X86ISelLowering.h revision 198090
1//===-- X86ISelLowering.h - X86 DAG Lowering Interface ----------*- C++ -*-===//
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 interfaces that X86 uses to lower LLVM code into a
11// selection DAG.
12//
13//===----------------------------------------------------------------------===//
14
15#ifndef X86ISELLOWERING_H
16#define X86ISELLOWERING_H
17
18#include "X86Subtarget.h"
19#include "X86RegisterInfo.h"
20#include "X86MachineFunctionInfo.h"
21#include "llvm/Target/TargetLowering.h"
22#include "llvm/CodeGen/FastISel.h"
23#include "llvm/CodeGen/SelectionDAG.h"
24#include "llvm/CodeGen/CallingConvLower.h"
25
26namespace llvm {
27  namespace X86ISD {
28    // X86 Specific DAG Nodes
29    enum NodeType {
30      // Start the numbering where the builtin ops leave off.
31      FIRST_NUMBER = ISD::BUILTIN_OP_END,
32
33      /// BSF - Bit scan forward.
34      /// BSR - Bit scan reverse.
35      BSF,
36      BSR,
37
38      /// SHLD, SHRD - Double shift instructions. These correspond to
39      /// X86::SHLDxx and X86::SHRDxx instructions.
40      SHLD,
41      SHRD,
42
43      /// FAND - Bitwise logical AND of floating point values. This corresponds
44      /// to X86::ANDPS or X86::ANDPD.
45      FAND,
46
47      /// FOR - Bitwise logical OR of floating point values. This corresponds
48      /// to X86::ORPS or X86::ORPD.
49      FOR,
50
51      /// FXOR - Bitwise logical XOR of floating point values. This corresponds
52      /// to X86::XORPS or X86::XORPD.
53      FXOR,
54
55      /// FSRL - Bitwise logical right shift of floating point values. These
56      /// corresponds to X86::PSRLDQ.
57      FSRL,
58
59      /// FILD, FILD_FLAG - This instruction implements SINT_TO_FP with the
60      /// integer source in memory and FP reg result.  This corresponds to the
61      /// X86::FILD*m instructions. It has three inputs (token chain, address,
62      /// and source type) and two outputs (FP value and token chain). FILD_FLAG
63      /// also produces a flag).
64      FILD,
65      FILD_FLAG,
66
67      /// FP_TO_INT*_IN_MEM - This instruction implements FP_TO_SINT with the
68      /// integer destination in memory and a FP reg source.  This corresponds
69      /// to the X86::FIST*m instructions and the rounding mode change stuff. It
70      /// has two inputs (token chain and address) and two outputs (int value
71      /// and token chain).
72      FP_TO_INT16_IN_MEM,
73      FP_TO_INT32_IN_MEM,
74      FP_TO_INT64_IN_MEM,
75
76      /// FLD - This instruction implements an extending load to FP stack slots.
77      /// This corresponds to the X86::FLD32m / X86::FLD64m. It takes a chain
78      /// operand, ptr to load from, and a ValueType node indicating the type
79      /// to load to.
80      FLD,
81
82      /// FST - This instruction implements a truncating store to FP stack
83      /// slots. This corresponds to the X86::FST32m / X86::FST64m. It takes a
84      /// chain operand, value to store, address, and a ValueType to store it
85      /// as.
86      FST,
87
88      /// CALL - These operations represent an abstract X86 call
89      /// instruction, which includes a bunch of information.  In particular the
90      /// operands of these node are:
91      ///
92      ///     #0 - The incoming token chain
93      ///     #1 - The callee
94      ///     #2 - The number of arg bytes the caller pushes on the stack.
95      ///     #3 - The number of arg bytes the callee pops off the stack.
96      ///     #4 - The value to pass in AL/AX/EAX (optional)
97      ///     #5 - The value to pass in DL/DX/EDX (optional)
98      ///
99      /// The result values of these nodes are:
100      ///
101      ///     #0 - The outgoing token chain
102      ///     #1 - The first register result value (optional)
103      ///     #2 - The second register result value (optional)
104      ///
105      CALL,
106
107      /// RDTSC_DAG - This operation implements the lowering for
108      /// readcyclecounter
109      RDTSC_DAG,
110
111      /// X86 compare and logical compare instructions.
112      CMP, COMI, UCOMI,
113
114      /// X86 bit-test instructions.
115      BT,
116
117      /// X86 SetCC. Operand 0 is condition code, and operand 1 is the flag
118      /// operand produced by a CMP instruction.
119      SETCC,
120
121      /// X86 conditional moves. Operand 0 and operand 1 are the two values
122      /// to select from. Operand 2 is the condition code, and operand 3 is the
123      /// flag operand produced by a CMP or TEST instruction. It also writes a
124      /// flag result.
125      CMOV,
126
127      /// X86 conditional branches. Operand 0 is the chain operand, operand 1
128      /// is the block to branch if condition is true, operand 2 is the
129      /// condition code, and operand 3 is the flag operand produced by a CMP
130      /// or TEST instruction.
131      BRCOND,
132
133      /// Return with a flag operand. Operand 0 is the chain operand, operand
134      /// 1 is the number of bytes of stack to pop.
135      RET_FLAG,
136
137      /// REP_STOS - Repeat fill, corresponds to X86::REP_STOSx.
138      REP_STOS,
139
140      /// REP_MOVS - Repeat move, corresponds to X86::REP_MOVSx.
141      REP_MOVS,
142
143      /// GlobalBaseReg - On Darwin, this node represents the result of the popl
144      /// at function entry, used for PIC code.
145      GlobalBaseReg,
146
147      /// Wrapper - A wrapper node for TargetConstantPool,
148      /// TargetExternalSymbol, and TargetGlobalAddress.
149      Wrapper,
150
151      /// WrapperRIP - Special wrapper used under X86-64 PIC mode for RIP
152      /// relative displacements.
153      WrapperRIP,
154
155      /// PEXTRB - Extract an 8-bit value from a vector and zero extend it to
156      /// i32, corresponds to X86::PEXTRB.
157      PEXTRB,
158
159      /// PEXTRW - Extract a 16-bit value from a vector and zero extend it to
160      /// i32, corresponds to X86::PEXTRW.
161      PEXTRW,
162
163      /// INSERTPS - Insert any element of a 4 x float vector into any element
164      /// of a destination 4 x floatvector.
165      INSERTPS,
166
167      /// PINSRB - Insert the lower 8-bits of a 32-bit value to a vector,
168      /// corresponds to X86::PINSRB.
169      PINSRB,
170
171      /// PINSRW - Insert the lower 16-bits of a 32-bit value to a vector,
172      /// corresponds to X86::PINSRW.
173      PINSRW,
174
175      /// PSHUFB - Shuffle 16 8-bit values within a vector.
176      PSHUFB,
177
178      /// FMAX, FMIN - Floating point max and min.
179      ///
180      FMAX, FMIN,
181
182      /// FRSQRT, FRCP - Floating point reciprocal-sqrt and reciprocal
183      /// approximation.  Note that these typically require refinement
184      /// in order to obtain suitable precision.
185      FRSQRT, FRCP,
186
187      // TLSADDR - Thread Local Storage.
188      TLSADDR,
189
190      // SegmentBaseAddress - The address segment:0
191      SegmentBaseAddress,
192
193      // EH_RETURN - Exception Handling helpers.
194      EH_RETURN,
195
196      /// TC_RETURN - Tail call return.
197      ///   operand #0 chain
198      ///   operand #1 callee (register or absolute)
199      ///   operand #2 stack adjustment
200      ///   operand #3 optional in flag
201      TC_RETURN,
202
203      // LCMPXCHG_DAG, LCMPXCHG8_DAG - Compare and swap.
204      LCMPXCHG_DAG,
205      LCMPXCHG8_DAG,
206
207      // FNSTCW16m - Store FP control world into i16 memory.
208      FNSTCW16m,
209
210      // VZEXT_MOVL - Vector move low and zero extend.
211      VZEXT_MOVL,
212
213      // VZEXT_LOAD - Load, scalar_to_vector, and zero extend.
214      VZEXT_LOAD,
215
216      // VSHL, VSRL - Vector logical left / right shift.
217      VSHL, VSRL,
218
219      // CMPPD, CMPPS - Vector double/float comparison.
220      // CMPPD, CMPPS - Vector double/float comparison.
221      CMPPD, CMPPS,
222
223      // PCMP* - Vector integer comparisons.
224      PCMPEQB, PCMPEQW, PCMPEQD, PCMPEQQ,
225      PCMPGTB, PCMPGTW, PCMPGTD, PCMPGTQ,
226
227      // ADD, SUB, SMUL, UMUL, etc. - Arithmetic operations with FLAGS results.
228      ADD, SUB, SMUL, UMUL,
229      INC, DEC, OR, XOR, AND,
230
231      // MUL_IMM - X86 specific multiply by immediate.
232      MUL_IMM,
233
234      // PTEST - Vector bitwise comparisons
235      PTEST,
236
237      // VASTART_SAVE_XMM_REGS - Save xmm argument registers to the stack,
238      // according to %al. An operator is needed so that this can be expanded
239      // with control flow.
240      VASTART_SAVE_XMM_REGS,
241
242      // ATOMADD64_DAG, ATOMSUB64_DAG, ATOMOR64_DAG, ATOMAND64_DAG,
243      // ATOMXOR64_DAG, ATOMNAND64_DAG, ATOMSWAP64_DAG -
244      // Atomic 64-bit binary operations.
245      ATOMADD64_DAG = ISD::FIRST_TARGET_MEMORY_OPCODE,
246      ATOMSUB64_DAG,
247      ATOMOR64_DAG,
248      ATOMXOR64_DAG,
249      ATOMAND64_DAG,
250      ATOMNAND64_DAG,
251      ATOMSWAP64_DAG
252    };
253  }
254
255  /// Define some predicates that are used for node matching.
256  namespace X86 {
257    /// isPSHUFDMask - Return true if the specified VECTOR_SHUFFLE operand
258    /// specifies a shuffle of elements that is suitable for input to PSHUFD.
259    bool isPSHUFDMask(ShuffleVectorSDNode *N);
260
261    /// isPSHUFHWMask - Return true if the specified VECTOR_SHUFFLE operand
262    /// specifies a shuffle of elements that is suitable for input to PSHUFD.
263    bool isPSHUFHWMask(ShuffleVectorSDNode *N);
264
265    /// isPSHUFLWMask - Return true if the specified VECTOR_SHUFFLE operand
266    /// specifies a shuffle of elements that is suitable for input to PSHUFD.
267    bool isPSHUFLWMask(ShuffleVectorSDNode *N);
268
269    /// isSHUFPMask - Return true if the specified VECTOR_SHUFFLE operand
270    /// specifies a shuffle of elements that is suitable for input to SHUFP*.
271    bool isSHUFPMask(ShuffleVectorSDNode *N);
272
273    /// isMOVHLPSMask - Return true if the specified VECTOR_SHUFFLE operand
274    /// specifies a shuffle of elements that is suitable for input to MOVHLPS.
275    bool isMOVHLPSMask(ShuffleVectorSDNode *N);
276
277    /// isMOVHLPS_v_undef_Mask - Special case of isMOVHLPSMask for canonical form
278    /// of vector_shuffle v, v, <2, 3, 2, 3>, i.e. vector_shuffle v, undef,
279    /// <2, 3, 2, 3>
280    bool isMOVHLPS_v_undef_Mask(ShuffleVectorSDNode *N);
281
282    /// isMOVLPMask - Return true if the specified VECTOR_SHUFFLE operand
283    /// specifies a shuffle of elements that is suitable for MOVLP{S|D}.
284    bool isMOVLPMask(ShuffleVectorSDNode *N);
285
286    /// isMOVHPMask - Return true if the specified VECTOR_SHUFFLE operand
287    /// specifies a shuffle of elements that is suitable for MOVHP{S|D}.
288    /// as well as MOVLHPS.
289    bool isMOVHPMask(ShuffleVectorSDNode *N);
290
291    /// isUNPCKLMask - Return true if the specified VECTOR_SHUFFLE operand
292    /// specifies a shuffle of elements that is suitable for input to UNPCKL.
293    bool isUNPCKLMask(ShuffleVectorSDNode *N, bool V2IsSplat = false);
294
295    /// isUNPCKHMask - Return true if the specified VECTOR_SHUFFLE operand
296    /// specifies a shuffle of elements that is suitable for input to UNPCKH.
297    bool isUNPCKHMask(ShuffleVectorSDNode *N, bool V2IsSplat = false);
298
299    /// isUNPCKL_v_undef_Mask - Special case of isUNPCKLMask for canonical form
300    /// of vector_shuffle v, v, <0, 4, 1, 5>, i.e. vector_shuffle v, undef,
301    /// <0, 0, 1, 1>
302    bool isUNPCKL_v_undef_Mask(ShuffleVectorSDNode *N);
303
304    /// isUNPCKH_v_undef_Mask - Special case of isUNPCKHMask for canonical form
305    /// of vector_shuffle v, v, <2, 6, 3, 7>, i.e. vector_shuffle v, undef,
306    /// <2, 2, 3, 3>
307    bool isUNPCKH_v_undef_Mask(ShuffleVectorSDNode *N);
308
309    /// isMOVLMask - Return true if the specified VECTOR_SHUFFLE operand
310    /// specifies a shuffle of elements that is suitable for input to MOVSS,
311    /// MOVSD, and MOVD, i.e. setting the lowest element.
312    bool isMOVLMask(ShuffleVectorSDNode *N);
313
314    /// isMOVSHDUPMask - Return true if the specified VECTOR_SHUFFLE operand
315    /// specifies a shuffle of elements that is suitable for input to MOVSHDUP.
316    bool isMOVSHDUPMask(ShuffleVectorSDNode *N);
317
318    /// isMOVSLDUPMask - Return true if the specified VECTOR_SHUFFLE operand
319    /// specifies a shuffle of elements that is suitable for input to MOVSLDUP.
320    bool isMOVSLDUPMask(ShuffleVectorSDNode *N);
321
322    /// isMOVDDUPMask - Return true if the specified VECTOR_SHUFFLE operand
323    /// specifies a shuffle of elements that is suitable for input to MOVDDUP.
324    bool isMOVDDUPMask(ShuffleVectorSDNode *N);
325
326    /// getShuffleSHUFImmediate - Return the appropriate immediate to shuffle
327    /// the specified isShuffleMask VECTOR_SHUFFLE mask with PSHUF* and SHUFP*
328    /// instructions.
329    unsigned getShuffleSHUFImmediate(SDNode *N);
330
331    /// getShufflePSHUFHWImmediate - Return the appropriate immediate to shuffle
332    /// the specified isShuffleMask VECTOR_SHUFFLE mask with PSHUFHW
333    /// instructions.
334    unsigned getShufflePSHUFHWImmediate(SDNode *N);
335
336    /// getShufflePSHUFKWImmediate - Return the appropriate immediate to shuffle
337    /// the specified isShuffleMask VECTOR_SHUFFLE mask with PSHUFLW
338    /// instructions.
339    unsigned getShufflePSHUFLWImmediate(SDNode *N);
340
341    /// isZeroNode - Returns true if Elt is a constant zero or a floating point
342    /// constant +0.0.
343    bool isZeroNode(SDValue Elt);
344
345    /// isOffsetSuitableForCodeModel - Returns true of the given offset can be
346    /// fit into displacement field of the instruction.
347    bool isOffsetSuitableForCodeModel(int64_t Offset, CodeModel::Model M,
348                                      bool hasSymbolicDisplacement = true);
349  }
350
351  //===--------------------------------------------------------------------===//
352  //  X86TargetLowering - X86 Implementation of the TargetLowering interface
353  class X86TargetLowering : public TargetLowering {
354    int VarArgsFrameIndex;            // FrameIndex for start of varargs area.
355    int RegSaveFrameIndex;            // X86-64 vararg func register save area.
356    unsigned VarArgsGPOffset;         // X86-64 vararg func int reg offset.
357    unsigned VarArgsFPOffset;         // X86-64 vararg func fp reg offset.
358    int BytesToPopOnReturn;           // Number of arg bytes ret should pop.
359    int BytesCallerReserves;          // Number of arg bytes caller makes.
360
361  public:
362    explicit X86TargetLowering(X86TargetMachine &TM);
363
364    /// getPICJumpTableRelocaBase - Returns relocation base for the given PIC
365    /// jumptable.
366    SDValue getPICJumpTableRelocBase(SDValue Table,
367                                       SelectionDAG &DAG) const;
368
369    // Return the number of bytes that a function should pop when it returns (in
370    // addition to the space used by the return address).
371    //
372    unsigned getBytesToPopOnReturn() const { return BytesToPopOnReturn; }
373
374    // Return the number of bytes that the caller reserves for arguments passed
375    // to this function.
376    unsigned getBytesCallerReserves() const { return BytesCallerReserves; }
377
378    /// getStackPtrReg - Return the stack pointer register we are using: either
379    /// ESP or RSP.
380    unsigned getStackPtrReg() const { return X86StackPtr; }
381
382    /// getByValTypeAlignment - Return the desired alignment for ByVal aggregate
383    /// function arguments in the caller parameter area. For X86, aggregates
384    /// that contains are placed at 16-byte boundaries while the rest are at
385    /// 4-byte boundaries.
386    virtual unsigned getByValTypeAlignment(const Type *Ty) const;
387
388    /// getOptimalMemOpType - Returns the target specific optimal type for load
389    /// and store operations as a result of memset, memcpy, and memmove
390    /// lowering. It returns EVT::iAny if SelectionDAG should be responsible for
391    /// determining it.
392    virtual EVT getOptimalMemOpType(uint64_t Size, unsigned Align,
393                                    bool isSrcConst, bool isSrcStr,
394                                    SelectionDAG &DAG) const;
395
396    /// allowsUnalignedMemoryAccesses - Returns true if the target allows
397    /// unaligned memory accesses. of the specified type.
398    virtual bool allowsUnalignedMemoryAccesses(EVT VT) const {
399      return true;
400    }
401
402    /// LowerOperation - Provide custom lowering hooks for some operations.
403    ///
404    virtual SDValue LowerOperation(SDValue Op, SelectionDAG &DAG);
405
406    /// ReplaceNodeResults - Replace the results of node with an illegal result
407    /// type with new values built out of custom code.
408    ///
409    virtual void ReplaceNodeResults(SDNode *N, SmallVectorImpl<SDValue>&Results,
410                                    SelectionDAG &DAG);
411
412
413    virtual SDValue PerformDAGCombine(SDNode *N, DAGCombinerInfo &DCI) const;
414
415    virtual MachineBasicBlock *EmitInstrWithCustomInserter(MachineInstr *MI,
416                                                         MachineBasicBlock *MBB,
417                    DenseMap<MachineBasicBlock*, MachineBasicBlock*> *EM) const;
418
419
420    /// getTargetNodeName - This method returns the name of a target specific
421    /// DAG node.
422    virtual const char *getTargetNodeName(unsigned Opcode) const;
423
424    /// getSetCCResultType - Return the ISD::SETCC ValueType
425    virtual MVT::SimpleValueType getSetCCResultType(EVT VT) const;
426
427    /// computeMaskedBitsForTargetNode - Determine which of the bits specified
428    /// in Mask are known to be either zero or one and return them in the
429    /// KnownZero/KnownOne bitsets.
430    virtual void computeMaskedBitsForTargetNode(const SDValue Op,
431                                                const APInt &Mask,
432                                                APInt &KnownZero,
433                                                APInt &KnownOne,
434                                                const SelectionDAG &DAG,
435                                                unsigned Depth = 0) const;
436
437    virtual bool
438    isGAPlusOffset(SDNode *N, GlobalValue* &GA, int64_t &Offset) const;
439
440    SDValue getReturnAddressFrameIndex(SelectionDAG &DAG);
441
442    virtual bool ExpandInlineAsm(CallInst *CI) const;
443
444    ConstraintType getConstraintType(const std::string &Constraint) const;
445
446    std::vector<unsigned>
447      getRegClassForInlineAsmConstraint(const std::string &Constraint,
448                                        EVT VT) const;
449
450    virtual const char *LowerXConstraint(EVT ConstraintVT) const;
451
452    /// LowerAsmOperandForConstraint - Lower the specified operand into the Ops
453    /// vector.  If it is invalid, don't add anything to Ops. If hasMemory is
454    /// true it means one of the asm constraint of the inline asm instruction
455    /// being processed is 'm'.
456    virtual void LowerAsmOperandForConstraint(SDValue Op,
457                                              char ConstraintLetter,
458                                              bool hasMemory,
459                                              std::vector<SDValue> &Ops,
460                                              SelectionDAG &DAG) const;
461
462    /// getRegForInlineAsmConstraint - Given a physical register constraint
463    /// (e.g. {edx}), return the register number and the register class for the
464    /// register.  This should only be used for C_Register constraints.  On
465    /// error, this returns a register number of 0.
466    std::pair<unsigned, const TargetRegisterClass*>
467      getRegForInlineAsmConstraint(const std::string &Constraint,
468                                   EVT VT) const;
469
470    /// isLegalAddressingMode - Return true if the addressing mode represented
471    /// by AM is legal for this target, for a load/store of the specified type.
472    virtual bool isLegalAddressingMode(const AddrMode &AM, const Type *Ty)const;
473
474    /// isTruncateFree - Return true if it's free to truncate a value of
475    /// type Ty1 to type Ty2. e.g. On x86 it's free to truncate a i32 value in
476    /// register EAX to i16 by referencing its sub-register AX.
477    virtual bool isTruncateFree(const Type *Ty1, const Type *Ty2) const;
478    virtual bool isTruncateFree(EVT VT1, EVT VT2) const;
479
480    /// isZExtFree - Return true if any actual instruction that defines a
481    /// value of type Ty1 implicit zero-extends the value to Ty2 in the result
482    /// register. This does not necessarily include registers defined in
483    /// unknown ways, such as incoming arguments, or copies from unknown
484    /// virtual registers. Also, if isTruncateFree(Ty2, Ty1) is true, this
485    /// does not necessarily apply to truncate instructions. e.g. on x86-64,
486    /// all instructions that define 32-bit values implicit zero-extend the
487    /// result out to 64 bits.
488    virtual bool isZExtFree(const Type *Ty1, const Type *Ty2) const;
489    virtual bool isZExtFree(EVT VT1, EVT VT2) const;
490
491    /// isNarrowingProfitable - Return true if it's profitable to narrow
492    /// operations of type VT1 to VT2. e.g. on x86, it's profitable to narrow
493    /// from i32 to i8 but not from i32 to i16.
494    virtual bool isNarrowingProfitable(EVT VT1, EVT VT2) const;
495
496    /// isShuffleMaskLegal - Targets can use this to indicate that they only
497    /// support *some* VECTOR_SHUFFLE operations, those with specific masks.
498    /// By default, if a target supports the VECTOR_SHUFFLE node, all mask
499    /// values are assumed to be legal.
500    virtual bool isShuffleMaskLegal(const SmallVectorImpl<int> &Mask,
501                                    EVT VT) const;
502
503    /// isVectorClearMaskLegal - Similar to isShuffleMaskLegal. This is
504    /// used by Targets can use this to indicate if there is a suitable
505    /// VECTOR_SHUFFLE that can be used to replace a VAND with a constant
506    /// pool entry.
507    virtual bool isVectorClearMaskLegal(const SmallVectorImpl<int> &Mask,
508                                        EVT VT) const;
509
510    /// ShouldShrinkFPConstant - If true, then instruction selection should
511    /// seek to shrink the FP constant of the specified type to a smaller type
512    /// in order to save space and / or reduce runtime.
513    virtual bool ShouldShrinkFPConstant(EVT VT) const {
514      // Don't shrink FP constpool if SSE2 is available since cvtss2sd is more
515      // expensive than a straight movsd. On the other hand, it's important to
516      // shrink long double fp constant since fldt is very slow.
517      return !X86ScalarSSEf64 || VT == MVT::f80;
518    }
519
520    /// IsEligibleForTailCallOptimization - Check whether the call is eligible
521    /// for tail call optimization. Targets which want to do tail call
522    /// optimization should implement this function.
523    virtual bool
524    IsEligibleForTailCallOptimization(SDValue Callee,
525                                      CallingConv::ID CalleeCC,
526                                      bool isVarArg,
527                                      const SmallVectorImpl<ISD::InputArg> &Ins,
528                                      SelectionDAG& DAG) const;
529
530    virtual const X86Subtarget* getSubtarget() {
531      return Subtarget;
532    }
533
534    /// isScalarFPTypeInSSEReg - Return true if the specified scalar FP type is
535    /// computed in an SSE register, not on the X87 floating point stack.
536    bool isScalarFPTypeInSSEReg(EVT VT) const {
537      return (VT == MVT::f64 && X86ScalarSSEf64) || // f64 is when SSE2
538      (VT == MVT::f32 && X86ScalarSSEf32);   // f32 is when SSE1
539    }
540
541    /// getWidenVectorType: given a vector type, returns the type to widen
542    /// to (e.g., v7i8 to v8i8). If the vector type is legal, it returns itself.
543    /// If there is no vector type that we want to widen to, returns EVT::Other
544    /// When and were to widen is target dependent based on the cost of
545    /// scalarizing vs using the wider vector type.
546    virtual EVT getWidenVectorType(EVT VT) const;
547
548    /// createFastISel - This method returns a target specific FastISel object,
549    /// or null if the target does not support "fast" ISel.
550    virtual FastISel *
551    createFastISel(MachineFunction &mf,
552                   MachineModuleInfo *mmi, DwarfWriter *dw,
553                   DenseMap<const Value *, unsigned> &,
554                   DenseMap<const BasicBlock *, MachineBasicBlock *> &,
555                   DenseMap<const AllocaInst *, int> &
556#ifndef NDEBUG
557                   , SmallSet<Instruction*, 8> &
558#endif
559                   );
560
561    /// getFunctionAlignment - Return the Log2 alignment of this function.
562    virtual unsigned getFunctionAlignment(const Function *F) const;
563
564  private:
565    /// Subtarget - Keep a pointer to the X86Subtarget around so that we can
566    /// make the right decision when generating code for different targets.
567    const X86Subtarget *Subtarget;
568    const X86RegisterInfo *RegInfo;
569    const TargetData *TD;
570
571    /// X86StackPtr - X86 physical register used as stack ptr.
572    unsigned X86StackPtr;
573
574    /// X86ScalarSSEf32, X86ScalarSSEf64 - Select between SSE or x87
575    /// floating point ops.
576    /// When SSE is available, use it for f32 operations.
577    /// When SSE2 is available, use it for f64 operations.
578    bool X86ScalarSSEf32;
579    bool X86ScalarSSEf64;
580
581    SDValue LowerCallResult(SDValue Chain, SDValue InFlag,
582                            CallingConv::ID CallConv, bool isVarArg,
583                            const SmallVectorImpl<ISD::InputArg> &Ins,
584                            DebugLoc dl, SelectionDAG &DAG,
585                            SmallVectorImpl<SDValue> &InVals);
586    SDValue LowerMemArgument(SDValue Chain,
587                             CallingConv::ID CallConv,
588                             const SmallVectorImpl<ISD::InputArg> &ArgInfo,
589                             DebugLoc dl, SelectionDAG &DAG,
590                             const CCValAssign &VA,  MachineFrameInfo *MFI,
591                              unsigned i);
592    SDValue LowerMemOpCallTo(SDValue Chain, SDValue StackPtr, SDValue Arg,
593                             DebugLoc dl, SelectionDAG &DAG,
594                             const CCValAssign &VA,
595                             ISD::ArgFlagsTy Flags);
596
597    // Call lowering helpers.
598    bool IsCalleePop(bool isVarArg, CallingConv::ID CallConv);
599    SDValue EmitTailCallLoadRetAddr(SelectionDAG &DAG, SDValue &OutRetAddr,
600                                SDValue Chain, bool IsTailCall, bool Is64Bit,
601                                int FPDiff, DebugLoc dl);
602
603    CCAssignFn *CCAssignFnForNode(CallingConv::ID CallConv) const;
604    NameDecorationStyle NameDecorationForCallConv(CallingConv::ID CallConv);
605    unsigned GetAlignedArgumentStackSize(unsigned StackSize, SelectionDAG &DAG);
606
607    std::pair<SDValue,SDValue> FP_TO_INTHelper(SDValue Op, SelectionDAG &DAG,
608                                               bool isSigned);
609
610    SDValue LowerBUILD_VECTOR(SDValue Op, SelectionDAG &DAG);
611    SDValue LowerVECTOR_SHUFFLE(SDValue Op, SelectionDAG &DAG);
612    SDValue LowerEXTRACT_VECTOR_ELT(SDValue Op, SelectionDAG &DAG);
613    SDValue LowerEXTRACT_VECTOR_ELT_SSE4(SDValue Op, SelectionDAG &DAG);
614    SDValue LowerINSERT_VECTOR_ELT(SDValue Op, SelectionDAG &DAG);
615    SDValue LowerINSERT_VECTOR_ELT_SSE4(SDValue Op, SelectionDAG &DAG);
616    SDValue LowerSCALAR_TO_VECTOR(SDValue Op, SelectionDAG &DAG);
617    SDValue LowerConstantPool(SDValue Op, SelectionDAG &DAG);
618    SDValue LowerGlobalAddress(const GlobalValue *GV, DebugLoc dl,
619                               int64_t Offset, SelectionDAG &DAG) const;
620    SDValue LowerGlobalAddress(SDValue Op, SelectionDAG &DAG);
621    SDValue LowerGlobalTLSAddress(SDValue Op, SelectionDAG &DAG);
622    SDValue LowerExternalSymbol(SDValue Op, SelectionDAG &DAG);
623    SDValue LowerShift(SDValue Op, SelectionDAG &DAG);
624    SDValue BuildFILD(SDValue Op, EVT SrcVT, SDValue Chain, SDValue StackSlot,
625                      SelectionDAG &DAG);
626    SDValue LowerSINT_TO_FP(SDValue Op, SelectionDAG &DAG);
627    SDValue LowerUINT_TO_FP(SDValue Op, SelectionDAG &DAG);
628    SDValue LowerUINT_TO_FP_i64(SDValue Op, SelectionDAG &DAG);
629    SDValue LowerUINT_TO_FP_i32(SDValue Op, SelectionDAG &DAG);
630    SDValue LowerFP_TO_SINT(SDValue Op, SelectionDAG &DAG);
631    SDValue LowerFP_TO_UINT(SDValue Op, SelectionDAG &DAG);
632    SDValue LowerFABS(SDValue Op, SelectionDAG &DAG);
633    SDValue LowerFNEG(SDValue Op, SelectionDAG &DAG);
634    SDValue LowerFCOPYSIGN(SDValue Op, SelectionDAG &DAG);
635    SDValue LowerSETCC(SDValue Op, SelectionDAG &DAG);
636    SDValue LowerVSETCC(SDValue Op, SelectionDAG &DAG);
637    SDValue LowerSELECT(SDValue Op, SelectionDAG &DAG);
638    SDValue LowerBRCOND(SDValue Op, SelectionDAG &DAG);
639    SDValue LowerMEMSET(SDValue Op, SelectionDAG &DAG);
640    SDValue LowerJumpTable(SDValue Op, SelectionDAG &DAG);
641    SDValue LowerDYNAMIC_STACKALLOC(SDValue Op, SelectionDAG &DAG);
642    SDValue LowerVASTART(SDValue Op, SelectionDAG &DAG);
643    SDValue LowerVAARG(SDValue Op, SelectionDAG &DAG);
644    SDValue LowerVACOPY(SDValue Op, SelectionDAG &DAG);
645    SDValue LowerINTRINSIC_WO_CHAIN(SDValue Op, SelectionDAG &DAG);
646    SDValue LowerRETURNADDR(SDValue Op, SelectionDAG &DAG);
647    SDValue LowerFRAMEADDR(SDValue Op, SelectionDAG &DAG);
648    SDValue LowerFRAME_TO_ARGS_OFFSET(SDValue Op, SelectionDAG &DAG);
649    SDValue LowerEH_RETURN(SDValue Op, SelectionDAG &DAG);
650    SDValue LowerTRAMPOLINE(SDValue Op, SelectionDAG &DAG);
651    SDValue LowerFLT_ROUNDS_(SDValue Op, SelectionDAG &DAG);
652    SDValue LowerCTLZ(SDValue Op, SelectionDAG &DAG);
653    SDValue LowerCTTZ(SDValue Op, SelectionDAG &DAG);
654    SDValue LowerMUL_V2I64(SDValue Op, SelectionDAG &DAG);
655    SDValue LowerXALUO(SDValue Op, SelectionDAG &DAG);
656
657    SDValue LowerCMP_SWAP(SDValue Op, SelectionDAG &DAG);
658    SDValue LowerLOAD_SUB(SDValue Op, SelectionDAG &DAG);
659    SDValue LowerREADCYCLECOUNTER(SDValue Op, SelectionDAG &DAG);
660
661    virtual SDValue
662      LowerFormalArguments(SDValue Chain,
663                           CallingConv::ID CallConv, bool isVarArg,
664                           const SmallVectorImpl<ISD::InputArg> &Ins,
665                           DebugLoc dl, SelectionDAG &DAG,
666                           SmallVectorImpl<SDValue> &InVals);
667    virtual SDValue
668      LowerCall(SDValue Chain, SDValue Callee,
669                CallingConv::ID CallConv, bool isVarArg, bool isTailCall,
670                const SmallVectorImpl<ISD::OutputArg> &Outs,
671                const SmallVectorImpl<ISD::InputArg> &Ins,
672                DebugLoc dl, SelectionDAG &DAG,
673                SmallVectorImpl<SDValue> &InVals);
674
675    virtual SDValue
676      LowerReturn(SDValue Chain,
677                  CallingConv::ID CallConv, bool isVarArg,
678                  const SmallVectorImpl<ISD::OutputArg> &Outs,
679                  DebugLoc dl, SelectionDAG &DAG);
680
681    void ReplaceATOMIC_BINARY_64(SDNode *N, SmallVectorImpl<SDValue> &Results,
682                                 SelectionDAG &DAG, unsigned NewOp);
683
684    SDValue EmitTargetCodeForMemset(SelectionDAG &DAG, DebugLoc dl,
685                                    SDValue Chain,
686                                    SDValue Dst, SDValue Src,
687                                    SDValue Size, unsigned Align,
688                                    const Value *DstSV, uint64_t DstSVOff);
689    SDValue EmitTargetCodeForMemcpy(SelectionDAG &DAG, DebugLoc dl,
690                                    SDValue Chain,
691                                    SDValue Dst, SDValue Src,
692                                    SDValue Size, unsigned Align,
693                                    bool AlwaysInline,
694                                    const Value *DstSV, uint64_t DstSVOff,
695                                    const Value *SrcSV, uint64_t SrcSVOff);
696
697    /// Utility function to emit string processing sse4.2 instructions
698    /// that return in xmm0.
699    /// This takes the instruction to expand, the associated machine basic
700    /// block, the number of args, and whether or not the second arg is
701    /// in memory or not.
702    MachineBasicBlock *EmitPCMP(MachineInstr *BInstr, MachineBasicBlock *BB,
703				unsigned argNum, bool inMem) const;
704
705    /// Utility function to emit atomic bitwise operations (and, or, xor).
706    /// It takes the bitwise instruction to expand, the associated machine basic
707    /// block, and the associated X86 opcodes for reg/reg and reg/imm.
708    MachineBasicBlock *EmitAtomicBitwiseWithCustomInserter(
709                                                    MachineInstr *BInstr,
710                                                    MachineBasicBlock *BB,
711                                                    unsigned regOpc,
712                                                    unsigned immOpc,
713                                                    unsigned loadOpc,
714                                                    unsigned cxchgOpc,
715                                                    unsigned copyOpc,
716                                                    unsigned notOpc,
717                                                    unsigned EAXreg,
718                                                    TargetRegisterClass *RC,
719                                                    bool invSrc = false) const;
720
721    MachineBasicBlock *EmitAtomicBit6432WithCustomInserter(
722                                                    MachineInstr *BInstr,
723                                                    MachineBasicBlock *BB,
724                                                    unsigned regOpcL,
725                                                    unsigned regOpcH,
726                                                    unsigned immOpcL,
727                                                    unsigned immOpcH,
728                                                    bool invSrc = false) const;
729
730    /// Utility function to emit atomic min and max.  It takes the min/max
731    /// instruction to expand, the associated basic block, and the associated
732    /// cmov opcode for moving the min or max value.
733    MachineBasicBlock *EmitAtomicMinMaxWithCustomInserter(MachineInstr *BInstr,
734                                                          MachineBasicBlock *BB,
735                                                        unsigned cmovOpc) const;
736
737    /// Utility function to emit the xmm reg save portion of va_start.
738    MachineBasicBlock *EmitVAStartSaveXMMRegsWithCustomInserter(
739                                                   MachineInstr *BInstr,
740                                                   MachineBasicBlock *BB) const;
741
742    MachineBasicBlock *EmitLoweredSelect(MachineInstr *I,
743                                         MachineBasicBlock *BB,
744                    DenseMap<MachineBasicBlock*, MachineBasicBlock*> *EM) const;
745
746    /// Emit nodes that will be selected as "test Op0,Op0", or something
747    /// equivalent, for use with the given x86 condition code.
748    SDValue EmitTest(SDValue Op0, unsigned X86CC, SelectionDAG &DAG);
749
750    /// Emit nodes that will be selected as "cmp Op0,Op1", or something
751    /// equivalent, for use with the given x86 condition code.
752    SDValue EmitCmp(SDValue Op0, SDValue Op1, unsigned X86CC,
753                    SelectionDAG &DAG);
754  };
755
756  namespace X86 {
757    FastISel *createFastISel(MachineFunction &mf,
758                           MachineModuleInfo *mmi, DwarfWriter *dw,
759                           DenseMap<const Value *, unsigned> &,
760                           DenseMap<const BasicBlock *, MachineBasicBlock *> &,
761                           DenseMap<const AllocaInst *, int> &
762#ifndef NDEBUG
763                           , SmallSet<Instruction*, 8> &
764#endif
765                           );
766  }
767}
768
769#endif    // X86ISELLOWERING_H
770