for labels corresponding to global variables
00174     ///
00175     std::map<const GlobalVariable*,std::string> GVToLabelMap;
00176 
00177     AIXAsmPrinter(std::ostream &O, TargetMachine &TM)
00178       : PowerPCAsmPrinter(O, TM) {
00179       CommentString = "#";
00180       GlobalPrefix = "_";
00181       ZeroDirective = "\t.space\t";  // ".space N" emits N zeros.
00182       Data64bitsDirective = 0;       // we can't emit a 64-bit unit
00183       AlignmentIsInBytes = false;    // Alignment is by power of 2.
00184     }
00185     
00186     virtual const char *getPassName() const {
00187       return "AIX PPC Assembly Printer";
00188     }
00189 
00190     void printConstantPool(MachineConstantPool *MCP);
00191     bool runOnMachineFunction(MachineFunction &F);    
00192     bool doInitialization(Module &M);
00193     bool doFinalization(Module &M);
00194   };
00195 } // end of anonymous namespace
00196 
00197 // SwitchSection - Switch to the specified section of the executable if we are
00198 // not already in it!
00199 //
00200 static void SwitchSection(std::ostream &OS, std::string &CurSection,
00201                           const char *NewSection) {
00202   if (CurSection != NewSection) {
00203     CurSection = NewSection;
00204     if (!CurSection.empty())
00205       OS << "\t" << NewSection << "\n";
00206   }
00207 }
00208 
00209 /// isStringCompatible - Can we treat the specified array as a string?
00210 /// Only if it is an array of ubytes or non-negative sbytes.
00211 ///
00212 static bool isStringCompatible(const ConstantArray *CVA) {
00213   const Type *ETy = cast<ArrayType>(CVA->getType())->getElementType();
00214   if (ETy == Type::UByteTy) return true;
00215   if (ETy != Type::SByteTy) return false;
00216 
00217   for (unsigned i = 0; i < CVA->getNumOperands(); ++i)
00218     if (cast<ConstantSInt>(CVA->getOperand(i))->getValue() < 0)
00219       return false;
00220 
00221   return true;
00222 }
00223 
00224 /// toOctal - Convert the low order bits of X into an octal digit.
00225 ///
00226 static inline char toOctal(int X) {
00227   return (X&7)+'0';
00228 }
00229 
00230 // Possible states while outputting ASCII strings
00231 namespace {
00232   enum StringSection {
00233     None,
00234     Alpha,
00235     Numeric
00236   };
00237 }
00238 
00239 /// SwitchStringSection - manage the changes required to output bytes as
00240 /// characters in a string vs. numeric decimal values
00241 /// 
00242 static inline void SwitchStringSection(std::ostream &O, StringSection NewSect,
00243                                        StringSection &Current) {
00244   if (Current == None) {
00245     if (NewSect == Alpha)
00246       O << "\t.byte \"";
00247     else if (NewSect == Numeric)
00248       O << "\t.byte ";
00249   } else if (Current == Alpha) {
00250     if (NewSect == None)
00251       O << "\"";
00252     else if (NewSect == Numeric) 
00253       O << "\"\n"
00254         << "\t.byte ";
00255   } else if (Current == Numeric) {
00256     if (NewSect == Alpha)
00257       O << '\n'
00258         << "\t.byte \"";
00259     else if (NewSect == Numeric)
00260       O << ", ";
00261   }
00262 
00263   Current = NewSect;
00264 }
00265 
00266 /// getAsCString - Return the specified array as a C compatible
00267 /// string, only if the predicate isStringCompatible is true.
00268 ///
00269 static void printAsCString(std::ostream &O, const ConstantArray *CVA) {
00270   assert(isStringCompatible(CVA) && "Array is not string compatible!");
00271 
00272   if (CVA->getNumOperands() == 0)
00273     return;
00274 
00275   StringSection Current = None;
00276   for (unsigned i = 0, e = CVA->getNumOperands(); i != e; ++i) {
00277     unsigned char C = cast<ConstantInt>(CVA->getOperand(i))->getRawValue();
00278     if (C == '"') {
00279       SwitchStringSection(O, Alpha, Current);
00280       O << "\"\"";
00281     } else if (isprint(C)) {
00282       SwitchStringSection(O, Alpha, Current);
00283       O << C;
00284     } else {
00285       SwitchStringSection(O, Numeric, Current);
00286       O << utostr((unsigned)C);
00287     }
00288   }
00289   SwitchStringSection(O, None, Current);
00290   O << '\n';
00291 }
00292 
00293 /// createDarwinAsmPrinterPass - Returns a pass that prints the PPC assembly 
00294 /// code for a MachineFunction to the given output stream, in a format that the 
00295 /// Darwin assembler can deal with.
00296 ///
00297 FunctionPass *llvm::createDarwinAsmPrinter(std::ostream &o, TargetMachine &tm) {
00298   return new DarwinAsmPrinter(o, tm);
00299 }
00300 
00301 /// createAIXAsmPrinterPass - Returns a pass that prints the PPC assembly code
00302 /// for a MachineFunction to the given output stream, in a format that the 
00303 /// AIX 5L assembler can deal with.
00304 ///
00305 FunctionPass *llvm::createAIXAsmPrinter(std::ostream &o, TargetMachine &tm) {
00306   return new AIXAsmPrinter(o, tm);
00307 }
00308 
00309 // Include the auto-generated portion of the assembly writer
00310 #include "PowerPCGenAsmWriter.inc"
00311 
00312 void PowerPCAsmPrinter::printOp(const MachineOperand &MO, bool IsCallOp) {
00313   const MRegisterInfo &RI = *TM.getRegisterInfo();
00314   int new_symbol;
00315   
00316   switch (MO.getType()) {
00317   case MachineOperand::MO_VirtualRegister:
00318     if (Value *V = MO.getVRegValueOrNull()) {
00319       O << "<" << V->getName() << ">";
00320       return;
00321     }
00322     // FALLTHROUGH
00323   case MachineOperand::MO_MachineRegister:
00324   case MachineOperand::MO_CCRegister:
00325     O << LowercaseString(RI.get(MO.getReg()).Name);
00326     return;
00327 
00328   case MachineOperand::MO_SignExtendedImmed:
00329   case MachineOperand::MO_UnextendedImmed:
00330     std::cerr << "printOp() does not handle immediate values\n";
00331     abort();
00332     return;
00333 
00334   case MachineOperand::MO_PCRelativeDisp:
00335     std::cerr << "Shouldn't use addPCDisp() when building PPC MachineInstrs";
00336     abort();
00337     return;
00338     
00339   case MachineOperand::MO_MachineBasicBlock: {
00340     MachineBasicBlock *MBBOp = MO.getMachineBasicBlock();
00341     O << ".LBB" << Mang->getValueName(MBBOp->getParent()->getFunction())
00342       << "_" << MBBOp->getNumber() << "\t; "
00343       << MBBOp->getBasicBlock()->getName();
00344     return;
00345   }
00346 
00347   case MachineOperand::MO_ConstantPoolIndex:
00348     O << ".CPI" << CurrentFnName << "_" << MO.getConstantPoolIndex();
00349     return;
00350 
00351   case MachineOperand::MO_ExternalSymbol:
00352     O << MO.getSymbolName();
00353     return;
00354 
00355   case MachineOperand::MO_GlobalAddress: {
00356     GlobalValue *GV = MO.getGlobal();
00357     std::string Name = Mang->getValueName(GV);
00358 
00359     // Dynamically-resolved functions need a stub for the function.  Be
00360     // wary however not to output $stub for external functions whose addresses
00361     // are taken.  Those should be emitted as $non_lazy_ptr below.
00362     Function *F = dyn_cast<Function>(GV);
00363     if (F && IsCallOp && F->isExternal()) {
00364       FnStubs.insert(Name);
00365       O << "L" << Name << "$stub";
00366       return;
00367     }
00368     
00369     // External or weakly linked global variables need non-lazily-resolved stubs
00370     if ((GV->isExternal() || GV->hasWeakLinkage() || GV->hasLinkOnceLinkage())){
00371       if (GV->hasLinkOnceLinkage())
00372         LinkOnceStubs.insert(Name);
00373       else
00374         GVStubs.insert(Name);
00375       O << "L" << Name << "$non_lazy_ptr";
00376       return;
00377     }
00378 
00379     O << Mang->getValueName(GV);
00380     return;
00381   }
00382     
00383   default:
00384     O << "<unknown operand type: " << MO.getType() << ">";
00385     return;
00386   }
00387 }
00388 
00389 /// printMachineInstruction -- Print out a single PowerPC MI in Darwin syntax to
00390 /// the current output stream.
00391 ///
00392 void PowerPCAsmPrinter::printMachineInstruction(const MachineInstr *MI) {
00393   ++EmittedInsts;
00394   if (printInstruction(MI))
00395     return; // Printer was automatically generated
00396   
00397   assert(0 && "Unhandled instruction in asm writer!");
00398   abort();
00399   return;
00400 }
00401 
00402 /// runOnMachineFunction - This uses the printMachineInstruction()
00403 /// method to print assembly for each instruction.
00404 ///
00405 bool DarwinAsmPrinter::runOnMachineFunction(MachineFunction &MF) {
00406   setupMachineFunction(MF);
00407   O << "\n\n";
00408 
00409   // Print out constants referenced by the function
00410   printConstantPool(MF.getConstantPool());
00411 
00412   // Print out labels for the function.
00413   O << "\t.text\n";
00414   emitAlignment(2);
00415   O << "\t.globl\t" << CurrentFnName << "\n";
00416   O << CurrentFnName << ":\n";
00417 
00418   // Print out code for the function.
00419   for (MachineFunction::const_iterator I = MF.begin(), E = MF.end();
00420        I != E; ++I) {
00421     // Print a label for the basic block.
00422     O << ".LBB" << CurrentFnName << "_" << I->getNumber() << ":\t"
00423       << CommentString << " " << I->getBasicBlock()->getName() << "\n";
00424     for (MachineBasicBlock::const_iterator II = I->begin(), E = I->end();
00425          II != E; ++II) {
00426       // Print the assembly for the instruction.
00427       O << "\t";
00428       printMachineInstruction(II);
00429     }
00430   }
00431   ++LabelNumber;
00432 
00433   // We didn't modify anything.
00434   return false;
00435 }
00436 
00437 /// printConstantPool - Print to the current output stream assembly
00438 /// representations of the constants in the constant pool MCP. This is
00439 /// used to print out constants which have been "spilled to memory" by
00440 /// the code generator.
00441 ///
00442 void DarwinAsmPrinter::printConstantPool(MachineConstantPool *MCP) {
00443   const std::vector<Constant*> &CP = MCP->getConstants();
00444   const TargetData &TD = TM.getTargetData();
00445  
00446   if (CP.empty()) return;
00447 
00448   for (unsigned i = 0, e = CP.size(); i != e; ++i) {
00449     O << "\t.const\n";
00450     emitAlignment(TD.getTypeAlignmentShift(CP[i]->getType()));
00451     O << ".CPI" << CurrentFnName << "_" << i << ":\t\t\t\t\t" << CommentString
00452       << *CP[i] << "\n";
00453     emitGlobalConstant(CP[i]);
00454   }
00455 }
00456 
00457 bool DarwinAsmPrinter::doFinalization(Module &M) {
00458   const TargetData &TD = TM.getTargetData();
00459   std::string CurSection;
00460 
00461   // Print out module-level global variables here.
00462   for (Module::const_giterator I = M.gbegin(), E = M.gend(); I != E; ++I)
00463     if (I->hasInitializer()) {   // External global require no code
00464       O << '\n';
00465       std::string name = Mang->getValueName(I);
00466       Constant *C = I->getInitializer();
00467       unsigned Size = TD.getTypeSize(C->getType());
00468       unsigned Align = TD.getTypeAlignmentShift(C->getType());
00469 
00470       if (C->isNullValue() && /* FIXME: Verify correct */
00471           (I->hasInternalLinkage() || I->hasWeakLinkage() || 
00472            I->hasLinkOnceLinkage())) {
00473         SwitchSection(O, CurSection, ".data");
00474         if (I->hasInternalLinkage())
00475           O << ".lcomm " << name << "," << TD.getTypeSize(C->getType())
00476             << "," << Align;
00477         else 
00478           O << ".comm " << name << "," << TD.getTypeSize(C->getType());
00479         O << "\t\t; ";
00480         WriteAsOperand(O, I, true, true, &M);
00481         O << '\n';
00482       } else {
00483         switch (I->getLinkage()) {
00484         case GlobalValue::LinkOnceLinkage:
00485           O << ".section __TEXT,__textcoal_nt,coalesced,no_toc\n"
00486             << ".weak_definition " << name << '\n'
00487             << ".private_extern " << name << '\n'
00488             << ".section __DATA,__datacoal_nt,coalesced,no_toc\n";
00489           LinkOnceStubs.insert(name);
00490           break;  
00491         case GlobalValue::WeakLinkage:   // FIXME: Verify correct for weak.
00492           // Nonnull linkonce -> weak
00493           O << "\t.weak " << name << "\n";
00494           SwitchSection(O, CurSection, "");
00495           O << "\t.section\t.llvm.linkonce.d." << name << ",\"aw\",@progbits\n";
00496           break;
00497         case GlobalValue::AppendingLinkage:
00498           // FIXME: appending linkage variables should go into a section of
00499           // their name or something.  For now, just emit them as external.
00500         case GlobalValue::ExternalLinkage:
00501           // If external or appending, declare as a global symbol
00502           O << "\t.globl " << name << "\n";
00503           // FALL THROUGH
00504         case GlobalValue::InternalLinkage:
00505           SwitchSection(O, CurSection, ".data");
00506           break;
00507         case GlobalValue::GhostLinkage:
00508           std::cerr << "Error: unmaterialized (GhostLinkage) function in asm!";
00509           abort();
00510         }
00511 
00512         emitAlignment(Align);
00513         O << name << ":\t\t\t\t; ";
00514         WriteAsOperand(O, I, true, true, &M);
00515         O << " = ";
00516         WriteAsOperand(O, C, false, false, &M);
00517         O << "\n";
00518         emitGlobalConstant(C);
00519       }
00520     }
00521 
00522   // Output stubs for dynamically-linked functions
00523   for (std::set<std::string>::iterator i = FnStubs.begin(), e = FnStubs.end(); 
00524        i != e; ++i)
00525   {
00526     O << ".data\n";
00527     O << ".section __TEXT,__picsymbolstub1,symbol_stubs,pure_instructions,32\n";
00528     emitAlignment(2);
00529     O << "L" << *i << "$stub:\n";
00530     O << "\t.indirect_symbol " << *i << "\n";
00531     O << "\tmflr r0\n";
00532     O << "\tbcl 20,31,L0$" << *i << "\n";
00533     O << "L0$" << *i << ":\n";
00534     O << "\tmflr r11\n";
00535     O << "\taddis r11,r11,ha16(L" << *i << "$lazy_ptr-L0$" << *i << ")\n";
00536     O << "\tmtlr r0\n";
00537     O << "\tlwzu r12,lo16(L" << *i << "$lazy_ptr-L0$" << *i << ")(r11)\n";
00538     O << "\tmtctr r12\n";
00539     O << "\tbctr\n";
00540     O << ".data\n";
00541     O << ".lazy_symbol_pointer\n";
00542     O << "L" << *i << "$lazy_ptr:\n";
00543     O << "\t.indirect_symbol " << *i << "\n";
00544     O << "\t.long dyld_stub_binding_helper\n";
00545   }
00546 
00547   O << "\n";
00548 
00549   // Output stubs for external global variables
00550   if (GVStubs.begin() != GVStubs.end())
00551     O << ".data\n.non_lazy_symbol_pointer\n";
00552   for (std::set<std::string>::iterator i = GVStubs.begin(), e = GVStubs.end(); 
00553        i != e; ++i) {
00554     O << "L" << *i << "$non_lazy_ptr:\n";
00555     O << "\t.indirect_symbol " << *i << "\n";
00556     O << "\t.long\t0\n";
00557   }
00558   
00559   // Output stubs for link-once variables
00560   if (LinkOnceStubs.begin() != LinkOnceStubs.end())
00561     O << ".data\n.align 2\n";
00562   for (std::set<std::string>::iterator i = LinkOnceStubs.begin(), 
00563          e = LinkOnceStubs.end(); i != e; ++i) {
00564     O << "L" << *i << "$non_lazy_ptr:\n"
00565       << "\t.long\t" << *i << '\n';
00566   }
00567   
00568   AsmPrinter::doFinalization(M);
00569   return false; // success
00570 }
00571 
00572 /// runOnMachineFunction - This uses the printMachineInstruction()
00573 /// method to print assembly for each instruction.
00574 ///
00575 bool AIXAsmPrinter::runOnMachineFunction(MachineFunction &MF) {
00576   CurrentFnName = MF.getFunction()->getName();
00577 
00578   // Print out constants referenced by the function
00579   printConstantPool(MF.getConstantPool());
00580 
00581   // Print out header for the function.
00582   O << "\t.csect .text[PR]\n"
00583     << "\t.align 2\n"
00584     << "\t.globl "  << CurrentFnName << '\n'
00585     << "\t.globl ." << CurrentFnName << '\n'
00586     << "\t.csect "  << CurrentFnName << "[DS],3\n"
00587     << CurrentFnName << ":\n"
00588     << "\t.llong ." << CurrentFnName << ", TOC[tc0], 0\n"
00589     << "\t.csect .text[PR]\n"
00590     << '.' << CurrentFnName << ":\n";
00591 
00592   // Print out code for the function.
00593   for (MachineFunction::const_iterator I = MF.begin(), E = MF.end();
00594        I != E; ++I) {
00595     // Print a label for the basic block.
00596     O << "LBB" << CurrentFnName << "_" << I->getNumber() << ":\t# "
00597       << I->getBasicBlock()->getName() << "\n";
00598     for (MachineBasicBlock::const_iterator II = I->begin(), E = I->end();
00599       II != E; ++II) {
00600       // Print the assembly for the instruction.
00601       O << "\t";
00602       printMachineInstruction(II);
00603     }
00604   }
00605   ++LabelNumber;
00606 
00607   O << "LT.." << CurrentFnName << ":\n"
00608     << "\t.long 0\n"
00609     << "\t.byte 0,0,32,65,128,0,0,0\n"
00610     << "\t.long LT.." << CurrentFnName << "-." << CurrentFnName << '\n'
00611     << "\t.short 3\n"
00612     << "\t.byte \"" << CurrentFnName << "\"\n"
00613     << "\t.align 2\n";
00614 
00615   // We didn't modify anything.
00616   return false;
00617 }
00618 
00619 /// printConstantPool - Print to the current output stream assembly
00620 /// representations of the constants in the constant pool MCP. This is
00621 /// used to print out constants which have been "spilled to memory" by
00622 /// the code generator.
00623 ///
00624 void AIXAsmPrinter::printConstantPool(MachineConstantPool *MCP) {
00625   const std::vector<Constant*> &CP = MCP->getConstants();
00626   const TargetData &TD = TM.getTargetData();
00627  
00628   if (CP.empty()) return;
00629 
00630   for (unsigned i = 0, e = CP.size(); i != e; ++i) {
00631     O << "\t.const\n";
00632     O << "\t.align " << (unsigned)TD.getTypeAlignment(CP[i]->getType())
00633       << "\n";
00634     O << ".CPI" << CurrentFnName << "_" << i << ":\t\t\t\t\t;"
00635       << *CP[i] << "\n";
00636     emitGlobalConstant(CP[i]);
00637   }
00638 }
00639 
00640 bool AIXAsmPrinter::doInitialization(Module &M) {
00641   const TargetData &TD = TM.getTargetData();
00642   std::string CurSection;
00643 
00644   O << "\t.machine \"ppc64\"\n" 
00645     << "\t.toc\n"
00646     << "\t.csect .text[PR]\n";
00647 
00648   // Print out module-level global variables
00649   for (Module::const_giterator I = M.gbegin(), E = M.gend(); I != E; ++I) {
00650     if (!I->hasInitializer())
00651       continue;
00652  
00653     std::string Name = I->getName();
00654     Constant *C = I->getInitializer();
00655     // N.B.: We are defaulting to writable strings
00656     if (I->hasExternalLinkage()) { 
00657       O << "\t.globl " << Name << '\n'
00658         << "\t.csect .data[RW],3\n";
00659     } else {
00660       O << "\t.csect _global.rw_c[RW],3\n";
00661     }
00662     O << Name << ":\n";
00663     emitGlobalConstant(C);
00664   }
00665 
00666   // Output labels for globals
00667   if (M.gbegin() != M.gend()) O << "\t.toc\n";
00668   for (Module::const_giterator I = M.gbegin(), E = M.gend(); I != E; ++I) {
00669     const GlobalVariable *GV = I;
00670     // Do not output labels for unused variables
00671     if (GV->isExternal() && GV->use_begin() == GV->use_end())
00672       continue;
00673 
00674     std::string Name = GV->getName();
00675     std::string Label = "LC.." + utostr(LabelNumber++);
00676     GVToLabelMap[GV] = Label;
00677     O << Label << ":\n"
00678       << "\t.tc " << Name << "[TC]," << Name;
00679     if (GV->isExternal()) O << "[RW]";
00680     O << '\n';
00681   }
00682 
00683   Mang = new Mangler(M, ".");
00684   return false; // success
00685 }
00686 
00687 bool AIXAsmPrinter::doFinalization(Module &M) {
00688   const TargetData &TD = TM.getTargetData();
00689   // Print out module-level global variables
00690   for (Module::const_giterator I = M.gbegin(), E = M.gend(); I != E; ++I) {
00691     if (I->hasInitializer() || I->hasExternalLinkage())
00692       continue;
00693 
00694     std::string Name = I->getName();
00695     if (I->hasInternalLinkage()) {
00696       O << "\t.lcomm " << Name << ",16,_global.bss_c";
00697     } else {
00698       O << "\t.comm " << Name << "," << TD.getTypeSize(I->getType())
00699         << "," << log2((unsigned)TD.getTypeAlignment(I->getType()));
00700     }
00701     O << "\t\t# ";
00702     WriteAsOperand(O, I, true, true, &M);
00703     O << "\n";
00704   }
00705 
00706   O << "_section_.text:\n"
00707     << "\t.csect .data[RW],3\n"
00708     << "\t.llong _section_.text\n";
00709 
00710   delete Mang;
00711   return false; // success
00712 }