ARMAsmPrinter.cpp revision fc3dc102e0bef8ecb7cd13ceab77dc130175f792
1//===-- ARMAsmPrinter.cpp - Print machine code to an ARM .s file ----------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file contains a printer that converts from our internal representation
11// of machine-dependent LLVM code to GAS-format ARM assembly language.
12//
13//===----------------------------------------------------------------------===//
14
15#define DEBUG_TYPE "asm-printer"
16#include "ARMAsmPrinter.h"
17#include "ARM.h"
18#include "ARMBuildAttrs.h"
19#include "ARMConstantPoolValue.h"
20#include "ARMMachineFunctionInfo.h"
21#include "ARMTargetMachine.h"
22#include "ARMTargetObjectFile.h"
23#include "InstPrinter/ARMInstPrinter.h"
24#include "MCTargetDesc/ARMAddressingModes.h"
25#include "MCTargetDesc/ARMMCExpr.h"
26#include "llvm/ADT/SetVector.h"
27#include "llvm/ADT/SmallString.h"
28#include "llvm/Assembly/Writer.h"
29#include "llvm/CodeGen/MachineFunctionPass.h"
30#include "llvm/CodeGen/MachineJumpTableInfo.h"
31#include "llvm/CodeGen/MachineModuleInfoImpls.h"
32#include "llvm/DebugInfo.h"
33#include "llvm/IR/Constants.h"
34#include "llvm/IR/DataLayout.h"
35#include "llvm/IR/Module.h"
36#include "llvm/IR/Type.h"
37#include "llvm/MC/MCAsmInfo.h"
38#include "llvm/MC/MCAssembler.h"
39#include "llvm/MC/MCContext.h"
40#include "llvm/MC/MCELFStreamer.h"
41#include "llvm/MC/MCInst.h"
42#include "llvm/MC/MCInstBuilder.h"
43#include "llvm/MC/MCObjectStreamer.h"
44#include "llvm/MC/MCSectionMachO.h"
45#include "llvm/MC/MCStreamer.h"
46#include "llvm/MC/MCSymbol.h"
47#include "llvm/Support/CommandLine.h"
48#include "llvm/Support/Debug.h"
49#include "llvm/Support/ELF.h"
50#include "llvm/Support/ErrorHandling.h"
51#include "llvm/Support/TargetRegistry.h"
52#include "llvm/Support/raw_ostream.h"
53#include "llvm/Target/Mangler.h"
54#include "llvm/Target/TargetMachine.h"
55#include <cctype>
56using namespace llvm;
57
58namespace {
59
60  // Per section and per symbol attributes are not supported.
61  // To implement them we would need the ability to delay this emission
62  // until the assembly file is fully parsed/generated as only then do we
63  // know the symbol and section numbers.
64  class AttributeEmitter {
65  public:
66    virtual void MaybeSwitchVendor(StringRef Vendor) = 0;
67    virtual void EmitAttribute(unsigned Attribute, unsigned Value) = 0;
68    virtual void EmitTextAttribute(unsigned Attribute, StringRef String) = 0;
69    virtual void Finish() = 0;
70    virtual ~AttributeEmitter() {}
71  };
72
73  class AsmAttributeEmitter : public AttributeEmitter {
74    MCStreamer &Streamer;
75
76  public:
77    AsmAttributeEmitter(MCStreamer &Streamer_) : Streamer(Streamer_) {}
78    void MaybeSwitchVendor(StringRef Vendor) { }
79
80    void EmitAttribute(unsigned Attribute, unsigned Value) {
81      Streamer.EmitRawText("\t.eabi_attribute " +
82                           Twine(Attribute) + ", " + Twine(Value));
83    }
84
85    void EmitTextAttribute(unsigned Attribute, StringRef String) {
86      switch (Attribute) {
87      default: llvm_unreachable("Unsupported Text attribute in ASM Mode");
88      case ARMBuildAttrs::CPU_name:
89        Streamer.EmitRawText(StringRef("\t.cpu ") + String.lower());
90        break;
91      /* GAS requires .fpu to be emitted regardless of EABI attribute */
92      case ARMBuildAttrs::Advanced_SIMD_arch:
93      case ARMBuildAttrs::VFP_arch:
94        Streamer.EmitRawText(StringRef("\t.fpu ") + String.lower());
95        break;
96      }
97    }
98    void Finish() { }
99  };
100
101  class ObjectAttributeEmitter : public AttributeEmitter {
102    // This structure holds all attributes, accounting for
103    // their string/numeric value, so we can later emmit them
104    // in declaration order, keeping all in the same vector
105    struct AttributeItemType {
106      enum {
107        HiddenAttribute = 0,
108        NumericAttribute,
109        TextAttribute
110      } Type;
111      unsigned Tag;
112      unsigned IntValue;
113      StringRef StringValue;
114    };
115
116    MCObjectStreamer &Streamer;
117    StringRef CurrentVendor;
118    SmallVector<AttributeItemType, 64> Contents;
119
120    // Account for the ULEB/String size of each item,
121    // not just the number of items
122    size_t ContentsSize;
123    // FIXME: this should be in a more generic place, but
124    // getULEBSize() is in MCAsmInfo and will be moved to MCDwarf
125    size_t getULEBSize(int Value) {
126      size_t Size = 0;
127      do {
128        Value >>= 7;
129        Size += sizeof(int8_t); // Is this really necessary?
130      } while (Value);
131      return Size;
132    }
133
134  public:
135    ObjectAttributeEmitter(MCObjectStreamer &Streamer_) :
136      Streamer(Streamer_), CurrentVendor(""), ContentsSize(0) { }
137
138    void MaybeSwitchVendor(StringRef Vendor) {
139      assert(!Vendor.empty() && "Vendor cannot be empty.");
140
141      if (CurrentVendor.empty())
142        CurrentVendor = Vendor;
143      else if (CurrentVendor == Vendor)
144        return;
145      else
146        Finish();
147
148      CurrentVendor = Vendor;
149
150      assert(Contents.size() == 0);
151    }
152
153    void EmitAttribute(unsigned Attribute, unsigned Value) {
154      AttributeItemType attr = {
155        AttributeItemType::NumericAttribute,
156        Attribute,
157        Value,
158        StringRef("")
159      };
160      ContentsSize += getULEBSize(Attribute);
161      ContentsSize += getULEBSize(Value);
162      Contents.push_back(attr);
163    }
164
165    void EmitTextAttribute(unsigned Attribute, StringRef String) {
166      AttributeItemType attr = {
167        AttributeItemType::TextAttribute,
168        Attribute,
169        0,
170        String
171      };
172      ContentsSize += getULEBSize(Attribute);
173      // String + \0
174      ContentsSize += String.size()+1;
175
176      Contents.push_back(attr);
177    }
178
179    void Finish() {
180      // Vendor size + Vendor name + '\0'
181      const size_t VendorHeaderSize = 4 + CurrentVendor.size() + 1;
182
183      // Tag + Tag Size
184      const size_t TagHeaderSize = 1 + 4;
185
186      Streamer.EmitIntValue(VendorHeaderSize + TagHeaderSize + ContentsSize, 4);
187      Streamer.EmitBytes(CurrentVendor);
188      Streamer.EmitIntValue(0, 1); // '\0'
189
190      Streamer.EmitIntValue(ARMBuildAttrs::File, 1);
191      Streamer.EmitIntValue(TagHeaderSize + ContentsSize, 4);
192
193      // Size should have been accounted for already, now
194      // emit each field as its type (ULEB or String)
195      for (unsigned int i=0; i<Contents.size(); ++i) {
196        AttributeItemType item = Contents[i];
197        Streamer.EmitULEB128IntValue(item.Tag);
198        switch (item.Type) {
199        default: llvm_unreachable("Invalid attribute type");
200        case AttributeItemType::NumericAttribute:
201          Streamer.EmitULEB128IntValue(item.IntValue);
202          break;
203        case AttributeItemType::TextAttribute:
204          Streamer.EmitBytes(item.StringValue.upper());
205          Streamer.EmitIntValue(0, 1); // '\0'
206          break;
207        }
208      }
209
210      Contents.clear();
211    }
212  };
213
214} // end of anonymous namespace
215
216/// EmitDwarfRegOp - Emit dwarf register operation.
217void ARMAsmPrinter::EmitDwarfRegOp(const MachineLocation &MLoc,
218                                   bool Indirect) const {
219  const TargetRegisterInfo *RI = TM.getRegisterInfo();
220  if (RI->getDwarfRegNum(MLoc.getReg(), false) != -1) {
221    AsmPrinter::EmitDwarfRegOp(MLoc, Indirect);
222    return;
223  }
224  assert(MLoc.isReg() && !Indirect &&
225         "This doesn't support offset/indirection - implement it if needed");
226  unsigned Reg = MLoc.getReg();
227  if (Reg >= ARM::S0 && Reg <= ARM::S31) {
228    assert(ARM::S0 + 31 == ARM::S31 && "Unexpected ARM S register numbering");
229    // S registers are described as bit-pieces of a register
230    // S[2x] = DW_OP_regx(256 + (x>>1)) DW_OP_bit_piece(32, 0)
231    // S[2x+1] = DW_OP_regx(256 + (x>>1)) DW_OP_bit_piece(32, 32)
232
233    unsigned SReg = Reg - ARM::S0;
234    bool odd = SReg & 0x1;
235    unsigned Rx = 256 + (SReg >> 1);
236
237    OutStreamer.AddComment("DW_OP_regx for S register");
238    EmitInt8(dwarf::DW_OP_regx);
239
240    OutStreamer.AddComment(Twine(SReg));
241    EmitULEB128(Rx);
242
243    if (odd) {
244      OutStreamer.AddComment("DW_OP_bit_piece 32 32");
245      EmitInt8(dwarf::DW_OP_bit_piece);
246      EmitULEB128(32);
247      EmitULEB128(32);
248    } else {
249      OutStreamer.AddComment("DW_OP_bit_piece 32 0");
250      EmitInt8(dwarf::DW_OP_bit_piece);
251      EmitULEB128(32);
252      EmitULEB128(0);
253    }
254  } else if (Reg >= ARM::Q0 && Reg <= ARM::Q15) {
255    assert(ARM::Q0 + 15 == ARM::Q15 && "Unexpected ARM Q register numbering");
256    // Q registers Q0-Q15 are described by composing two D registers together.
257    // Qx = DW_OP_regx(256+2x) DW_OP_piece(8) DW_OP_regx(256+2x+1)
258    // DW_OP_piece(8)
259
260    unsigned QReg = Reg - ARM::Q0;
261    unsigned D1 = 256 + 2 * QReg;
262    unsigned D2 = D1 + 1;
263
264    OutStreamer.AddComment("DW_OP_regx for Q register: D1");
265    EmitInt8(dwarf::DW_OP_regx);
266    EmitULEB128(D1);
267    OutStreamer.AddComment("DW_OP_piece 8");
268    EmitInt8(dwarf::DW_OP_piece);
269    EmitULEB128(8);
270
271    OutStreamer.AddComment("DW_OP_regx for Q register: D2");
272    EmitInt8(dwarf::DW_OP_regx);
273    EmitULEB128(D2);
274    OutStreamer.AddComment("DW_OP_piece 8");
275    EmitInt8(dwarf::DW_OP_piece);
276    EmitULEB128(8);
277  }
278}
279
280void ARMAsmPrinter::EmitFunctionBodyEnd() {
281  // Make sure to terminate any constant pools that were at the end
282  // of the function.
283  if (!InConstantPool)
284    return;
285  InConstantPool = false;
286  OutStreamer.EmitDataRegion(MCDR_DataRegionEnd);
287}
288
289void ARMAsmPrinter::EmitFunctionEntryLabel() {
290  if (AFI->isThumbFunction()) {
291    OutStreamer.EmitAssemblerFlag(MCAF_Code16);
292    OutStreamer.EmitThumbFunc(CurrentFnSym);
293  }
294
295  OutStreamer.EmitLabel(CurrentFnSym);
296}
297
298void ARMAsmPrinter::EmitXXStructor(const Constant *CV) {
299  uint64_t Size = TM.getDataLayout()->getTypeAllocSize(CV->getType());
300  assert(Size && "C++ constructor pointer had zero size!");
301
302  const GlobalValue *GV = dyn_cast<GlobalValue>(CV->stripPointerCasts());
303  assert(GV && "C++ constructor pointer was not a GlobalValue!");
304
305  const MCExpr *E = MCSymbolRefExpr::Create(Mang->getSymbol(GV),
306                                            (Subtarget->isTargetDarwin()
307                                             ? MCSymbolRefExpr::VK_None
308                                             : MCSymbolRefExpr::VK_ARM_TARGET1),
309                                            OutContext);
310
311  OutStreamer.EmitValue(E, Size);
312}
313
314/// runOnMachineFunction - This uses the EmitInstruction()
315/// method to print assembly for each instruction.
316///
317bool ARMAsmPrinter::runOnMachineFunction(MachineFunction &MF) {
318  AFI = MF.getInfo<ARMFunctionInfo>();
319  MCP = MF.getConstantPool();
320
321  return AsmPrinter::runOnMachineFunction(MF);
322}
323
324void ARMAsmPrinter::printOperand(const MachineInstr *MI, int OpNum,
325                                 raw_ostream &O, const char *Modifier) {
326  const MachineOperand &MO = MI->getOperand(OpNum);
327  unsigned TF = MO.getTargetFlags();
328
329  switch (MO.getType()) {
330  default: llvm_unreachable("<unknown operand type>");
331  case MachineOperand::MO_Register: {
332    unsigned Reg = MO.getReg();
333    assert(TargetRegisterInfo::isPhysicalRegister(Reg));
334    assert(!MO.getSubReg() && "Subregs should be eliminated!");
335    if(ARM::GPRPairRegClass.contains(Reg)) {
336      const MachineFunction &MF = *MI->getParent()->getParent();
337      const TargetRegisterInfo *TRI = MF.getTarget().getRegisterInfo();
338      Reg = TRI->getSubReg(Reg, ARM::gsub_0);
339    }
340    O << ARMInstPrinter::getRegisterName(Reg);
341    break;
342  }
343  case MachineOperand::MO_Immediate: {
344    int64_t Imm = MO.getImm();
345    O << '#';
346    if ((Modifier && strcmp(Modifier, "lo16") == 0) ||
347        (TF == ARMII::MO_LO16))
348      O << ":lower16:";
349    else if ((Modifier && strcmp(Modifier, "hi16") == 0) ||
350             (TF == ARMII::MO_HI16))
351      O << ":upper16:";
352    O << Imm;
353    break;
354  }
355  case MachineOperand::MO_MachineBasicBlock:
356    O << *MO.getMBB()->getSymbol();
357    return;
358  case MachineOperand::MO_GlobalAddress: {
359    const GlobalValue *GV = MO.getGlobal();
360    if ((Modifier && strcmp(Modifier, "lo16") == 0) ||
361        (TF & ARMII::MO_LO16))
362      O << ":lower16:";
363    else if ((Modifier && strcmp(Modifier, "hi16") == 0) ||
364             (TF & ARMII::MO_HI16))
365      O << ":upper16:";
366    O << *Mang->getSymbol(GV);
367
368    printOffset(MO.getOffset(), O);
369    if (TF == ARMII::MO_PLT)
370      O << "(PLT)";
371    break;
372  }
373  case MachineOperand::MO_ExternalSymbol: {
374    O << *GetExternalSymbolSymbol(MO.getSymbolName());
375    if (TF == ARMII::MO_PLT)
376      O << "(PLT)";
377    break;
378  }
379  case MachineOperand::MO_ConstantPoolIndex:
380    O << *GetCPISymbol(MO.getIndex());
381    break;
382  case MachineOperand::MO_JumpTableIndex:
383    O << *GetJTISymbol(MO.getIndex());
384    break;
385  }
386}
387
388//===--------------------------------------------------------------------===//
389
390MCSymbol *ARMAsmPrinter::
391GetARMJTIPICJumpTableLabel2(unsigned uid, unsigned uid2) const {
392  SmallString<60> Name;
393  raw_svector_ostream(Name) << MAI->getPrivateGlobalPrefix() << "JTI"
394    << getFunctionNumber() << '_' << uid << '_' << uid2;
395  return OutContext.GetOrCreateSymbol(Name.str());
396}
397
398
399MCSymbol *ARMAsmPrinter::GetARMSJLJEHLabel() const {
400  SmallString<60> Name;
401  raw_svector_ostream(Name) << MAI->getPrivateGlobalPrefix() << "SJLJEH"
402    << getFunctionNumber();
403  return OutContext.GetOrCreateSymbol(Name.str());
404}
405
406bool ARMAsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNum,
407                                    unsigned AsmVariant, const char *ExtraCode,
408                                    raw_ostream &O) {
409  // Does this asm operand have a single letter operand modifier?
410  if (ExtraCode && ExtraCode[0]) {
411    if (ExtraCode[1] != 0) return true; // Unknown modifier.
412
413    switch (ExtraCode[0]) {
414    default:
415      // See if this is a generic print operand
416      return AsmPrinter::PrintAsmOperand(MI, OpNum, AsmVariant, ExtraCode, O);
417    case 'a': // Print as a memory address.
418      if (MI->getOperand(OpNum).isReg()) {
419        O << "["
420          << ARMInstPrinter::getRegisterName(MI->getOperand(OpNum).getReg())
421          << "]";
422        return false;
423      }
424      // Fallthrough
425    case 'c': // Don't print "#" before an immediate operand.
426      if (!MI->getOperand(OpNum).isImm())
427        return true;
428      O << MI->getOperand(OpNum).getImm();
429      return false;
430    case 'P': // Print a VFP double precision register.
431    case 'q': // Print a NEON quad precision register.
432      printOperand(MI, OpNum, O);
433      return false;
434    case 'y': // Print a VFP single precision register as indexed double.
435      if (MI->getOperand(OpNum).isReg()) {
436        unsigned Reg = MI->getOperand(OpNum).getReg();
437        const TargetRegisterInfo *TRI = MF->getTarget().getRegisterInfo();
438        // Find the 'd' register that has this 's' register as a sub-register,
439        // and determine the lane number.
440        for (MCSuperRegIterator SR(Reg, TRI); SR.isValid(); ++SR) {
441          if (!ARM::DPRRegClass.contains(*SR))
442            continue;
443          bool Lane0 = TRI->getSubReg(*SR, ARM::ssub_0) == Reg;
444          O << ARMInstPrinter::getRegisterName(*SR) << (Lane0 ? "[0]" : "[1]");
445          return false;
446        }
447      }
448      return true;
449    case 'B': // Bitwise inverse of integer or symbol without a preceding #.
450      if (!MI->getOperand(OpNum).isImm())
451        return true;
452      O << ~(MI->getOperand(OpNum).getImm());
453      return false;
454    case 'L': // The low 16 bits of an immediate constant.
455      if (!MI->getOperand(OpNum).isImm())
456        return true;
457      O << (MI->getOperand(OpNum).getImm() & 0xffff);
458      return false;
459    case 'M': { // A register range suitable for LDM/STM.
460      if (!MI->getOperand(OpNum).isReg())
461        return true;
462      const MachineOperand &MO = MI->getOperand(OpNum);
463      unsigned RegBegin = MO.getReg();
464      // This takes advantage of the 2 operand-ness of ldm/stm and that we've
465      // already got the operands in registers that are operands to the
466      // inline asm statement.
467      O << "{";
468      if (ARM::GPRPairRegClass.contains(RegBegin)) {
469        const TargetRegisterInfo *TRI = MF->getTarget().getRegisterInfo();
470        unsigned Reg0 = TRI->getSubReg(RegBegin, ARM::gsub_0);
471        O << ARMInstPrinter::getRegisterName(Reg0) << ", ";;
472        RegBegin = TRI->getSubReg(RegBegin, ARM::gsub_1);
473      }
474      O << ARMInstPrinter::getRegisterName(RegBegin);
475
476      // FIXME: The register allocator not only may not have given us the
477      // registers in sequence, but may not be in ascending registers. This
478      // will require changes in the register allocator that'll need to be
479      // propagated down here if the operands change.
480      unsigned RegOps = OpNum + 1;
481      while (MI->getOperand(RegOps).isReg()) {
482        O << ", "
483          << ARMInstPrinter::getRegisterName(MI->getOperand(RegOps).getReg());
484        RegOps++;
485      }
486
487      O << "}";
488
489      return false;
490    }
491    case 'R': // The most significant register of a pair.
492    case 'Q': { // The least significant register of a pair.
493      if (OpNum == 0)
494        return true;
495      const MachineOperand &FlagsOP = MI->getOperand(OpNum - 1);
496      if (!FlagsOP.isImm())
497        return true;
498      unsigned Flags = FlagsOP.getImm();
499
500      // This operand may not be the one that actually provides the register. If
501      // it's tied to a previous one then we should refer instead to that one
502      // for registers and their classes.
503      unsigned TiedIdx;
504      if (InlineAsm::isUseOperandTiedToDef(Flags, TiedIdx)) {
505        for (OpNum = InlineAsm::MIOp_FirstOperand; TiedIdx; --TiedIdx) {
506          unsigned OpFlags = MI->getOperand(OpNum).getImm();
507          OpNum += InlineAsm::getNumOperandRegisters(OpFlags) + 1;
508        }
509        Flags = MI->getOperand(OpNum).getImm();
510
511        // Later code expects OpNum to be pointing at the register rather than
512        // the flags.
513        OpNum += 1;
514      }
515
516      unsigned NumVals = InlineAsm::getNumOperandRegisters(Flags);
517      unsigned RC;
518      InlineAsm::hasRegClassConstraint(Flags, RC);
519      if (RC == ARM::GPRPairRegClassID) {
520        if (NumVals != 1)
521          return true;
522        const MachineOperand &MO = MI->getOperand(OpNum);
523        if (!MO.isReg())
524          return true;
525        const TargetRegisterInfo *TRI = MF->getTarget().getRegisterInfo();
526        unsigned Reg = TRI->getSubReg(MO.getReg(), ExtraCode[0] == 'Q' ?
527            ARM::gsub_0 : ARM::gsub_1);
528        O << ARMInstPrinter::getRegisterName(Reg);
529        return false;
530      }
531      if (NumVals != 2)
532        return true;
533      unsigned RegOp = ExtraCode[0] == 'Q' ? OpNum : OpNum + 1;
534      if (RegOp >= MI->getNumOperands())
535        return true;
536      const MachineOperand &MO = MI->getOperand(RegOp);
537      if (!MO.isReg())
538        return true;
539      unsigned Reg = MO.getReg();
540      O << ARMInstPrinter::getRegisterName(Reg);
541      return false;
542    }
543
544    case 'e': // The low doubleword register of a NEON quad register.
545    case 'f': { // The high doubleword register of a NEON quad register.
546      if (!MI->getOperand(OpNum).isReg())
547        return true;
548      unsigned Reg = MI->getOperand(OpNum).getReg();
549      if (!ARM::QPRRegClass.contains(Reg))
550        return true;
551      const TargetRegisterInfo *TRI = MF->getTarget().getRegisterInfo();
552      unsigned SubReg = TRI->getSubReg(Reg, ExtraCode[0] == 'e' ?
553                                       ARM::dsub_0 : ARM::dsub_1);
554      O << ARMInstPrinter::getRegisterName(SubReg);
555      return false;
556    }
557
558    // This modifier is not yet supported.
559    case 'h': // A range of VFP/NEON registers suitable for VLD1/VST1.
560      return true;
561    case 'H': { // The highest-numbered register of a pair.
562      const MachineOperand &MO = MI->getOperand(OpNum);
563      if (!MO.isReg())
564        return true;
565      const MachineFunction &MF = *MI->getParent()->getParent();
566      const TargetRegisterInfo *TRI = MF.getTarget().getRegisterInfo();
567      unsigned Reg = MO.getReg();
568      if(!ARM::GPRPairRegClass.contains(Reg))
569        return false;
570      Reg = TRI->getSubReg(Reg, ARM::gsub_1);
571      O << ARMInstPrinter::getRegisterName(Reg);
572      return false;
573    }
574    }
575  }
576
577  printOperand(MI, OpNum, O);
578  return false;
579}
580
581bool ARMAsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI,
582                                          unsigned OpNum, unsigned AsmVariant,
583                                          const char *ExtraCode,
584                                          raw_ostream &O) {
585  // Does this asm operand have a single letter operand modifier?
586  if (ExtraCode && ExtraCode[0]) {
587    if (ExtraCode[1] != 0) return true; // Unknown modifier.
588
589    switch (ExtraCode[0]) {
590      case 'A': // A memory operand for a VLD1/VST1 instruction.
591      default: return true;  // Unknown modifier.
592      case 'm': // The base register of a memory operand.
593        if (!MI->getOperand(OpNum).isReg())
594          return true;
595        O << ARMInstPrinter::getRegisterName(MI->getOperand(OpNum).getReg());
596        return false;
597    }
598  }
599
600  const MachineOperand &MO = MI->getOperand(OpNum);
601  assert(MO.isReg() && "unexpected inline asm memory operand");
602  O << "[" << ARMInstPrinter::getRegisterName(MO.getReg()) << "]";
603  return false;
604}
605
606void ARMAsmPrinter::EmitStartOfAsmFile(Module &M) {
607  if (Subtarget->isTargetDarwin()) {
608    Reloc::Model RelocM = TM.getRelocationModel();
609    if (RelocM == Reloc::PIC_ || RelocM == Reloc::DynamicNoPIC) {
610      // Declare all the text sections up front (before the DWARF sections
611      // emitted by AsmPrinter::doInitialization) so the assembler will keep
612      // them together at the beginning of the object file.  This helps
613      // avoid out-of-range branches that are due a fundamental limitation of
614      // the way symbol offsets are encoded with the current Darwin ARM
615      // relocations.
616      const TargetLoweringObjectFileMachO &TLOFMacho =
617        static_cast<const TargetLoweringObjectFileMachO &>(
618          getObjFileLowering());
619
620      // Collect the set of sections our functions will go into.
621      SetVector<const MCSection *, SmallVector<const MCSection *, 8>,
622        SmallPtrSet<const MCSection *, 8> > TextSections;
623      // Default text section comes first.
624      TextSections.insert(TLOFMacho.getTextSection());
625      // Now any user defined text sections from function attributes.
626      for (Module::iterator F = M.begin(), e = M.end(); F != e; ++F)
627        if (!F->isDeclaration() && !F->hasAvailableExternallyLinkage())
628          TextSections.insert(TLOFMacho.SectionForGlobal(F, Mang, TM));
629      // Now the coalescable sections.
630      TextSections.insert(TLOFMacho.getTextCoalSection());
631      TextSections.insert(TLOFMacho.getConstTextCoalSection());
632
633      // Emit the sections in the .s file header to fix the order.
634      for (unsigned i = 0, e = TextSections.size(); i != e; ++i)
635        OutStreamer.SwitchSection(TextSections[i]);
636
637      if (RelocM == Reloc::DynamicNoPIC) {
638        const MCSection *sect =
639          OutContext.getMachOSection("__TEXT", "__symbol_stub4",
640                                     MCSectionMachO::S_SYMBOL_STUBS,
641                                     12, SectionKind::getText());
642        OutStreamer.SwitchSection(sect);
643      } else {
644        const MCSection *sect =
645          OutContext.getMachOSection("__TEXT", "__picsymbolstub4",
646                                     MCSectionMachO::S_SYMBOL_STUBS,
647                                     16, SectionKind::getText());
648        OutStreamer.SwitchSection(sect);
649      }
650      const MCSection *StaticInitSect =
651        OutContext.getMachOSection("__TEXT", "__StaticInit",
652                                   MCSectionMachO::S_REGULAR |
653                                   MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS,
654                                   SectionKind::getText());
655      OutStreamer.SwitchSection(StaticInitSect);
656    }
657  }
658
659  // Use unified assembler syntax.
660  OutStreamer.EmitAssemblerFlag(MCAF_SyntaxUnified);
661
662  // Emit ARM Build Attributes
663  if (Subtarget->isTargetELF())
664    emitAttributes();
665}
666
667
668void ARMAsmPrinter::EmitEndOfAsmFile(Module &M) {
669  if (Subtarget->isTargetDarwin()) {
670    // All darwin targets use mach-o.
671    const TargetLoweringObjectFileMachO &TLOFMacho =
672      static_cast<const TargetLoweringObjectFileMachO &>(getObjFileLowering());
673    MachineModuleInfoMachO &MMIMacho =
674      MMI->getObjFileInfo<MachineModuleInfoMachO>();
675
676    // Output non-lazy-pointers for external and common global variables.
677    MachineModuleInfoMachO::SymbolListTy Stubs = MMIMacho.GetGVStubList();
678
679    if (!Stubs.empty()) {
680      // Switch with ".non_lazy_symbol_pointer" directive.
681      OutStreamer.SwitchSection(TLOFMacho.getNonLazySymbolPointerSection());
682      EmitAlignment(2);
683      for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
684        // L_foo$stub:
685        OutStreamer.EmitLabel(Stubs[i].first);
686        //   .indirect_symbol _foo
687        MachineModuleInfoImpl::StubValueTy &MCSym = Stubs[i].second;
688        OutStreamer.EmitSymbolAttribute(MCSym.getPointer(),MCSA_IndirectSymbol);
689
690        if (MCSym.getInt())
691          // External to current translation unit.
692          OutStreamer.EmitIntValue(0, 4/*size*/);
693        else
694          // Internal to current translation unit.
695          //
696          // When we place the LSDA into the TEXT section, the type info
697          // pointers need to be indirect and pc-rel. We accomplish this by
698          // using NLPs; however, sometimes the types are local to the file.
699          // We need to fill in the value for the NLP in those cases.
700          OutStreamer.EmitValue(MCSymbolRefExpr::Create(MCSym.getPointer(),
701                                                        OutContext),
702                                4/*size*/);
703      }
704
705      Stubs.clear();
706      OutStreamer.AddBlankLine();
707    }
708
709    Stubs = MMIMacho.GetHiddenGVStubList();
710    if (!Stubs.empty()) {
711      OutStreamer.SwitchSection(getObjFileLowering().getDataSection());
712      EmitAlignment(2);
713      for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
714        // L_foo$stub:
715        OutStreamer.EmitLabel(Stubs[i].first);
716        //   .long _foo
717        OutStreamer.EmitValue(MCSymbolRefExpr::
718                              Create(Stubs[i].second.getPointer(),
719                                     OutContext),
720                              4/*size*/);
721      }
722
723      Stubs.clear();
724      OutStreamer.AddBlankLine();
725    }
726
727    // Funny Darwin hack: This flag tells the linker that no global symbols
728    // contain code that falls through to other global symbols (e.g. the obvious
729    // implementation of multiple entry points).  If this doesn't occur, the
730    // linker can safely perform dead code stripping.  Since LLVM never
731    // generates code that does this, it is always safe to set.
732    OutStreamer.EmitAssemblerFlag(MCAF_SubsectionsViaSymbols);
733  }
734}
735
736//===----------------------------------------------------------------------===//
737// Helper routines for EmitStartOfAsmFile() and EmitEndOfAsmFile()
738// FIXME:
739// The following seem like one-off assembler flags, but they actually need
740// to appear in the .ARM.attributes section in ELF.
741// Instead of subclassing the MCELFStreamer, we do the work here.
742
743static ARMBuildAttrs::CPUArch getArchForCPU(StringRef CPU,
744                                            const ARMSubtarget *Subtarget) {
745  if (CPU == "xscale")
746    return ARMBuildAttrs::v5TEJ;
747
748  if (Subtarget->hasV8Ops())
749    return ARMBuildAttrs::v8;
750  else if (Subtarget->hasV7Ops()) {
751    if (Subtarget->isMClass() && Subtarget->hasThumb2DSP())
752      return ARMBuildAttrs::v7E_M;
753    return ARMBuildAttrs::v7;
754  } else if (Subtarget->hasV6T2Ops())
755    return ARMBuildAttrs::v6T2;
756  else if (Subtarget->hasV6MOps())
757    return ARMBuildAttrs::v6S_M;
758  else if (Subtarget->hasV6Ops())
759    return ARMBuildAttrs::v6;
760  else if (Subtarget->hasV5TEOps())
761    return ARMBuildAttrs::v5TE;
762  else if (Subtarget->hasV5TOps())
763    return ARMBuildAttrs::v5T;
764  else if (Subtarget->hasV4TOps())
765    return ARMBuildAttrs::v4T;
766  else
767    return ARMBuildAttrs::v4;
768}
769
770void ARMAsmPrinter::emitAttributes() {
771
772  emitARMAttributeSection();
773
774  /* GAS expect .fpu to be emitted, regardless of VFP build attribute */
775  bool emitFPU = false;
776  AttributeEmitter *AttrEmitter;
777  if (OutStreamer.hasRawTextSupport()) {
778    AttrEmitter = new AsmAttributeEmitter(OutStreamer);
779    emitFPU = true;
780  } else {
781    MCObjectStreamer &O = static_cast<MCObjectStreamer&>(OutStreamer);
782    AttrEmitter = new ObjectAttributeEmitter(O);
783  }
784
785  AttrEmitter->MaybeSwitchVendor("aeabi");
786
787  std::string CPUString = Subtarget->getCPUString();
788
789  if (CPUString != "generic")
790    AttrEmitter->EmitTextAttribute(ARMBuildAttrs::CPU_name, CPUString);
791
792  AttrEmitter->EmitAttribute(ARMBuildAttrs::CPU_arch,
793                             getArchForCPU(CPUString, Subtarget));
794
795  if (Subtarget->isAClass()) {
796    AttrEmitter->EmitAttribute(ARMBuildAttrs::CPU_arch_profile,
797                               ARMBuildAttrs::ApplicationProfile);
798  } else if (Subtarget->isRClass()) {
799    AttrEmitter->EmitAttribute(ARMBuildAttrs::CPU_arch_profile,
800                               ARMBuildAttrs::RealTimeProfile);
801  } else if (Subtarget->isMClass()){
802    AttrEmitter->EmitAttribute(ARMBuildAttrs::CPU_arch_profile,
803                               ARMBuildAttrs::MicroControllerProfile);
804  }
805
806  AttrEmitter->EmitAttribute(ARMBuildAttrs::ARM_ISA_use, Subtarget->hasARMOps() ?
807                           ARMBuildAttrs::Allowed : ARMBuildAttrs::Not_Allowed);
808  if (Subtarget->isThumb1Only()) {
809    AttrEmitter->EmitAttribute(ARMBuildAttrs::THUMB_ISA_use,
810                               ARMBuildAttrs::Allowed);
811  } else if (Subtarget->hasThumb2()) {
812    AttrEmitter->EmitAttribute(ARMBuildAttrs::THUMB_ISA_use,
813                               ARMBuildAttrs::AllowThumb32);
814  }
815
816  if (Subtarget->hasNEON() && emitFPU) {
817    /* NEON is not exactly a VFP architecture, but GAS emit one of
818     * neon/neon-fp-armv8/neon-vfpv4/vfpv3/vfpv2 for .fpu parameters */
819    if (Subtarget->hasFPARMv8()) {
820      if (Subtarget->hasCrypto())
821        AttrEmitter->EmitTextAttribute(ARMBuildAttrs::Advanced_SIMD_arch,
822                                       "crypto-neon-fp-armv8");
823      else
824        AttrEmitter->EmitTextAttribute(ARMBuildAttrs::Advanced_SIMD_arch,
825                                       "neon-fp-armv8");
826    }
827    else if (Subtarget->hasVFP4())
828      AttrEmitter->EmitTextAttribute(ARMBuildAttrs::Advanced_SIMD_arch,
829                                     "neon-vfpv4");
830    else
831      AttrEmitter->EmitTextAttribute(ARMBuildAttrs::Advanced_SIMD_arch, "neon");
832    /* If emitted for NEON, omit from VFP below, since you can have both
833     * NEON and VFP in build attributes but only one .fpu */
834    emitFPU = false;
835  }
836
837  /* FPARMv8 + .fpu */
838  if (Subtarget->hasFPARMv8()) {
839    AttrEmitter->EmitAttribute(ARMBuildAttrs::VFP_arch,
840                               ARMBuildAttrs::AllowFPARMv8A);
841    if (emitFPU)
842      AttrEmitter->EmitTextAttribute(ARMBuildAttrs::VFP_arch, "fp-armv8");
843    /* VFPv4 + .fpu */
844  } else if (Subtarget->hasVFP4()) {
845    AttrEmitter->EmitAttribute(ARMBuildAttrs::VFP_arch,
846      Subtarget->isFPOnlySP() ? ARMBuildAttrs::AllowFPv4B :
847                                ARMBuildAttrs::AllowFPv4A);
848    if (emitFPU)
849      AttrEmitter->EmitTextAttribute(ARMBuildAttrs::VFP_arch, "vfpv4");
850
851  /* VFPv3 + .fpu */
852  } else if (Subtarget->hasVFP3()) {
853    AttrEmitter->EmitAttribute(ARMBuildAttrs::VFP_arch,
854      Subtarget->isFPOnlySP() ? ARMBuildAttrs::AllowFPv3B :
855                                ARMBuildAttrs::AllowFPv3A);
856    if (emitFPU)
857      AttrEmitter->EmitTextAttribute(ARMBuildAttrs::VFP_arch, "vfpv3");
858
859  /* VFPv2 + .fpu */
860  } else if (Subtarget->hasVFP2()) {
861    AttrEmitter->EmitAttribute(ARMBuildAttrs::VFP_arch,
862                               ARMBuildAttrs::AllowFPv2);
863    if (emitFPU)
864      AttrEmitter->EmitTextAttribute(ARMBuildAttrs::VFP_arch, "vfpv2");
865  }
866
867  /* TODO: ARMBuildAttrs::Allowed is not completely accurate,
868   * since NEON can have 1 (allowed) or 2 (MAC operations) */
869  if (Subtarget->hasNEON()) {
870    if (Subtarget->hasV8Ops())
871      AttrEmitter->EmitAttribute(ARMBuildAttrs::Advanced_SIMD_arch,
872                                 ARMBuildAttrs::AllowedNeonV8);
873    else
874      AttrEmitter->EmitAttribute(ARMBuildAttrs::Advanced_SIMD_arch,
875                                 ARMBuildAttrs::Allowed);
876  }
877
878  // Signal various FP modes.
879  if (!TM.Options.UnsafeFPMath) {
880    AttrEmitter->EmitAttribute(ARMBuildAttrs::ABI_FP_denormal,
881                               ARMBuildAttrs::Allowed);
882    AttrEmitter->EmitAttribute(ARMBuildAttrs::ABI_FP_exceptions,
883                               ARMBuildAttrs::Allowed);
884  }
885
886  if (TM.Options.NoInfsFPMath && TM.Options.NoNaNsFPMath)
887    AttrEmitter->EmitAttribute(ARMBuildAttrs::ABI_FP_number_model,
888                               ARMBuildAttrs::Allowed);
889  else
890    AttrEmitter->EmitAttribute(ARMBuildAttrs::ABI_FP_number_model,
891                               ARMBuildAttrs::AllowIEE754);
892
893  // FIXME: add more flags to ARMBuildAttrs.h
894  // 8-bytes alignment stuff.
895  AttrEmitter->EmitAttribute(ARMBuildAttrs::ABI_align8_needed, 1);
896  AttrEmitter->EmitAttribute(ARMBuildAttrs::ABI_align8_preserved, 1);
897
898  // Hard float.  Use both S and D registers and conform to AAPCS-VFP.
899  if (Subtarget->isAAPCS_ABI() && TM.Options.FloatABIType == FloatABI::Hard) {
900    AttrEmitter->EmitAttribute(ARMBuildAttrs::ABI_HardFP_use, 3);
901    AttrEmitter->EmitAttribute(ARMBuildAttrs::ABI_VFP_args, 1);
902  }
903  // FIXME: Should we signal R9 usage?
904
905  if (Subtarget->hasDivide()) {
906    // Check if hardware divide is only available in thumb2 or ARM as well.
907    AttrEmitter->EmitAttribute(ARMBuildAttrs::DIV_use,
908      Subtarget->hasDivideInARMMode() ? ARMBuildAttrs::AllowDIVExt :
909                                        ARMBuildAttrs::AllowDIVIfExists);
910  }
911
912  AttrEmitter->Finish();
913  delete AttrEmitter;
914}
915
916void ARMAsmPrinter::emitARMAttributeSection() {
917  // <format-version>
918  // [ <section-length> "vendor-name"
919  // [ <file-tag> <size> <attribute>*
920  //   | <section-tag> <size> <section-number>* 0 <attribute>*
921  //   | <symbol-tag> <size> <symbol-number>* 0 <attribute>*
922  //   ]+
923  // ]*
924
925  if (OutStreamer.hasRawTextSupport())
926    return;
927
928  const ARMElfTargetObjectFile &TLOFELF =
929    static_cast<const ARMElfTargetObjectFile &>
930    (getObjFileLowering());
931
932  OutStreamer.SwitchSection(TLOFELF.getAttributesSection());
933
934  // Format version
935  OutStreamer.EmitIntValue(0x41, 1);
936}
937
938//===----------------------------------------------------------------------===//
939
940static MCSymbol *getPICLabel(const char *Prefix, unsigned FunctionNumber,
941                             unsigned LabelId, MCContext &Ctx) {
942
943  MCSymbol *Label = Ctx.GetOrCreateSymbol(Twine(Prefix)
944                       + "PC" + Twine(FunctionNumber) + "_" + Twine(LabelId));
945  return Label;
946}
947
948static MCSymbolRefExpr::VariantKind
949getModifierVariantKind(ARMCP::ARMCPModifier Modifier) {
950  switch (Modifier) {
951  case ARMCP::no_modifier: return MCSymbolRefExpr::VK_None;
952  case ARMCP::TLSGD:       return MCSymbolRefExpr::VK_ARM_TLSGD;
953  case ARMCP::TPOFF:       return MCSymbolRefExpr::VK_ARM_TPOFF;
954  case ARMCP::GOTTPOFF:    return MCSymbolRefExpr::VK_ARM_GOTTPOFF;
955  case ARMCP::GOT:         return MCSymbolRefExpr::VK_ARM_GOT;
956  case ARMCP::GOTOFF:      return MCSymbolRefExpr::VK_ARM_GOTOFF;
957  }
958  llvm_unreachable("Invalid ARMCPModifier!");
959}
960
961MCSymbol *ARMAsmPrinter::GetARMGVSymbol(const GlobalValue *GV) {
962  bool isIndirect = Subtarget->isTargetDarwin() &&
963    Subtarget->GVIsIndirectSymbol(GV, TM.getRelocationModel());
964  if (!isIndirect)
965    return Mang->getSymbol(GV);
966
967  // FIXME: Remove this when Darwin transition to @GOT like syntax.
968  MCSymbol *MCSym = GetSymbolWithGlobalValueBase(GV, "$non_lazy_ptr");
969  MachineModuleInfoMachO &MMIMachO =
970    MMI->getObjFileInfo<MachineModuleInfoMachO>();
971  MachineModuleInfoImpl::StubValueTy &StubSym =
972    GV->hasHiddenVisibility() ? MMIMachO.getHiddenGVStubEntry(MCSym) :
973    MMIMachO.getGVStubEntry(MCSym);
974  if (StubSym.getPointer() == 0)
975    StubSym = MachineModuleInfoImpl::
976      StubValueTy(Mang->getSymbol(GV), !GV->hasInternalLinkage());
977  return MCSym;
978}
979
980void ARMAsmPrinter::
981EmitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) {
982  int Size = TM.getDataLayout()->getTypeAllocSize(MCPV->getType());
983
984  ARMConstantPoolValue *ACPV = static_cast<ARMConstantPoolValue*>(MCPV);
985
986  MCSymbol *MCSym;
987  if (ACPV->isLSDA()) {
988    SmallString<128> Str;
989    raw_svector_ostream OS(Str);
990    OS << MAI->getPrivateGlobalPrefix() << "_LSDA_" << getFunctionNumber();
991    MCSym = OutContext.GetOrCreateSymbol(OS.str());
992  } else if (ACPV->isBlockAddress()) {
993    const BlockAddress *BA =
994      cast<ARMConstantPoolConstant>(ACPV)->getBlockAddress();
995    MCSym = GetBlockAddressSymbol(BA);
996  } else if (ACPV->isGlobalValue()) {
997    const GlobalValue *GV = cast<ARMConstantPoolConstant>(ACPV)->getGV();
998    MCSym = GetARMGVSymbol(GV);
999  } else if (ACPV->isMachineBasicBlock()) {
1000    const MachineBasicBlock *MBB = cast<ARMConstantPoolMBB>(ACPV)->getMBB();
1001    MCSym = MBB->getSymbol();
1002  } else {
1003    assert(ACPV->isExtSymbol() && "unrecognized constant pool value");
1004    const char *Sym = cast<ARMConstantPoolSymbol>(ACPV)->getSymbol();
1005    MCSym = GetExternalSymbolSymbol(Sym);
1006  }
1007
1008  // Create an MCSymbol for the reference.
1009  const MCExpr *Expr =
1010    MCSymbolRefExpr::Create(MCSym, getModifierVariantKind(ACPV->getModifier()),
1011                            OutContext);
1012
1013  if (ACPV->getPCAdjustment()) {
1014    MCSymbol *PCLabel = getPICLabel(MAI->getPrivateGlobalPrefix(),
1015                                    getFunctionNumber(),
1016                                    ACPV->getLabelId(),
1017                                    OutContext);
1018    const MCExpr *PCRelExpr = MCSymbolRefExpr::Create(PCLabel, OutContext);
1019    PCRelExpr =
1020      MCBinaryExpr::CreateAdd(PCRelExpr,
1021                              MCConstantExpr::Create(ACPV->getPCAdjustment(),
1022                                                     OutContext),
1023                              OutContext);
1024    if (ACPV->mustAddCurrentAddress()) {
1025      // We want "(<expr> - .)", but MC doesn't have a concept of the '.'
1026      // label, so just emit a local label end reference that instead.
1027      MCSymbol *DotSym = OutContext.CreateTempSymbol();
1028      OutStreamer.EmitLabel(DotSym);
1029      const MCExpr *DotExpr = MCSymbolRefExpr::Create(DotSym, OutContext);
1030      PCRelExpr = MCBinaryExpr::CreateSub(PCRelExpr, DotExpr, OutContext);
1031    }
1032    Expr = MCBinaryExpr::CreateSub(Expr, PCRelExpr, OutContext);
1033  }
1034  OutStreamer.EmitValue(Expr, Size);
1035}
1036
1037void ARMAsmPrinter::EmitJumpTable(const MachineInstr *MI) {
1038  unsigned Opcode = MI->getOpcode();
1039  int OpNum = 1;
1040  if (Opcode == ARM::BR_JTadd)
1041    OpNum = 2;
1042  else if (Opcode == ARM::BR_JTm)
1043    OpNum = 3;
1044
1045  const MachineOperand &MO1 = MI->getOperand(OpNum);
1046  const MachineOperand &MO2 = MI->getOperand(OpNum+1); // Unique Id
1047  unsigned JTI = MO1.getIndex();
1048
1049  // Emit a label for the jump table.
1050  MCSymbol *JTISymbol = GetARMJTIPICJumpTableLabel2(JTI, MO2.getImm());
1051  OutStreamer.EmitLabel(JTISymbol);
1052
1053  // Mark the jump table as data-in-code.
1054  OutStreamer.EmitDataRegion(MCDR_DataRegionJT32);
1055
1056  // Emit each entry of the table.
1057  const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo();
1058  const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
1059  const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs;
1060
1061  for (unsigned i = 0, e = JTBBs.size(); i != e; ++i) {
1062    MachineBasicBlock *MBB = JTBBs[i];
1063    // Construct an MCExpr for the entry. We want a value of the form:
1064    // (BasicBlockAddr - TableBeginAddr)
1065    //
1066    // For example, a table with entries jumping to basic blocks BB0 and BB1
1067    // would look like:
1068    // LJTI_0_0:
1069    //    .word (LBB0 - LJTI_0_0)
1070    //    .word (LBB1 - LJTI_0_0)
1071    const MCExpr *Expr = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
1072
1073    if (TM.getRelocationModel() == Reloc::PIC_)
1074      Expr = MCBinaryExpr::CreateSub(Expr, MCSymbolRefExpr::Create(JTISymbol,
1075                                                                   OutContext),
1076                                     OutContext);
1077    // If we're generating a table of Thumb addresses in static relocation
1078    // model, we need to add one to keep interworking correctly.
1079    else if (AFI->isThumbFunction())
1080      Expr = MCBinaryExpr::CreateAdd(Expr, MCConstantExpr::Create(1,OutContext),
1081                                     OutContext);
1082    OutStreamer.EmitValue(Expr, 4);
1083  }
1084  // Mark the end of jump table data-in-code region.
1085  OutStreamer.EmitDataRegion(MCDR_DataRegionEnd);
1086}
1087
1088void ARMAsmPrinter::EmitJump2Table(const MachineInstr *MI) {
1089  unsigned Opcode = MI->getOpcode();
1090  int OpNum = (Opcode == ARM::t2BR_JT) ? 2 : 1;
1091  const MachineOperand &MO1 = MI->getOperand(OpNum);
1092  const MachineOperand &MO2 = MI->getOperand(OpNum+1); // Unique Id
1093  unsigned JTI = MO1.getIndex();
1094
1095  MCSymbol *JTISymbol = GetARMJTIPICJumpTableLabel2(JTI, MO2.getImm());
1096  OutStreamer.EmitLabel(JTISymbol);
1097
1098  // Emit each entry of the table.
1099  const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo();
1100  const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
1101  const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs;
1102  unsigned OffsetWidth = 4;
1103  if (MI->getOpcode() == ARM::t2TBB_JT) {
1104    OffsetWidth = 1;
1105    // Mark the jump table as data-in-code.
1106    OutStreamer.EmitDataRegion(MCDR_DataRegionJT8);
1107  } else if (MI->getOpcode() == ARM::t2TBH_JT) {
1108    OffsetWidth = 2;
1109    // Mark the jump table as data-in-code.
1110    OutStreamer.EmitDataRegion(MCDR_DataRegionJT16);
1111  }
1112
1113  for (unsigned i = 0, e = JTBBs.size(); i != e; ++i) {
1114    MachineBasicBlock *MBB = JTBBs[i];
1115    const MCExpr *MBBSymbolExpr = MCSymbolRefExpr::Create(MBB->getSymbol(),
1116                                                      OutContext);
1117    // If this isn't a TBB or TBH, the entries are direct branch instructions.
1118    if (OffsetWidth == 4) {
1119      OutStreamer.EmitInstruction(MCInstBuilder(ARM::t2B)
1120        .addExpr(MBBSymbolExpr)
1121        .addImm(ARMCC::AL)
1122        .addReg(0));
1123      continue;
1124    }
1125    // Otherwise it's an offset from the dispatch instruction. Construct an
1126    // MCExpr for the entry. We want a value of the form:
1127    // (BasicBlockAddr - TableBeginAddr) / 2
1128    //
1129    // For example, a TBB table with entries jumping to basic blocks BB0 and BB1
1130    // would look like:
1131    // LJTI_0_0:
1132    //    .byte (LBB0 - LJTI_0_0) / 2
1133    //    .byte (LBB1 - LJTI_0_0) / 2
1134    const MCExpr *Expr =
1135      MCBinaryExpr::CreateSub(MBBSymbolExpr,
1136                              MCSymbolRefExpr::Create(JTISymbol, OutContext),
1137                              OutContext);
1138    Expr = MCBinaryExpr::CreateDiv(Expr, MCConstantExpr::Create(2, OutContext),
1139                                   OutContext);
1140    OutStreamer.EmitValue(Expr, OffsetWidth);
1141  }
1142  // Mark the end of jump table data-in-code region. 32-bit offsets use
1143  // actual branch instructions here, so we don't mark those as a data-region
1144  // at all.
1145  if (OffsetWidth != 4)
1146    OutStreamer.EmitDataRegion(MCDR_DataRegionEnd);
1147}
1148
1149void ARMAsmPrinter::EmitUnwindingInstruction(const MachineInstr *MI) {
1150  assert(MI->getFlag(MachineInstr::FrameSetup) &&
1151      "Only instruction which are involved into frame setup code are allowed");
1152
1153  MCTargetStreamer &TS = OutStreamer.getTargetStreamer();
1154  ARMTargetStreamer &ATS = static_cast<ARMTargetStreamer &>(TS);
1155  const MachineFunction &MF = *MI->getParent()->getParent();
1156  const TargetRegisterInfo *RegInfo = MF.getTarget().getRegisterInfo();
1157  const ARMFunctionInfo &AFI = *MF.getInfo<ARMFunctionInfo>();
1158
1159  unsigned FramePtr = RegInfo->getFrameRegister(MF);
1160  unsigned Opc = MI->getOpcode();
1161  unsigned SrcReg, DstReg;
1162
1163  if (Opc == ARM::tPUSH || Opc == ARM::tLDRpci) {
1164    // Two special cases:
1165    // 1) tPUSH does not have src/dst regs.
1166    // 2) for Thumb1 code we sometimes materialize the constant via constpool
1167    // load. Yes, this is pretty fragile, but for now I don't see better
1168    // way... :(
1169    SrcReg = DstReg = ARM::SP;
1170  } else {
1171    SrcReg = MI->getOperand(1).getReg();
1172    DstReg = MI->getOperand(0).getReg();
1173  }
1174
1175  // Try to figure out the unwinding opcode out of src / dst regs.
1176  if (MI->mayStore()) {
1177    // Register saves.
1178    assert(DstReg == ARM::SP &&
1179           "Only stack pointer as a destination reg is supported");
1180
1181    SmallVector<unsigned, 4> RegList;
1182    // Skip src & dst reg, and pred ops.
1183    unsigned StartOp = 2 + 2;
1184    // Use all the operands.
1185    unsigned NumOffset = 0;
1186
1187    switch (Opc) {
1188    default:
1189      MI->dump();
1190      llvm_unreachable("Unsupported opcode for unwinding information");
1191    case ARM::tPUSH:
1192      // Special case here: no src & dst reg, but two extra imp ops.
1193      StartOp = 2; NumOffset = 2;
1194    case ARM::STMDB_UPD:
1195    case ARM::t2STMDB_UPD:
1196    case ARM::VSTMDDB_UPD:
1197      assert(SrcReg == ARM::SP &&
1198             "Only stack pointer as a source reg is supported");
1199      for (unsigned i = StartOp, NumOps = MI->getNumOperands() - NumOffset;
1200           i != NumOps; ++i) {
1201        const MachineOperand &MO = MI->getOperand(i);
1202        // Actually, there should never be any impdef stuff here. Skip it
1203        // temporary to workaround PR11902.
1204        if (MO.isImplicit())
1205          continue;
1206        RegList.push_back(MO.getReg());
1207      }
1208      break;
1209    case ARM::STR_PRE_IMM:
1210    case ARM::STR_PRE_REG:
1211    case ARM::t2STR_PRE:
1212      assert(MI->getOperand(2).getReg() == ARM::SP &&
1213             "Only stack pointer as a source reg is supported");
1214      RegList.push_back(SrcReg);
1215      break;
1216    }
1217    ATS.emitRegSave(RegList, Opc == ARM::VSTMDDB_UPD);
1218  } else {
1219    // Changes of stack / frame pointer.
1220    if (SrcReg == ARM::SP) {
1221      int64_t Offset = 0;
1222      switch (Opc) {
1223      default:
1224        MI->dump();
1225        llvm_unreachable("Unsupported opcode for unwinding information");
1226      case ARM::MOVr:
1227      case ARM::tMOVr:
1228        Offset = 0;
1229        break;
1230      case ARM::ADDri:
1231        Offset = -MI->getOperand(2).getImm();
1232        break;
1233      case ARM::SUBri:
1234      case ARM::t2SUBri:
1235        Offset = MI->getOperand(2).getImm();
1236        break;
1237      case ARM::tSUBspi:
1238        Offset = MI->getOperand(2).getImm()*4;
1239        break;
1240      case ARM::tADDspi:
1241      case ARM::tADDrSPi:
1242        Offset = -MI->getOperand(2).getImm()*4;
1243        break;
1244      case ARM::tLDRpci: {
1245        // Grab the constpool index and check, whether it corresponds to
1246        // original or cloned constpool entry.
1247        unsigned CPI = MI->getOperand(1).getIndex();
1248        const MachineConstantPool *MCP = MF.getConstantPool();
1249        if (CPI >= MCP->getConstants().size())
1250          CPI = AFI.getOriginalCPIdx(CPI);
1251        assert(CPI != -1U && "Invalid constpool index");
1252
1253        // Derive the actual offset.
1254        const MachineConstantPoolEntry &CPE = MCP->getConstants()[CPI];
1255        assert(!CPE.isMachineConstantPoolEntry() && "Invalid constpool entry");
1256        // FIXME: Check for user, it should be "add" instruction!
1257        Offset = -cast<ConstantInt>(CPE.Val.ConstVal)->getSExtValue();
1258        break;
1259      }
1260      }
1261
1262      if (DstReg == FramePtr && FramePtr != ARM::SP)
1263        // Set-up of the frame pointer. Positive values correspond to "add"
1264        // instruction.
1265        ATS.emitSetFP(FramePtr, ARM::SP, -Offset);
1266      else if (DstReg == ARM::SP) {
1267        // Change of SP by an offset. Positive values correspond to "sub"
1268        // instruction.
1269        ATS.emitPad(Offset);
1270      } else {
1271        MI->dump();
1272        llvm_unreachable("Unsupported opcode for unwinding information");
1273      }
1274    } else if (DstReg == ARM::SP) {
1275      // FIXME: .movsp goes here
1276      MI->dump();
1277      llvm_unreachable("Unsupported opcode for unwinding information");
1278    }
1279    else {
1280      MI->dump();
1281      llvm_unreachable("Unsupported opcode for unwinding information");
1282    }
1283  }
1284}
1285
1286extern cl::opt<bool> EnableARMEHABI;
1287
1288// Simple pseudo-instructions have their lowering (with expansion to real
1289// instructions) auto-generated.
1290#include "ARMGenMCPseudoLowering.inc"
1291
1292void ARMAsmPrinter::EmitInstruction(const MachineInstr *MI) {
1293  // If we just ended a constant pool, mark it as such.
1294  if (InConstantPool && MI->getOpcode() != ARM::CONSTPOOL_ENTRY) {
1295    OutStreamer.EmitDataRegion(MCDR_DataRegionEnd);
1296    InConstantPool = false;
1297  }
1298
1299  // Emit unwinding stuff for frame-related instructions
1300  if (EnableARMEHABI && MI->getFlag(MachineInstr::FrameSetup))
1301    EmitUnwindingInstruction(MI);
1302
1303  // Do any auto-generated pseudo lowerings.
1304  if (emitPseudoExpansionLowering(OutStreamer, MI))
1305    return;
1306
1307  assert(!convertAddSubFlagsOpcode(MI->getOpcode()) &&
1308         "Pseudo flag setting opcode should be expanded early");
1309
1310  // Check for manual lowerings.
1311  unsigned Opc = MI->getOpcode();
1312  switch (Opc) {
1313  case ARM::t2MOVi32imm: llvm_unreachable("Should be lowered by thumb2it pass");
1314  case ARM::DBG_VALUE: llvm_unreachable("Should be handled by generic printing");
1315  case ARM::LEApcrel:
1316  case ARM::tLEApcrel:
1317  case ARM::t2LEApcrel: {
1318    // FIXME: Need to also handle globals and externals
1319    MCSymbol *CPISymbol = GetCPISymbol(MI->getOperand(1).getIndex());
1320    OutStreamer.EmitInstruction(MCInstBuilder(MI->getOpcode() ==
1321                                              ARM::t2LEApcrel ? ARM::t2ADR
1322                  : (MI->getOpcode() == ARM::tLEApcrel ? ARM::tADR
1323                     : ARM::ADR))
1324      .addReg(MI->getOperand(0).getReg())
1325      .addExpr(MCSymbolRefExpr::Create(CPISymbol, OutContext))
1326      // Add predicate operands.
1327      .addImm(MI->getOperand(2).getImm())
1328      .addReg(MI->getOperand(3).getReg()));
1329    return;
1330  }
1331  case ARM::LEApcrelJT:
1332  case ARM::tLEApcrelJT:
1333  case ARM::t2LEApcrelJT: {
1334    MCSymbol *JTIPICSymbol =
1335      GetARMJTIPICJumpTableLabel2(MI->getOperand(1).getIndex(),
1336                                  MI->getOperand(2).getImm());
1337    OutStreamer.EmitInstruction(MCInstBuilder(MI->getOpcode() ==
1338                                              ARM::t2LEApcrelJT ? ARM::t2ADR
1339                  : (MI->getOpcode() == ARM::tLEApcrelJT ? ARM::tADR
1340                     : ARM::ADR))
1341      .addReg(MI->getOperand(0).getReg())
1342      .addExpr(MCSymbolRefExpr::Create(JTIPICSymbol, OutContext))
1343      // Add predicate operands.
1344      .addImm(MI->getOperand(3).getImm())
1345      .addReg(MI->getOperand(4).getReg()));
1346    return;
1347  }
1348  // Darwin call instructions are just normal call instructions with different
1349  // clobber semantics (they clobber R9).
1350  case ARM::BX_CALL: {
1351    OutStreamer.EmitInstruction(MCInstBuilder(ARM::MOVr)
1352      .addReg(ARM::LR)
1353      .addReg(ARM::PC)
1354      // Add predicate operands.
1355      .addImm(ARMCC::AL)
1356      .addReg(0)
1357      // Add 's' bit operand (always reg0 for this)
1358      .addReg(0));
1359
1360    OutStreamer.EmitInstruction(MCInstBuilder(ARM::BX)
1361      .addReg(MI->getOperand(0).getReg()));
1362    return;
1363  }
1364  case ARM::tBX_CALL: {
1365    OutStreamer.EmitInstruction(MCInstBuilder(ARM::tMOVr)
1366      .addReg(ARM::LR)
1367      .addReg(ARM::PC)
1368      // Add predicate operands.
1369      .addImm(ARMCC::AL)
1370      .addReg(0));
1371
1372    OutStreamer.EmitInstruction(MCInstBuilder(ARM::tBX)
1373      .addReg(MI->getOperand(0).getReg())
1374      // Add predicate operands.
1375      .addImm(ARMCC::AL)
1376      .addReg(0));
1377    return;
1378  }
1379  case ARM::BMOVPCRX_CALL: {
1380    OutStreamer.EmitInstruction(MCInstBuilder(ARM::MOVr)
1381      .addReg(ARM::LR)
1382      .addReg(ARM::PC)
1383      // Add predicate operands.
1384      .addImm(ARMCC::AL)
1385      .addReg(0)
1386      // Add 's' bit operand (always reg0 for this)
1387      .addReg(0));
1388
1389    OutStreamer.EmitInstruction(MCInstBuilder(ARM::MOVr)
1390      .addReg(ARM::PC)
1391      .addReg(MI->getOperand(0).getReg())
1392      // Add predicate operands.
1393      .addImm(ARMCC::AL)
1394      .addReg(0)
1395      // Add 's' bit operand (always reg0 for this)
1396      .addReg(0));
1397    return;
1398  }
1399  case ARM::BMOVPCB_CALL: {
1400    OutStreamer.EmitInstruction(MCInstBuilder(ARM::MOVr)
1401      .addReg(ARM::LR)
1402      .addReg(ARM::PC)
1403      // Add predicate operands.
1404      .addImm(ARMCC::AL)
1405      .addReg(0)
1406      // Add 's' bit operand (always reg0 for this)
1407      .addReg(0));
1408
1409    const GlobalValue *GV = MI->getOperand(0).getGlobal();
1410    MCSymbol *GVSym = Mang->getSymbol(GV);
1411    const MCExpr *GVSymExpr = MCSymbolRefExpr::Create(GVSym, OutContext);
1412    OutStreamer.EmitInstruction(MCInstBuilder(ARM::Bcc)
1413      .addExpr(GVSymExpr)
1414      // Add predicate operands.
1415      .addImm(ARMCC::AL)
1416      .addReg(0));
1417    return;
1418  }
1419  case ARM::MOVi16_ga_pcrel:
1420  case ARM::t2MOVi16_ga_pcrel: {
1421    MCInst TmpInst;
1422    TmpInst.setOpcode(Opc == ARM::MOVi16_ga_pcrel? ARM::MOVi16 : ARM::t2MOVi16);
1423    TmpInst.addOperand(MCOperand::CreateReg(MI->getOperand(0).getReg()));
1424
1425    unsigned TF = MI->getOperand(1).getTargetFlags();
1426    bool isPIC = TF == ARMII::MO_LO16_NONLAZY_PIC;
1427    const GlobalValue *GV = MI->getOperand(1).getGlobal();
1428    MCSymbol *GVSym = GetARMGVSymbol(GV);
1429    const MCExpr *GVSymExpr = MCSymbolRefExpr::Create(GVSym, OutContext);
1430    if (isPIC) {
1431      MCSymbol *LabelSym = getPICLabel(MAI->getPrivateGlobalPrefix(),
1432                                       getFunctionNumber(),
1433                                       MI->getOperand(2).getImm(), OutContext);
1434      const MCExpr *LabelSymExpr= MCSymbolRefExpr::Create(LabelSym, OutContext);
1435      unsigned PCAdj = (Opc == ARM::MOVi16_ga_pcrel) ? 8 : 4;
1436      const MCExpr *PCRelExpr =
1437        ARMMCExpr::CreateLower16(MCBinaryExpr::CreateSub(GVSymExpr,
1438                                  MCBinaryExpr::CreateAdd(LabelSymExpr,
1439                                      MCConstantExpr::Create(PCAdj, OutContext),
1440                                          OutContext), OutContext), OutContext);
1441      TmpInst.addOperand(MCOperand::CreateExpr(PCRelExpr));
1442    } else {
1443      const MCExpr *RefExpr= ARMMCExpr::CreateLower16(GVSymExpr, OutContext);
1444      TmpInst.addOperand(MCOperand::CreateExpr(RefExpr));
1445    }
1446
1447    // Add predicate operands.
1448    TmpInst.addOperand(MCOperand::CreateImm(ARMCC::AL));
1449    TmpInst.addOperand(MCOperand::CreateReg(0));
1450    // Add 's' bit operand (always reg0 for this)
1451    TmpInst.addOperand(MCOperand::CreateReg(0));
1452    OutStreamer.EmitInstruction(TmpInst);
1453    return;
1454  }
1455  case ARM::MOVTi16_ga_pcrel:
1456  case ARM::t2MOVTi16_ga_pcrel: {
1457    MCInst TmpInst;
1458    TmpInst.setOpcode(Opc == ARM::MOVTi16_ga_pcrel
1459                      ? ARM::MOVTi16 : ARM::t2MOVTi16);
1460    TmpInst.addOperand(MCOperand::CreateReg(MI->getOperand(0).getReg()));
1461    TmpInst.addOperand(MCOperand::CreateReg(MI->getOperand(1).getReg()));
1462
1463    unsigned TF = MI->getOperand(2).getTargetFlags();
1464    bool isPIC = TF == ARMII::MO_HI16_NONLAZY_PIC;
1465    const GlobalValue *GV = MI->getOperand(2).getGlobal();
1466    MCSymbol *GVSym = GetARMGVSymbol(GV);
1467    const MCExpr *GVSymExpr = MCSymbolRefExpr::Create(GVSym, OutContext);
1468    if (isPIC) {
1469      MCSymbol *LabelSym = getPICLabel(MAI->getPrivateGlobalPrefix(),
1470                                       getFunctionNumber(),
1471                                       MI->getOperand(3).getImm(), OutContext);
1472      const MCExpr *LabelSymExpr= MCSymbolRefExpr::Create(LabelSym, OutContext);
1473      unsigned PCAdj = (Opc == ARM::MOVTi16_ga_pcrel) ? 8 : 4;
1474      const MCExpr *PCRelExpr =
1475        ARMMCExpr::CreateUpper16(MCBinaryExpr::CreateSub(GVSymExpr,
1476                                   MCBinaryExpr::CreateAdd(LabelSymExpr,
1477                                      MCConstantExpr::Create(PCAdj, OutContext),
1478                                          OutContext), OutContext), OutContext);
1479      TmpInst.addOperand(MCOperand::CreateExpr(PCRelExpr));
1480    } else {
1481      const MCExpr *RefExpr= ARMMCExpr::CreateUpper16(GVSymExpr, OutContext);
1482      TmpInst.addOperand(MCOperand::CreateExpr(RefExpr));
1483    }
1484    // Add predicate operands.
1485    TmpInst.addOperand(MCOperand::CreateImm(ARMCC::AL));
1486    TmpInst.addOperand(MCOperand::CreateReg(0));
1487    // Add 's' bit operand (always reg0 for this)
1488    TmpInst.addOperand(MCOperand::CreateReg(0));
1489    OutStreamer.EmitInstruction(TmpInst);
1490    return;
1491  }
1492  case ARM::tPICADD: {
1493    // This is a pseudo op for a label + instruction sequence, which looks like:
1494    // LPC0:
1495    //     add r0, pc
1496    // This adds the address of LPC0 to r0.
1497
1498    // Emit the label.
1499    OutStreamer.EmitLabel(getPICLabel(MAI->getPrivateGlobalPrefix(),
1500                          getFunctionNumber(), MI->getOperand(2).getImm(),
1501                          OutContext));
1502
1503    // Form and emit the add.
1504    OutStreamer.EmitInstruction(MCInstBuilder(ARM::tADDhirr)
1505      .addReg(MI->getOperand(0).getReg())
1506      .addReg(MI->getOperand(0).getReg())
1507      .addReg(ARM::PC)
1508      // Add predicate operands.
1509      .addImm(ARMCC::AL)
1510      .addReg(0));
1511    return;
1512  }
1513  case ARM::PICADD: {
1514    // This is a pseudo op for a label + instruction sequence, which looks like:
1515    // LPC0:
1516    //     add r0, pc, r0
1517    // This adds the address of LPC0 to r0.
1518
1519    // Emit the label.
1520    OutStreamer.EmitLabel(getPICLabel(MAI->getPrivateGlobalPrefix(),
1521                          getFunctionNumber(), MI->getOperand(2).getImm(),
1522                          OutContext));
1523
1524    // Form and emit the add.
1525    OutStreamer.EmitInstruction(MCInstBuilder(ARM::ADDrr)
1526      .addReg(MI->getOperand(0).getReg())
1527      .addReg(ARM::PC)
1528      .addReg(MI->getOperand(1).getReg())
1529      // Add predicate operands.
1530      .addImm(MI->getOperand(3).getImm())
1531      .addReg(MI->getOperand(4).getReg())
1532      // Add 's' bit operand (always reg0 for this)
1533      .addReg(0));
1534    return;
1535  }
1536  case ARM::PICSTR:
1537  case ARM::PICSTRB:
1538  case ARM::PICSTRH:
1539  case ARM::PICLDR:
1540  case ARM::PICLDRB:
1541  case ARM::PICLDRH:
1542  case ARM::PICLDRSB:
1543  case ARM::PICLDRSH: {
1544    // This is a pseudo op for a label + instruction sequence, which looks like:
1545    // LPC0:
1546    //     OP r0, [pc, r0]
1547    // The LCP0 label is referenced by a constant pool entry in order to get
1548    // a PC-relative address at the ldr instruction.
1549
1550    // Emit the label.
1551    OutStreamer.EmitLabel(getPICLabel(MAI->getPrivateGlobalPrefix(),
1552                          getFunctionNumber(), MI->getOperand(2).getImm(),
1553                          OutContext));
1554
1555    // Form and emit the load
1556    unsigned Opcode;
1557    switch (MI->getOpcode()) {
1558    default:
1559      llvm_unreachable("Unexpected opcode!");
1560    case ARM::PICSTR:   Opcode = ARM::STRrs; break;
1561    case ARM::PICSTRB:  Opcode = ARM::STRBrs; break;
1562    case ARM::PICSTRH:  Opcode = ARM::STRH; break;
1563    case ARM::PICLDR:   Opcode = ARM::LDRrs; break;
1564    case ARM::PICLDRB:  Opcode = ARM::LDRBrs; break;
1565    case ARM::PICLDRH:  Opcode = ARM::LDRH; break;
1566    case ARM::PICLDRSB: Opcode = ARM::LDRSB; break;
1567    case ARM::PICLDRSH: Opcode = ARM::LDRSH; break;
1568    }
1569    OutStreamer.EmitInstruction(MCInstBuilder(Opcode)
1570      .addReg(MI->getOperand(0).getReg())
1571      .addReg(ARM::PC)
1572      .addReg(MI->getOperand(1).getReg())
1573      .addImm(0)
1574      // Add predicate operands.
1575      .addImm(MI->getOperand(3).getImm())
1576      .addReg(MI->getOperand(4).getReg()));
1577
1578    return;
1579  }
1580  case ARM::CONSTPOOL_ENTRY: {
1581    /// CONSTPOOL_ENTRY - This instruction represents a floating constant pool
1582    /// in the function.  The first operand is the ID# for this instruction, the
1583    /// second is the index into the MachineConstantPool that this is, the third
1584    /// is the size in bytes of this constant pool entry.
1585    /// The required alignment is specified on the basic block holding this MI.
1586    unsigned LabelId = (unsigned)MI->getOperand(0).getImm();
1587    unsigned CPIdx   = (unsigned)MI->getOperand(1).getIndex();
1588
1589    // If this is the first entry of the pool, mark it.
1590    if (!InConstantPool) {
1591      OutStreamer.EmitDataRegion(MCDR_DataRegion);
1592      InConstantPool = true;
1593    }
1594
1595    OutStreamer.EmitLabel(GetCPISymbol(LabelId));
1596
1597    const MachineConstantPoolEntry &MCPE = MCP->getConstants()[CPIdx];
1598    if (MCPE.isMachineConstantPoolEntry())
1599      EmitMachineConstantPoolValue(MCPE.Val.MachineCPVal);
1600    else
1601      EmitGlobalConstant(MCPE.Val.ConstVal);
1602    return;
1603  }
1604  case ARM::t2BR_JT: {
1605    // Lower and emit the instruction itself, then the jump table following it.
1606    OutStreamer.EmitInstruction(MCInstBuilder(ARM::tMOVr)
1607      .addReg(ARM::PC)
1608      .addReg(MI->getOperand(0).getReg())
1609      // Add predicate operands.
1610      .addImm(ARMCC::AL)
1611      .addReg(0));
1612
1613    // Output the data for the jump table itself
1614    EmitJump2Table(MI);
1615    return;
1616  }
1617  case ARM::t2TBB_JT: {
1618    // Lower and emit the instruction itself, then the jump table following it.
1619    OutStreamer.EmitInstruction(MCInstBuilder(ARM::t2TBB)
1620      .addReg(ARM::PC)
1621      .addReg(MI->getOperand(0).getReg())
1622      // Add predicate operands.
1623      .addImm(ARMCC::AL)
1624      .addReg(0));
1625
1626    // Output the data for the jump table itself
1627    EmitJump2Table(MI);
1628    // Make sure the next instruction is 2-byte aligned.
1629    EmitAlignment(1);
1630    return;
1631  }
1632  case ARM::t2TBH_JT: {
1633    // Lower and emit the instruction itself, then the jump table following it.
1634    OutStreamer.EmitInstruction(MCInstBuilder(ARM::t2TBH)
1635      .addReg(ARM::PC)
1636      .addReg(MI->getOperand(0).getReg())
1637      // Add predicate operands.
1638      .addImm(ARMCC::AL)
1639      .addReg(0));
1640
1641    // Output the data for the jump table itself
1642    EmitJump2Table(MI);
1643    return;
1644  }
1645  case ARM::tBR_JTr:
1646  case ARM::BR_JTr: {
1647    // Lower and emit the instruction itself, then the jump table following it.
1648    // mov pc, target
1649    MCInst TmpInst;
1650    unsigned Opc = MI->getOpcode() == ARM::BR_JTr ?
1651      ARM::MOVr : ARM::tMOVr;
1652    TmpInst.setOpcode(Opc);
1653    TmpInst.addOperand(MCOperand::CreateReg(ARM::PC));
1654    TmpInst.addOperand(MCOperand::CreateReg(MI->getOperand(0).getReg()));
1655    // Add predicate operands.
1656    TmpInst.addOperand(MCOperand::CreateImm(ARMCC::AL));
1657    TmpInst.addOperand(MCOperand::CreateReg(0));
1658    // Add 's' bit operand (always reg0 for this)
1659    if (Opc == ARM::MOVr)
1660      TmpInst.addOperand(MCOperand::CreateReg(0));
1661    OutStreamer.EmitInstruction(TmpInst);
1662
1663    // Make sure the Thumb jump table is 4-byte aligned.
1664    if (Opc == ARM::tMOVr)
1665      EmitAlignment(2);
1666
1667    // Output the data for the jump table itself
1668    EmitJumpTable(MI);
1669    return;
1670  }
1671  case ARM::BR_JTm: {
1672    // Lower and emit the instruction itself, then the jump table following it.
1673    // ldr pc, target
1674    MCInst TmpInst;
1675    if (MI->getOperand(1).getReg() == 0) {
1676      // literal offset
1677      TmpInst.setOpcode(ARM::LDRi12);
1678      TmpInst.addOperand(MCOperand::CreateReg(ARM::PC));
1679      TmpInst.addOperand(MCOperand::CreateReg(MI->getOperand(0).getReg()));
1680      TmpInst.addOperand(MCOperand::CreateImm(MI->getOperand(2).getImm()));
1681    } else {
1682      TmpInst.setOpcode(ARM::LDRrs);
1683      TmpInst.addOperand(MCOperand::CreateReg(ARM::PC));
1684      TmpInst.addOperand(MCOperand::CreateReg(MI->getOperand(0).getReg()));
1685      TmpInst.addOperand(MCOperand::CreateReg(MI->getOperand(1).getReg()));
1686      TmpInst.addOperand(MCOperand::CreateImm(0));
1687    }
1688    // Add predicate operands.
1689    TmpInst.addOperand(MCOperand::CreateImm(ARMCC::AL));
1690    TmpInst.addOperand(MCOperand::CreateReg(0));
1691    OutStreamer.EmitInstruction(TmpInst);
1692
1693    // Output the data for the jump table itself
1694    EmitJumpTable(MI);
1695    return;
1696  }
1697  case ARM::BR_JTadd: {
1698    // Lower and emit the instruction itself, then the jump table following it.
1699    // add pc, target, idx
1700    OutStreamer.EmitInstruction(MCInstBuilder(ARM::ADDrr)
1701      .addReg(ARM::PC)
1702      .addReg(MI->getOperand(0).getReg())
1703      .addReg(MI->getOperand(1).getReg())
1704      // Add predicate operands.
1705      .addImm(ARMCC::AL)
1706      .addReg(0)
1707      // Add 's' bit operand (always reg0 for this)
1708      .addReg(0));
1709
1710    // Output the data for the jump table itself
1711    EmitJumpTable(MI);
1712    return;
1713  }
1714  case ARM::TRAP: {
1715    // Non-Darwin binutils don't yet support the "trap" mnemonic.
1716    // FIXME: Remove this special case when they do.
1717    if (!Subtarget->isTargetDarwin()) {
1718      //.long 0xe7ffdefe @ trap
1719      uint32_t Val = 0xe7ffdefeUL;
1720      OutStreamer.AddComment("trap");
1721      OutStreamer.EmitIntValue(Val, 4);
1722      return;
1723    }
1724    break;
1725  }
1726  case ARM::TRAPNaCl: {
1727    //.long 0xe7fedef0 @ trap
1728    uint32_t Val = 0xe7fedef0UL;
1729    OutStreamer.AddComment("trap");
1730    OutStreamer.EmitIntValue(Val, 4);
1731    return;
1732  }
1733  case ARM::tTRAP: {
1734    // Non-Darwin binutils don't yet support the "trap" mnemonic.
1735    // FIXME: Remove this special case when they do.
1736    if (!Subtarget->isTargetDarwin()) {
1737      //.short 57086 @ trap
1738      uint16_t Val = 0xdefe;
1739      OutStreamer.AddComment("trap");
1740      OutStreamer.EmitIntValue(Val, 2);
1741      return;
1742    }
1743    break;
1744  }
1745  case ARM::t2Int_eh_sjlj_setjmp:
1746  case ARM::t2Int_eh_sjlj_setjmp_nofp:
1747  case ARM::tInt_eh_sjlj_setjmp: {
1748    // Two incoming args: GPR:$src, GPR:$val
1749    // mov $val, pc
1750    // adds $val, #7
1751    // str $val, [$src, #4]
1752    // movs r0, #0
1753    // b 1f
1754    // movs r0, #1
1755    // 1:
1756    unsigned SrcReg = MI->getOperand(0).getReg();
1757    unsigned ValReg = MI->getOperand(1).getReg();
1758    MCSymbol *Label = GetARMSJLJEHLabel();
1759    OutStreamer.AddComment("eh_setjmp begin");
1760    OutStreamer.EmitInstruction(MCInstBuilder(ARM::tMOVr)
1761      .addReg(ValReg)
1762      .addReg(ARM::PC)
1763      // Predicate.
1764      .addImm(ARMCC::AL)
1765      .addReg(0));
1766
1767    OutStreamer.EmitInstruction(MCInstBuilder(ARM::tADDi3)
1768      .addReg(ValReg)
1769      // 's' bit operand
1770      .addReg(ARM::CPSR)
1771      .addReg(ValReg)
1772      .addImm(7)
1773      // Predicate.
1774      .addImm(ARMCC::AL)
1775      .addReg(0));
1776
1777    OutStreamer.EmitInstruction(MCInstBuilder(ARM::tSTRi)
1778      .addReg(ValReg)
1779      .addReg(SrcReg)
1780      // The offset immediate is #4. The operand value is scaled by 4 for the
1781      // tSTR instruction.
1782      .addImm(1)
1783      // Predicate.
1784      .addImm(ARMCC::AL)
1785      .addReg(0));
1786
1787    OutStreamer.EmitInstruction(MCInstBuilder(ARM::tMOVi8)
1788      .addReg(ARM::R0)
1789      .addReg(ARM::CPSR)
1790      .addImm(0)
1791      // Predicate.
1792      .addImm(ARMCC::AL)
1793      .addReg(0));
1794
1795    const MCExpr *SymbolExpr = MCSymbolRefExpr::Create(Label, OutContext);
1796    OutStreamer.EmitInstruction(MCInstBuilder(ARM::tB)
1797      .addExpr(SymbolExpr)
1798      .addImm(ARMCC::AL)
1799      .addReg(0));
1800
1801    OutStreamer.AddComment("eh_setjmp end");
1802    OutStreamer.EmitInstruction(MCInstBuilder(ARM::tMOVi8)
1803      .addReg(ARM::R0)
1804      .addReg(ARM::CPSR)
1805      .addImm(1)
1806      // Predicate.
1807      .addImm(ARMCC::AL)
1808      .addReg(0));
1809
1810    OutStreamer.EmitLabel(Label);
1811    return;
1812  }
1813
1814  case ARM::Int_eh_sjlj_setjmp_nofp:
1815  case ARM::Int_eh_sjlj_setjmp: {
1816    // Two incoming args: GPR:$src, GPR:$val
1817    // add $val, pc, #8
1818    // str $val, [$src, #+4]
1819    // mov r0, #0
1820    // add pc, pc, #0
1821    // mov r0, #1
1822    unsigned SrcReg = MI->getOperand(0).getReg();
1823    unsigned ValReg = MI->getOperand(1).getReg();
1824
1825    OutStreamer.AddComment("eh_setjmp begin");
1826    OutStreamer.EmitInstruction(MCInstBuilder(ARM::ADDri)
1827      .addReg(ValReg)
1828      .addReg(ARM::PC)
1829      .addImm(8)
1830      // Predicate.
1831      .addImm(ARMCC::AL)
1832      .addReg(0)
1833      // 's' bit operand (always reg0 for this).
1834      .addReg(0));
1835
1836    OutStreamer.EmitInstruction(MCInstBuilder(ARM::STRi12)
1837      .addReg(ValReg)
1838      .addReg(SrcReg)
1839      .addImm(4)
1840      // Predicate.
1841      .addImm(ARMCC::AL)
1842      .addReg(0));
1843
1844    OutStreamer.EmitInstruction(MCInstBuilder(ARM::MOVi)
1845      .addReg(ARM::R0)
1846      .addImm(0)
1847      // Predicate.
1848      .addImm(ARMCC::AL)
1849      .addReg(0)
1850      // 's' bit operand (always reg0 for this).
1851      .addReg(0));
1852
1853    OutStreamer.EmitInstruction(MCInstBuilder(ARM::ADDri)
1854      .addReg(ARM::PC)
1855      .addReg(ARM::PC)
1856      .addImm(0)
1857      // Predicate.
1858      .addImm(ARMCC::AL)
1859      .addReg(0)
1860      // 's' bit operand (always reg0 for this).
1861      .addReg(0));
1862
1863    OutStreamer.AddComment("eh_setjmp end");
1864    OutStreamer.EmitInstruction(MCInstBuilder(ARM::MOVi)
1865      .addReg(ARM::R0)
1866      .addImm(1)
1867      // Predicate.
1868      .addImm(ARMCC::AL)
1869      .addReg(0)
1870      // 's' bit operand (always reg0 for this).
1871      .addReg(0));
1872    return;
1873  }
1874  case ARM::Int_eh_sjlj_longjmp: {
1875    // ldr sp, [$src, #8]
1876    // ldr $scratch, [$src, #4]
1877    // ldr r7, [$src]
1878    // bx $scratch
1879    unsigned SrcReg = MI->getOperand(0).getReg();
1880    unsigned ScratchReg = MI->getOperand(1).getReg();
1881    OutStreamer.EmitInstruction(MCInstBuilder(ARM::LDRi12)
1882      .addReg(ARM::SP)
1883      .addReg(SrcReg)
1884      .addImm(8)
1885      // Predicate.
1886      .addImm(ARMCC::AL)
1887      .addReg(0));
1888
1889    OutStreamer.EmitInstruction(MCInstBuilder(ARM::LDRi12)
1890      .addReg(ScratchReg)
1891      .addReg(SrcReg)
1892      .addImm(4)
1893      // Predicate.
1894      .addImm(ARMCC::AL)
1895      .addReg(0));
1896
1897    OutStreamer.EmitInstruction(MCInstBuilder(ARM::LDRi12)
1898      .addReg(ARM::R7)
1899      .addReg(SrcReg)
1900      .addImm(0)
1901      // Predicate.
1902      .addImm(ARMCC::AL)
1903      .addReg(0));
1904
1905    OutStreamer.EmitInstruction(MCInstBuilder(ARM::BX)
1906      .addReg(ScratchReg)
1907      // Predicate.
1908      .addImm(ARMCC::AL)
1909      .addReg(0));
1910    return;
1911  }
1912  case ARM::tInt_eh_sjlj_longjmp: {
1913    // ldr $scratch, [$src, #8]
1914    // mov sp, $scratch
1915    // ldr $scratch, [$src, #4]
1916    // ldr r7, [$src]
1917    // bx $scratch
1918    unsigned SrcReg = MI->getOperand(0).getReg();
1919    unsigned ScratchReg = MI->getOperand(1).getReg();
1920    OutStreamer.EmitInstruction(MCInstBuilder(ARM::tLDRi)
1921      .addReg(ScratchReg)
1922      .addReg(SrcReg)
1923      // The offset immediate is #8. The operand value is scaled by 4 for the
1924      // tLDR instruction.
1925      .addImm(2)
1926      // Predicate.
1927      .addImm(ARMCC::AL)
1928      .addReg(0));
1929
1930    OutStreamer.EmitInstruction(MCInstBuilder(ARM::tMOVr)
1931      .addReg(ARM::SP)
1932      .addReg(ScratchReg)
1933      // Predicate.
1934      .addImm(ARMCC::AL)
1935      .addReg(0));
1936
1937    OutStreamer.EmitInstruction(MCInstBuilder(ARM::tLDRi)
1938      .addReg(ScratchReg)
1939      .addReg(SrcReg)
1940      .addImm(1)
1941      // Predicate.
1942      .addImm(ARMCC::AL)
1943      .addReg(0));
1944
1945    OutStreamer.EmitInstruction(MCInstBuilder(ARM::tLDRi)
1946      .addReg(ARM::R7)
1947      .addReg(SrcReg)
1948      .addImm(0)
1949      // Predicate.
1950      .addImm(ARMCC::AL)
1951      .addReg(0));
1952
1953    OutStreamer.EmitInstruction(MCInstBuilder(ARM::tBX)
1954      .addReg(ScratchReg)
1955      // Predicate.
1956      .addImm(ARMCC::AL)
1957      .addReg(0));
1958    return;
1959  }
1960  }
1961
1962  MCInst TmpInst;
1963  LowerARMMachineInstrToMCInst(MI, TmpInst, *this);
1964
1965  OutStreamer.EmitInstruction(TmpInst);
1966}
1967
1968//===----------------------------------------------------------------------===//
1969// Target Registry Stuff
1970//===----------------------------------------------------------------------===//
1971
1972// Force static initialization.
1973extern "C" void LLVMInitializeARMAsmPrinter() {
1974  RegisterAsmPrinter<ARMAsmPrinter> X(TheARMTarget);
1975  RegisterAsmPrinter<ARMAsmPrinter> Y(TheThumbTarget);
1976}
1977