src/lj_dispatch.h

   1 /*
   2 ** Instruction dispatch handling.
   3 ** Copyright (C) 2005-2017 Mike Pall. See Copyright Notice in luajit.h
   4 */
   5
   6 #ifndef _LJ_DISPATCH_H
   7 #define _LJ_DISPATCH_H
   8
   9 #include "lj_obj.h"
  10 #include "lj_bc.h"
  11 #if LJ_HASJIT
  12 #include "lj_jit.h"
  13 #endif
  14
  15 #if LJ_TARGET_MIPS
  16 /* Need our own global offset table for the dreaded MIPS calling conventions. */
  17 #if LJ_HASJIT
  18 #define JITGOTDEF(_)    _(lj_trace_exit) _(lj_trace_hot)
  19 #else
  20 #define JITGOTDEF(_)
  21 #endif
  22 #if LJ_HASFFI
  23 #define FFIGOTDEF(_) \
  24   _(lj_meta_equal_cd) _(lj_ccallback_enter) _(lj_ccallback_leave)
  25 #else
  26 #define FFIGOTDEF(_)
  27 #endif
  28 #define GOTDEF(_) \
  29   _(floor) _(ceil) _(trunc) _(log) _(log10) _(exp) _(sin) _(cos) _(tan) \
  30   _(asin) _(acos) _(atan) _(sinh) _(cosh) _(tanh) _(frexp) _(modf) _(atan2) \
  31   _(pow) _(fmod) _(ldexp) \
  32   _(lj_dispatch_call) _(lj_dispatch_ins) _(lj_err_throw) \
  33   _(lj_ffh_coroutine_wrap_err) _(lj_func_closeuv) _(lj_func_newL_gc) \
  34   _(lj_gc_barrieruv) _(lj_gc_step) _(lj_gc_step_fixtop) _(lj_meta_arith) \
  35   _(lj_meta_call) _(lj_meta_cat) _(lj_meta_comp) _(lj_meta_equal) \
  36   _(lj_meta_for) _(lj_meta_len) _(lj_meta_tget) _(lj_meta_tset) \
  37   _(lj_state_growstack) _(lj_str_fromnum) _(lj_str_fromnumber) _(lj_str_new) \
  38   _(lj_tab_dup) _(lj_tab_get) _(lj_tab_getinth) _(lj_tab_len) _(lj_tab_new) \
  39   _(lj_tab_newkey) _(lj_tab_next) _(lj_tab_reasize) \
  40   JITGOTDEF(_) FFIGOTDEF(_)
  41
  42 enum {
  43 #define GOTENUM(name) LJ_GOT_##name,
  44 GOTDEF(GOTENUM)
  45 #undef GOTENUM
  46   LJ_GOT__MAX
  47 };
  48 #endif
  49
  50 /* Type of hot counter. Must match the code in the assembler VM. */
  51 /* 16 bits are sufficient. Only 0.0015% overhead with maximum slot penalty. */
  52 typedef uint16_t HotCount;
  53
  54 /* Number of hot counter hash table entries (must be a power of two). */
  55 #define HOTCOUNT_SIZE           64
  56 #define HOTCOUNT_PCMASK         ((HOTCOUNT_SIZE-1)*sizeof(HotCount))
  57
  58 /* Hotcount decrements. */
  59 #define HOTCOUNT_LOOP           2
  60 #define HOTCOUNT_CALL           1
  61
  62 /* This solves a circular dependency problem -- bump as needed. Sigh. */
  63 #define GG_NUM_ASMFF    62
  64
  65 #define GG_LEN_DDISP    (BC__MAX + GG_NUM_ASMFF)
  66 #define GG_LEN_SDISP    BC_FUNCF
  67 #define GG_LEN_DISP     (GG_LEN_DDISP + GG_LEN_SDISP)
  68
  69 /* Global state, main thread and extra fields are allocated together. */
  70 typedef struct GG_State {
  71   lua_State L;                          /* Main thread. */
  72   global_State g;                       /* Global state. */
  73 #if LJ_TARGET_MIPS
  74   ASMFunction got[LJ_GOT__MAX];         /* Global offset table. */
  75 #endif
  76 #if LJ_HASJIT
  77   jit_State J;                          /* JIT state. */
  78   HotCount hotcount[HOTCOUNT_SIZE];     /* Hot counters. */
  79 #endif
  80   ASMFunction dispatch[GG_LEN_DISP];    /* Instruction dispatch tables. */
  81   BCIns bcff[GG_NUM_ASMFF];             /* Bytecode for ASM fast functions. */
  82 } GG_State;
  83
  84 #define GG_OFS(field)   ((int)offsetof(GG_State, field))
  85 #define G2GG(gl)        ((GG_State *)((char *)(gl) - GG_OFS(g)))
  86 #define J2GG(j)         ((GG_State *)((char *)(j) - GG_OFS(J)))
  87 #define L2GG(L)         (G2GG(G(L)))
  88 #define J2G(J)          (&J2GG(J)->g)
  89 #define G2J(gl)         (&G2GG(gl)->J)
  90 #define L2J(L)          (&L2GG(L)->J)
  91 #define GG_G2DISP       (GG_OFS(dispatch) - GG_OFS(g))
  92 #define GG_DISP2G       (GG_OFS(g) - GG_OFS(dispatch))
  93 #define GG_DISP2J       (GG_OFS(J) - GG_OFS(dispatch))
  94 #define GG_DISP2HOT     (GG_OFS(hotcount) - GG_OFS(dispatch))
  95 #define GG_DISP2STATIC  (GG_LEN_DDISP*(int)sizeof(ASMFunction))
  96
  97 #define hotcount_get(gg, pc) \
  98   (gg)->hotcount[(u32ptr(pc)>>2) & (HOTCOUNT_SIZE-1)]
  99 #define hotcount_set(gg, pc, val) \
 100   (hotcount_get((gg), (pc)) = (HotCount)(val))
 101
 102 /* Dispatch table management. */
 103 LJ_FUNC void lj_dispatch_init(GG_State *GG);
 104 #if LJ_HASJIT
 105 LJ_FUNC void lj_dispatch_init_hotcount(global_State *g);
 106 #endif
 107 LJ_FUNC void lj_dispatch_update(global_State *g);
 108
 109 /* Instruction dispatch callback for hooks or when recording. */
 110 LJ_FUNCA void LJ_FASTCALL lj_dispatch_ins(lua_State *L, const BCIns *pc);
 111 LJ_FUNCA ASMFunction LJ_FASTCALL lj_dispatch_call(lua_State *L, const BCIns*pc);
 112 LJ_FUNCA void LJ_FASTCALL lj_dispatch_return(lua_State *L, const BCIns *pc);
 113
 114 #if LJ_HASFFI && !defined(_BUILDVM_H)
 115 /* Save/restore errno and GetLastError() around hooks, exits and recording. */
 116 #include <errno.h>
 117 #if LJ_TARGET_WINDOWS
 118 #define WIN32_LEAN_AND_MEAN
 119 #include <windows.h>
 120 #define ERRNO_SAVE      int olderr = errno; DWORD oldwerr = GetLastError();
 121 #define ERRNO_RESTORE   errno = olderr; SetLastError(oldwerr);
 122 #else
 123 #define ERRNO_SAVE      int olderr = errno;
 124 #define ERRNO_RESTORE   errno = olderr;
 125 #endif
 126 #else
 127 #define ERRNO_SAVE
 128 #define ERRNO_RESTORE
 129 #endif
 130
 131 #endif