ARMISelLowering.h revision b36ec86c01e3c3238dca621648f017aef96dda60 
1//===-- ARMISelLowering.h - ARM 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 ARM uses to lower LLVM code into a
11// selection DAG.
12//
13//===----------------------------------------------------------------------===//
14
15#ifndef ARMISELLOWERING_H
16#define ARMISELLOWERING_H
17
18#include "ARMSubtarget.h"
19#include "llvm/Target/TargetLowering.h"
20#include "llvm/CodeGen/SelectionDAG.h"
21#include "llvm/CodeGen/CallingConvLower.h"
22#include <vector>
23
24namespace llvm {
25  class ARMConstantPoolValue;
26
27  namespace ARMISD {
28    // ARM Specific DAG Nodes
29    enum NodeType {
30      // Start the numbering where the builtin ops and target ops leave off.
31      FIRST_NUMBER = ISD::BUILTIN_OP_END,
32
33      Wrapper,      // Wrapper - A wrapper node for TargetConstantPool,
34                    // TargetExternalSymbol, and TargetGlobalAddress.
35      WrapperJT,    // WrapperJT - A wrapper node for TargetJumpTable
36
37      CALL,         // Function call.
38      CALL_PRED,    // Function call that's predicable.
39      CALL_NOLINK,  // Function call with branch not branch-and-link.
40      tCALL,        // Thumb function call.
41      BRCOND,       // Conditional branch.
42      BR_JT,        // Jumptable branch.
43      BR2_JT,       // Jumptable branch (2 level - jumptable entry is a jump).
44      RET_FLAG,     // Return with a flag operand.
45
46      PIC_ADD,      // Add with a PC operand and a PIC label.
47
48      CMP,          // ARM compare instructions.
49      CMPZ,         // ARM compare that sets only Z flag.
50      CMPFP,        // ARM VFP compare instruction, sets FPSCR.
51      CMPFPw0,      // ARM VFP compare against zero instruction, sets FPSCR.
52      FMSTAT,       // ARM fmstat instruction.
53      CMOV,         // ARM conditional move instructions.
54      CNEG,         // ARM conditional negate instructions.
55
56      FTOSI,        // FP to sint within a FP register.
57      FTOUI,        // FP to uint within a FP register.
58      SITOF,        // sint to FP within a FP register.
59      UITOF,        // uint to FP within a FP register.
60
61      SRL_FLAG,     // V,Flag = srl_flag X -> srl X, 1 + save carry out.
62      SRA_FLAG,     // V,Flag = sra_flag X -> sra X, 1 + save carry out.
63      RRX,          // V = RRX X, Flag     -> srl X, 1 + shift in carry flag.
64
65      FMRRD,        // double to two gprs.
66      FMDRR,        // Two gprs to double.
67
68      EH_SJLJ_SETJMP,    // SjLj exception handling setjmp
69      EH_SJLJ_LONGJMP,   // SjLj exception handling longjmp
70
71      THREAD_POINTER,
72
73      VCEQ,         // Vector compare equal.
74      VCGE,         // Vector compare greater than or equal.
75      VCGEU,        // Vector compare unsigned greater than or equal.
76      VCGT,         // Vector compare greater than.
77      VCGTU,        // Vector compare unsigned greater than.
78      VTST,         // Vector test bits.
79
80      // Vector shift by immediate:
81      VSHL,         // ...left
82      VSHRs,        // ...right (signed)
83      VSHRu,        // ...right (unsigned)
84      VSHLLs,       // ...left long (signed)
85      VSHLLu,       // ...left long (unsigned)
86      VSHLLi,       // ...left long (with maximum shift count)
87      VSHRN,        // ...right narrow
88
89      // Vector rounding shift by immediate:
90      VRSHRs,       // ...right (signed)
91      VRSHRu,       // ...right (unsigned)
92      VRSHRN,       // ...right narrow
93
94      // Vector saturating shift by immediate:
95      VQSHLs,       // ...left (signed)
96      VQSHLu,       // ...left (unsigned)
97      VQSHLsu,      // ...left (signed to unsigned)
98      VQSHRNs,      // ...right narrow (signed)
99      VQSHRNu,      // ...right narrow (unsigned)
100      VQSHRNsu,     // ...right narrow (signed to unsigned)
101
102      // Vector saturating rounding shift by immediate:
103      VQRSHRNs,     // ...right narrow (signed)
104      VQRSHRNu,     // ...right narrow (unsigned)
105      VQRSHRNsu,    // ...right narrow (signed to unsigned)
106
107      // Vector shift and insert:
108      VSLI,         // ...left
109      VSRI,         // ...right
110
111      // Vector get lane (VMOV scalar to ARM core register)
112      // (These are used for 8- and 16-bit element types only.)
113      VGETLANEu,    // zero-extend vector extract element
114      VGETLANEs,    // sign-extend vector extract element
115
116      // Vector duplicate lane (128-bit result only; 64-bit is a shuffle)
117      VDUPLANEQ,    // splat a lane from a 64-bit vector to a 128-bit vector
118
119      // Vector load/store with (de)interleaving
120      VLD2D,
121      VLD3D,
122      VLD4D,
123      VST2D,
124      VST3D,
125      VST4D
126    };
127  }
128
129  /// Define some predicates that are used for node matching.
130  namespace ARM {
131    /// getVMOVImm - If this is a build_vector of constants which can be
132    /// formed by using a VMOV instruction of the specified element size,
133    /// return the constant being splatted.  The ByteSize field indicates the
134    /// number of bytes of each element [1248].
135    SDValue getVMOVImm(SDNode *N, unsigned ByteSize, SelectionDAG &DAG);
136
137    /// isVREVMask - Check if a vector shuffle corresponds to a VREV
138    /// instruction with the specified blocksize.  (The order of the elements
139    /// within each block of the vector is reversed.)
140    bool isVREVMask(ShuffleVectorSDNode *N, unsigned blocksize);
141  }
142
143  //===--------------------------------------------------------------------===//
144  //  ARMTargetLowering - ARM Implementation of the TargetLowering interface
145
146  class ARMTargetLowering : public TargetLowering {
147    int VarArgsFrameIndex;            // FrameIndex for start of varargs area.
148  public:
149    explicit ARMTargetLowering(TargetMachine &TM);
150
151    virtual SDValue LowerOperation(SDValue Op, SelectionDAG &DAG);
152
153    /// ReplaceNodeResults - Replace the results of node with an illegal result
154    /// type with new values built out of custom code.
155    ///
156    virtual void ReplaceNodeResults(SDNode *N, SmallVectorImpl<SDValue>&Results,
157                                    SelectionDAG &DAG);
158
159    virtual SDValue PerformDAGCombine(SDNode *N, DAGCombinerInfo &DCI) const;
160
161    virtual const char *getTargetNodeName(unsigned Opcode) const;
162
163    virtual MachineBasicBlock *EmitInstrWithCustomInserter(MachineInstr *MI,
164                                                  MachineBasicBlock *MBB) const;
165
166    /// isLegalAddressingMode - Return true if the addressing mode represented
167    /// by AM is legal for this target, for a load/store of the specified type.
168    virtual bool isLegalAddressingMode(const AddrMode &AM, const Type *Ty)const;
169
170    /// getPreIndexedAddressParts - returns true by value, base pointer and
171    /// offset pointer and addressing mode by reference if the node's address
172    /// can be legally represented as pre-indexed load / store address.
173    virtual bool getPreIndexedAddressParts(SDNode *N, SDValue &Base,
174                                           SDValue &Offset,
175                                           ISD::MemIndexedMode &AM,
176                                           SelectionDAG &DAG) const;
177
178    /// getPostIndexedAddressParts - returns true by value, base pointer and
179    /// offset pointer and addressing mode by reference if this node can be
180    /// combined with a load / store to form a post-indexed load / store.
181    virtual bool getPostIndexedAddressParts(SDNode *N, SDNode *Op,
182                                            SDValue &Base, SDValue &Offset,
183                                            ISD::MemIndexedMode &AM,
184                                            SelectionDAG &DAG) const;
185
186    virtual void computeMaskedBitsForTargetNode(const SDValue Op,
187                                                const APInt &Mask,
188                                                APInt &KnownZero,
189                                                APInt &KnownOne,
190                                                const SelectionDAG &DAG,
191                                                unsigned Depth) const;
192    ConstraintType getConstraintType(const std::string &Constraint) const;
193    std::pair<unsigned, const TargetRegisterClass*>
194      getRegForInlineAsmConstraint(const std::string &Constraint,
195                                   MVT VT) const;
196    std::vector<unsigned>
197    getRegClassForInlineAsmConstraint(const std::string &Constraint,
198                                      MVT VT) const;
199
200    /// LowerAsmOperandForConstraint - Lower the specified operand into the Ops
201    /// vector.  If it is invalid, don't add anything to Ops. If hasMemory is
202    /// true it means one of the asm constraint of the inline asm instruction
203    /// being processed is 'm'.
204    virtual void LowerAsmOperandForConstraint(SDValue Op,
205                                              char ConstraintLetter,
206                                              bool hasMemory,
207                                              std::vector<SDValue> &Ops,
208                                              SelectionDAG &DAG) const;
209
210    virtual const ARMSubtarget* getSubtarget() {
211      return Subtarget;
212    }
213
214    /// getFunctionAlignment - Return the Log2 alignment of this function.
215    virtual unsigned getFunctionAlignment(const Function *F) const;
216
217  private:
218    /// Subtarget - Keep a pointer to the ARMSubtarget around so that we can
219    /// make the right decision when generating code for different targets.
220    const ARMSubtarget *Subtarget;
221
222    /// ARMPCLabelIndex - Keep track of the number of ARM PC labels created.
223    ///
224    unsigned ARMPCLabelIndex;
225
226    void addTypeForNEON(MVT VT, MVT PromotedLdStVT, MVT PromotedBitwiseVT);
227    void addDRTypeForNEON(MVT VT);
228    void addQRTypeForNEON(MVT VT);
229
230    typedef SmallVector<std::pair<unsigned, SDValue>, 8> RegsToPassVector;
231    void PassF64ArgInRegs(DebugLoc dl, SelectionDAG &DAG,
232                          SDValue Chain, SDValue &Arg,
233                          RegsToPassVector &RegsToPass,
234                          CCValAssign &VA, CCValAssign &NextVA,
235                          SDValue &StackPtr,
236                          SmallVector<SDValue, 8> &MemOpChains,
237                          ISD::ArgFlagsTy Flags);
238    SDValue GetF64FormalArgument(CCValAssign &VA, CCValAssign &NextVA,
239                                 SDValue &Root, SelectionDAG &DAG, DebugLoc dl);
240
241    CCAssignFn *CCAssignFnForNode(unsigned CC, bool Return, bool isVarArg) const;
242    SDValue LowerMemOpCallTo(SDValue Chain, SDValue StackPtr, SDValue Arg,
243                             DebugLoc dl, SelectionDAG &DAG,
244                             const CCValAssign &VA,
245                             ISD::ArgFlagsTy Flags);
246    SDValue LowerINTRINSIC_W_CHAIN(SDValue Op, SelectionDAG &DAG);
247    SDValue LowerINTRINSIC_WO_CHAIN(SDValue Op, SelectionDAG &DAG);
248    SDValue LowerGlobalAddressDarwin(SDValue Op, SelectionDAG &DAG);
249    SDValue LowerGlobalAddressELF(SDValue Op, SelectionDAG &DAG);
250    SDValue LowerGlobalTLSAddress(SDValue Op, SelectionDAG &DAG);
251    SDValue LowerToTLSGeneralDynamicModel(GlobalAddressSDNode *GA,
252                                            SelectionDAG &DAG);
253    SDValue LowerToTLSExecModels(GlobalAddressSDNode *GA,
254                                   SelectionDAG &DAG);
255    SDValue LowerGLOBAL_OFFSET_TABLE(SDValue Op, SelectionDAG &DAG);
256    SDValue LowerBR_JT(SDValue Op, SelectionDAG &DAG);
257    SDValue LowerFRAMEADDR(SDValue Op, SelectionDAG &DAG);
258
259    SDValue EmitTargetCodeForMemcpy(SelectionDAG &DAG, DebugLoc dl,
260                                      SDValue Chain,
261                                      SDValue Dst, SDValue Src,
262                                      SDValue Size, unsigned Align,
263                                      bool AlwaysInline,
264                                      const Value *DstSV, uint64_t DstSVOff,
265                                      const Value *SrcSV, uint64_t SrcSVOff);
266    SDValue LowerCallResult(SDValue Chain, SDValue InFlag,
267                            unsigned CallConv, bool isVarArg,
268                            const SmallVectorImpl<ISD::InputArg> &Ins,
269                            DebugLoc dl, SelectionDAG &DAG,
270                            SmallVectorImpl<SDValue> &InVals);
271
272    virtual SDValue
273      LowerFormalArguments(SDValue Chain,
274                           unsigned CallConv, bool isVarArg,
275                           const SmallVectorImpl<ISD::InputArg> &Ins,
276                           DebugLoc dl, SelectionDAG &DAG,
277                           SmallVectorImpl<SDValue> &InVals);
278
279    virtual SDValue
280      LowerCall(SDValue Chain, SDValue Callee,
281                unsigned CallConv, bool isVarArg,
282                bool isTailCall,
283                const SmallVectorImpl<ISD::OutputArg> &Outs,
284                const SmallVectorImpl<ISD::InputArg> &Ins,
285                DebugLoc dl, SelectionDAG &DAG,
286                SmallVectorImpl<SDValue> &InVals);
287
288    virtual SDValue
289      LowerReturn(SDValue Chain,
290                  unsigned CallConv, bool isVarArg,
291                  const SmallVectorImpl<ISD::OutputArg> &Outs,
292                  DebugLoc dl, SelectionDAG &DAG);
293  };
294}
295
296#endif  // ARMISELLOWERING_H
297