include/jitcs_memref.h

   1 //===-- jitcs_memref.h - memory parameters in instructions -----*- C++ -*-===//
   2 //
   3 // A MemoryReference contains all data necessary to describe the memory
   4 // parameter of a single hardware instruction. If a MemoryReference contains
   5 // uses of a non-fixed virtual register, and is used in more than one
   6 // instruction, copies will be created at register allocation time.
   7 //
   8 // TODO: The source looks rather ugly right now.
   9 //
  10 //===----------------------------------------------------------------------===//
  11
  12 #ifndef _JITCS_MEMREF_H_
  13 #define _JITCS_MEMREF_H_
  14
  15 #include "jitcs_base.h"
  16 #include "jitcs_ids.h"
  17
  18 namespace jitcs {
  19 struct VirtualRegister;
  20
  21 template <int N> struct MemDataImpl {};
  22 template <> struct MemDataImpl<4> {
  23   union {
  24     struct { VirtualRegister const *base, *index; } regs;
  25     struct { u8* ptr; } global;
  26   };
  27   int offset;
  28   int modeAndScale;
  29 };
  30 template <> struct MemDataImpl<8> {
  31   union {
  32     struct { VirtualRegister const *base, *index; } regs;
  33     struct { u8* ptr; } global;
  34   };
  35   int offset;
  36   int modeAndScale;
  37   iptr _padding;
  38 };
  39
  40 typedef MemDataImpl<sizeof(void*)> MemData;
  41 static_assert((sizeof(MemData)&~15) == 0);
  42
  43 struct MemoryReference : MemData {
  44   void setVRegSpillSlot(Ref<VirtualRegister> id) {
  45     regs.base = id;
  46     regs.index = nullptr;
  47     offset = 0;
  48     modeAndScale = MMODE_VRegSpillSlot;
  49   }
  50   void setBaseAndOffset(Ref<VirtualRegister> id, int o) {
  51     regs.base = id;
  52     regs.index = nullptr;
  53     offset = o;
  54     modeAndScale = MMODE_Base;
  55   }
  56   void setBaseIndexAndOffset(Ref<VirtualRegister> id, Ref<VirtualRegister> id2, int s, int o) {
  57     regs.base = id;
  58     regs.index = id2;
  59     offset = o;
  60     modeAndScale = MMODE_Base + (s << MMODE_Bits);
  61   }
  62   void setFPRelative(uint fp, int o) {
  63     assert(fp >= 0 && fp < MMODE_FPCount);
  64     offset = o;
  65     modeAndScale = MMODE_SPRel + fp;
  66   }
  67   inline void setSPRelative(int o) {
  68     setFPRelative(0, o);
  69   }
  70   void setGlobal(u8* p, int o) {
  71     global.ptr = p;
  72     offset = o;
  73     modeAndScale = MMODE_Global;
  74   }
  75
  76   MMode getMode() const { return static_cast<MMode>(modeAndScale &  MMODE_Mask); }
  77   int getScale() const { return modeAndScale >> MMODE_Mask; }
  78   int getOffset() const { return offset; }
  79   RefOrNull<VirtualRegister> getBaseReg() const  { return regs.base; }
  80   RefOrNull<VirtualRegister> getIndexReg() const { return regs.index; }
  81   const u8* getGlobal() const { return global.ptr; }
  82
  83   void setBaseReg(RefOrNull<VirtualRegister> r) { regs.base = r; }
  84   void setIndexReg(RefOrNull<VirtualRegister> r) { regs.index = r; }
  85 };
  86
  87 } // end of namespace jitcs
  88
  89 #endif
  90 // _JITCS_MEMREF_H_