X86FastISel.cpp revision db4971259ce94cea26e555e9ade82672a3581f5c
1//===-- X86FastISel.cpp - X86 FastISel implementation ---------------------===//
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 defines the X86-specific support for the FastISel class. Much
11// of the target-specific code is generated by tablegen in the file
12// X86GenFastISel.inc, which is #included here.
13//
14//===----------------------------------------------------------------------===//
15
16#include "X86.h"
17#include "X86InstrBuilder.h"
18#include "X86RegisterInfo.h"
19#include "X86Subtarget.h"
20#include "X86TargetMachine.h"
21#include "llvm/CallingConv.h"
22#include "llvm/DerivedTypes.h"
23#include "llvm/GlobalVariable.h"
24#include "llvm/Instructions.h"
25#include "llvm/IntrinsicInst.h"
26#include "llvm/CodeGen/FastISel.h"
27#include "llvm/CodeGen/MachineConstantPool.h"
28#include "llvm/CodeGen/MachineFrameInfo.h"
29#include "llvm/CodeGen/MachineRegisterInfo.h"
30#include "llvm/Support/CallSite.h"
31#include "llvm/Support/ErrorHandling.h"
32#include "llvm/Support/GetElementPtrTypeIterator.h"
33#include "llvm/Target/TargetOptions.h"
34using namespace llvm;
35
36namespace {
37
38class X86FastISel : public FastISel {
39  /// Subtarget - Keep a pointer to the X86Subtarget around so that we can
40  /// make the right decision when generating code for different targets.
41  const X86Subtarget *Subtarget;
42
43  /// StackPtr - Register used as the stack pointer.
44  ///
45  unsigned StackPtr;
46
47  /// X86ScalarSSEf32, X86ScalarSSEf64 - Select between SSE or x87
48  /// floating point ops.
49  /// When SSE is available, use it for f32 operations.
50  /// When SSE2 is available, use it for f64 operations.
51  bool X86ScalarSSEf64;
52  bool X86ScalarSSEf32;
53
54public:
55  explicit X86FastISel(MachineFunction &mf,
56                       DenseMap<const Value *, unsigned> &vm,
57                       DenseMap<const BasicBlock *, MachineBasicBlock *> &bm,
58                       DenseMap<const AllocaInst *, int> &am,
59                       std::vector<std::pair<MachineInstr*, unsigned> > &pn
60#ifndef NDEBUG
61                       , SmallSet<const Instruction *, 8> &cil
62#endif
63                       )
64    : FastISel(mf, vm, bm, am, pn
65#ifndef NDEBUG
66               , cil
67#endif
68               ) {
69    Subtarget = &TM.getSubtarget<X86Subtarget>();
70    StackPtr = Subtarget->is64Bit() ? X86::RSP : X86::ESP;
71    X86ScalarSSEf64 = Subtarget->hasSSE2();
72    X86ScalarSSEf32 = Subtarget->hasSSE1();
73  }
74
75  virtual bool TargetSelectInstruction(const Instruction *I);
76
77#include "X86GenFastISel.inc"
78
79private:
80  bool X86FastEmitCompare(const Value *LHS, const Value *RHS, EVT VT);
81
82  bool X86FastEmitLoad(EVT VT, const X86AddressMode &AM, unsigned &RR);
83
84  bool X86FastEmitStore(EVT VT, const Value *Val,
85                        const X86AddressMode &AM);
86  bool X86FastEmitStore(EVT VT, unsigned Val,
87                        const X86AddressMode &AM);
88
89  bool X86FastEmitExtend(ISD::NodeType Opc, EVT DstVT, unsigned Src, EVT SrcVT,
90                         unsigned &ResultReg);
91
92  bool X86SelectAddress(const Value *V, X86AddressMode &AM);
93  bool X86SelectCallAddress(const Value *V, X86AddressMode &AM);
94
95  bool X86SelectLoad(const Instruction *I);
96
97  bool X86SelectStore(const Instruction *I);
98
99  bool X86SelectCmp(const Instruction *I);
100
101  bool X86SelectZExt(const Instruction *I);
102
103  bool X86SelectBranch(const Instruction *I);
104
105  bool X86SelectShift(const Instruction *I);
106
107  bool X86SelectSelect(const Instruction *I);
108
109  bool X86SelectTrunc(const Instruction *I);
110
111  bool X86SelectFPExt(const Instruction *I);
112  bool X86SelectFPTrunc(const Instruction *I);
113
114  bool X86SelectExtractValue(const Instruction *I);
115
116  bool X86VisitIntrinsicCall(const IntrinsicInst &I);
117  bool X86SelectCall(const Instruction *I);
118
119  CCAssignFn *CCAssignFnForCall(CallingConv::ID CC, bool isTailCall = false);
120
121  const X86InstrInfo *getInstrInfo() const {
122    return getTargetMachine()->getInstrInfo();
123  }
124  const X86TargetMachine *getTargetMachine() const {
125    return static_cast<const X86TargetMachine *>(&TM);
126  }
127
128  unsigned TargetMaterializeConstant(const Constant *C);
129
130  unsigned TargetMaterializeAlloca(const AllocaInst *C);
131
132  /// isScalarFPTypeInSSEReg - Return true if the specified scalar FP type is
133  /// computed in an SSE register, not on the X87 floating point stack.
134  bool isScalarFPTypeInSSEReg(EVT VT) const {
135    return (VT == MVT::f64 && X86ScalarSSEf64) || // f64 is when SSE2
136      (VT == MVT::f32 && X86ScalarSSEf32);   // f32 is when SSE1
137  }
138
139  bool isTypeLegal(const Type *Ty, EVT &VT, bool AllowI1 = false);
140};
141
142} // end anonymous namespace.
143
144bool X86FastISel::isTypeLegal(const Type *Ty, EVT &VT, bool AllowI1) {
145  VT = TLI.getValueType(Ty, /*HandleUnknown=*/true);
146  if (VT == MVT::Other || !VT.isSimple())
147    // Unhandled type. Halt "fast" selection and bail.
148    return false;
149
150  // For now, require SSE/SSE2 for performing floating-point operations,
151  // since x87 requires additional work.
152  if (VT == MVT::f64 && !X86ScalarSSEf64)
153     return false;
154  if (VT == MVT::f32 && !X86ScalarSSEf32)
155     return false;
156  // Similarly, no f80 support yet.
157  if (VT == MVT::f80)
158    return false;
159  // We only handle legal types. For example, on x86-32 the instruction
160  // selector contains all of the 64-bit instructions from x86-64,
161  // under the assumption that i64 won't be used if the target doesn't
162  // support it.
163  return (AllowI1 && VT == MVT::i1) || TLI.isTypeLegal(VT);
164}
165
166#include "X86GenCallingConv.inc"
167
168/// CCAssignFnForCall - Selects the correct CCAssignFn for a given calling
169/// convention.
170CCAssignFn *X86FastISel::CCAssignFnForCall(CallingConv::ID CC,
171                                           bool isTaillCall) {
172  if (Subtarget->is64Bit()) {
173    if (CC == CallingConv::GHC)
174      return CC_X86_64_GHC;
175    else if (Subtarget->isTargetWin64())
176      return CC_X86_Win64_C;
177    else
178      return CC_X86_64_C;
179  }
180
181  if (CC == CallingConv::X86_FastCall)
182    return CC_X86_32_FastCall;
183  else if (CC == CallingConv::X86_ThisCall)
184    return CC_X86_32_ThisCall;
185  else if (CC == CallingConv::Fast)
186    return CC_X86_32_FastCC;
187  else if (CC == CallingConv::GHC)
188    return CC_X86_32_GHC;
189  else
190    return CC_X86_32_C;
191}
192
193/// X86FastEmitLoad - Emit a machine instruction to load a value of type VT.
194/// The address is either pre-computed, i.e. Ptr, or a GlobalAddress, i.e. GV.
195/// Return true and the result register by reference if it is possible.
196bool X86FastISel::X86FastEmitLoad(EVT VT, const X86AddressMode &AM,
197                                  unsigned &ResultReg) {
198  // Get opcode and regclass of the output for the given load instruction.
199  unsigned Opc = 0;
200  const TargetRegisterClass *RC = NULL;
201  switch (VT.getSimpleVT().SimpleTy) {
202  default: return false;
203  case MVT::i1:
204  case MVT::i8:
205    Opc = X86::MOV8rm;
206    RC  = X86::GR8RegisterClass;
207    break;
208  case MVT::i16:
209    Opc = X86::MOV16rm;
210    RC  = X86::GR16RegisterClass;
211    break;
212  case MVT::i32:
213    Opc = X86::MOV32rm;
214    RC  = X86::GR32RegisterClass;
215    break;
216  case MVT::i64:
217    // Must be in x86-64 mode.
218    Opc = X86::MOV64rm;
219    RC  = X86::GR64RegisterClass;
220    break;
221  case MVT::f32:
222    if (Subtarget->hasSSE1()) {
223      Opc = X86::MOVSSrm;
224      RC  = X86::FR32RegisterClass;
225    } else {
226      Opc = X86::LD_Fp32m;
227      RC  = X86::RFP32RegisterClass;
228    }
229    break;
230  case MVT::f64:
231    if (Subtarget->hasSSE2()) {
232      Opc = X86::MOVSDrm;
233      RC  = X86::FR64RegisterClass;
234    } else {
235      Opc = X86::LD_Fp64m;
236      RC  = X86::RFP64RegisterClass;
237    }
238    break;
239  case MVT::f80:
240    // No f80 support yet.
241    return false;
242  }
243
244  ResultReg = createResultReg(RC);
245  addFullAddress(BuildMI(MBB, DL, TII.get(Opc), ResultReg), AM);
246  return true;
247}
248
249/// X86FastEmitStore - Emit a machine instruction to store a value Val of
250/// type VT. The address is either pre-computed, consisted of a base ptr, Ptr
251/// and a displacement offset, or a GlobalAddress,
252/// i.e. V. Return true if it is possible.
253bool
254X86FastISel::X86FastEmitStore(EVT VT, unsigned Val,
255                              const X86AddressMode &AM) {
256  // Get opcode and regclass of the output for the given store instruction.
257  unsigned Opc = 0;
258  switch (VT.getSimpleVT().SimpleTy) {
259  case MVT::f80: // No f80 support yet.
260  default: return false;
261  case MVT::i1: {
262    // Mask out all but lowest bit.
263    unsigned AndResult = createResultReg(X86::GR8RegisterClass);
264    BuildMI(MBB, DL,
265            TII.get(X86::AND8ri), AndResult).addReg(Val).addImm(1);
266    Val = AndResult;
267  }
268  // FALLTHROUGH, handling i1 as i8.
269  case MVT::i8:  Opc = X86::MOV8mr;  break;
270  case MVT::i16: Opc = X86::MOV16mr; break;
271  case MVT::i32: Opc = X86::MOV32mr; break;
272  case MVT::i64: Opc = X86::MOV64mr; break; // Must be in x86-64 mode.
273  case MVT::f32:
274    Opc = Subtarget->hasSSE1() ? X86::MOVSSmr : X86::ST_Fp32m;
275    break;
276  case MVT::f64:
277    Opc = Subtarget->hasSSE2() ? X86::MOVSDmr : X86::ST_Fp64m;
278    break;
279  }
280
281  addFullAddress(BuildMI(MBB, DL, TII.get(Opc)), AM).addReg(Val);
282  return true;
283}
284
285bool X86FastISel::X86FastEmitStore(EVT VT, const Value *Val,
286                                   const X86AddressMode &AM) {
287  // Handle 'null' like i32/i64 0.
288  if (isa<ConstantPointerNull>(Val))
289    Val = Constant::getNullValue(TD.getIntPtrType(Val->getContext()));
290
291  // If this is a store of a simple constant, fold the constant into the store.
292  if (const ConstantInt *CI = dyn_cast<ConstantInt>(Val)) {
293    unsigned Opc = 0;
294    bool Signed = true;
295    switch (VT.getSimpleVT().SimpleTy) {
296    default: break;
297    case MVT::i1:  Signed = false;     // FALLTHROUGH to handle as i8.
298    case MVT::i8:  Opc = X86::MOV8mi;  break;
299    case MVT::i16: Opc = X86::MOV16mi; break;
300    case MVT::i32: Opc = X86::MOV32mi; break;
301    case MVT::i64:
302      // Must be a 32-bit sign extended value.
303      if ((int)CI->getSExtValue() == CI->getSExtValue())
304        Opc = X86::MOV64mi32;
305      break;
306    }
307
308    if (Opc) {
309      addFullAddress(BuildMI(MBB, DL, TII.get(Opc)), AM)
310                             .addImm(Signed ? (uint64_t) CI->getSExtValue() :
311                                              CI->getZExtValue());
312      return true;
313    }
314  }
315
316  unsigned ValReg = getRegForValue(Val);
317  if (ValReg == 0)
318    return false;
319
320  return X86FastEmitStore(VT, ValReg, AM);
321}
322
323/// X86FastEmitExtend - Emit a machine instruction to extend a value Src of
324/// type SrcVT to type DstVT using the specified extension opcode Opc (e.g.
325/// ISD::SIGN_EXTEND).
326bool X86FastISel::X86FastEmitExtend(ISD::NodeType Opc, EVT DstVT,
327                                    unsigned Src, EVT SrcVT,
328                                    unsigned &ResultReg) {
329  unsigned RR = FastEmit_r(SrcVT.getSimpleVT(), DstVT.getSimpleVT(), Opc,
330                           Src, /*TODO: Kill=*/false);
331
332  if (RR != 0) {
333    ResultReg = RR;
334    return true;
335  } else
336    return false;
337}
338
339/// X86SelectAddress - Attempt to fill in an address from the given value.
340///
341bool X86FastISel::X86SelectAddress(const Value *V, X86AddressMode &AM) {
342  const User *U = NULL;
343  unsigned Opcode = Instruction::UserOp1;
344  if (const Instruction *I = dyn_cast<Instruction>(V)) {
345    // Don't walk into other basic blocks; it's possible we haven't
346    // visited them yet, so the instructions may not yet be assigned
347    // virtual registers.
348    if (MBBMap[I->getParent()] != MBB)
349      return false;
350
351    Opcode = I->getOpcode();
352    U = I;
353  } else if (const ConstantExpr *C = dyn_cast<ConstantExpr>(V)) {
354    Opcode = C->getOpcode();
355    U = C;
356  }
357
358  if (const PointerType *Ty = dyn_cast<PointerType>(V->getType()))
359    if (Ty->getAddressSpace() > 255)
360      // Fast instruction selection doesn't support the special
361      // address spaces.
362      return false;
363
364  switch (Opcode) {
365  default: break;
366  case Instruction::BitCast:
367    // Look past bitcasts.
368    return X86SelectAddress(U->getOperand(0), AM);
369
370  case Instruction::IntToPtr:
371    // Look past no-op inttoptrs.
372    if (TLI.getValueType(U->getOperand(0)->getType()) == TLI.getPointerTy())
373      return X86SelectAddress(U->getOperand(0), AM);
374    break;
375
376  case Instruction::PtrToInt:
377    // Look past no-op ptrtoints.
378    if (TLI.getValueType(U->getType()) == TLI.getPointerTy())
379      return X86SelectAddress(U->getOperand(0), AM);
380    break;
381
382  case Instruction::Alloca: {
383    // Do static allocas.
384    const AllocaInst *A = cast<AllocaInst>(V);
385    DenseMap<const AllocaInst*, int>::iterator SI = StaticAllocaMap.find(A);
386    if (SI != StaticAllocaMap.end()) {
387      AM.BaseType = X86AddressMode::FrameIndexBase;
388      AM.Base.FrameIndex = SI->second;
389      return true;
390    }
391    break;
392  }
393
394  case Instruction::Add: {
395    // Adds of constants are common and easy enough.
396    if (const ConstantInt *CI = dyn_cast<ConstantInt>(U->getOperand(1))) {
397      uint64_t Disp = (int32_t)AM.Disp + (uint64_t)CI->getSExtValue();
398      // They have to fit in the 32-bit signed displacement field though.
399      if (isInt<32>(Disp)) {
400        AM.Disp = (uint32_t)Disp;
401        return X86SelectAddress(U->getOperand(0), AM);
402      }
403    }
404    break;
405  }
406
407  case Instruction::GetElementPtr: {
408    X86AddressMode SavedAM = AM;
409
410    // Pattern-match simple GEPs.
411    uint64_t Disp = (int32_t)AM.Disp;
412    unsigned IndexReg = AM.IndexReg;
413    unsigned Scale = AM.Scale;
414    gep_type_iterator GTI = gep_type_begin(U);
415    // Iterate through the indices, folding what we can. Constants can be
416    // folded, and one dynamic index can be handled, if the scale is supported.
417    for (User::const_op_iterator i = U->op_begin() + 1, e = U->op_end();
418         i != e; ++i, ++GTI) {
419      const Value *Op = *i;
420      if (const StructType *STy = dyn_cast<StructType>(*GTI)) {
421        const StructLayout *SL = TD.getStructLayout(STy);
422        unsigned Idx = cast<ConstantInt>(Op)->getZExtValue();
423        Disp += SL->getElementOffset(Idx);
424      } else {
425        uint64_t S = TD.getTypeAllocSize(GTI.getIndexedType());
426        if (const ConstantInt *CI = dyn_cast<ConstantInt>(Op)) {
427          // Constant-offset addressing.
428          Disp += CI->getSExtValue() * S;
429        } else if (IndexReg == 0 &&
430                   (!AM.GV || !Subtarget->isPICStyleRIPRel()) &&
431                   (S == 1 || S == 2 || S == 4 || S == 8)) {
432          // Scaled-index addressing.
433          Scale = S;
434          IndexReg = getRegForGEPIndex(Op).first;
435          if (IndexReg == 0)
436            return false;
437        } else
438          // Unsupported.
439          goto unsupported_gep;
440      }
441    }
442    // Check for displacement overflow.
443    if (!isInt<32>(Disp))
444      break;
445    // Ok, the GEP indices were covered by constant-offset and scaled-index
446    // addressing. Update the address state and move on to examining the base.
447    AM.IndexReg = IndexReg;
448    AM.Scale = Scale;
449    AM.Disp = (uint32_t)Disp;
450    if (X86SelectAddress(U->getOperand(0), AM))
451      return true;
452
453    // If we couldn't merge the sub value into this addr mode, revert back to
454    // our address and just match the value instead of completely failing.
455    AM = SavedAM;
456    break;
457  unsupported_gep:
458    // Ok, the GEP indices weren't all covered.
459    break;
460  }
461  }
462
463  // Handle constant address.
464  if (const GlobalValue *GV = dyn_cast<GlobalValue>(V)) {
465    // Can't handle alternate code models yet.
466    if (TM.getCodeModel() != CodeModel::Small)
467      return false;
468
469    // RIP-relative addresses can't have additional register operands.
470    if (Subtarget->isPICStyleRIPRel() &&
471        (AM.Base.Reg != 0 || AM.IndexReg != 0))
472      return false;
473
474    // Can't handle TLS yet.
475    if (const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV))
476      if (GVar->isThreadLocal())
477        return false;
478
479    // Okay, we've committed to selecting this global. Set up the basic address.
480    AM.GV = GV;
481
482    // Allow the subtarget to classify the global.
483    unsigned char GVFlags = Subtarget->ClassifyGlobalReference(GV, TM);
484
485    // If this reference is relative to the pic base, set it now.
486    if (isGlobalRelativeToPICBase(GVFlags)) {
487      // FIXME: How do we know Base.Reg is free??
488      AM.Base.Reg = getInstrInfo()->getGlobalBaseReg(&MF);
489    }
490
491    // Unless the ABI requires an extra load, return a direct reference to
492    // the global.
493    if (!isGlobalStubReference(GVFlags)) {
494      if (Subtarget->isPICStyleRIPRel()) {
495        // Use rip-relative addressing if we can.  Above we verified that the
496        // base and index registers are unused.
497        assert(AM.Base.Reg == 0 && AM.IndexReg == 0);
498        AM.Base.Reg = X86::RIP;
499      }
500      AM.GVOpFlags = GVFlags;
501      return true;
502    }
503
504    // Ok, we need to do a load from a stub.  If we've already loaded from this
505    // stub, reuse the loaded pointer, otherwise emit the load now.
506    DenseMap<const Value*, unsigned>::iterator I = LocalValueMap.find(V);
507    unsigned LoadReg;
508    if (I != LocalValueMap.end() && I->second != 0) {
509      LoadReg = I->second;
510    } else {
511      // Issue load from stub.
512      unsigned Opc = 0;
513      const TargetRegisterClass *RC = NULL;
514      X86AddressMode StubAM;
515      StubAM.Base.Reg = AM.Base.Reg;
516      StubAM.GV = GV;
517      StubAM.GVOpFlags = GVFlags;
518
519      if (TLI.getPointerTy() == MVT::i64) {
520        Opc = X86::MOV64rm;
521        RC  = X86::GR64RegisterClass;
522
523        if (Subtarget->isPICStyleRIPRel())
524          StubAM.Base.Reg = X86::RIP;
525      } else {
526        Opc = X86::MOV32rm;
527        RC  = X86::GR32RegisterClass;
528      }
529
530      LoadReg = createResultReg(RC);
531      addFullAddress(BuildMI(MBB, DL, TII.get(Opc), LoadReg), StubAM);
532
533      // Prevent loading GV stub multiple times in same MBB.
534      LocalValueMap[V] = LoadReg;
535    }
536
537    // Now construct the final address. Note that the Disp, Scale,
538    // and Index values may already be set here.
539    AM.Base.Reg = LoadReg;
540    AM.GV = 0;
541    return true;
542  }
543
544  // If all else fails, try to materialize the value in a register.
545  if (!AM.GV || !Subtarget->isPICStyleRIPRel()) {
546    if (AM.Base.Reg == 0) {
547      AM.Base.Reg = getRegForValue(V);
548      return AM.Base.Reg != 0;
549    }
550    if (AM.IndexReg == 0) {
551      assert(AM.Scale == 1 && "Scale with no index!");
552      AM.IndexReg = getRegForValue(V);
553      return AM.IndexReg != 0;
554    }
555  }
556
557  return false;
558}
559
560/// X86SelectCallAddress - Attempt to fill in an address from the given value.
561///
562bool X86FastISel::X86SelectCallAddress(const Value *V, X86AddressMode &AM) {
563  const User *U = NULL;
564  unsigned Opcode = Instruction::UserOp1;
565  if (const Instruction *I = dyn_cast<Instruction>(V)) {
566    Opcode = I->getOpcode();
567    U = I;
568  } else if (const ConstantExpr *C = dyn_cast<ConstantExpr>(V)) {
569    Opcode = C->getOpcode();
570    U = C;
571  }
572
573  switch (Opcode) {
574  default: break;
575  case Instruction::BitCast:
576    // Look past bitcasts.
577    return X86SelectCallAddress(U->getOperand(0), AM);
578
579  case Instruction::IntToPtr:
580    // Look past no-op inttoptrs.
581    if (TLI.getValueType(U->getOperand(0)->getType()) == TLI.getPointerTy())
582      return X86SelectCallAddress(U->getOperand(0), AM);
583    break;
584
585  case Instruction::PtrToInt:
586    // Look past no-op ptrtoints.
587    if (TLI.getValueType(U->getType()) == TLI.getPointerTy())
588      return X86SelectCallAddress(U->getOperand(0), AM);
589    break;
590  }
591
592  // Handle constant address.
593  if (const GlobalValue *GV = dyn_cast<GlobalValue>(V)) {
594    // Can't handle alternate code models yet.
595    if (TM.getCodeModel() != CodeModel::Small)
596      return false;
597
598    // RIP-relative addresses can't have additional register operands.
599    if (Subtarget->isPICStyleRIPRel() &&
600        (AM.Base.Reg != 0 || AM.IndexReg != 0))
601      return false;
602
603    // Can't handle TLS or DLLImport.
604    if (const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV))
605      if (GVar->isThreadLocal() || GVar->hasDLLImportLinkage())
606        return false;
607
608    // Okay, we've committed to selecting this global. Set up the basic address.
609    AM.GV = GV;
610
611    // No ABI requires an extra load for anything other than DLLImport, which
612    // we rejected above. Return a direct reference to the global.
613    if (Subtarget->isPICStyleRIPRel()) {
614      // Use rip-relative addressing if we can.  Above we verified that the
615      // base and index registers are unused.
616      assert(AM.Base.Reg == 0 && AM.IndexReg == 0);
617      AM.Base.Reg = X86::RIP;
618    } else if (Subtarget->isPICStyleStubPIC()) {
619      AM.GVOpFlags = X86II::MO_PIC_BASE_OFFSET;
620    } else if (Subtarget->isPICStyleGOT()) {
621      AM.GVOpFlags = X86II::MO_GOTOFF;
622    }
623
624    return true;
625  }
626
627  // If all else fails, try to materialize the value in a register.
628  if (!AM.GV || !Subtarget->isPICStyleRIPRel()) {
629    if (AM.Base.Reg == 0) {
630      AM.Base.Reg = getRegForValue(V);
631      return AM.Base.Reg != 0;
632    }
633    if (AM.IndexReg == 0) {
634      assert(AM.Scale == 1 && "Scale with no index!");
635      AM.IndexReg = getRegForValue(V);
636      return AM.IndexReg != 0;
637    }
638  }
639
640  return false;
641}
642
643
644/// X86SelectStore - Select and emit code to implement store instructions.
645bool X86FastISel::X86SelectStore(const Instruction *I) {
646  EVT VT;
647  if (!isTypeLegal(I->getOperand(0)->getType(), VT, /*AllowI1=*/true))
648    return false;
649
650  X86AddressMode AM;
651  if (!X86SelectAddress(I->getOperand(1), AM))
652    return false;
653
654  return X86FastEmitStore(VT, I->getOperand(0), AM);
655}
656
657/// X86SelectLoad - Select and emit code to implement load instructions.
658///
659bool X86FastISel::X86SelectLoad(const Instruction *I)  {
660  EVT VT;
661  if (!isTypeLegal(I->getType(), VT, /*AllowI1=*/true))
662    return false;
663
664  X86AddressMode AM;
665  if (!X86SelectAddress(I->getOperand(0), AM))
666    return false;
667
668  unsigned ResultReg = 0;
669  if (X86FastEmitLoad(VT, AM, ResultReg)) {
670    UpdateValueMap(I, ResultReg);
671    return true;
672  }
673  return false;
674}
675
676static unsigned X86ChooseCmpOpcode(EVT VT) {
677  switch (VT.getSimpleVT().SimpleTy) {
678  default:       return 0;
679  case MVT::i8:  return X86::CMP8rr;
680  case MVT::i16: return X86::CMP16rr;
681  case MVT::i32: return X86::CMP32rr;
682  case MVT::i64: return X86::CMP64rr;
683  case MVT::f32: return X86::UCOMISSrr;
684  case MVT::f64: return X86::UCOMISDrr;
685  }
686}
687
688/// X86ChooseCmpImmediateOpcode - If we have a comparison with RHS as the RHS
689/// of the comparison, return an opcode that works for the compare (e.g.
690/// CMP32ri) otherwise return 0.
691static unsigned X86ChooseCmpImmediateOpcode(EVT VT, const ConstantInt *RHSC) {
692  switch (VT.getSimpleVT().SimpleTy) {
693  // Otherwise, we can't fold the immediate into this comparison.
694  default: return 0;
695  case MVT::i8: return X86::CMP8ri;
696  case MVT::i16: return X86::CMP16ri;
697  case MVT::i32: return X86::CMP32ri;
698  case MVT::i64:
699    // 64-bit comparisons are only valid if the immediate fits in a 32-bit sext
700    // field.
701    if ((int)RHSC->getSExtValue() == RHSC->getSExtValue())
702      return X86::CMP64ri32;
703    return 0;
704  }
705}
706
707bool X86FastISel::X86FastEmitCompare(const Value *Op0, const Value *Op1,
708                                     EVT VT) {
709  unsigned Op0Reg = getRegForValue(Op0);
710  if (Op0Reg == 0) return false;
711
712  // Handle 'null' like i32/i64 0.
713  if (isa<ConstantPointerNull>(Op1))
714    Op1 = Constant::getNullValue(TD.getIntPtrType(Op0->getContext()));
715
716  // We have two options: compare with register or immediate.  If the RHS of
717  // the compare is an immediate that we can fold into this compare, use
718  // CMPri, otherwise use CMPrr.
719  if (const ConstantInt *Op1C = dyn_cast<ConstantInt>(Op1)) {
720    if (unsigned CompareImmOpc = X86ChooseCmpImmediateOpcode(VT, Op1C)) {
721      BuildMI(MBB, DL, TII.get(CompareImmOpc)).addReg(Op0Reg)
722                                          .addImm(Op1C->getSExtValue());
723      return true;
724    }
725  }
726
727  unsigned CompareOpc = X86ChooseCmpOpcode(VT);
728  if (CompareOpc == 0) return false;
729
730  unsigned Op1Reg = getRegForValue(Op1);
731  if (Op1Reg == 0) return false;
732  BuildMI(MBB, DL, TII.get(CompareOpc)).addReg(Op0Reg).addReg(Op1Reg);
733
734  return true;
735}
736
737bool X86FastISel::X86SelectCmp(const Instruction *I) {
738  const CmpInst *CI = cast<CmpInst>(I);
739
740  EVT VT;
741  if (!isTypeLegal(I->getOperand(0)->getType(), VT))
742    return false;
743
744  unsigned ResultReg = createResultReg(&X86::GR8RegClass);
745  unsigned SetCCOpc;
746  bool SwapArgs;  // false -> compare Op0, Op1.  true -> compare Op1, Op0.
747  switch (CI->getPredicate()) {
748  case CmpInst::FCMP_OEQ: {
749    if (!X86FastEmitCompare(CI->getOperand(0), CI->getOperand(1), VT))
750      return false;
751
752    unsigned EReg = createResultReg(&X86::GR8RegClass);
753    unsigned NPReg = createResultReg(&X86::GR8RegClass);
754    BuildMI(MBB, DL, TII.get(X86::SETEr), EReg);
755    BuildMI(MBB, DL, TII.get(X86::SETNPr), NPReg);
756    BuildMI(MBB, DL,
757            TII.get(X86::AND8rr), ResultReg).addReg(NPReg).addReg(EReg);
758    UpdateValueMap(I, ResultReg);
759    return true;
760  }
761  case CmpInst::FCMP_UNE: {
762    if (!X86FastEmitCompare(CI->getOperand(0), CI->getOperand(1), VT))
763      return false;
764
765    unsigned NEReg = createResultReg(&X86::GR8RegClass);
766    unsigned PReg = createResultReg(&X86::GR8RegClass);
767    BuildMI(MBB, DL, TII.get(X86::SETNEr), NEReg);
768    BuildMI(MBB, DL, TII.get(X86::SETPr), PReg);
769    BuildMI(MBB, DL, TII.get(X86::OR8rr), ResultReg).addReg(PReg).addReg(NEReg);
770    UpdateValueMap(I, ResultReg);
771    return true;
772  }
773  case CmpInst::FCMP_OGT: SwapArgs = false; SetCCOpc = X86::SETAr;  break;
774  case CmpInst::FCMP_OGE: SwapArgs = false; SetCCOpc = X86::SETAEr; break;
775  case CmpInst::FCMP_OLT: SwapArgs = true;  SetCCOpc = X86::SETAr;  break;
776  case CmpInst::FCMP_OLE: SwapArgs = true;  SetCCOpc = X86::SETAEr; break;
777  case CmpInst::FCMP_ONE: SwapArgs = false; SetCCOpc = X86::SETNEr; break;
778  case CmpInst::FCMP_ORD: SwapArgs = false; SetCCOpc = X86::SETNPr; break;
779  case CmpInst::FCMP_UNO: SwapArgs = false; SetCCOpc = X86::SETPr;  break;
780  case CmpInst::FCMP_UEQ: SwapArgs = false; SetCCOpc = X86::SETEr;  break;
781  case CmpInst::FCMP_UGT: SwapArgs = true;  SetCCOpc = X86::SETBr;  break;
782  case CmpInst::FCMP_UGE: SwapArgs = true;  SetCCOpc = X86::SETBEr; break;
783  case CmpInst::FCMP_ULT: SwapArgs = false; SetCCOpc = X86::SETBr;  break;
784  case CmpInst::FCMP_ULE: SwapArgs = false; SetCCOpc = X86::SETBEr; break;
785
786  case CmpInst::ICMP_EQ:  SwapArgs = false; SetCCOpc = X86::SETEr;  break;
787  case CmpInst::ICMP_NE:  SwapArgs = false; SetCCOpc = X86::SETNEr; break;
788  case CmpInst::ICMP_UGT: SwapArgs = false; SetCCOpc = X86::SETAr;  break;
789  case CmpInst::ICMP_UGE: SwapArgs = false; SetCCOpc = X86::SETAEr; break;
790  case CmpInst::ICMP_ULT: SwapArgs = false; SetCCOpc = X86::SETBr;  break;
791  case CmpInst::ICMP_ULE: SwapArgs = false; SetCCOpc = X86::SETBEr; break;
792  case CmpInst::ICMP_SGT: SwapArgs = false; SetCCOpc = X86::SETGr;  break;
793  case CmpInst::ICMP_SGE: SwapArgs = false; SetCCOpc = X86::SETGEr; break;
794  case CmpInst::ICMP_SLT: SwapArgs = false; SetCCOpc = X86::SETLr;  break;
795  case CmpInst::ICMP_SLE: SwapArgs = false; SetCCOpc = X86::SETLEr; break;
796  default:
797    return false;
798  }
799
800  const Value *Op0 = CI->getOperand(0), *Op1 = CI->getOperand(1);
801  if (SwapArgs)
802    std::swap(Op0, Op1);
803
804  // Emit a compare of Op0/Op1.
805  if (!X86FastEmitCompare(Op0, Op1, VT))
806    return false;
807
808  BuildMI(MBB, DL, TII.get(SetCCOpc), ResultReg);
809  UpdateValueMap(I, ResultReg);
810  return true;
811}
812
813bool X86FastISel::X86SelectZExt(const Instruction *I) {
814  // Handle zero-extension from i1 to i8, which is common.
815  if (I->getType()->isIntegerTy(8) &&
816      I->getOperand(0)->getType()->isIntegerTy(1)) {
817    unsigned ResultReg = getRegForValue(I->getOperand(0));
818    if (ResultReg == 0) return false;
819    // Set the high bits to zero.
820    ResultReg = FastEmitZExtFromI1(MVT::i8, ResultReg, /*TODO: Kill=*/false);
821    if (ResultReg == 0) return false;
822    UpdateValueMap(I, ResultReg);
823    return true;
824  }
825
826  return false;
827}
828
829
830bool X86FastISel::X86SelectBranch(const Instruction *I) {
831  // Unconditional branches are selected by tablegen-generated code.
832  // Handle a conditional branch.
833  const BranchInst *BI = cast<BranchInst>(I);
834  MachineBasicBlock *TrueMBB = MBBMap[BI->getSuccessor(0)];
835  MachineBasicBlock *FalseMBB = MBBMap[BI->getSuccessor(1)];
836
837  // Fold the common case of a conditional branch with a comparison.
838  if (const CmpInst *CI = dyn_cast<CmpInst>(BI->getCondition())) {
839    if (CI->hasOneUse()) {
840      EVT VT = TLI.getValueType(CI->getOperand(0)->getType());
841
842      // Try to take advantage of fallthrough opportunities.
843      CmpInst::Predicate Predicate = CI->getPredicate();
844      if (MBB->isLayoutSuccessor(TrueMBB)) {
845        std::swap(TrueMBB, FalseMBB);
846        Predicate = CmpInst::getInversePredicate(Predicate);
847      }
848
849      bool SwapArgs;  // false -> compare Op0, Op1.  true -> compare Op1, Op0.
850      unsigned BranchOpc; // Opcode to jump on, e.g. "X86::JA"
851
852      switch (Predicate) {
853      case CmpInst::FCMP_OEQ:
854        std::swap(TrueMBB, FalseMBB);
855        Predicate = CmpInst::FCMP_UNE;
856        // FALL THROUGH
857      case CmpInst::FCMP_UNE: SwapArgs = false; BranchOpc = X86::JNE_4; break;
858      case CmpInst::FCMP_OGT: SwapArgs = false; BranchOpc = X86::JA_4;  break;
859      case CmpInst::FCMP_OGE: SwapArgs = false; BranchOpc = X86::JAE_4; break;
860      case CmpInst::FCMP_OLT: SwapArgs = true;  BranchOpc = X86::JA_4;  break;
861      case CmpInst::FCMP_OLE: SwapArgs = true;  BranchOpc = X86::JAE_4; break;
862      case CmpInst::FCMP_ONE: SwapArgs = false; BranchOpc = X86::JNE_4; break;
863      case CmpInst::FCMP_ORD: SwapArgs = false; BranchOpc = X86::JNP_4; break;
864      case CmpInst::FCMP_UNO: SwapArgs = false; BranchOpc = X86::JP_4;  break;
865      case CmpInst::FCMP_UEQ: SwapArgs = false; BranchOpc = X86::JE_4;  break;
866      case CmpInst::FCMP_UGT: SwapArgs = true;  BranchOpc = X86::JB_4;  break;
867      case CmpInst::FCMP_UGE: SwapArgs = true;  BranchOpc = X86::JBE_4; break;
868      case CmpInst::FCMP_ULT: SwapArgs = false; BranchOpc = X86::JB_4;  break;
869      case CmpInst::FCMP_ULE: SwapArgs = false; BranchOpc = X86::JBE_4; break;
870
871      case CmpInst::ICMP_EQ:  SwapArgs = false; BranchOpc = X86::JE_4;  break;
872      case CmpInst::ICMP_NE:  SwapArgs = false; BranchOpc = X86::JNE_4; break;
873      case CmpInst::ICMP_UGT: SwapArgs = false; BranchOpc = X86::JA_4;  break;
874      case CmpInst::ICMP_UGE: SwapArgs = false; BranchOpc = X86::JAE_4; break;
875      case CmpInst::ICMP_ULT: SwapArgs = false; BranchOpc = X86::JB_4;  break;
876      case CmpInst::ICMP_ULE: SwapArgs = false; BranchOpc = X86::JBE_4; break;
877      case CmpInst::ICMP_SGT: SwapArgs = false; BranchOpc = X86::JG_4;  break;
878      case CmpInst::ICMP_SGE: SwapArgs = false; BranchOpc = X86::JGE_4; break;
879      case CmpInst::ICMP_SLT: SwapArgs = false; BranchOpc = X86::JL_4;  break;
880      case CmpInst::ICMP_SLE: SwapArgs = false; BranchOpc = X86::JLE_4; break;
881      default:
882        return false;
883      }
884
885      const Value *Op0 = CI->getOperand(0), *Op1 = CI->getOperand(1);
886      if (SwapArgs)
887        std::swap(Op0, Op1);
888
889      // Emit a compare of the LHS and RHS, setting the flags.
890      if (!X86FastEmitCompare(Op0, Op1, VT))
891        return false;
892
893      BuildMI(MBB, DL, TII.get(BranchOpc)).addMBB(TrueMBB);
894
895      if (Predicate == CmpInst::FCMP_UNE) {
896        // X86 requires a second branch to handle UNE (and OEQ,
897        // which is mapped to UNE above).
898        BuildMI(MBB, DL, TII.get(X86::JP_4)).addMBB(TrueMBB);
899      }
900
901      FastEmitBranch(FalseMBB, DL);
902      MBB->addSuccessor(TrueMBB);
903      return true;
904    }
905  } else if (ExtractValueInst *EI =
906             dyn_cast<ExtractValueInst>(BI->getCondition())) {
907    // Check to see if the branch instruction is from an "arithmetic with
908    // overflow" intrinsic. The main way these intrinsics are used is:
909    //
910    //   %t = call { i32, i1 } @llvm.sadd.with.overflow.i32(i32 %v1, i32 %v2)
911    //   %sum = extractvalue { i32, i1 } %t, 0
912    //   %obit = extractvalue { i32, i1 } %t, 1
913    //   br i1 %obit, label %overflow, label %normal
914    //
915    // The %sum and %obit are converted in an ADD and a SETO/SETB before
916    // reaching the branch. Therefore, we search backwards through the MBB
917    // looking for the SETO/SETB instruction. If an instruction modifies the
918    // EFLAGS register before we reach the SETO/SETB instruction, then we can't
919    // convert the branch into a JO/JB instruction.
920    if (const IntrinsicInst *CI =
921          dyn_cast<IntrinsicInst>(EI->getAggregateOperand())){
922      if (CI->getIntrinsicID() == Intrinsic::sadd_with_overflow ||
923          CI->getIntrinsicID() == Intrinsic::uadd_with_overflow) {
924        const MachineInstr *SetMI = 0;
925        unsigned Reg = lookUpRegForValue(EI);
926
927        for (MachineBasicBlock::const_reverse_iterator
928               RI = MBB->rbegin(), RE = MBB->rend(); RI != RE; ++RI) {
929          const MachineInstr &MI = *RI;
930
931          if (MI.definesRegister(Reg)) {
932            unsigned Src, Dst, SrcSR, DstSR;
933
934            if (getInstrInfo()->isMoveInstr(MI, Src, Dst, SrcSR, DstSR)) {
935              Reg = Src;
936              continue;
937            }
938
939            SetMI = &MI;
940            break;
941          }
942
943          const TargetInstrDesc &TID = MI.getDesc();
944          if (TID.hasUnmodeledSideEffects() ||
945              TID.hasImplicitDefOfPhysReg(X86::EFLAGS))
946            break;
947        }
948
949        if (SetMI) {
950          unsigned OpCode = SetMI->getOpcode();
951
952          if (OpCode == X86::SETOr || OpCode == X86::SETBr) {
953            BuildMI(MBB, DL, TII.get(OpCode == X86::SETOr ?
954                                        X86::JO_4 : X86::JB_4))
955              .addMBB(TrueMBB);
956            FastEmitBranch(FalseMBB, DL);
957            MBB->addSuccessor(TrueMBB);
958            return true;
959          }
960        }
961      }
962    }
963  }
964
965  // Otherwise do a clumsy setcc and re-test it.
966  unsigned OpReg = getRegForValue(BI->getCondition());
967  if (OpReg == 0) return false;
968
969  BuildMI(MBB, DL, TII.get(X86::TEST8rr)).addReg(OpReg).addReg(OpReg);
970  BuildMI(MBB, DL, TII.get(X86::JNE_4)).addMBB(TrueMBB);
971  FastEmitBranch(FalseMBB, DL);
972  MBB->addSuccessor(TrueMBB);
973  return true;
974}
975
976bool X86FastISel::X86SelectShift(const Instruction *I) {
977  unsigned CReg = 0, OpReg = 0, OpImm = 0;
978  const TargetRegisterClass *RC = NULL;
979  if (I->getType()->isIntegerTy(8)) {
980    CReg = X86::CL;
981    RC = &X86::GR8RegClass;
982    switch (I->getOpcode()) {
983    case Instruction::LShr: OpReg = X86::SHR8rCL; OpImm = X86::SHR8ri; break;
984    case Instruction::AShr: OpReg = X86::SAR8rCL; OpImm = X86::SAR8ri; break;
985    case Instruction::Shl:  OpReg = X86::SHL8rCL; OpImm = X86::SHL8ri; break;
986    default: return false;
987    }
988  } else if (I->getType()->isIntegerTy(16)) {
989    CReg = X86::CX;
990    RC = &X86::GR16RegClass;
991    switch (I->getOpcode()) {
992    case Instruction::LShr: OpReg = X86::SHR16rCL; OpImm = X86::SHR16ri; break;
993    case Instruction::AShr: OpReg = X86::SAR16rCL; OpImm = X86::SAR16ri; break;
994    case Instruction::Shl:  OpReg = X86::SHL16rCL; OpImm = X86::SHL16ri; break;
995    default: return false;
996    }
997  } else if (I->getType()->isIntegerTy(32)) {
998    CReg = X86::ECX;
999    RC = &X86::GR32RegClass;
1000    switch (I->getOpcode()) {
1001    case Instruction::LShr: OpReg = X86::SHR32rCL; OpImm = X86::SHR32ri; break;
1002    case Instruction::AShr: OpReg = X86::SAR32rCL; OpImm = X86::SAR32ri; break;
1003    case Instruction::Shl:  OpReg = X86::SHL32rCL; OpImm = X86::SHL32ri; break;
1004    default: return false;
1005    }
1006  } else if (I->getType()->isIntegerTy(64)) {
1007    CReg = X86::RCX;
1008    RC = &X86::GR64RegClass;
1009    switch (I->getOpcode()) {
1010    case Instruction::LShr: OpReg = X86::SHR64rCL; OpImm = X86::SHR64ri; break;
1011    case Instruction::AShr: OpReg = X86::SAR64rCL; OpImm = X86::SAR64ri; break;
1012    case Instruction::Shl:  OpReg = X86::SHL64rCL; OpImm = X86::SHL64ri; break;
1013    default: return false;
1014    }
1015  } else {
1016    return false;
1017  }
1018
1019  EVT VT = TLI.getValueType(I->getType(), /*HandleUnknown=*/true);
1020  if (VT == MVT::Other || !isTypeLegal(I->getType(), VT))
1021    return false;
1022
1023  unsigned Op0Reg = getRegForValue(I->getOperand(0));
1024  if (Op0Reg == 0) return false;
1025
1026  // Fold immediate in shl(x,3).
1027  if (const ConstantInt *CI = dyn_cast<ConstantInt>(I->getOperand(1))) {
1028    unsigned ResultReg = createResultReg(RC);
1029    BuildMI(MBB, DL, TII.get(OpImm),
1030            ResultReg).addReg(Op0Reg).addImm(CI->getZExtValue() & 0xff);
1031    UpdateValueMap(I, ResultReg);
1032    return true;
1033  }
1034
1035  unsigned Op1Reg = getRegForValue(I->getOperand(1));
1036  if (Op1Reg == 0) return false;
1037  TII.copyRegToReg(*MBB, MBB->end(), CReg, Op1Reg, RC, RC, DL);
1038
1039  // The shift instruction uses X86::CL. If we defined a super-register
1040  // of X86::CL, emit an EXTRACT_SUBREG to precisely describe what
1041  // we're doing here.
1042  if (CReg != X86::CL)
1043    BuildMI(MBB, DL, TII.get(TargetOpcode::EXTRACT_SUBREG), X86::CL)
1044      .addReg(CReg).addImm(X86::sub_8bit);
1045
1046  unsigned ResultReg = createResultReg(RC);
1047  BuildMI(MBB, DL, TII.get(OpReg), ResultReg).addReg(Op0Reg);
1048  UpdateValueMap(I, ResultReg);
1049  return true;
1050}
1051
1052bool X86FastISel::X86SelectSelect(const Instruction *I) {
1053  EVT VT = TLI.getValueType(I->getType(), /*HandleUnknown=*/true);
1054  if (VT == MVT::Other || !isTypeLegal(I->getType(), VT))
1055    return false;
1056
1057  unsigned Opc = 0;
1058  const TargetRegisterClass *RC = NULL;
1059  if (VT.getSimpleVT() == MVT::i16) {
1060    Opc = X86::CMOVE16rr;
1061    RC = &X86::GR16RegClass;
1062  } else if (VT.getSimpleVT() == MVT::i32) {
1063    Opc = X86::CMOVE32rr;
1064    RC = &X86::GR32RegClass;
1065  } else if (VT.getSimpleVT() == MVT::i64) {
1066    Opc = X86::CMOVE64rr;
1067    RC = &X86::GR64RegClass;
1068  } else {
1069    return false;
1070  }
1071
1072  unsigned Op0Reg = getRegForValue(I->getOperand(0));
1073  if (Op0Reg == 0) return false;
1074  unsigned Op1Reg = getRegForValue(I->getOperand(1));
1075  if (Op1Reg == 0) return false;
1076  unsigned Op2Reg = getRegForValue(I->getOperand(2));
1077  if (Op2Reg == 0) return false;
1078
1079  BuildMI(MBB, DL, TII.get(X86::TEST8rr)).addReg(Op0Reg).addReg(Op0Reg);
1080  unsigned ResultReg = createResultReg(RC);
1081  BuildMI(MBB, DL, TII.get(Opc), ResultReg).addReg(Op1Reg).addReg(Op2Reg);
1082  UpdateValueMap(I, ResultReg);
1083  return true;
1084}
1085
1086bool X86FastISel::X86SelectFPExt(const Instruction *I) {
1087  // fpext from float to double.
1088  if (Subtarget->hasSSE2() &&
1089      I->getType()->isDoubleTy()) {
1090    const Value *V = I->getOperand(0);
1091    if (V->getType()->isFloatTy()) {
1092      unsigned OpReg = getRegForValue(V);
1093      if (OpReg == 0) return false;
1094      unsigned ResultReg = createResultReg(X86::FR64RegisterClass);
1095      BuildMI(MBB, DL, TII.get(X86::CVTSS2SDrr), ResultReg).addReg(OpReg);
1096      UpdateValueMap(I, ResultReg);
1097      return true;
1098    }
1099  }
1100
1101  return false;
1102}
1103
1104bool X86FastISel::X86SelectFPTrunc(const Instruction *I) {
1105  if (Subtarget->hasSSE2()) {
1106    if (I->getType()->isFloatTy()) {
1107      const Value *V = I->getOperand(0);
1108      if (V->getType()->isDoubleTy()) {
1109        unsigned OpReg = getRegForValue(V);
1110        if (OpReg == 0) return false;
1111        unsigned ResultReg = createResultReg(X86::FR32RegisterClass);
1112        BuildMI(MBB, DL, TII.get(X86::CVTSD2SSrr), ResultReg).addReg(OpReg);
1113        UpdateValueMap(I, ResultReg);
1114        return true;
1115      }
1116    }
1117  }
1118
1119  return false;
1120}
1121
1122bool X86FastISel::X86SelectTrunc(const Instruction *I) {
1123  if (Subtarget->is64Bit())
1124    // All other cases should be handled by the tblgen generated code.
1125    return false;
1126  EVT SrcVT = TLI.getValueType(I->getOperand(0)->getType());
1127  EVT DstVT = TLI.getValueType(I->getType());
1128
1129  // This code only handles truncation to byte right now.
1130  if (DstVT != MVT::i8 && DstVT != MVT::i1)
1131    // All other cases should be handled by the tblgen generated code.
1132    return false;
1133  if (SrcVT != MVT::i16 && SrcVT != MVT::i32)
1134    // All other cases should be handled by the tblgen generated code.
1135    return false;
1136
1137  unsigned InputReg = getRegForValue(I->getOperand(0));
1138  if (!InputReg)
1139    // Unhandled operand.  Halt "fast" selection and bail.
1140    return false;
1141
1142  // First issue a copy to GR16_ABCD or GR32_ABCD.
1143  unsigned CopyOpc = (SrcVT == MVT::i16) ? X86::MOV16rr : X86::MOV32rr;
1144  const TargetRegisterClass *CopyRC = (SrcVT == MVT::i16)
1145    ? X86::GR16_ABCDRegisterClass : X86::GR32_ABCDRegisterClass;
1146  unsigned CopyReg = createResultReg(CopyRC);
1147  BuildMI(MBB, DL, TII.get(CopyOpc), CopyReg).addReg(InputReg);
1148
1149  // Then issue an extract_subreg.
1150  unsigned ResultReg = FastEmitInst_extractsubreg(MVT::i8,
1151                                                  CopyReg, /*Kill=*/true,
1152                                                  X86::sub_8bit);
1153  if (!ResultReg)
1154    return false;
1155
1156  UpdateValueMap(I, ResultReg);
1157  return true;
1158}
1159
1160bool X86FastISel::X86SelectExtractValue(const Instruction *I) {
1161  const ExtractValueInst *EI = cast<ExtractValueInst>(I);
1162  const Value *Agg = EI->getAggregateOperand();
1163
1164  if (const IntrinsicInst *CI = dyn_cast<IntrinsicInst>(Agg)) {
1165    switch (CI->getIntrinsicID()) {
1166    default: break;
1167    case Intrinsic::sadd_with_overflow:
1168    case Intrinsic::uadd_with_overflow:
1169      // Cheat a little. We know that the registers for "add" and "seto" are
1170      // allocated sequentially. However, we only keep track of the register
1171      // for "add" in the value map. Use extractvalue's index to get the
1172      // correct register for "seto".
1173      UpdateValueMap(I, lookUpRegForValue(Agg) + *EI->idx_begin());
1174      return true;
1175    }
1176  }
1177
1178  return false;
1179}
1180
1181bool X86FastISel::X86VisitIntrinsicCall(const IntrinsicInst &I) {
1182  // FIXME: Handle more intrinsics.
1183  switch (I.getIntrinsicID()) {
1184  default: return false;
1185  case Intrinsic::stackprotector: {
1186    // Emit code inline code to store the stack guard onto the stack.
1187    EVT PtrTy = TLI.getPointerTy();
1188
1189    const Value *Op1 = I.getOperand(1); // The guard's value.
1190    const AllocaInst *Slot = cast<AllocaInst>(I.getOperand(2));
1191
1192    // Grab the frame index.
1193    X86AddressMode AM;
1194    if (!X86SelectAddress(Slot, AM)) return false;
1195
1196    if (!X86FastEmitStore(PtrTy, Op1, AM)) return false;
1197
1198    return true;
1199  }
1200  case Intrinsic::objectsize: {
1201    ConstantInt *CI = dyn_cast<ConstantInt>(I.getOperand(2));
1202    const Type *Ty = I.getCalledFunction()->getReturnType();
1203
1204    assert(CI && "Non-constant type in Intrinsic::objectsize?");
1205
1206    EVT VT;
1207    if (!isTypeLegal(Ty, VT))
1208      return false;
1209
1210    unsigned OpC = 0;
1211    if (VT == MVT::i32)
1212      OpC = X86::MOV32ri;
1213    else if (VT == MVT::i64)
1214      OpC = X86::MOV64ri;
1215    else
1216      return false;
1217
1218    unsigned ResultReg = createResultReg(TLI.getRegClassFor(VT));
1219    BuildMI(MBB, DL, TII.get(OpC), ResultReg).
1220                                  addImm(CI->isZero() ? -1ULL : 0);
1221    UpdateValueMap(&I, ResultReg);
1222    return true;
1223  }
1224  case Intrinsic::dbg_declare: {
1225    const DbgDeclareInst *DI = cast<DbgDeclareInst>(&I);
1226    X86AddressMode AM;
1227    assert(DI->getAddress() && "Null address should be checked earlier!");
1228    if (!X86SelectAddress(DI->getAddress(), AM))
1229      return false;
1230    const TargetInstrDesc &II = TII.get(TargetOpcode::DBG_VALUE);
1231    // FIXME may need to add RegState::Debug to any registers produced,
1232    // although ESP/EBP should be the only ones at the moment.
1233    addFullAddress(BuildMI(MBB, DL, II), AM).addImm(0).
1234                                        addMetadata(DI->getVariable());
1235    return true;
1236  }
1237  case Intrinsic::trap: {
1238    BuildMI(MBB, DL, TII.get(X86::TRAP));
1239    return true;
1240  }
1241  case Intrinsic::sadd_with_overflow:
1242  case Intrinsic::uadd_with_overflow: {
1243    // Replace "add with overflow" intrinsics with an "add" instruction followed
1244    // by a seto/setc instruction. Later on, when the "extractvalue"
1245    // instructions are encountered, we use the fact that two registers were
1246    // created sequentially to get the correct registers for the "sum" and the
1247    // "overflow bit".
1248    const Function *Callee = I.getCalledFunction();
1249    const Type *RetTy =
1250      cast<StructType>(Callee->getReturnType())->getTypeAtIndex(unsigned(0));
1251
1252    EVT VT;
1253    if (!isTypeLegal(RetTy, VT))
1254      return false;
1255
1256    const Value *Op1 = I.getOperand(1);
1257    const Value *Op2 = I.getOperand(2);
1258    unsigned Reg1 = getRegForValue(Op1);
1259    unsigned Reg2 = getRegForValue(Op2);
1260
1261    if (Reg1 == 0 || Reg2 == 0)
1262      // FIXME: Handle values *not* in registers.
1263      return false;
1264
1265    unsigned OpC = 0;
1266    if (VT == MVT::i32)
1267      OpC = X86::ADD32rr;
1268    else if (VT == MVT::i64)
1269      OpC = X86::ADD64rr;
1270    else
1271      return false;
1272
1273    unsigned ResultReg = createResultReg(TLI.getRegClassFor(VT));
1274    BuildMI(MBB, DL, TII.get(OpC), ResultReg).addReg(Reg1).addReg(Reg2);
1275    unsigned DestReg1 = UpdateValueMap(&I, ResultReg);
1276
1277    // If the add with overflow is an intra-block value then we just want to
1278    // create temporaries for it like normal.  If it is a cross-block value then
1279    // UpdateValueMap will return the cross-block register used.  Since we
1280    // *really* want the value to be live in the register pair known by
1281    // UpdateValueMap, we have to use DestReg1+1 as the destination register in
1282    // the cross block case.  In the non-cross-block case, we should just make
1283    // another register for the value.
1284    if (DestReg1 != ResultReg)
1285      ResultReg = DestReg1+1;
1286    else
1287      ResultReg = createResultReg(TLI.getRegClassFor(MVT::i8));
1288
1289    unsigned Opc = X86::SETBr;
1290    if (I.getIntrinsicID() == Intrinsic::sadd_with_overflow)
1291      Opc = X86::SETOr;
1292    BuildMI(MBB, DL, TII.get(Opc), ResultReg);
1293    return true;
1294  }
1295  }
1296}
1297
1298bool X86FastISel::X86SelectCall(const Instruction *I) {
1299  const CallInst *CI = cast<CallInst>(I);
1300  const Value *Callee = I->getOperand(0);
1301
1302  // Can't handle inline asm yet.
1303  if (isa<InlineAsm>(Callee))
1304    return false;
1305
1306  // Handle intrinsic calls.
1307  if (const IntrinsicInst *II = dyn_cast<IntrinsicInst>(CI))
1308    return X86VisitIntrinsicCall(*II);
1309
1310  // Handle only C and fastcc calling conventions for now.
1311  ImmutableCallSite CS(CI);
1312  CallingConv::ID CC = CS.getCallingConv();
1313  if (CC != CallingConv::C &&
1314      CC != CallingConv::Fast &&
1315      CC != CallingConv::X86_FastCall)
1316    return false;
1317
1318  // fastcc with -tailcallopt is intended to provide a guaranteed
1319  // tail call optimization. Fastisel doesn't know how to do that.
1320  if (CC == CallingConv::Fast && GuaranteedTailCallOpt)
1321    return false;
1322
1323  // Let SDISel handle vararg functions.
1324  const PointerType *PT = cast<PointerType>(CS.getCalledValue()->getType());
1325  const FunctionType *FTy = cast<FunctionType>(PT->getElementType());
1326  if (FTy->isVarArg())
1327    return false;
1328
1329  // Fast-isel doesn't know about callee-pop yet.
1330  if (Subtarget->IsCalleePop(FTy->isVarArg(), CC))
1331    return false;
1332
1333  // Handle *simple* calls for now.
1334  const Type *RetTy = CS.getType();
1335  EVT RetVT;
1336  if (RetTy->isVoidTy())
1337    RetVT = MVT::isVoid;
1338  else if (!isTypeLegal(RetTy, RetVT, true))
1339    return false;
1340
1341  // Materialize callee address in a register. FIXME: GV address can be
1342  // handled with a CALLpcrel32 instead.
1343  X86AddressMode CalleeAM;
1344  if (!X86SelectCallAddress(Callee, CalleeAM))
1345    return false;
1346  unsigned CalleeOp = 0;
1347  const GlobalValue *GV = 0;
1348  if (CalleeAM.GV != 0) {
1349    GV = CalleeAM.GV;
1350  } else if (CalleeAM.Base.Reg != 0) {
1351    CalleeOp = CalleeAM.Base.Reg;
1352  } else
1353    return false;
1354
1355  // Allow calls which produce i1 results.
1356  bool AndToI1 = false;
1357  if (RetVT == MVT::i1) {
1358    RetVT = MVT::i8;
1359    AndToI1 = true;
1360  }
1361
1362  // Deal with call operands first.
1363  SmallVector<const Value *, 8> ArgVals;
1364  SmallVector<unsigned, 8> Args;
1365  SmallVector<EVT, 8> ArgVTs;
1366  SmallVector<ISD::ArgFlagsTy, 8> ArgFlags;
1367  Args.reserve(CS.arg_size());
1368  ArgVals.reserve(CS.arg_size());
1369  ArgVTs.reserve(CS.arg_size());
1370  ArgFlags.reserve(CS.arg_size());
1371  for (ImmutableCallSite::arg_iterator i = CS.arg_begin(), e = CS.arg_end();
1372       i != e; ++i) {
1373    unsigned Arg = getRegForValue(*i);
1374    if (Arg == 0)
1375      return false;
1376    ISD::ArgFlagsTy Flags;
1377    unsigned AttrInd = i - CS.arg_begin() + 1;
1378    if (CS.paramHasAttr(AttrInd, Attribute::SExt))
1379      Flags.setSExt();
1380    if (CS.paramHasAttr(AttrInd, Attribute::ZExt))
1381      Flags.setZExt();
1382
1383    // FIXME: Only handle *easy* calls for now.
1384    if (CS.paramHasAttr(AttrInd, Attribute::InReg) ||
1385        CS.paramHasAttr(AttrInd, Attribute::StructRet) ||
1386        CS.paramHasAttr(AttrInd, Attribute::Nest) ||
1387        CS.paramHasAttr(AttrInd, Attribute::ByVal))
1388      return false;
1389
1390    const Type *ArgTy = (*i)->getType();
1391    EVT ArgVT;
1392    if (!isTypeLegal(ArgTy, ArgVT))
1393      return false;
1394    unsigned OriginalAlignment = TD.getABITypeAlignment(ArgTy);
1395    Flags.setOrigAlign(OriginalAlignment);
1396
1397    Args.push_back(Arg);
1398    ArgVals.push_back(*i);
1399    ArgVTs.push_back(ArgVT);
1400    ArgFlags.push_back(Flags);
1401  }
1402
1403  // Analyze operands of the call, assigning locations to each operand.
1404  SmallVector<CCValAssign, 16> ArgLocs;
1405  CCState CCInfo(CC, false, TM, ArgLocs, I->getParent()->getContext());
1406
1407  // Allocate shadow area for Win64
1408  if (Subtarget->isTargetWin64()) {
1409    CCInfo.AllocateStack(32, 8);
1410  }
1411
1412  CCInfo.AnalyzeCallOperands(ArgVTs, ArgFlags, CCAssignFnForCall(CC));
1413
1414  // Get a count of how many bytes are to be pushed on the stack.
1415  unsigned NumBytes = CCInfo.getNextStackOffset();
1416
1417  // Issue CALLSEQ_START
1418  unsigned AdjStackDown = TM.getRegisterInfo()->getCallFrameSetupOpcode();
1419  BuildMI(MBB, DL, TII.get(AdjStackDown)).addImm(NumBytes);
1420
1421  // Process argument: walk the register/memloc assignments, inserting
1422  // copies / loads.
1423  SmallVector<unsigned, 4> RegArgs;
1424  for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) {
1425    CCValAssign &VA = ArgLocs[i];
1426    unsigned Arg = Args[VA.getValNo()];
1427    EVT ArgVT = ArgVTs[VA.getValNo()];
1428
1429    // Promote the value if needed.
1430    switch (VA.getLocInfo()) {
1431    default: llvm_unreachable("Unknown loc info!");
1432    case CCValAssign::Full: break;
1433    case CCValAssign::SExt: {
1434      bool Emitted = X86FastEmitExtend(ISD::SIGN_EXTEND, VA.getLocVT(),
1435                                       Arg, ArgVT, Arg);
1436      assert(Emitted && "Failed to emit a sext!"); Emitted=Emitted;
1437      Emitted = true;
1438      ArgVT = VA.getLocVT();
1439      break;
1440    }
1441    case CCValAssign::ZExt: {
1442      bool Emitted = X86FastEmitExtend(ISD::ZERO_EXTEND, VA.getLocVT(),
1443                                       Arg, ArgVT, Arg);
1444      assert(Emitted && "Failed to emit a zext!"); Emitted=Emitted;
1445      Emitted = true;
1446      ArgVT = VA.getLocVT();
1447      break;
1448    }
1449    case CCValAssign::AExt: {
1450      bool Emitted = X86FastEmitExtend(ISD::ANY_EXTEND, VA.getLocVT(),
1451                                       Arg, ArgVT, Arg);
1452      if (!Emitted)
1453        Emitted = X86FastEmitExtend(ISD::ZERO_EXTEND, VA.getLocVT(),
1454                                    Arg, ArgVT, Arg);
1455      if (!Emitted)
1456        Emitted = X86FastEmitExtend(ISD::SIGN_EXTEND, VA.getLocVT(),
1457                                    Arg, ArgVT, Arg);
1458
1459      assert(Emitted && "Failed to emit a aext!"); Emitted=Emitted;
1460      ArgVT = VA.getLocVT();
1461      break;
1462    }
1463    case CCValAssign::BCvt: {
1464      unsigned BC = FastEmit_r(ArgVT.getSimpleVT(), VA.getLocVT().getSimpleVT(),
1465                               ISD::BIT_CONVERT, Arg, /*TODO: Kill=*/false);
1466      assert(BC != 0 && "Failed to emit a bitcast!");
1467      Arg = BC;
1468      ArgVT = VA.getLocVT();
1469      break;
1470    }
1471    }
1472
1473    if (VA.isRegLoc()) {
1474      TargetRegisterClass* RC = TLI.getRegClassFor(ArgVT);
1475      bool Emitted = TII.copyRegToReg(*MBB, MBB->end(), VA.getLocReg(),
1476                                      Arg, RC, RC, DL);
1477      assert(Emitted && "Failed to emit a copy instruction!"); Emitted=Emitted;
1478      Emitted = true;
1479      RegArgs.push_back(VA.getLocReg());
1480    } else {
1481      unsigned LocMemOffset = VA.getLocMemOffset();
1482      X86AddressMode AM;
1483      AM.Base.Reg = StackPtr;
1484      AM.Disp = LocMemOffset;
1485      const Value *ArgVal = ArgVals[VA.getValNo()];
1486
1487      // If this is a really simple value, emit this with the Value* version of
1488      // X86FastEmitStore.  If it isn't simple, we don't want to do this, as it
1489      // can cause us to reevaluate the argument.
1490      if (isa<ConstantInt>(ArgVal) || isa<ConstantPointerNull>(ArgVal))
1491        X86FastEmitStore(ArgVT, ArgVal, AM);
1492      else
1493        X86FastEmitStore(ArgVT, Arg, AM);
1494    }
1495  }
1496
1497  // ELF / PIC requires GOT in the EBX register before function calls via PLT
1498  // GOT pointer.
1499  if (Subtarget->isPICStyleGOT()) {
1500    TargetRegisterClass *RC = X86::GR32RegisterClass;
1501    unsigned Base = getInstrInfo()->getGlobalBaseReg(&MF);
1502    bool Emitted = TII.copyRegToReg(*MBB, MBB->end(), X86::EBX, Base, RC, RC,
1503                                    DL);
1504    assert(Emitted && "Failed to emit a copy instruction!"); Emitted=Emitted;
1505    Emitted = true;
1506  }
1507
1508  // Issue the call.
1509  MachineInstrBuilder MIB;
1510  if (CalleeOp) {
1511    // Register-indirect call.
1512    unsigned CallOpc = Subtarget->is64Bit() ? X86::CALL64r : X86::CALL32r;
1513    MIB = BuildMI(MBB, DL, TII.get(CallOpc)).addReg(CalleeOp);
1514
1515  } else {
1516    // Direct call.
1517    assert(GV && "Not a direct call");
1518    unsigned CallOpc =
1519      Subtarget->is64Bit() ? X86::CALL64pcrel32 : X86::CALLpcrel32;
1520
1521    // See if we need any target-specific flags on the GV operand.
1522    unsigned char OpFlags = 0;
1523
1524    // On ELF targets, in both X86-64 and X86-32 mode, direct calls to
1525    // external symbols most go through the PLT in PIC mode.  If the symbol
1526    // has hidden or protected visibility, or if it is static or local, then
1527    // we don't need to use the PLT - we can directly call it.
1528    if (Subtarget->isTargetELF() &&
1529        TM.getRelocationModel() == Reloc::PIC_ &&
1530        GV->hasDefaultVisibility() && !GV->hasLocalLinkage()) {
1531      OpFlags = X86II::MO_PLT;
1532    } else if (Subtarget->isPICStyleStubAny() &&
1533               (GV->isDeclaration() || GV->isWeakForLinker()) &&
1534               Subtarget->getDarwinVers() < 9) {
1535      // PC-relative references to external symbols should go through $stub,
1536      // unless we're building with the leopard linker or later, which
1537      // automatically synthesizes these stubs.
1538      OpFlags = X86II::MO_DARWIN_STUB;
1539    }
1540
1541
1542    MIB = BuildMI(MBB, DL, TII.get(CallOpc)).addGlobalAddress(GV, 0, OpFlags);
1543  }
1544
1545  // Add an implicit use GOT pointer in EBX.
1546  if (Subtarget->isPICStyleGOT())
1547    MIB.addReg(X86::EBX);
1548
1549  // Add implicit physical register uses to the call.
1550  for (unsigned i = 0, e = RegArgs.size(); i != e; ++i)
1551    MIB.addReg(RegArgs[i]);
1552
1553  // Issue CALLSEQ_END
1554  unsigned AdjStackUp = TM.getRegisterInfo()->getCallFrameDestroyOpcode();
1555  BuildMI(MBB, DL, TII.get(AdjStackUp)).addImm(NumBytes).addImm(0);
1556
1557  // Now handle call return value (if any).
1558  SmallVector<unsigned, 4> UsedRegs;
1559  if (RetVT.getSimpleVT().SimpleTy != MVT::isVoid) {
1560    SmallVector<CCValAssign, 16> RVLocs;
1561    CCState CCInfo(CC, false, TM, RVLocs, I->getParent()->getContext());
1562    CCInfo.AnalyzeCallResult(RetVT, RetCC_X86);
1563
1564    // Copy all of the result registers out of their specified physreg.
1565    assert(RVLocs.size() == 1 && "Can't handle multi-value calls!");
1566    EVT CopyVT = RVLocs[0].getValVT();
1567    TargetRegisterClass* DstRC = TLI.getRegClassFor(CopyVT);
1568    TargetRegisterClass *SrcRC = DstRC;
1569
1570    // If this is a call to a function that returns an fp value on the x87 fp
1571    // stack, but where we prefer to use the value in xmm registers, copy it
1572    // out as F80 and use a truncate to move it from fp stack reg to xmm reg.
1573    if ((RVLocs[0].getLocReg() == X86::ST0 ||
1574         RVLocs[0].getLocReg() == X86::ST1) &&
1575        isScalarFPTypeInSSEReg(RVLocs[0].getValVT())) {
1576      CopyVT = MVT::f80;
1577      SrcRC = X86::RSTRegisterClass;
1578      DstRC = X86::RFP80RegisterClass;
1579    }
1580
1581    unsigned ResultReg = createResultReg(DstRC);
1582    bool Emitted = TII.copyRegToReg(*MBB, MBB->end(), ResultReg,
1583                                    RVLocs[0].getLocReg(), DstRC, SrcRC, DL);
1584    assert(Emitted && "Failed to emit a copy instruction!"); Emitted=Emitted;
1585    Emitted = true;
1586    UsedRegs.push_back(RVLocs[0].getLocReg());
1587
1588    if (CopyVT != RVLocs[0].getValVT()) {
1589      // Round the F80 the right size, which also moves to the appropriate xmm
1590      // register. This is accomplished by storing the F80 value in memory and
1591      // then loading it back. Ewww...
1592      EVT ResVT = RVLocs[0].getValVT();
1593      unsigned Opc = ResVT == MVT::f32 ? X86::ST_Fp80m32 : X86::ST_Fp80m64;
1594      unsigned MemSize = ResVT.getSizeInBits()/8;
1595      int FI = MFI.CreateStackObject(MemSize, MemSize, false);
1596      addFrameReference(BuildMI(MBB, DL, TII.get(Opc)), FI).addReg(ResultReg);
1597      DstRC = ResVT == MVT::f32
1598        ? X86::FR32RegisterClass : X86::FR64RegisterClass;
1599      Opc = ResVT == MVT::f32 ? X86::MOVSSrm : X86::MOVSDrm;
1600      ResultReg = createResultReg(DstRC);
1601      addFrameReference(BuildMI(MBB, DL, TII.get(Opc), ResultReg), FI);
1602    }
1603
1604    if (AndToI1) {
1605      // Mask out all but lowest bit for some call which produces an i1.
1606      unsigned AndResult = createResultReg(X86::GR8RegisterClass);
1607      BuildMI(MBB, DL,
1608              TII.get(X86::AND8ri), AndResult).addReg(ResultReg).addImm(1);
1609      ResultReg = AndResult;
1610    }
1611
1612    UpdateValueMap(I, ResultReg);
1613  }
1614
1615  // Set all unused physreg defs as dead.
1616  static_cast<MachineInstr *>(MIB)->setPhysRegsDeadExcept(UsedRegs, TRI);
1617
1618  return true;
1619}
1620
1621
1622bool
1623X86FastISel::TargetSelectInstruction(const Instruction *I)  {
1624  switch (I->getOpcode()) {
1625  default: break;
1626  case Instruction::Load:
1627    return X86SelectLoad(I);
1628  case Instruction::Store:
1629    return X86SelectStore(I);
1630  case Instruction::ICmp:
1631  case Instruction::FCmp:
1632    return X86SelectCmp(I);
1633  case Instruction::ZExt:
1634    return X86SelectZExt(I);
1635  case Instruction::Br:
1636    return X86SelectBranch(I);
1637  case Instruction::Call:
1638    return X86SelectCall(I);
1639  case Instruction::LShr:
1640  case Instruction::AShr:
1641  case Instruction::Shl:
1642    return X86SelectShift(I);
1643  case Instruction::Select:
1644    return X86SelectSelect(I);
1645  case Instruction::Trunc:
1646    return X86SelectTrunc(I);
1647  case Instruction::FPExt:
1648    return X86SelectFPExt(I);
1649  case Instruction::FPTrunc:
1650    return X86SelectFPTrunc(I);
1651  case Instruction::ExtractValue:
1652    return X86SelectExtractValue(I);
1653  case Instruction::IntToPtr: // Deliberate fall-through.
1654  case Instruction::PtrToInt: {
1655    EVT SrcVT = TLI.getValueType(I->getOperand(0)->getType());
1656    EVT DstVT = TLI.getValueType(I->getType());
1657    if (DstVT.bitsGT(SrcVT))
1658      return X86SelectZExt(I);
1659    if (DstVT.bitsLT(SrcVT))
1660      return X86SelectTrunc(I);
1661    unsigned Reg = getRegForValue(I->getOperand(0));
1662    if (Reg == 0) return false;
1663    UpdateValueMap(I, Reg);
1664    return true;
1665  }
1666  }
1667
1668  return false;
1669}
1670
1671unsigned X86FastISel::TargetMaterializeConstant(const Constant *C) {
1672  EVT VT;
1673  if (!isTypeLegal(C->getType(), VT))
1674    return false;
1675
1676  // Get opcode and regclass of the output for the given load instruction.
1677  unsigned Opc = 0;
1678  const TargetRegisterClass *RC = NULL;
1679  switch (VT.getSimpleVT().SimpleTy) {
1680  default: return false;
1681  case MVT::i8:
1682    Opc = X86::MOV8rm;
1683    RC  = X86::GR8RegisterClass;
1684    break;
1685  case MVT::i16:
1686    Opc = X86::MOV16rm;
1687    RC  = X86::GR16RegisterClass;
1688    break;
1689  case MVT::i32:
1690    Opc = X86::MOV32rm;
1691    RC  = X86::GR32RegisterClass;
1692    break;
1693  case MVT::i64:
1694    // Must be in x86-64 mode.
1695    Opc = X86::MOV64rm;
1696    RC  = X86::GR64RegisterClass;
1697    break;
1698  case MVT::f32:
1699    if (Subtarget->hasSSE1()) {
1700      Opc = X86::MOVSSrm;
1701      RC  = X86::FR32RegisterClass;
1702    } else {
1703      Opc = X86::LD_Fp32m;
1704      RC  = X86::RFP32RegisterClass;
1705    }
1706    break;
1707  case MVT::f64:
1708    if (Subtarget->hasSSE2()) {
1709      Opc = X86::MOVSDrm;
1710      RC  = X86::FR64RegisterClass;
1711    } else {
1712      Opc = X86::LD_Fp64m;
1713      RC  = X86::RFP64RegisterClass;
1714    }
1715    break;
1716  case MVT::f80:
1717    // No f80 support yet.
1718    return false;
1719  }
1720
1721  // Materialize addresses with LEA instructions.
1722  if (isa<GlobalValue>(C)) {
1723    X86AddressMode AM;
1724    if (X86SelectAddress(C, AM)) {
1725      if (TLI.getPointerTy() == MVT::i32)
1726        Opc = X86::LEA32r;
1727      else
1728        Opc = X86::LEA64r;
1729      unsigned ResultReg = createResultReg(RC);
1730      addLeaAddress(BuildMI(MBB, DL, TII.get(Opc), ResultReg), AM);
1731      return ResultReg;
1732    }
1733    return 0;
1734  }
1735
1736  // MachineConstantPool wants an explicit alignment.
1737  unsigned Align = TD.getPrefTypeAlignment(C->getType());
1738  if (Align == 0) {
1739    // Alignment of vector types.  FIXME!
1740    Align = TD.getTypeAllocSize(C->getType());
1741  }
1742
1743  // x86-32 PIC requires a PIC base register for constant pools.
1744  unsigned PICBase = 0;
1745  unsigned char OpFlag = 0;
1746  if (Subtarget->isPICStyleStubPIC()) { // Not dynamic-no-pic
1747    OpFlag = X86II::MO_PIC_BASE_OFFSET;
1748    PICBase = getInstrInfo()->getGlobalBaseReg(&MF);
1749  } else if (Subtarget->isPICStyleGOT()) {
1750    OpFlag = X86II::MO_GOTOFF;
1751    PICBase = getInstrInfo()->getGlobalBaseReg(&MF);
1752  } else if (Subtarget->isPICStyleRIPRel() &&
1753             TM.getCodeModel() == CodeModel::Small) {
1754    PICBase = X86::RIP;
1755  }
1756
1757  // Create the load from the constant pool.
1758  unsigned MCPOffset = MCP.getConstantPoolIndex(C, Align);
1759  unsigned ResultReg = createResultReg(RC);
1760  addConstantPoolReference(BuildMI(MBB, DL, TII.get(Opc), ResultReg),
1761                           MCPOffset, PICBase, OpFlag);
1762
1763  return ResultReg;
1764}
1765
1766unsigned X86FastISel::TargetMaterializeAlloca(const AllocaInst *C) {
1767  // Fail on dynamic allocas. At this point, getRegForValue has already
1768  // checked its CSE maps, so if we're here trying to handle a dynamic
1769  // alloca, we're not going to succeed. X86SelectAddress has a
1770  // check for dynamic allocas, because it's called directly from
1771  // various places, but TargetMaterializeAlloca also needs a check
1772  // in order to avoid recursion between getRegForValue,
1773  // X86SelectAddrss, and TargetMaterializeAlloca.
1774  if (!StaticAllocaMap.count(C))
1775    return 0;
1776
1777  X86AddressMode AM;
1778  if (!X86SelectAddress(C, AM))
1779    return 0;
1780  unsigned Opc = Subtarget->is64Bit() ? X86::LEA64r : X86::LEA32r;
1781  TargetRegisterClass* RC = TLI.getRegClassFor(TLI.getPointerTy());
1782  unsigned ResultReg = createResultReg(RC);
1783  addLeaAddress(BuildMI(MBB, DL, TII.get(Opc), ResultReg), AM);
1784  return ResultReg;
1785}
1786
1787namespace llvm {
1788  llvm::FastISel *X86::createFastISel(MachineFunction &mf,
1789                        DenseMap<const Value *, unsigned> &vm,
1790                        DenseMap<const BasicBlock *, MachineBasicBlock *> &bm,
1791                        DenseMap<const AllocaInst *, int> &am,
1792                        std::vector<std::pair<MachineInstr*, unsigned> > &pn
1793#ifndef NDEBUG
1794                        , SmallSet<const Instruction *, 8> &cil
1795#endif
1796                        ) {
1797    return new X86FastISel(mf, vm, bm, am, pn
1798#ifndef NDEBUG
1799                           , cil
1800#endif
1801                           );
1802  }
1803}
1804