aboutsummaryrefslogtreecommitdiff
path: root/lib/Target/MSP430/MSP430ISelLowering.h
blob: e0ed870f56537f1ed085d84c328345e98a1d2f84 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
//===-- MSP430ISelLowering.h - MSP430 DAG Lowering Interface ----*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines the interfaces that MSP430 uses to lower LLVM code into a
// selection DAG.
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_TARGET_MSP430_ISELLOWERING_H
#define LLVM_TARGET_MSP430_ISELLOWERING_H

#include "MSP430.h"
#include "llvm/CodeGen/SelectionDAG.h"
#include "llvm/Target/TargetLowering.h"

namespace llvm {
  namespace MSP430ISD {
    enum {
      FIRST_NUMBER = ISD::BUILTIN_OP_END,

      /// Return with a flag operand. Operand 0 is the chain operand.
      RET_FLAG,

      /// Same as RET_FLAG, but used for returning from ISRs.
      RETI_FLAG,

      /// Y = R{R,L}A X, rotate right (left) arithmetically
      RRA, RLA,

      /// Y = RRC X, rotate right via carry
      RRC,

      /// CALL - These operations represent an abstract call
      /// instruction, which includes a bunch of information.
      CALL,

      /// Wrapper - A wrapper node for TargetConstantPool, TargetExternalSymbol,
      /// and TargetGlobalAddress.
      Wrapper,

      /// CMP - Compare instruction.
      CMP,

      /// SetCC - Operand 0 is condition code, and operand 1 is the flag
      /// operand produced by a CMP instruction.
      SETCC,

      /// MSP430 conditional branches. Operand 0 is the chain operand, operand 1
      /// is the block to branch if condition is true, operand 2 is the
      /// condition code, and operand 3 is the flag operand produced by a CMP
      /// instruction.
      BR_CC,

      /// SELECT_CC - Operand 0 and operand 1 are selection variable, operand 3
      /// is condition code and operand 4 is flag operand.
      SELECT_CC,

      /// SHL, SRA, SRL - Non-constant shifts.
      SHL, SRA, SRL
    };
  }

  class MSP430Subtarget;
  class MSP430TargetMachine;

  class MSP430TargetLowering : public TargetLowering {
  public:
    explicit MSP430TargetLowering(MSP430TargetMachine &TM);

    virtual MVT getScalarShiftAmountTy(EVT LHSTy) const { return MVT::i8; }

    /// LowerOperation - Provide custom lowering hooks for some operations.
    virtual SDValue LowerOperation(SDValue Op, SelectionDAG &DAG) const;

    /// getTargetNodeName - This method returns the name of a target specific
    /// DAG node.
    virtual const char *getTargetNodeName(unsigned Opcode) const;

    SDValue LowerShifts(SDValue Op, SelectionDAG &DAG) const;
    SDValue LowerGlobalAddress(SDValue Op, SelectionDAG &DAG) const;
    SDValue LowerBlockAddress(SDValue Op, SelectionDAG &DAG) const;
    SDValue LowerExternalSymbol(SDValue Op, SelectionDAG &DAG) const;
    SDValue LowerBR_CC(SDValue Op, SelectionDAG &DAG) const;
    SDValue LowerSETCC(SDValue Op, SelectionDAG &DAG) const;
    SDValue LowerSELECT_CC(SDValue Op, SelectionDAG &DAG) const;
    SDValue LowerSIGN_EXTEND(SDValue Op, SelectionDAG &DAG) const;
    SDValue LowerRETURNADDR(SDValue Op, SelectionDAG &DAG) const;
    SDValue LowerFRAMEADDR(SDValue Op, SelectionDAG &DAG) const;
    SDValue LowerVASTART(SDValue Op, SelectionDAG &DAG) const;
    SDValue getReturnAddressFrameIndex(SelectionDAG &DAG) const;

    TargetLowering::ConstraintType
    getConstraintType(const std::string &Constraint) const;
    std::pair<unsigned, const TargetRegisterClass*>
    getRegForInlineAsmConstraint(const std::string &Constraint, EVT VT) const;

    /// isTruncateFree - Return true if it's free to truncate a value of type
    /// Ty1 to type Ty2. e.g. On msp430 it's free to truncate a i16 value in
    /// register R15W to i8 by referencing its sub-register R15B.
    virtual bool isTruncateFree(Type *Ty1, Type *Ty2) const;
    virtual bool isTruncateFree(EVT VT1, EVT VT2) const;

    /// isZExtFree - Return true if any actual instruction that defines a value
    /// of type Ty1 implicit zero-extends the value to Ty2 in the result
    /// register. This does not necessarily include registers defined in unknown
    /// ways, such as incoming arguments, or copies from unknown virtual
    /// registers. Also, if isTruncateFree(Ty2, Ty1) is true, this does not
    /// necessarily apply to truncate instructions. e.g. on msp430, all
    /// instructions that define 8-bit values implicit zero-extend the result
    /// out to 16 bits.
    virtual bool isZExtFree(Type *Ty1, Type *Ty2) const;
    virtual bool isZExtFree(EVT VT1, EVT VT2) const;
    virtual bool isZExtFree(SDValue Val, EVT VT2) const;

    MachineBasicBlock* EmitInstrWithCustomInserter(MachineInstr *MI,
                                                   MachineBasicBlock *BB) const;
    MachineBasicBlock* EmitShiftInstr(MachineInstr *MI,
                                      MachineBasicBlock *BB) const;

  private:
    SDValue LowerCCCCallTo(SDValue Chain, SDValue Callee,
                           CallingConv::ID CallConv, bool isVarArg,
                           bool isTailCall,
                           const SmallVectorImpl<ISD::OutputArg> &Outs,
                           const SmallVectorImpl<SDValue> &OutVals,
                           const SmallVectorImpl<ISD::InputArg> &Ins,
                           DebugLoc dl, SelectionDAG &DAG,
                           SmallVectorImpl<SDValue> &InVals) const;

    SDValue LowerCCCArguments(SDValue Chain,
                              CallingConv::ID CallConv,
                              bool isVarArg,
                              const SmallVectorImpl<ISD::InputArg> &Ins,
                              DebugLoc dl,
                              SelectionDAG &DAG,
                              SmallVectorImpl<SDValue> &InVals) const;

    SDValue LowerCallResult(SDValue Chain, SDValue InFlag,
                            CallingConv::ID CallConv, bool isVarArg,
                            const SmallVectorImpl<ISD::InputArg> &Ins,
                            DebugLoc dl, SelectionDAG &DAG,
                            SmallVectorImpl<SDValue> &InVals) const;

    virtual SDValue
      LowerFormalArguments(SDValue Chain,
                           CallingConv::ID CallConv, bool isVarArg,
                           const SmallVectorImpl<ISD::InputArg> &Ins,
                           DebugLoc dl, SelectionDAG &DAG,
                           SmallVectorImpl<SDValue> &InVals) const;
    virtual SDValue
      LowerCall(TargetLowering::CallLoweringInfo &CLI,
                SmallVectorImpl<SDValue> &InVals) const;

    virtual SDValue
      LowerReturn(SDValue Chain,
                  CallingConv::ID CallConv, bool isVarArg,
                  const SmallVectorImpl<ISD::OutputArg> &Outs,
                  const SmallVectorImpl<SDValue> &OutVals,
                  DebugLoc dl, SelectionDAG &DAG) const;

    virtual bool getPostIndexedAddressParts(SDNode *N, SDNode *Op,
                                            SDValue &Base,
                                            SDValue &Offset,
                                            ISD::MemIndexedMode &AM,
                                            SelectionDAG &DAG) const;

    const MSP430Subtarget &Subtarget;
    const DataLayout *TD;
  };
} // namespace llvm

#endif // LLVM_TARGET_MSP430_ISELLOWERING_H