1 files changed, 64 insertions, 0 deletions

diff --git a/src/lj_dispatch.h b/src/lj_dispatch.h
new file mode 100644
index 00000000..298aa166
--- /dev/null
+++ b/src/lj_dispatch.h
@@ -0,0 +1,64 @@
+/*
+** Instruction dispatch handling.
+** Copyright (C) 2005-2009 Mike Pall. See Copyright Notice in luajit.h
+*/
+
+#ifndef _LJ_DISPATCH_H
+#define _LJ_DISPATCH_H
+
+#include "lj_obj.h"
+#include "lj_bc.h"
+#if LJ_HASJIT
+#include "lj_jit.h"
+#endif
+
+/* Type of hot counter. Must match the code in the assembler VM. */
+/* 16 bits are sufficient. Only 0.0015% overhead with maximum slot penalty. */
+typedef uint16_t HotCount;
+
+/* Number of hot counter hash table entries (must be a power of two). */
+#define HOTCOUNT_SIZE           64
+#define HOTCOUNT_PCMASK         ((HOTCOUNT_SIZE-1)*sizeof(HotCount))
+#define HOTCOUNT_MIN_PENALTY    103
+#define HOTCOUNT_MAX_PENALTY    60000
+
+/* Global state, main thread and extra fields are allocated together. */
+typedef struct GG_State {
+  lua_State L;                          /* Main thread. */
+  global_State g;                       /* Global state. */
+#if LJ_HASJIT
+  jit_State J;                          /* JIT state. */
+  HotCount hotcount[HOTCOUNT_SIZE];     /* Hot counters. */
+#endif
+  ASMFunction dispatch[2*BC__MAX];      /* Instruction dispatch tables. */
+} GG_State;
+
+#define GG_DISP_STATIC  BC__MAX
+
+#define GG_OFS(field)   ((int)offsetof(GG_State, field))
+#define G2GG(gl) \
+  ((GG_State *)(((char *)(gl))-((char *)(&((GG_State *)0)->g))))
+#define J2GG(j) \
+  ((GG_State *)(((char *)(j))-((char *)(&((GG_State *)0)->J))))
+#define L2GG(L)         G2GG(G(L))
+#define J2G(J)          (&J2GG(J)->g)
+#define G2J(gl)         (&G2GG(gl)->J)
+#define L2J(L)          (&L2GG(L)->J)
+#define GG_G2DISP       (GG_OFS(dispatch) - GG_OFS(g))
+#define GG_DISP2G       (GG_OFS(g) - GG_OFS(dispatch))
+#define GG_DISP2J       (GG_OFS(J) - GG_OFS(dispatch))
+#define GG_DISP2HOT     (GG_OFS(hotcount) - GG_OFS(dispatch))
+
+#define hotcount_get(gg, pc) \
+  (gg)->hotcount[(u32ptr(pc)>>2) & (HOTCOUNT_SIZE-1)]
+#define hotcount_set(gg, pc, val) \
+  (hotcount_get((gg), (pc)) = (HotCount)(val))
+
+/* Dispatch table management. */
+LJ_FUNC void lj_dispatch_init(GG_State *GG);
+LJ_FUNC void lj_dispatch_update(global_State *g);
+
+/* Instruction dispatch callback for instr/line hooks or when recording. */
+LJ_FUNCA void lj_dispatch_ins(lua_State *L, const BCIns *pc, uint32_t nres);
+
+#endif