src/llvm/include/llvm/Target/TargetSelectionDAGInfo.h

   1 //==-- llvm/Target/TargetSelectionDAGInfo.h - SelectionDAG Info --*- 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 declares the TargetSelectionDAGInfo class, which targets can
  11 // subclass to parameterize the SelectionDAG lowering and instruction
  12 // selection process.
  13 //
  14 //===----------------------------------------------------------------------===//
  15
  16 #ifndef LLVM_TARGET_TARGETSELECTIONDAGINFO_H
  17 #define LLVM_TARGET_TARGETSELECTIONDAGINFO_H
  18
  19 #include "llvm/CodeGen/SelectionDAGNodes.h"
  20
  21 namespace llvm {
  22
  23 class DataLayout;
  24 class TargetMachine;
  25
  26 //===----------------------------------------------------------------------===//
  27 /// TargetSelectionDAGInfo - Targets can subclass this to parameterize the
  28 /// SelectionDAG lowering and instruction selection process.
  29 ///
  30 class TargetSelectionDAGInfo {
  31   TargetSelectionDAGInfo(const TargetSelectionDAGInfo &) LLVM_DELETED_FUNCTION;
  32   void operator=(const TargetSelectionDAGInfo &) LLVM_DELETED_FUNCTION;
  33
  34   const DataLayout *DL;
  35
  36 protected:
  37   const DataLayout *getDataLayout() const { return DL; }
  38
  39 public:
  40   explicit TargetSelectionDAGInfo(const DataLayout *DL);
  41   virtual ~TargetSelectionDAGInfo();
  42
  43   /// EmitTargetCodeForMemcpy - Emit target-specific code that performs a
  44   /// memcpy. This can be used by targets to provide code sequences for cases
  45   /// that don't fit the target's parameters for simple loads/stores and can be
  46   /// more efficient than using a library call. This function can return a null
  47   /// SDValue if the target declines to use custom code and a different
  48   /// lowering strategy should be used.
  49   ///
  50   /// If AlwaysInline is true, the size is constant and the target should not
  51   /// emit any calls and is strongly encouraged to attempt to emit inline code
  52   /// even if it is beyond the usual threshold because this intrinsic is being
  53   /// expanded in a place where calls are not feasible (e.g. within the prologue
  54   /// for another call). If the target chooses to decline an AlwaysInline
  55   /// request here, legalize will resort to using simple loads and stores.
  56   virtual SDValue
  57   EmitTargetCodeForMemcpy(SelectionDAG &DAG, SDLoc dl,
  58                           SDValue Chain,
  59                           SDValue Op1, SDValue Op2,
  60                           SDValue Op3, unsigned Align, bool isVolatile,
  61                           bool AlwaysInline,
  62                           MachinePointerInfo DstPtrInfo,
  63                           MachinePointerInfo SrcPtrInfo) const {
  64     return SDValue();
  65   }
  66
  67   /// EmitTargetCodeForMemmove - Emit target-specific code that performs a
  68   /// memmove. This can be used by targets to provide code sequences for cases
  69   /// that don't fit the target's parameters for simple loads/stores and can be
  70   /// more efficient than using a library call. This function can return a null
  71   /// SDValue if the target declines to use custom code and a different
  72   /// lowering strategy should be used.
  73   virtual SDValue
  74   EmitTargetCodeForMemmove(SelectionDAG &DAG, SDLoc dl,
  75                            SDValue Chain,
  76                            SDValue Op1, SDValue Op2,
  77                            SDValue Op3, unsigned Align, bool isVolatile,
  78                            MachinePointerInfo DstPtrInfo,
  79                            MachinePointerInfo SrcPtrInfo) const {
  80     return SDValue();
  81   }
  82
  83   /// EmitTargetCodeForMemset - Emit target-specific code that performs a
  84   /// memset. This can be used by targets to provide code sequences for cases
  85   /// that don't fit the target's parameters for simple stores and can be more
  86   /// efficient than using a library call. This function can return a null
  87   /// SDValue if the target declines to use custom code and a different
  88   /// lowering strategy should be used.
  89   virtual SDValue
  90   EmitTargetCodeForMemset(SelectionDAG &DAG, SDLoc dl,
  91                           SDValue Chain,
  92                           SDValue Op1, SDValue Op2,
  93                           SDValue Op3, unsigned Align, bool isVolatile,
  94                           MachinePointerInfo DstPtrInfo) const {
  95     return SDValue();
  96   }
  97
  98   /// EmitTargetCodeForMemcmp - Emit target-specific code that performs a
  99   /// memcmp, in cases where that is faster than a libcall.  The first
 100   /// returned SDValue is the result of the memcmp and the second is
 101   /// the chain.  Both SDValues can be null if a normal libcall should
 102   /// be used.
 103   virtual std::pair<SDValue, SDValue>
 104   EmitTargetCodeForMemcmp(SelectionDAG &DAG, SDLoc dl,
 105                           SDValue Chain,
 106                           SDValue Op1, SDValue Op2,
 107                           SDValue Op3, MachinePointerInfo Op1PtrInfo,
 108                           MachinePointerInfo Op2PtrInfo) const {
 109     return std::make_pair(SDValue(), SDValue());
 110   }
 111
 112   /// EmitTargetCodeForMemchr - Emit target-specific code that performs a
 113   /// memchr, in cases where that is faster than a libcall.  The first
 114   /// returned SDValue is the result of the memchr and the second is
 115   /// the chain.  Both SDValues can be null if a normal libcall should
 116   /// be used.
 117   virtual std::pair<SDValue, SDValue>
 118   EmitTargetCodeForMemchr(SelectionDAG &DAG, SDLoc dl, SDValue Chain,
 119                           SDValue Src, SDValue Char, SDValue Length,
 120                           MachinePointerInfo SrcPtrInfo) const {
 121     return std::make_pair(SDValue(), SDValue());
 122   }
 123
 124   /// EmitTargetCodeForStrcpy - Emit target-specific code that performs a
 125   /// strcpy or stpcpy, in cases where that is faster than a libcall.
 126   /// The first returned SDValue is the result of the copy (the start
 127   /// of the destination string for strcpy, a pointer to the null terminator
 128   /// for stpcpy) and the second is the chain.  Both SDValues can be null
 129   /// if a normal libcall should be used.
 130   virtual std::pair<SDValue, SDValue>
 131   EmitTargetCodeForStrcpy(SelectionDAG &DAG, SDLoc DL, SDValue Chain,
 132                           SDValue Dest, SDValue Src,
 133                           MachinePointerInfo DestPtrInfo,
 134                           MachinePointerInfo SrcPtrInfo,
 135                           bool isStpcpy) const {
 136     return std::make_pair(SDValue(), SDValue());
 137   }
 138
 139   /// EmitTargetCodeForStrcmp - Emit target-specific code that performs a
 140   /// strcmp, in cases where that is faster than a libcall.  The first
 141   /// returned SDValue is the result of the strcmp and the second is
 142   /// the chain.  Both SDValues can be null if a normal libcall should
 143   /// be used.
 144   virtual std::pair<SDValue, SDValue>
 145   EmitTargetCodeForStrcmp(SelectionDAG &DAG, SDLoc dl,
 146                           SDValue Chain,
 147                           SDValue Op1, SDValue Op2,
 148                           MachinePointerInfo Op1PtrInfo,
 149                           MachinePointerInfo Op2PtrInfo) const {
 150     return std::make_pair(SDValue(), SDValue());
 151   }
 152
 153   virtual std::pair<SDValue, SDValue>
 154   EmitTargetCodeForStrlen(SelectionDAG &DAG, SDLoc DL, SDValue Chain,
 155                           SDValue Src, MachinePointerInfo SrcPtrInfo) const {
 156     return std::make_pair(SDValue(), SDValue());
 157   }
 158
 159   virtual std::pair<SDValue, SDValue>
 160   EmitTargetCodeForStrnlen(SelectionDAG &DAG, SDLoc DL, SDValue Chain,
 161                            SDValue Src, SDValue MaxLength,
 162                            MachinePointerInfo SrcPtrInfo) const {
 163     return std::make_pair(SDValue(), SDValue());
 164   }
 165 };
 166
 167 } // end llvm namespace
 168
 169 #endif