src/jitcs_int_codegenerator.h

   1 //===-- evm/bblock.h - a single basic block --*- C++ -*-===//
   2 //
   3 // A basic block contains a list of instructions.
   4 //
   5 //===----------------------------------------------------------------------===//
   6
   7 #ifndef _JITCS_INT_CODEGENERATOR_H_
   8 #define _JITCS_INT_CODEGENERATOR_H_
   9
  10 #include "jitcs_base.h"
  11 #include "jitcs_adt_ref.h"
  12 #include "jitcs_adt_refcounter.h"
  13 #include "jitcs_adt_slice.h"
  14 #include "jitcs_int_bblock_impl.h"
  15 #include "jitcs_ids.h"
  16 #include "jitcs_tmpalloc.h"
  17 #include "jitcs_memmgr.h"
  18
  19 namespace jitcs {
  20 class FunctionImpl;
  21 class CFGAnalysis;
  22
  23 class CodeGenerator {
  24 public:
  25   enum RelocType {
  26     REL_PCREL32_TAIL = 32,
  27     REL_PCREL16_TAIL = 16,
  28     REL_PCREL8_TAIL = 8,
  29   };
  30   struct FrameRegisterInfo {
  31     RegId reg;
  32     int ofs;
  33   };
  34
  35 public:
  36   CodeGenerator();
  37   CodeGenerator(const CodeGenerator &) = delete;
  38   void operator=(const CodeGenerator &) = delete;
  39
  40   MemoryMgr::CodeAndData generate(FunctionImpl&, CFGAnalysis const&,
  41                                   MemoryMgr& vm, Slice<u8> data);
  42
  43 public:
  44   // methods for use when generating code
  45   bool hasEstimatedPos(Ref<const BasicBlockImpl> bb) const {
  46     return _testFlags(bb, BBLOC_ESTIMATED);
  47   }
  48   bool hasFinalAddress(Ref<const BasicBlockImpl> bb) const {
  49     return _testFlags(bb, BBLOC_FINAL);
  50   }
  51   bool hasEstimatedOrFinalPos(Ref<const BasicBlockImpl> bb) const {
  52     return _testFlags(bb, BBLOC_ESTIMATED | BBLOC_FINAL);
  53   }
  54   size_t getEstimatedOrFinalPos(Ref<const BasicBlockImpl> bb) const {
  55     return _getPos(bb);
  56   }
  57   Ref<u8> getEstimatedOrFinalAddress(Ref<const BasicBlockImpl> bb) const {
  58     return _codespace._ptr + _getPos(bb);
  59   }
  60   void addRelocation(Ref<const BasicBlockImpl> bb, Ref<u8> x, RelocType rel);
  61
  62   FrameRegisterInfo getFrameRegisterInfo(size_t i) {
  63     assert(i < MMODE_FPCount);
  64     return _frameRegisterInfo[i];
  65   }
  66
  67 private:
  68   enum Layout {
  69     BBLOC_ESTIMATED = 1, // position of this basic block is estimated and cannot be further away
  70     BBLOC_FINAL = 2,     // position of this basic block is precisely defined
  71     BBLOC_SHIFT = 2,     // lowest two bits are flags
  72   };
  73   struct RelocInfo {
  74     RefOrNull<RelocInfo> next;
  75     RefOrNull<u8> tgt;
  76     RelocType type;
  77   };
  78   struct BBlockInfo {
  79     RefOrNull<RelocInfo> relocChain;
  80     size_t posAndFlags;
  81   };
  82
  83 private:
  84   void _setEstimatedPosAndClearChain(Ref<const BasicBlockImpl> bb, size_t x);
  85   void _setFinalPos(Ref<const BasicBlockImpl> bb, size_t x, Ref<u8> y);
  86
  87   bool _testFlags(Ref<const BasicBlockImpl> bb, u8 f) const { return (_bblocks[bb->id()].posAndFlags & f) != 0; }
  88   size_t _getPos(Ref<const BasicBlockImpl> bb) const { return _bblocks[bb->id()].posAndFlags >> BBLOC_SHIFT; }
  89
  90 private:
  91   Slice<BBlockInfo> _bblocks;
  92   StreamAllocator<RelocInfo>* _relocalloc;
  93   Slice<u8> _codespace;
  94   FrameRegisterInfo _frameRegisterInfo[MMODE_FPCount];
  95 };
  96
  97 } // end of namespace jitcs
  98
  99 #endif
 100 // _JITCS_INT_CODEGENERATOR_H_