PPCISelLowering.h revision 7ff7e674580adad7a5bccdbd74cf9c9f05e46d0f 
1//===-- PPCISelLowering.h - PPC32 DAG Lowering Interface --------*- C++ -*-===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file was developed by Chris Lattner and is distributed under
6// the University of Illinois Open Source License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file defines the interfaces that PPC uses to lower LLVM code into a
11// selection DAG.
12//
13//===----------------------------------------------------------------------===//
14
15#ifndef LLVM_TARGET_POWERPC_PPC32ISELLOWERING_H
16#define LLVM_TARGET_POWERPC_PPC32ISELLOWERING_H
17
18#include "llvm/Target/TargetLowering.h"
19#include "llvm/CodeGen/SelectionDAG.h"
20#include "PPC.h"
21
22namespace llvm {
23  namespace PPCISD {
24    enum NodeType {
25      // Start the numbering where the builting ops and target ops leave off.
26      FIRST_NUMBER = ISD::BUILTIN_OP_END+PPC::INSTRUCTION_LIST_END,
27
28      /// FSEL - Traditional three-operand fsel node.
29      ///
30      FSEL,
31
32      /// FCFID - The FCFID instruction, taking an f64 operand and producing
33      /// and f64 value containing the FP representation of the integer that
34      /// was temporarily in the f64 operand.
35      FCFID,
36
37      /// FCTI[D,W]Z - The FCTIDZ and FCTIWZ instructions, taking an f32 or f64
38      /// operand, producing an f64 value containing the integer representation
39      /// of that FP value.
40      FCTIDZ, FCTIWZ,
41
42      /// STFIWX - The STFIWX instruction.  The first operand is an input token
43      /// chain, then an f64 value to store, then an address to store it to,
44      /// then a SRCVALUE for the address.
45      STFIWX,
46
47      // VMADDFP, VNMSUBFP - The VMADDFP and VNMSUBFP instructions, taking
48      // three v4f32 operands and producing a v4f32 result.
49      VMADDFP, VNMSUBFP,
50
51      /// VPERM - The PPC VPERM Instruction.
52      ///
53      VPERM,
54
55      /// Hi/Lo - These represent the high and low 16-bit parts of a global
56      /// address respectively.  These nodes have two operands, the first of
57      /// which must be a TargetGlobalAddress, and the second of which must be a
58      /// Constant.  Selected naively, these turn into 'lis G+C' and 'li G+C',
59      /// though these are usually folded into other nodes.
60      Hi, Lo,
61
62      /// GlobalBaseReg - On Darwin, this node represents the result of the mflr
63      /// at function entry, used for PIC code.
64      GlobalBaseReg,
65
66      /// These nodes represent the 32-bit PPC shifts that operate on 6-bit
67      /// shift amounts.  These nodes are generated by the multi-precision shift
68      /// code.
69      SRL, SRA, SHL,
70
71      /// EXTSW_32 - This is the EXTSW instruction for use with "32-bit"
72      /// registers.
73      EXTSW_32,
74
75      /// STD_32 - This is the STD instruction for use with "32-bit" registers.
76      STD_32,
77
78      /// CALL - A function call.
79      CALL,
80
81      /// Return with a flag operand, matched by 'blr'
82      RET_FLAG,
83
84      /// R32 = MFCR(CRREG, INFLAG) - Represents the MFCR/MFOCRF instructions.
85      /// This copies the bits corresponding to the specified CRREG into the
86      /// resultant GPR.  Bits corresponding to other CR regs are undefined.
87      MFCR,
88
89      /// RESVEC = VCMP(LHS, RHS, OPC) - Represents one of the altivec VCMP*
90      /// instructions.  For lack of better number, we use the opcode number
91      /// encoding for the OPC field to identify the compare.  For example, 838
92      /// is VCMPGTSH.
93      VCMP,
94
95      /// RESVEC, OUTFLAG = VCMPo(LHS, RHS, OPC) - Represents one of the
96      /// altivec VCMP*o instructions.  For lack of better number, we use the
97      /// opcode number encoding for the OPC field to identify the compare.  For
98      /// example, 838 is VCMPGTSH.
99      VCMPo
100    };
101  }
102
103  /// Define some predicates that are used for node matching.
104  namespace PPC {
105    /// isSplatShuffleMask - Return true if the specified VECTOR_SHUFFLE operand
106    /// specifies a splat of a single element that is suitable for input to
107    /// VSPLTB/VSPLTH/VSPLTW.
108    bool isSplatShuffleMask(SDNode *N, unsigned EltSize);
109
110    /// getVSPLTImmediate - Return the appropriate VSPLT* immediate to splat the
111    /// specified isSplatShuffleMask VECTOR_SHUFFLE mask.
112    unsigned getVSPLTImmediate(SDNode *N, unsigned EltSize);
113
114    /// isVecSplatImm - Return true if this is a build_vector of constants which
115    /// can be formed by using a vspltis[bhw] instruction.  The ByteSize field
116    /// indicates the number of bytes of each element [124] -> [bhw].
117    bool isVecSplatImm(SDNode *N, unsigned ByteSize, char *Val = 0);
118  }
119
120  class PPCTargetLowering : public TargetLowering {
121    int VarArgsFrameIndex;            // FrameIndex for start of varargs area.
122    int ReturnAddrIndex;              // FrameIndex for return slot.
123  public:
124    PPCTargetLowering(TargetMachine &TM);
125
126    /// getTargetNodeName() - This method returns the name of a target specific
127    /// DAG node.
128    virtual const char *getTargetNodeName(unsigned Opcode) const;
129
130    /// LowerOperation - Provide custom lowering hooks for some operations.
131    ///
132    virtual SDOperand LowerOperation(SDOperand Op, SelectionDAG &DAG);
133
134    virtual SDOperand PerformDAGCombine(SDNode *N, DAGCombinerInfo &DCI) const;
135
136    virtual void computeMaskedBitsForTargetNode(const SDOperand Op,
137                                                uint64_t Mask,
138                                                uint64_t &KnownZero,
139                                                uint64_t &KnownOne,
140                                                unsigned Depth = 0) const;
141    /// LowerArguments - This hook must be implemented to indicate how we should
142    /// lower the arguments for the specified function, into the specified DAG.
143    virtual std::vector<SDOperand>
144      LowerArguments(Function &F, SelectionDAG &DAG);
145
146    /// LowerCallTo - This hook lowers an abstract call to a function into an
147    /// actual call.
148    virtual std::pair<SDOperand, SDOperand>
149      LowerCallTo(SDOperand Chain, const Type *RetTy, bool isVarArg,
150                  unsigned CC,
151                  bool isTailCall, SDOperand Callee, ArgListTy &Args,
152                  SelectionDAG &DAG);
153
154    virtual MachineBasicBlock *InsertAtEndOfBasicBlock(MachineInstr *MI,
155                                                       MachineBasicBlock *MBB);
156
157    ConstraintType getConstraintType(char ConstraintLetter) const;
158    std::vector<unsigned>
159      getRegClassForInlineAsmConstraint(const std::string &Constraint,
160                                        MVT::ValueType VT) const;
161    bool isOperandValidForConstraint(SDOperand Op, char ConstraintLetter);
162
163    /// isLegalAddressImmediate - Return true if the integer value can be used
164    /// as the offset of the target addressing mode.
165    virtual bool isLegalAddressImmediate(int64_t V) const;
166  };
167}
168
169#endif   // LLVM_TARGET_POWERPC_PPC32ISELLOWERING_H
170