1 //===-- LanaiISelLowering.h - Lanai 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 Lanai uses to lower LLVM code into a
11 // selection DAG.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #ifndef LLVM_LIB_TARGET_LANAI_LANAIISELLOWERING_H
16 #define LLVM_LIB_TARGET_LANAI_LANAIISELLOWERING_H
17 
18 #include "Lanai.h"
19 #include "LanaiRegisterInfo.h"
20 #include "llvm/CodeGen/SelectionDAG.h"
21 #include "llvm/CodeGen/TargetLowering.h"
22 
23 namespace llvm {
24 namespace LanaiISD {
25 enum {
26   FIRST_NUMBER = ISD::BUILTIN_OP_END,
27 
28   ADJDYNALLOC,
29 
30   // Return with a flag operand. Operand 0 is the chain operand.
31   RET_FLAG,
32 
33   // CALL - These operations represent an abstract call instruction, which
34   // includes a bunch of information.
35   CALL,
36 
37   // SELECT_CC - Operand 0 and operand 1 are selection variable, operand 3
38   // is condition code and operand 4 is flag operand.
39   SELECT_CC,
40 
41   // SETCC - Store the conditional code to a register.
42   SETCC,
43 
44   // SET_FLAG - Set flag compare.
45   SET_FLAG,
46 
47   // SUBBF - Subtract with borrow that sets flags.
48   SUBBF,
49 
50   // BR_CC - Used to glue together a conditional branch and comparison
51   BR_CC,
52 
53   // Wrapper - A wrapper node for TargetConstantPool, TargetExternalSymbol,
54   // and TargetGlobalAddress.
55   Wrapper,
56 
57   // Get the Higher/Lower 16 bits from a 32-bit immediate.
58   HI,
59   LO,
60 
61   // Small 21-bit immediate in global memory.
62   SMALL
63 };
64 } // namespace LanaiISD
65 
66 class LanaiSubtarget;
67 
68 class LanaiTargetLowering : public TargetLowering {
69 public:
70   LanaiTargetLowering(const TargetMachine &TM, const LanaiSubtarget &STI);
71 
72   // LowerOperation - Provide custom lowering hooks for some operations.
73   SDValue LowerOperation(SDValue Op, SelectionDAG &DAG) const override;
74 
75   // getTargetNodeName - This method returns the name of a target specific
76   // DAG node.
77   const char *getTargetNodeName(unsigned Opcode) const override;
78 
79   SDValue LowerBlockAddress(SDValue Op, SelectionDAG &DAG) const;
80   SDValue LowerBR_CC(SDValue Op, SelectionDAG &DAG) const;
81   SDValue LowerConstantPool(SDValue Op, SelectionDAG &DAG) const;
82   SDValue LowerDYNAMIC_STACKALLOC(SDValue Op, SelectionDAG &DAG) const;
83   SDValue LowerFRAMEADDR(SDValue Op, SelectionDAG &DAG) const;
84   SDValue LowerGlobalAddress(SDValue Op, SelectionDAG &DAG) const;
85   SDValue LowerJumpTable(SDValue Op, SelectionDAG &DAG) const;
86   SDValue LowerMUL(SDValue Op, SelectionDAG &DAG) const;
87   SDValue LowerRETURNADDR(SDValue Op, SelectionDAG &DAG) const;
88   SDValue LowerSELECT_CC(SDValue Op, SelectionDAG &DAG) const;
89   SDValue LowerSETCC(SDValue Op, SelectionDAG &DAG) const;
90   SDValue LowerSHL_PARTS(SDValue Op, SelectionDAG &DAG) const;
91   SDValue LowerSRL_PARTS(SDValue Op, SelectionDAG &DAG) const;
92   SDValue LowerVASTART(SDValue Op, SelectionDAG &DAG) const;
93 
94   unsigned getRegisterByName(const char *RegName, EVT VT,
95                              SelectionDAG &DAG) const override;
96   std::pair<unsigned, const TargetRegisterClass *>
97   getRegForInlineAsmConstraint(const TargetRegisterInfo *TRI,
98                                StringRef Constraint, MVT VT) const override;
99   ConstraintWeight
100   getSingleConstraintMatchWeight(AsmOperandInfo &Info,
101                                  const char *Constraint) const override;
102   void LowerAsmOperandForConstraint(SDValue Op, std::string &Constraint,
103                                     std::vector<SDValue> &Ops,
104                                     SelectionDAG &DAG) const override;
105 
106   SDValue PerformDAGCombine(SDNode *N, DAGCombinerInfo &DCI) const override;
107 
108   void computeKnownBitsForTargetNode(const SDValue Op, KnownBits &Known,
109                                      const APInt &DemandedElts,
110                                      const SelectionDAG &DAG,
111                                      unsigned Depth = 0) const override;
112 
113 private:
114   SDValue LowerCCCCallTo(SDValue Chain, SDValue Callee,
115                          CallingConv::ID CallConv, bool IsVarArg,
116                          bool IsTailCall,
117                          const SmallVectorImpl<ISD::OutputArg> &Outs,
118                          const SmallVectorImpl<SDValue> &OutVals,
119                          const SmallVectorImpl<ISD::InputArg> &Ins,
120                          const SDLoc &dl, SelectionDAG &DAG,
121                          SmallVectorImpl<SDValue> &InVals) const;
122 
123   SDValue LowerCCCArguments(SDValue Chain, CallingConv::ID CallConv,
124                             bool IsVarArg,
125                             const SmallVectorImpl<ISD::InputArg> &Ins,
126                             const SDLoc &DL, SelectionDAG &DAG,
127                             SmallVectorImpl<SDValue> &InVals) const;
128 
129   SDValue LowerCallResult(SDValue Chain, SDValue InFlag,
130                           CallingConv::ID CallConv, bool IsVarArg,
131                           const SmallVectorImpl<ISD::InputArg> &Ins,
132                           const SDLoc &DL, SelectionDAG &DAG,
133                           SmallVectorImpl<SDValue> &InVals) const;
134 
135   SDValue LowerCall(TargetLowering::CallLoweringInfo &CLI,
136                     SmallVectorImpl<SDValue> &InVals) const override;
137 
138   SDValue LowerFormalArguments(SDValue Chain, CallingConv::ID CallConv,
139                                bool IsVarArg,
140                                const SmallVectorImpl<ISD::InputArg> &Ins,
141                                const SDLoc &DL, SelectionDAG &DAG,
142                                SmallVectorImpl<SDValue> &InVals) const override;
143 
144   SDValue LowerReturn(SDValue Chain, CallingConv::ID CallConv, bool IsVarArg,
145                       const SmallVectorImpl<ISD::OutputArg> &Outs,
146                       const SmallVectorImpl<SDValue> &OutVals, const SDLoc &DL,
147                       SelectionDAG &DAG) const override;
148 
149   const LanaiRegisterInfo *TRI;
150 };
151 } // namespace llvm
152 
153 #endif // LLVM_LIB_TARGET_LANAI_LANAIISELLOWERING_H
154