llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp - toolchain/llvm-project - Gitiles

 //===-- PPCAsmPrinter.cpp - Print machine instrs to PowerPC assembly --------=//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file was developed by the LLVM research group and is distributed under
 // the University of Illinois Open Source License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 // This file contains a printer that converts from our internal representation
 // of machine-dependent LLVM code to PowerPC assembly language. This printer is
 // the output mechanism used by `llc'.
 //
 // Documentation at http://developer.apple.com/documentation/DeveloperTools/
 // Reference/Assembler/ASMIntroduction/chapter_1_section_1.html
 //
 //===----------------------------------------------------------------------===//

 #define DEBUG_TYPE "asmprinter"
 #include "PPC.h"
 #include "PPCTargetMachine.h"
 #include "PPCSubtarget.h"
 #include "llvm/Constants.h"
 #include "llvm/DerivedTypes.h"
 #include "llvm/Module.h"
 #include "llvm/Assembly/Writer.h"
 #include "llvm/CodeGen/AsmPrinter.h"
 #include "llvm/CodeGen/DwarfWriter.h"
 #include "llvm/CodeGen/MachineDebugInfo.h"
 #include "llvm/CodeGen/MachineFunctionPass.h"
 #include "llvm/CodeGen/MachineInstr.h"
 #include "llvm/Support/Mangler.h"
 #include "llvm/Support/MathExtras.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/Compiler.h"
 #include "llvm/Target/TargetAsmInfo.h"
 #include "llvm/Target/MRegisterInfo.h"
 #include "llvm/Target/TargetInstrInfo.h"
 #include "llvm/Target/TargetOptions.h"
 #include "llvm/ADT/Statistic.h"
 #include "llvm/ADT/StringExtras.h"
 #include <iostream>
 #include <set>
 using namespace llvm;

 namespace {
   Statistic<> EmittedInsts("asm-printer", "Number of machine instrs printed");

   struct VISIBILITY_HIDDEN PPCAsmPrinter : public AsmPrinter {
     std::set<std::string> FnStubs, GVStubs;
     const PPCSubtarget &Subtarget;

     PPCAsmPrinter(std::ostream &O, TargetMachine &TM, const TargetAsmInfo *T)
       : AsmPrinter(O, TM, T), Subtarget(TM.getSubtarget<PPCSubtarget>()) {
     }

     virtual const char *getPassName() const {
       return "PowerPC Assembly Printer";
     }

     PPCTargetMachine &getTM() {
       return static_cast<PPCTargetMachine&>(TM);
     }

     unsigned enumRegToMachineReg(unsigned enumReg) {
       switch (enumReg) {
       default: assert(0 && "Unhandled register!"); break;
       case PPC::CR0:  return  0;
       case PPC::CR1:  return  1;
       case PPC::CR2:  return  2;
       case PPC::CR3:  return  3;
       case PPC::CR4:  return  4;
       case PPC::CR5:  return  5;
       case PPC::CR6:  return  6;
       case PPC::CR7:  return  7;
       }
       abort();
     }

     /// printInstruction - This method is automatically generated by tablegen
     /// from the instruction set description.  This method returns true if the
     /// machine instruction was sufficiently described to print it, otherwise it
     /// returns false.
     bool printInstruction(const MachineInstr *MI);

     void printMachineInstruction(const MachineInstr *MI);
     void printOp(const MachineOperand &MO);

     void printOperand(const MachineInstr *MI, unsigned OpNo) {
       const MachineOperand &MO = MI->getOperand(OpNo);
       if (MO.isRegister()) {
         assert(MRegisterInfo::isPhysicalRegister(MO.getReg())&&"Not physreg??");
         O << TM.getRegisterInfo()->get(MO.getReg()).Name;
       } else if (MO.isImmediate()) {
         O << MO.getImmedValue();
       } else {
         printOp(MO);
       }
     }

     bool PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
                          unsigned AsmVariant, const char *ExtraCode);
     bool PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo,
                                unsigned AsmVariant, const char *ExtraCode);


     void printS5ImmOperand(const MachineInstr *MI, unsigned OpNo) {
       char value = MI->getOperand(OpNo).getImmedValue();
       value = (value << (32-5)) >> (32-5);
       O << (int)value;
     }
     void printU5ImmOperand(const MachineInstr *MI, unsigned OpNo) {
       unsigned char value = MI->getOperand(OpNo).getImmedValue();
       assert(value <= 31 && "Invalid u5imm argument!");
       O << (unsigned int)value;
     }
     void printU6ImmOperand(const MachineInstr *MI, unsigned OpNo) {
       unsigned char value = MI->getOperand(OpNo).getImmedValue();
       assert(value <= 63 && "Invalid u6imm argument!");
       O << (unsigned int)value;
     }
     void printS16ImmOperand(const MachineInstr *MI, unsigned OpNo) {
       O << (short)MI->getOperand(OpNo).getImmedValue();
     }
     void printU16ImmOperand(const MachineInstr *MI, unsigned OpNo) {
       O << (unsigned short)MI->getOperand(OpNo).getImmedValue();
     }
     void printS16X4ImmOperand(const MachineInstr *MI, unsigned OpNo) {
       O << (short)(MI->getOperand(OpNo).getImmedValue()*4);
     }
     void printBranchOperand(const MachineInstr *MI, unsigned OpNo) {
       // Branches can take an immediate operand.  This is used by the branch
       // selection pass to print $+8, an eight byte displacement from the PC.
       if (MI->getOperand(OpNo).isImmediate()) {
         O << "$+" << MI->getOperand(OpNo).getImmedValue()*4;
       } else {
         printOp(MI->getOperand(OpNo));
       }
     }
     void printCallOperand(const MachineInstr *MI, unsigned OpNo) {
       const MachineOperand &MO = MI->getOperand(OpNo);
       if (TM.getRelocationModel() != Reloc::Static) {
         if (MO.getType() == MachineOperand::MO_GlobalAddress) {
           GlobalValue *GV = MO.getGlobal();
           if (((GV->isExternal() || GV->hasWeakLinkage() ||
                 GV->hasLinkOnceLinkage()))) {
             // Dynamically-resolved functions need a stub for the function.
             std::string Name = Mang->getValueName(GV);
             FnStubs.insert(Name);
             O << "L" << Name << "$stub";
             return;
           }
         }
         if (MO.getType() == MachineOperand::MO_ExternalSymbol) {
           std::string Name(TAI->getGlobalPrefix()); Name += MO.getSymbolName();
           FnStubs.insert(Name);
           O << "L" << Name << "$stub";
           return;
         }
       }

       printOp(MI->getOperand(OpNo));
     }
     void printAbsAddrOperand(const MachineInstr *MI, unsigned OpNo) {
      O << (int)MI->getOperand(OpNo).getImmedValue()*4;
     }
     void printPICLabel(const MachineInstr *MI, unsigned OpNo) {
       O << "\"L" << getFunctionNumber() << "$pb\"\n";
       O << "\"L" << getFunctionNumber() << "$pb\":";
     }
     void printSymbolHi(const MachineInstr *MI, unsigned OpNo) {
       if (MI->getOperand(OpNo).isImmediate()) {
         printS16ImmOperand(MI, OpNo);
       } else {
         O << "ha16(";
         printOp(MI->getOperand(OpNo));
         if (TM.getRelocationModel() == Reloc::PIC_)
           O << "-\"L" << getFunctionNumber() << "$pb\")";
         else
           O << ')';
       }
     }
     void printSymbolLo(const MachineInstr *MI, unsigned OpNo) {
       if (MI->getOperand(OpNo).isImmediate()) {
         printS16ImmOperand(MI, OpNo);
       } else {
         O << "lo16(";
         printOp(MI->getOperand(OpNo));
         if (TM.getRelocationModel() == Reloc::PIC_)
           O << "-\"L" << getFunctionNumber() << "$pb\")";
         else
           O << ')';
       }
     }
     void printcrbitm(const MachineInstr *MI, unsigned OpNo) {
       unsigned CCReg = MI->getOperand(OpNo).getReg();
       unsigned RegNo = enumRegToMachineReg(CCReg);
       O << (0x80 >> RegNo);
     }
     // The new addressing mode printers.
     void printMemRegImm(const MachineInstr *MI, unsigned OpNo) {
       printSymbolLo(MI, OpNo);
       O << '(';
       if (MI->getOperand(OpNo+1).isRegister() &&
           MI->getOperand(OpNo+1).getReg() == PPC::R0)
         O << "0";
       else
         printOperand(MI, OpNo+1);
       O << ')';
     }
     void printMemRegImmShifted(const MachineInstr *MI, unsigned OpNo) {
       if (MI->getOperand(OpNo).isImmediate())
         printS16X4ImmOperand(MI, OpNo);
       else
         printSymbolLo(MI, OpNo);
       O << '(';
       if (MI->getOperand(OpNo+1).isRegister() &&
           MI->getOperand(OpNo+1).getReg() == PPC::R0)
         O << "0";
       else
         printOperand(MI, OpNo+1);
       O << ')';
     }

     void printMemRegReg(const MachineInstr *MI, unsigned OpNo) {
       // When used as the base register, r0 reads constant zero rather than
       // the value contained in the register.  For this reason, the darwin
       // assembler requires that we print r0 as 0 (no r) when used as the base.
       const MachineOperand &MO = MI->getOperand(OpNo);
       if (MO.getReg() == PPC::R0)
         O << '0';
       else
         O << TM.getRegisterInfo()->get(MO.getReg()).Name;
       O << ", ";
       printOperand(MI, OpNo+1);
     }

     virtual bool runOnMachineFunction(MachineFunction &F) = 0;
     virtual bool doFinalization(Module &M) = 0;

   };

   /// DarwinAsmPrinter - PowerPC assembly printer, customized for Darwin/Mac OS
   /// X
   struct VISIBILITY_HIDDEN DarwinAsmPrinter : public PPCAsmPrinter {

     DwarfWriter DW;

     DarwinAsmPrinter(std::ostream &O, PPCTargetMachine &TM,
                      const TargetAsmInfo *T)
       : PPCAsmPrinter(O, TM, T), DW(O, this, T) {
       bool isPPC64 = Subtarget.isPPC64();
     }

     virtual const char *getPassName() const {
       return "Darwin PPC Assembly Printer";
     }

     bool runOnMachineFunction(MachineFunction &F);
     bool doInitialization(Module &M);
     bool doFinalization(Module &M);

     void getAnalysisUsage(AnalysisUsage &AU) const {
       AU.setPreservesAll();
       AU.addRequired<MachineDebugInfo>();
       PPCAsmPrinter::getAnalysisUsage(AU);
     }

   };
 } // end of anonymous namespace

 // Include the auto-generated portion of the assembly writer
 #include "PPCGenAsmWriter.inc"

 void PPCAsmPrinter::printOp(const MachineOperand &MO) {
   switch (MO.getType()) {
   case MachineOperand::MO_Immediate:
     std::cerr << "printOp() does not handle immediate values\n";
     abort();
     return;

   case MachineOperand::MO_MachineBasicBlock:
     printBasicBlockLabel(MO.getMachineBasicBlock());
     return;
   case MachineOperand::MO_JumpTableIndex:
     O << TAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber()
       << '_' << MO.getJumpTableIndex();
     // FIXME: PIC relocation model
     return;
   case MachineOperand::MO_ConstantPoolIndex:
     O << TAI->getPrivateGlobalPrefix() << "CPI" << getFunctionNumber()
       << '_' << MO.getConstantPoolIndex();
     return;
   case MachineOperand::MO_ExternalSymbol:
     // Computing the address of an external symbol, not calling it.
     if (TM.getRelocationModel() != Reloc::Static) {
       std::string Name(TAI->getGlobalPrefix()); Name += MO.getSymbolName();
       GVStubs.insert(Name);
       O << "L" << Name << "$non_lazy_ptr";
       return;
     }
     O << TAI->getGlobalPrefix() << MO.getSymbolName();
     return;
   case MachineOperand::MO_GlobalAddress: {
     // Computing the address of a global symbol, not calling it.
     GlobalValue *GV = MO.getGlobal();
     std::string Name = Mang->getValueName(GV);
     int offset = MO.getOffset();

     // External or weakly linked global variables need non-lazily-resolved stubs
     if (TM.getRelocationModel() != Reloc::Static) {
       if (((GV->isExternal() || GV->hasWeakLinkage() ||
             GV->hasLinkOnceLinkage()))) {
         GVStubs.insert(Name);
         O << "L" << Name << "$non_lazy_ptr";
         return;
       }
     }

     O << Name;
     return;
   }

   default:
     O << "<unknown operand type: " << MO.getType() << ">";
     return;
   }
 }

 /// PrintAsmOperand - Print out an operand for an inline asm expression.
 ///
 bool PPCAsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
                                     unsigned AsmVariant,
                                     const char *ExtraCode) {
   // Does this asm operand have a single letter operand modifier?
   if (ExtraCode && ExtraCode[0]) {
     if (ExtraCode[1] != 0) return true; // Unknown modifier.

     switch (ExtraCode[0]) {
     default: return true;  // Unknown modifier.
     case 'L': // Write second word of DImode reference.
       // Verify that this operand has two consecutive registers.
       if (!MI->getOperand(OpNo).isRegister() ||
           OpNo+1 == MI->getNumOperands() ||
           !MI->getOperand(OpNo+1).isRegister())
         return true;
       ++OpNo;   // Return the high-part.
       break;
     }
   }

   printOperand(MI, OpNo);
   return false;
 }

 bool PPCAsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo,
                                           unsigned AsmVariant,
                                           const char *ExtraCode) {
   if (ExtraCode && ExtraCode[0])
     return true; // Unknown modifier.
   printMemRegReg(MI, OpNo);
   return false;
 }

 /// printMachineInstruction -- Print out a single PowerPC MI in Darwin syntax to
 /// the current output stream.
 ///
 void PPCAsmPrinter::printMachineInstruction(const MachineInstr *MI) {
   ++EmittedInsts;

   // Check for slwi/srwi mnemonics.
   if (MI->getOpcode() == PPC::RLWINM) {
     bool FoundMnemonic = false;
     unsigned char SH = MI->getOperand(2).getImmedValue();
     unsigned char MB = MI->getOperand(3).getImmedValue();
     unsigned char ME = MI->getOperand(4).getImmedValue();
     if (SH <= 31 && MB == 0 && ME == (31-SH)) {
       O << "slwi "; FoundMnemonic = true;
     }
     if (SH <= 31 && MB == (32-SH) && ME == 31) {
       O << "srwi "; FoundMnemonic = true;
       SH = 32-SH;
     }
     if (FoundMnemonic) {
       printOperand(MI, 0);
       O << ", ";
       printOperand(MI, 1);
       O << ", " << (unsigned int)SH << "\n";
       return;
     }
   } else if (MI->getOpcode() == PPC::OR || MI->getOpcode() == PPC::OR8) {
     if (MI->getOperand(1).getReg() == MI->getOperand(2).getReg()) {
       O << "mr ";
       printOperand(MI, 0);
       O << ", ";
       printOperand(MI, 1);
       O << "\n";
       return;
     }
   }

   if (printInstruction(MI))
     return; // Printer was automatically generated

   assert(0 && "Unhandled instruction in asm writer!");
   abort();
   return;
 }

 /// runOnMachineFunction - This uses the printMachineInstruction()
 /// method to print assembly for each instruction.
 ///
 bool DarwinAsmPrinter::runOnMachineFunction(MachineFunction &MF) {
   DW.SetDebugInfo(&getAnalysis<MachineDebugInfo>());

   SetupMachineFunction(MF);
   O << "\n\n";

   // Print out constants referenced by the function
   EmitConstantPool(MF.getConstantPool());

   // Print out jump tables referenced by the function
   EmitJumpTableInfo(MF.getJumpTableInfo());

   // Print out labels for the function.
   const Function *F = MF.getFunction();
   switch (F->getLinkage()) {
   default: assert(0 && "Unknown linkage type!");
   case Function::InternalLinkage:  // Symbols default to internal.
     SwitchToTextSection("\t.text", F);
     break;
   case Function::ExternalLinkage:
     SwitchToTextSection("\t.text", F);
     O << "\t.globl\t" << CurrentFnName << "\n";
     break;
   case Function::WeakLinkage:
   case Function::LinkOnceLinkage:
     SwitchToTextSection(
                 ".section __TEXT,__textcoal_nt,coalesced,pure_instructions", F);
     O << "\t.globl\t" << CurrentFnName << "\n";
     O << "\t.weak_definition\t" << CurrentFnName << "\n";
     break;
   }
   EmitAlignment(4, F);
   O << CurrentFnName << ":\n";

   // Emit pre-function debug information.
   DW.BeginFunction(&MF);

   // Print out code for the function.
   for (MachineFunction::const_iterator I = MF.begin(), E = MF.end();
        I != E; ++I) {
     // Print a label for the basic block.
     if (I != MF.begin()) {
       printBasicBlockLabel(I, true);
       O << '\n';
     }
     for (MachineBasicBlock::const_iterator II = I->begin(), E = I->end();
          II != E; ++II) {
       // Print the assembly for the instruction.
       O << "\t";
       printMachineInstruction(II);
     }
   }

   // Emit post-function debug information.
   DW.EndFunction();

   // We didn't modify anything.
   return false;
 }


 bool DarwinAsmPrinter::doInitialization(Module &M) {
   if (Subtarget.isGigaProcessor())
     O << "\t.machine ppc970\n";
   AsmPrinter::doInitialization(M);

   // Darwin wants symbols to be quoted if they have complex names.
   Mang->setUseQuotes(true);

   // Emit initial debug information.
   DW.BeginModule(&M);
   return false;
 }

 bool DarwinAsmPrinter::doFinalization(Module &M) {
   const TargetData *TD = TM.getTargetData();

   // Print out module-level global variables here.
   for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
        I != E; ++I) {
     if (!I->hasInitializer()) continue;   // External global require no code

     // Check to see if this is a special global used by LLVM, if so, emit it.
     if (EmitSpecialLLVMGlobal(I))
       continue;

     std::string name = Mang->getValueName(I);
     Constant *C = I->getInitializer();
     unsigned Size = TD->getTypeSize(C->getType());
     unsigned Align = getPreferredAlignmentLog(I);

     if (C->isNullValue() && /* FIXME: Verify correct */
         (I->hasInternalLinkage() || I->hasWeakLinkage() ||
          I->hasLinkOnceLinkage() ||
          (I->hasExternalLinkage() && !I->hasSection()))) {
       if (Size == 0) Size = 1;   // .comm Foo, 0 is undefined, avoid it.
       if (I->hasExternalLinkage()) {
         O << "\t.globl " << name << '\n';
         O << "\t.zerofill __DATA, __common, " << name << ", "
           << Size << ", " << Align;
       } else if (I->hasInternalLinkage()) {
         SwitchToDataSection("\t.data", I);
         O << TAI->getLCOMMDirective() << name << "," << Size << "," << Align;
       } else {
         SwitchToDataSection("\t.data", I);
         O << ".comm " << name << "," << Size;
       }
       O << "\t\t; '" << I->getName() << "'\n";
     } else {
       switch (I->getLinkage()) {
       case GlobalValue::LinkOnceLinkage:
       case GlobalValue::WeakLinkage:
         O << "\t.globl " << name << '\n'
           << "\t.weak_definition " << name << '\n';
         SwitchToDataSection(".section __DATA,__datacoal_nt,coalesced", I);
         break;
       case GlobalValue::AppendingLinkage:
         // FIXME: appending linkage variables should go into a section of
         // their name or something.  For now, just emit them as external.
       case GlobalValue::ExternalLinkage:
         // If external or appending, declare as a global symbol
         O << "\t.globl " << name << "\n";
         // FALL THROUGH
       case GlobalValue::InternalLinkage:
         SwitchToDataSection("\t.data", I);
         break;
       default:
         std::cerr << "Unknown linkage type!";
         abort();
       }

       EmitAlignment(Align, I);
       O << name << ":\t\t\t\t; '" << I->getName() << "'\n";
       EmitGlobalConstant(C);
       O << '\n';
     }
   }

   bool isPPC64 = TD->getPointerSizeInBits() == 64;

   // Output stubs for dynamically-linked functions
   if (TM.getRelocationModel() == Reloc::PIC_) {
     for (std::set<std::string>::iterator i = FnStubs.begin(), e = FnStubs.end();
          i != e; ++i) {
       SwitchToTextSection(".section __TEXT,__picsymbolstub1,symbol_stubs,"
                           "pure_instructions,32", 0);
       EmitAlignment(4);
       O << "L" << *i << "$stub:\n";
       O << "\t.indirect_symbol " << *i << "\n";
       O << "\tmflr r0\n";
       O << "\tbcl 20,31,L0$" << *i << "\n";
       O << "L0$" << *i << ":\n";
       O << "\tmflr r11\n";
       O << "\taddis r11,r11,ha16(L" << *i << "$lazy_ptr-L0$" << *i << ")\n";
       O << "\tmtlr r0\n";
       if (isPPC64)
         O << "\tldu r12,lo16(L" << *i << "$lazy_ptr-L0$" << *i << ")(r11)\n";
       else
         O << "\tlwzu r12,lo16(L" << *i << "$lazy_ptr-L0$" << *i << ")(r11)\n";
       O << "\tmtctr r12\n";
       O << "\tbctr\n";
       SwitchToDataSection(".lazy_symbol_pointer", 0);
       O << "L" << *i << "$lazy_ptr:\n";
       O << "\t.indirect_symbol " << *i << "\n";
       if (isPPC64)
         O << "\t.quad dyld_stub_binding_helper\n";
       else
         O << "\t.long dyld_stub_binding_helper\n";
     }
   } else {
     for (std::set<std::string>::iterator i = FnStubs.begin(), e = FnStubs.end();
          i != e; ++i) {
       SwitchToTextSection(".section __TEXT,__symbol_stub1,symbol_stubs,"
                           "pure_instructions,16", 0);
       EmitAlignment(4);
       O << "L" << *i << "$stub:\n";
       O << "\t.indirect_symbol " << *i << "\n";
       O << "\tlis r11,ha16(L" << *i << "$lazy_ptr)\n";
       if (isPPC64)
         O << "\tldu r12,lo16(L" << *i << "$lazy_ptr)(r11)\n";
       else
         O << "\tlwzu r12,lo16(L" << *i << "$lazy_ptr)(r11)\n";
       O << "\tmtctr r12\n";
       O << "\tbctr\n";
       SwitchToDataSection(".lazy_symbol_pointer", 0);
       O << "L" << *i << "$lazy_ptr:\n";
       O << "\t.indirect_symbol " << *i << "\n";
       if (isPPC64)
         O << "\t.quad dyld_stub_binding_helper\n";
       else
         O << "\t.long dyld_stub_binding_helper\n";
     }
   }

   O << "\n";

   // Output stubs for external and common global variables.
   if (GVStubs.begin() != GVStubs.end()) {
     SwitchToDataSection(".non_lazy_symbol_pointer", 0);
     for (std::set<std::string>::iterator I = GVStubs.begin(),
          E = GVStubs.end(); I != E; ++I) {
       O << "L" << *I << "$non_lazy_ptr:\n";
       O << "\t.indirect_symbol " << *I << "\n";
       if (isPPC64)
         O << "\t.quad\t0\n";
       else
         O << "\t.long\t0\n";

     }
   }

   // Emit initial debug information.
   DW.EndModule();

   // Funny Darwin hack: This flag tells the linker that no global symbols
   // contain code that falls through to other global symbols (e.g. the obvious
   // implementation of multiple entry points).  If this doesn't occur, the
   // linker can safely perform dead code stripping.  Since LLVM never generates
   // code that does this, it is always safe to set.
   O << "\t.subsections_via_symbols\n";

   AsmPrinter::doFinalization(M);
   return false; // success
 }


 /// createDarwinCodePrinterPass - Returns a pass that prints the PPC assembly
 /// code for a MachineFunction to the given output stream, in a format that the
 /// Darwin assembler can deal with.
 ///
 FunctionPass *llvm::createPPCAsmPrinterPass(std::ostream &o,
                                             PPCTargetMachine &tm) {
   return new DarwinAsmPrinter(o, tm, tm.getTargetAsmInfo());
 }
	//===-- PPCAsmPrinter.cpp - Print machine instrs to PowerPC assembly --------=//
	//
	// The LLVM Compiler Infrastructure
	//
	// This file was developed by the LLVM research group and is distributed under
	// the University of Illinois Open Source License. See LICENSE.TXT for details.
	//
	//===----------------------------------------------------------------------===//
	//
	// This file contains a printer that converts from our internal representation
	// of machine-dependent LLVM code to PowerPC assembly language. This printer is
	// the output mechanism used by `llc'.
	//
	// Documentation at http://developer.apple.com/documentation/DeveloperTools/
	// Reference/Assembler/ASMIntroduction/chapter_1_section_1.html
	//
	//===----------------------------------------------------------------------===//

	#define DEBUG_TYPE "asmprinter"
	#include "PPC.h"
	#include "PPCTargetMachine.h"
	#include "PPCSubtarget.h"
	#include "llvm/Constants.h"
	#include "llvm/DerivedTypes.h"
	#include "llvm/Module.h"
	#include "llvm/Assembly/Writer.h"
	#include "llvm/CodeGen/AsmPrinter.h"
	#include "llvm/CodeGen/DwarfWriter.h"
	#include "llvm/CodeGen/MachineDebugInfo.h"
	#include "llvm/CodeGen/MachineFunctionPass.h"
	#include "llvm/CodeGen/MachineInstr.h"
	#include "llvm/Support/Mangler.h"
	#include "llvm/Support/MathExtras.h"
	#include "llvm/Support/CommandLine.h"
	#include "llvm/Support/Debug.h"
	#include "llvm/Support/Compiler.h"
	#include "llvm/Target/TargetAsmInfo.h"
	#include "llvm/Target/MRegisterInfo.h"
	#include "llvm/Target/TargetInstrInfo.h"
	#include "llvm/Target/TargetOptions.h"
	#include "llvm/ADT/Statistic.h"
	#include "llvm/ADT/StringExtras.h"
	#include <iostream>
	#include <set>
	using namespace llvm;

	namespace {
	Statistic<> EmittedInsts("asm-printer", "Number of machine instrs printed");

	struct VISIBILITY_HIDDEN PPCAsmPrinter : public AsmPrinter {
	std::set<std::string> FnStubs, GVStubs;
	const PPCSubtarget &Subtarget;

	PPCAsmPrinter(std::ostream &O, TargetMachine &TM, const TargetAsmInfo *T)
	: AsmPrinter(O, TM, T), Subtarget(TM.getSubtarget<PPCSubtarget>()) {
	}

	virtual const char *getPassName() const {
	return "PowerPC Assembly Printer";
	}

	PPCTargetMachine &getTM() {
	return static_cast<PPCTargetMachine&>(TM);
	}

	unsigned enumRegToMachineReg(unsigned enumReg) {
	switch (enumReg) {
	default: assert(0 && "Unhandled register!"); break;
	case PPC::CR0: return 0;
	case PPC::CR1: return 1;
	case PPC::CR2: return 2;
	case PPC::CR3: return 3;
	case PPC::CR4: return 4;
	case PPC::CR5: return 5;
	case PPC::CR6: return 6;
	case PPC::CR7: return 7;
	}
	abort();
	}

	/// printInstruction - This method is automatically generated by tablegen
	/// from the instruction set description. This method returns true if the
	/// machine instruction was sufficiently described to print it, otherwise it
	/// returns false.
	bool printInstruction(const MachineInstr *MI);

	void printMachineInstruction(const MachineInstr *MI);
	void printOp(const MachineOperand &MO);

	void printOperand(const MachineInstr *MI, unsigned OpNo) {
	const MachineOperand &MO = MI->getOperand(OpNo);
	if (MO.isRegister()) {
	assert(MRegisterInfo::isPhysicalRegister(MO.getReg())&&"Not physreg??");
	O << TM.getRegisterInfo()->get(MO.getReg()).Name;
	} else if (MO.isImmediate()) {
	O << MO.getImmedValue();
	} else {
	printOp(MO);
	}
	}

	bool PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
	unsigned AsmVariant, const char *ExtraCode);
	bool PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo,
	unsigned AsmVariant, const char *ExtraCode);


	void printS5ImmOperand(const MachineInstr *MI, unsigned OpNo) {
	char value = MI->getOperand(OpNo).getImmedValue();
	value = (value << (32-5)) >> (32-5);
	O << (int)value;
	}
	void printU5ImmOperand(const MachineInstr *MI, unsigned OpNo) {
	unsigned char value = MI->getOperand(OpNo).getImmedValue();
	assert(value <= 31 && "Invalid u5imm argument!");
	O << (unsigned int)value;
	}
	void printU6ImmOperand(const MachineInstr *MI, unsigned OpNo) {
	unsigned char value = MI->getOperand(OpNo).getImmedValue();
	assert(value <= 63 && "Invalid u6imm argument!");
	O << (unsigned int)value;
	}
	void printS16ImmOperand(const MachineInstr *MI, unsigned OpNo) {
	O << (short)MI->getOperand(OpNo).getImmedValue();
	}
	void printU16ImmOperand(const MachineInstr *MI, unsigned OpNo) {
	O << (unsigned short)MI->getOperand(OpNo).getImmedValue();
	}
	void printS16X4ImmOperand(const MachineInstr *MI, unsigned OpNo) {
	O << (short)(MI->getOperand(OpNo).getImmedValue()*4);
	}
	void printBranchOperand(const MachineInstr *MI, unsigned OpNo) {
	// Branches can take an immediate operand. This is used by the branch
	// selection pass to print $+8, an eight byte displacement from the PC.
	if (MI->getOperand(OpNo).isImmediate()) {
	O << "$+" << MI->getOperand(OpNo).getImmedValue()*4;
	} else {
	printOp(MI->getOperand(OpNo));
	}
	}
	void printCallOperand(const MachineInstr *MI, unsigned OpNo) {
	const MachineOperand &MO = MI->getOperand(OpNo);
	if (TM.getRelocationModel() != Reloc::Static) {
	if (MO.getType() == MachineOperand::MO_GlobalAddress) {
	GlobalValue *GV = MO.getGlobal();
	if (((GV->isExternal() \|\| GV->hasWeakLinkage() \|\|
	GV->hasLinkOnceLinkage()))) {
	// Dynamically-resolved functions need a stub for the function.
	std::string Name = Mang->getValueName(GV);
	FnStubs.insert(Name);
	O << "L" << Name << "$stub";
	return;
	}
	}
	if (MO.getType() == MachineOperand::MO_ExternalSymbol) {
	std::string Name(TAI->getGlobalPrefix()); Name += MO.getSymbolName();
	FnStubs.insert(Name);
	O << "L" << Name << "$stub";
	return;
	}
	}

	printOp(MI->getOperand(OpNo));
	}
	void printAbsAddrOperand(const MachineInstr *MI, unsigned OpNo) {
	O << (int)MI->getOperand(OpNo).getImmedValue()*4;
	}
	void printPICLabel(const MachineInstr *MI, unsigned OpNo) {
	O << "\"L" << getFunctionNumber() << "$pb\"\n";
	O << "\"L" << getFunctionNumber() << "$pb\":";
	}
	void printSymbolHi(const MachineInstr *MI, unsigned OpNo) {
	if (MI->getOperand(OpNo).isImmediate()) {
	printS16ImmOperand(MI, OpNo);
	} else {
	O << "ha16(";
	printOp(MI->getOperand(OpNo));
	if (TM.getRelocationModel() == Reloc::PIC_)
	O << "-\"L" << getFunctionNumber() << "$pb\")";
	else
	O << ')';
	}
	}
	void printSymbolLo(const MachineInstr *MI, unsigned OpNo) {
	if (MI->getOperand(OpNo).isImmediate()) {
	printS16ImmOperand(MI, OpNo);
	} else {
	O << "lo16(";
	printOp(MI->getOperand(OpNo));
	if (TM.getRelocationModel() == Reloc::PIC_)
	O << "-\"L" << getFunctionNumber() << "$pb\")";
	else
	O << ')';
	}
	}
	void printcrbitm(const MachineInstr *MI, unsigned OpNo) {
	unsigned CCReg = MI->getOperand(OpNo).getReg();
	unsigned RegNo = enumRegToMachineReg(CCReg);
	O << (0x80 >> RegNo);
	}
	// The new addressing mode printers.
	void printMemRegImm(const MachineInstr *MI, unsigned OpNo) {
	printSymbolLo(MI, OpNo);
	O << '(';
	if (MI->getOperand(OpNo+1).isRegister() &&
	MI->getOperand(OpNo+1).getReg() == PPC::R0)
	O << "0";
	else
	printOperand(MI, OpNo+1);
	O << ')';
	}
	void printMemRegImmShifted(const MachineInstr *MI, unsigned OpNo) {
	if (MI->getOperand(OpNo).isImmediate())
	printS16X4ImmOperand(MI, OpNo);
	else
	printSymbolLo(MI, OpNo);
	O << '(';
	if (MI->getOperand(OpNo+1).isRegister() &&
	MI->getOperand(OpNo+1).getReg() == PPC::R0)
	O << "0";
	else
	printOperand(MI, OpNo+1);
	O << ')';
	}

	void printMemRegReg(const MachineInstr *MI, unsigned OpNo) {
	// When used as the base register, r0 reads constant zero rather than
	// the value contained in the register. For this reason, the darwin
	// assembler requires that we print r0 as 0 (no r) when used as the base.
	const MachineOperand &MO = MI->getOperand(OpNo);
	if (MO.getReg() == PPC::R0)
	O << '0';
	else
	O << TM.getRegisterInfo()->get(MO.getReg()).Name;
	O << ", ";
	printOperand(MI, OpNo+1);
	}

	virtual bool runOnMachineFunction(MachineFunction &F) = 0;
	virtual bool doFinalization(Module &M) = 0;

	};

	/// DarwinAsmPrinter - PowerPC assembly printer, customized for Darwin/Mac OS
	/// X
	struct VISIBILITY_HIDDEN DarwinAsmPrinter : public PPCAsmPrinter {

	DwarfWriter DW;

	DarwinAsmPrinter(std::ostream &O, PPCTargetMachine &TM,
	const TargetAsmInfo *T)
	: PPCAsmPrinter(O, TM, T), DW(O, this, T) {
	bool isPPC64 = Subtarget.isPPC64();
	}

	virtual const char *getPassName() const {
	return "Darwin PPC Assembly Printer";
	}

	bool runOnMachineFunction(MachineFunction &F);
	bool doInitialization(Module &M);
	bool doFinalization(Module &M);

	void getAnalysisUsage(AnalysisUsage &AU) const {
	AU.setPreservesAll();
	AU.addRequired<MachineDebugInfo>();
	PPCAsmPrinter::getAnalysisUsage(AU);
	}

	};
	} // end of anonymous namespace

	// Include the auto-generated portion of the assembly writer
	#include "PPCGenAsmWriter.inc"

	void PPCAsmPrinter::printOp(const MachineOperand &MO) {
	switch (MO.getType()) {
	case MachineOperand::MO_Immediate:
	std::cerr << "printOp() does not handle immediate values\n";
	abort();
	return;

	case MachineOperand::MO_MachineBasicBlock:
	printBasicBlockLabel(MO.getMachineBasicBlock());
	return;
	case MachineOperand::MO_JumpTableIndex:
	O << TAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber()
	<< '_' << MO.getJumpTableIndex();
	// FIXME: PIC relocation model
	return;
	case MachineOperand::MO_ConstantPoolIndex:
	O << TAI->getPrivateGlobalPrefix() << "CPI" << getFunctionNumber()
	<< '_' << MO.getConstantPoolIndex();
	return;
	case MachineOperand::MO_ExternalSymbol:
	// Computing the address of an external symbol, not calling it.
	if (TM.getRelocationModel() != Reloc::Static) {
	std::string Name(TAI->getGlobalPrefix()); Name += MO.getSymbolName();
	GVStubs.insert(Name);
	O << "L" << Name << "$non_lazy_ptr";
	return;
	}
	O << TAI->getGlobalPrefix() << MO.getSymbolName();
	return;
	case MachineOperand::MO_GlobalAddress: {
	// Computing the address of a global symbol, not calling it.
	GlobalValue *GV = MO.getGlobal();
	std::string Name = Mang->getValueName(GV);
	int offset = MO.getOffset();

	// External or weakly linked global variables need non-lazily-resolved stubs
	if (TM.getRelocationModel() != Reloc::Static) {
	if (((GV->isExternal() \|\| GV->hasWeakLinkage() \|\|
	GV->hasLinkOnceLinkage()))) {
	GVStubs.insert(Name);
	O << "L" << Name << "$non_lazy_ptr";
	return;
	}
	}

	O << Name;
	return;
	}

	default:
	O << "<unknown operand type: " << MO.getType() << ">";
	return;
	}
	}

	/// PrintAsmOperand - Print out an operand for an inline asm expression.
	///
	bool PPCAsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
	unsigned AsmVariant,
	const char *ExtraCode) {
	// Does this asm operand have a single letter operand modifier?
	if (ExtraCode && ExtraCode[0]) {
	if (ExtraCode[1] != 0) return true; // Unknown modifier.

	switch (ExtraCode[0]) {
	default: return true; // Unknown modifier.
	case 'L': // Write second word of DImode reference.
	// Verify that this operand has two consecutive registers.
	if (!MI->getOperand(OpNo).isRegister() \|\|
	OpNo+1 == MI->getNumOperands() \|\|
	!MI->getOperand(OpNo+1).isRegister())
	return true;
	++OpNo; // Return the high-part.
	break;
	}
	}

	printOperand(MI, OpNo);
	return false;
	}

	bool PPCAsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo,
	unsigned AsmVariant,
	const char *ExtraCode) {
	if (ExtraCode && ExtraCode[0])
	return true; // Unknown modifier.
	printMemRegReg(MI, OpNo);
	return false;
	}

	/// printMachineInstruction -- Print out a single PowerPC MI in Darwin syntax to
	/// the current output stream.
	///
	void PPCAsmPrinter::printMachineInstruction(const MachineInstr *MI) {
	++EmittedInsts;

	// Check for slwi/srwi mnemonics.
	if (MI->getOpcode() == PPC::RLWINM) {
	bool FoundMnemonic = false;
	unsigned char SH = MI->getOperand(2).getImmedValue();
	unsigned char MB = MI->getOperand(3).getImmedValue();
	unsigned char ME = MI->getOperand(4).getImmedValue();
	if (SH <= 31 && MB == 0 && ME == (31-SH)) {
	O << "slwi "; FoundMnemonic = true;
	}
	if (SH <= 31 && MB == (32-SH) && ME == 31) {
	O << "srwi "; FoundMnemonic = true;
	SH = 32-SH;
	}
	if (FoundMnemonic) {
	printOperand(MI, 0);
	O << ", ";
	printOperand(MI, 1);
	O << ", " << (unsigned int)SH << "\n";
	return;
	}
	} else if (MI->getOpcode() == PPC::OR \|\| MI->getOpcode() == PPC::OR8) {
	if (MI->getOperand(1).getReg() == MI->getOperand(2).getReg()) {
	O << "mr ";
	printOperand(MI, 0);
	O << ", ";
	printOperand(MI, 1);
	O << "\n";
	return;
	}
	}

	if (printInstruction(MI))
	return; // Printer was automatically generated

	assert(0 && "Unhandled instruction in asm writer!");
	abort();
	return;
	}

	/// runOnMachineFunction - This uses the printMachineInstruction()
	/// method to print assembly for each instruction.
	///
	bool DarwinAsmPrinter::runOnMachineFunction(MachineFunction &MF) {
	DW.SetDebugInfo(&getAnalysis<MachineDebugInfo>());

	SetupMachineFunction(MF);
	O << "\n\n";

	// Print out constants referenced by the function
	EmitConstantPool(MF.getConstantPool());

	// Print out jump tables referenced by the function
	EmitJumpTableInfo(MF.getJumpTableInfo());

	// Print out labels for the function.
	const Function *F = MF.getFunction();
	switch (F->getLinkage()) {
	default: assert(0 && "Unknown linkage type!");
	case Function::InternalLinkage: // Symbols default to internal.
	SwitchToTextSection("\t.text", F);
	break;
	case Function::ExternalLinkage:
	SwitchToTextSection("\t.text", F);
	O << "\t.globl\t" << CurrentFnName << "\n";
	break;
	case Function::WeakLinkage:
	case Function::LinkOnceLinkage:
	SwitchToTextSection(
	".section __TEXT,__textcoal_nt,coalesced,pure_instructions", F);
	O << "\t.globl\t" << CurrentFnName << "\n";
	O << "\t.weak_definition\t" << CurrentFnName << "\n";
	break;
	}
	EmitAlignment(4, F);
	O << CurrentFnName << ":\n";

	// Emit pre-function debug information.
	DW.BeginFunction(&MF);

	// Print out code for the function.
	for (MachineFunction::const_iterator I = MF.begin(), E = MF.end();
	I != E; ++I) {
	// Print a label for the basic block.
	if (I != MF.begin()) {
	printBasicBlockLabel(I, true);
	O << '\n';
	}
	for (MachineBasicBlock::const_iterator II = I->begin(), E = I->end();
	II != E; ++II) {
	// Print the assembly for the instruction.
	O << "\t";
	printMachineInstruction(II);
	}
	}

	// Emit post-function debug information.
	DW.EndFunction();

	// We didn't modify anything.
	return false;
	}


	bool DarwinAsmPrinter::doInitialization(Module &M) {
	if (Subtarget.isGigaProcessor())
	O << "\t.machine ppc970\n";
	AsmPrinter::doInitialization(M);

	// Darwin wants symbols to be quoted if they have complex names.
	Mang->setUseQuotes(true);

	// Emit initial debug information.
	DW.BeginModule(&M);
	return false;
	}

	bool DarwinAsmPrinter::doFinalization(Module &M) {
	const TargetData *TD = TM.getTargetData();

	// Print out module-level global variables here.
	for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
	I != E; ++I) {
	if (!I->hasInitializer()) continue; // External global require no code

	// Check to see if this is a special global used by LLVM, if so, emit it.
	if (EmitSpecialLLVMGlobal(I))
	continue;

	std::string name = Mang->getValueName(I);
	Constant *C = I->getInitializer();
	unsigned Size = TD->getTypeSize(C->getType());
	unsigned Align = getPreferredAlignmentLog(I);

	if (C->isNullValue() && /* FIXME: Verify correct */
	(I->hasInternalLinkage() \|\| I->hasWeakLinkage() \|\|
	I->hasLinkOnceLinkage() \|\|
	(I->hasExternalLinkage() && !I->hasSection()))) {
	if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
	if (I->hasExternalLinkage()) {
	O << "\t.globl " << name << '\n';
	O << "\t.zerofill __DATA, __common, " << name << ", "
	<< Size << ", " << Align;
	} else if (I->hasInternalLinkage()) {
	SwitchToDataSection("\t.data", I);
	O << TAI->getLCOMMDirective() << name << "," << Size << "," << Align;
	} else {
	SwitchToDataSection("\t.data", I);
	O << ".comm " << name << "," << Size;
	}
	O << "\t\t; '" << I->getName() << "'\n";
	} else {
	switch (I->getLinkage()) {
	case GlobalValue::LinkOnceLinkage:
	case GlobalValue::WeakLinkage:
	O << "\t.globl " << name << '\n'
	<< "\t.weak_definition " << name << '\n';
	SwitchToDataSection(".section __DATA,__datacoal_nt,coalesced", I);
	break;
	case GlobalValue::AppendingLinkage:
	// FIXME: appending linkage variables should go into a section of
	// their name or something. For now, just emit them as external.
	case GlobalValue::ExternalLinkage:
	// If external or appending, declare as a global symbol
	O << "\t.globl " << name << "\n";
	// FALL THROUGH
	case GlobalValue::InternalLinkage:
	SwitchToDataSection("\t.data", I);
	break;
	default:
	std::cerr << "Unknown linkage type!";
	abort();
	}

	EmitAlignment(Align, I);
	O << name << ":\t\t\t\t; '" << I->getName() << "'\n";
	EmitGlobalConstant(C);
	O << '\n';
	}
	}

	bool isPPC64 = TD->getPointerSizeInBits() == 64;

	// Output stubs for dynamically-linked functions
	if (TM.getRelocationModel() == Reloc::PIC_) {
	for (std::set<std::string>::iterator i = FnStubs.begin(), e = FnStubs.end();
	i != e; ++i) {
	SwitchToTextSection(".section __TEXT,__picsymbolstub1,symbol_stubs,"
	"pure_instructions,32", 0);
	EmitAlignment(4);
	O << "L" << *i << "$stub:\n";
	O << "\t.indirect_symbol " << *i << "\n";
	O << "\tmflr r0\n";
	O << "\tbcl 20,31,L0$" << *i << "\n";
	O << "L0$" << *i << ":\n";
	O << "\tmflr r11\n";
	O << "\taddis r11,r11,ha16(L" << i << "$lazy_ptr-L0$" << i << ")\n";
	O << "\tmtlr r0\n";
	if (isPPC64)
	O << "\tldu r12,lo16(L" << i << "$lazy_ptr-L0$" << i << ")(r11)\n";
	else
	O << "\tlwzu r12,lo16(L" << i << "$lazy_ptr-L0$" << i << ")(r11)\n";
	O << "\tmtctr r12\n";
	O << "\tbctr\n";
	SwitchToDataSection(".lazy_symbol_pointer", 0);
	O << "L" << *i << "$lazy_ptr:\n";
	O << "\t.indirect_symbol " << *i << "\n";
	if (isPPC64)
	O << "\t.quad dyld_stub_binding_helper\n";
	else
	O << "\t.long dyld_stub_binding_helper\n";
	}
	} else {
	for (std::set<std::string>::iterator i = FnStubs.begin(), e = FnStubs.end();
	i != e; ++i) {
	SwitchToTextSection(".section __TEXT,__symbol_stub1,symbol_stubs,"
	"pure_instructions,16", 0);
	EmitAlignment(4);
	O << "L" << *i << "$stub:\n";
	O << "\t.indirect_symbol " << *i << "\n";
	O << "\tlis r11,ha16(L" << *i << "$lazy_ptr)\n";
	if (isPPC64)
	O << "\tldu r12,lo16(L" << *i << "$lazy_ptr)(r11)\n";
	else
	O << "\tlwzu r12,lo16(L" << *i << "$lazy_ptr)(r11)\n";
	O << "\tmtctr r12\n";
	O << "\tbctr\n";
	SwitchToDataSection(".lazy_symbol_pointer", 0);
	O << "L" << *i << "$lazy_ptr:\n";
	O << "\t.indirect_symbol " << *i << "\n";
	if (isPPC64)
	O << "\t.quad dyld_stub_binding_helper\n";
	else
	O << "\t.long dyld_stub_binding_helper\n";
	}
	}

	O << "\n";

	// Output stubs for external and common global variables.
	if (GVStubs.begin() != GVStubs.end()) {
	SwitchToDataSection(".non_lazy_symbol_pointer", 0);
	for (std::set<std::string>::iterator I = GVStubs.begin(),
	E = GVStubs.end(); I != E; ++I) {
	O << "L" << *I << "$non_lazy_ptr:\n";
	O << "\t.indirect_symbol " << *I << "\n";
	if (isPPC64)
	O << "\t.quad\t0\n";
	else
	O << "\t.long\t0\n";

	}
	}

	// Emit initial debug information.
	DW.EndModule();

	// Funny Darwin hack: This flag tells the linker that no global symbols
	// contain code that falls through to other global symbols (e.g. the obvious
	// implementation of multiple entry points). If this doesn't occur, the
	// linker can safely perform dead code stripping. Since LLVM never generates
	// code that does this, it is always safe to set.
	O << "\t.subsections_via_symbols\n";

	AsmPrinter::doFinalization(M);
	return false; // success
	}



	/// createDarwinCodePrinterPass - Returns a pass that prints the PPC assembly
	/// code for a MachineFunction to the given output stream, in a format that the
	/// Darwin assembler can deal with.
	///
	FunctionPass *llvm::createPPCAsmPrinterPass(std::ostream &o,
	PPCTargetMachine &tm) {
	return new DarwinAsmPrinter(o, tm, tm.getTargetAsmInfo());
	}