1/*
2** LuaJIT VM tags, values and objects.
3** Copyright (C) 2005-2014 Mike Pall. See Copyright Notice in luajit.h
4**
5** Portions taken verbatim or adapted from the Lua interpreter.
6** Copyright (C) 1994-2008 Lua.org, PUC-Rio. See Copyright Notice in lua.h
7*/
8
9#ifndef _LJ_OBJ_H
10#define _LJ_OBJ_H
11
12#include "lua.h"
13#include "lj_def.h"
14#include "lj_arch.h"
15
16/* -- Memory references (32 bit address space) ---------------------------- */
17
18/* Memory size. */
19typedef uint32_t MSize;
20
21/* Memory reference */
22typedef struct MRef {
23 uint32_t ptr32; /* Pseudo 32 bit pointer. */
24} MRef;
25
26#define mref(r, t) ((t *)(void *)(uintptr_t)(r).ptr32)
27
28#define setmref(r, p) ((r).ptr32 = (uint32_t)(uintptr_t)(void *)(p))
29#define setmrefr(r, v) ((r).ptr32 = (v).ptr32)
30
31/* -- GC object references (32 bit address space) ------------------------- */
32
33/* GCobj reference */
34typedef struct GCRef {
35 uint32_t gcptr32; /* Pseudo 32 bit pointer. */
36} GCRef;
37
38/* Common GC header for all collectable objects. */
39#define GCHeader GCRef nextgc; uint8_t marked; uint8_t gct
40/* This occupies 6 bytes, so use the next 2 bytes for non-32 bit fields. */
41
42#define gcref(r) ((GCobj *)(uintptr_t)(r).gcptr32)
43#define gcrefp(r, t) ((t *)(void *)(uintptr_t)(r).gcptr32)
44#define gcrefu(r) ((r).gcptr32)
45#define gcrefi(r) ((int32_t)(r).gcptr32)
46#define gcrefeq(r1, r2) ((r1).gcptr32 == (r2).gcptr32)
47#define gcnext(gc) (gcref((gc)->gch.nextgc))
48
49#define setgcref(r, gc) ((r).gcptr32 = (uint32_t)(uintptr_t)&(gc)->gch)
50#define setgcrefi(r, i) ((r).gcptr32 = (uint32_t)(i))
51#define setgcrefp(r, p) ((r).gcptr32 = (uint32_t)(uintptr_t)(p))
52#define setgcrefnull(r) ((r).gcptr32 = 0)
53#define setgcrefr(r, v) ((r).gcptr32 = (v).gcptr32)
54
55/* IMPORTANT NOTE:
56**
57** All uses of the setgcref* macros MUST be accompanied with a write barrier.
58**
59** This is to ensure the integrity of the incremental GC. The invariant
60** to preserve is that a black object never points to a white object.
61** I.e. never store a white object into a field of a black object.
62**
63** It's ok to LEAVE OUT the write barrier ONLY in the following cases:
64** - The source is not a GC object (NULL).
65** - The target is a GC root. I.e. everything in global_State.
66** - The target is a lua_State field (threads are never black).
67** - The target is a stack slot, see setgcV et al.
68** - The target is an open upvalue, i.e. pointing to a stack slot.
69** - The target is a newly created object (i.e. marked white). But make
70** sure nothing invokes the GC inbetween.
71** - The target and the source are the same object (self-reference).
72** - The target already contains the object (e.g. moving elements around).
73**
74** The most common case is a store to a stack slot. All other cases where
75** a barrier has been omitted are annotated with a NOBARRIER comment.
76**
77** The same logic applies for stores to table slots (array part or hash
78** part). ALL uses of lj_tab_set* require a barrier for the stored value
79** *and* the stored key, based on the above rules. In practice this means
80** a barrier is needed if *either* of the key or value are a GC object.
81**
82** It's ok to LEAVE OUT the write barrier in the following special cases:
83** - The stored value is nil. The key doesn't matter because it's either
84** not resurrected or lj_tab_newkey() will take care of the key barrier.
85** - The key doesn't matter if the *previously* stored value is guaranteed
86** to be non-nil (because the key is kept alive in the table).
87** - The key doesn't matter if it's guaranteed not to be part of the table,
88** since lj_tab_newkey() takes care of the key barrier. This applies
89** trivially to new tables, but watch out for resurrected keys. Storing
90** a nil value leaves the key in the table!
91**
92** In case of doubt use lj_gc_anybarriert() as it's rather cheap. It's used
93** by the interpreter for all table stores.
94**
95** Note: In contrast to Lua's GC, LuaJIT's GC does *not* specially mark
96** dead keys in tables. The reference is left in, but it's guaranteed to
97** be never dereferenced as long as the value is nil. It's ok if the key is
98** freed or if any object subsequently gets the same address.
99**
100** Not destroying dead keys helps to keep key hash slots stable. This avoids
101** specialization back-off for HREFK when a value flips between nil and
102** non-nil and the GC gets in the way. It also allows safely hoisting
103** HREF/HREFK across GC steps. Dead keys are only removed if a table is
104** resized (i.e. by NEWREF) and xREF must not be CSEd across a resize.
105**
106** The trade-off is that a write barrier for tables must take the key into
107** account, too. Implicitly resurrecting the key by storing a non-nil value
108** may invalidate the incremental GC invariant.
109*/
110
111/* -- Common type definitions --------------------------------------------- */
112
113/* Types for handling bytecodes. Need this here, details in lj_bc.h. */
114typedef uint32_t BCIns; /* Bytecode instruction. */
115typedef uint32_t BCPos; /* Bytecode position. */
116typedef uint32_t BCReg; /* Bytecode register. */
117typedef int32_t BCLine; /* Bytecode line number. */
118
119/* Internal assembler functions. Never call these directly from C. */
120typedef void (*ASMFunction)(void);
121
122/* Resizable string buffer. Need this here, details in lj_str.h. */
123typedef struct SBuf {
124 char *buf; /* String buffer base. */
125 MSize n; /* String buffer length. */
126 MSize sz; /* String buffer size. */
127} SBuf;
128
129/* -- Tags and values ----------------------------------------------------- */
130
131/* Frame link. */
132typedef union {
133 int32_t ftsz; /* Frame type and size of previous frame. */
134 MRef pcr; /* Overlaps PC for Lua frames. */
135} FrameLink;
136
137/* Tagged value. */
138typedef LJ_ALIGN(8) union TValue {
139 uint64_t u64; /* 64 bit pattern overlaps number. */
140 lua_Number n; /* Number object overlaps split tag/value object. */
141 struct {
142 LJ_ENDIAN_LOHI(
143 union {
144 GCRef gcr; /* GCobj reference (if any). */
145 int32_t i; /* Integer value. */
146 };
147 , uint32_t it; /* Internal object tag. Must overlap MSW of number. */
148 )
149 };
150 struct {
151 LJ_ENDIAN_LOHI(
152 GCRef func; /* Function for next frame (or dummy L). */
153 , FrameLink tp; /* Link to previous frame. */
154 )
155 } fr;
156 struct {
157 LJ_ENDIAN_LOHI(
158 uint32_t lo; /* Lower 32 bits of number. */
159 , uint32_t hi; /* Upper 32 bits of number. */
160 )
161 } u32;
162} TValue;
163
164typedef const TValue cTValue;
165
166#define tvref(r) (mref(r, TValue))
167
168/* More external and GCobj tags for internal objects. */
169#define LAST_TT LUA_TTHREAD
170#define LUA_TPROTO (LAST_TT+1)
171#define LUA_TCDATA (LAST_TT+2)
172
173/* Internal object tags.
174**
175** Internal tags overlap the MSW of a number object (must be a double).
176** Interpreted as a double these are special NaNs. The FPU only generates
177** one type of NaN (0xfff8_0000_0000_0000). So MSWs > 0xfff80000 are available
178** for use as internal tags. Small negative numbers are used to shorten the
179** encoding of type comparisons (reg/mem against sign-ext. 8 bit immediate).
180**
181** ---MSW---.---LSW---
182** primitive types | itype | |
183** lightuserdata | itype | void * | (32 bit platforms)
184** lightuserdata |ffff| void * | (64 bit platforms, 47 bit pointers)
185** GC objects | itype | GCRef |
186** int (LJ_DUALNUM)| itype | int |
187** number -------double------
188**
189** ORDER LJ_T
190** Primitive types nil/false/true must be first, lightuserdata next.
191** GC objects are at the end, table/userdata must be lowest.
192** Also check lj_ir.h for similar ordering constraints.
193*/
194#define LJ_TNIL (~0u)
195#define LJ_TFALSE (~1u)
196#define LJ_TTRUE (~2u)
197#define LJ_TLIGHTUD (~3u)
198#define LJ_TSTR (~4u)
199#define LJ_TUPVAL (~5u)
200#define LJ_TTHREAD (~6u)
201#define LJ_TPROTO (~7u)
202#define LJ_TFUNC (~8u)
203#define LJ_TTRACE (~9u)
204#define LJ_TCDATA (~10u)
205#define LJ_TTAB (~11u)
206#define LJ_TUDATA (~12u)
207/* This is just the canonical number type used in some places. */
208#define LJ_TNUMX (~13u)
209
210/* Integers have itype == LJ_TISNUM doubles have itype < LJ_TISNUM */
211#if LJ_64
212#define LJ_TISNUM 0xfffeffffu
213#else
214#define LJ_TISNUM LJ_TNUMX
215#endif
216#define LJ_TISTRUECOND LJ_TFALSE
217#define LJ_TISPRI LJ_TTRUE
218#define LJ_TISGCV (LJ_TSTR+1)
219#define LJ_TISTABUD LJ_TTAB
220
221/* -- String object ------------------------------------------------------- */
222
223/* String object header. String payload follows. */
224typedef struct GCstr {
225 GCHeader;
226 uint8_t reserved; /* Used by lexer for fast lookup of reserved words. */
227 uint8_t unused;
228 MSize hash; /* Hash of string. */
229 MSize len; /* Size of string. */
230} GCstr;
231
232#define strref(r) (&gcref((r))->str)
233#define strdata(s) ((const char *)((s)+1))
234#define strdatawr(s) ((char *)((s)+1))
235#define strVdata(o) strdata(strV(o))
236#define sizestring(s) (sizeof(struct GCstr)+(s)->len+1)
237
238/* -- Userdata object ----------------------------------------------------- */
239
240/* Userdata object. Payload follows. */
241typedef struct GCudata {
242 GCHeader;
243 uint8_t udtype; /* Userdata type. */
244 uint8_t unused2;
245 GCRef env; /* Should be at same offset in GCfunc. */
246 MSize len; /* Size of payload. */
247 GCRef metatable; /* Must be at same offset in GCtab. */
248 uint32_t align1; /* To force 8 byte alignment of the payload. */
249} GCudata;
250
251/* Userdata types. */
252enum {
253 UDTYPE_USERDATA, /* Regular userdata. */
254 UDTYPE_IO_FILE, /* I/O library FILE. */
255 UDTYPE_FFI_CLIB, /* FFI C library namespace. */
256 UDTYPE__MAX
257};
258
259#define uddata(u) ((void *)((u)+1))
260#define sizeudata(u) (sizeof(struct GCudata)+(u)->len)
261
262/* -- C data object ------------------------------------------------------- */
263
264/* C data object. Payload follows. */
265typedef struct GCcdata {
266 GCHeader;
267 uint16_t ctypeid; /* C type ID. */
268} GCcdata;
269
270/* Prepended to variable-sized or realigned C data objects. */
271typedef struct GCcdataVar {
272 uint16_t offset; /* Offset to allocated memory (relative to GCcdata). */
273 uint16_t extra; /* Extra space allocated (incl. GCcdata + GCcdatav). */
274 MSize len; /* Size of payload. */
275} GCcdataVar;
276
277#define cdataptr(cd) ((void *)((cd)+1))
278#define cdataisv(cd) ((cd)->marked & 0x80)
279#define cdatav(cd) ((GCcdataVar *)((char *)(cd) - sizeof(GCcdataVar)))
280#define cdatavlen(cd) check_exp(cdataisv(cd), cdatav(cd)->len)
281#define sizecdatav(cd) (cdatavlen(cd) + cdatav(cd)->extra)
282#define memcdatav(cd) ((void *)((char *)(cd) - cdatav(cd)->offset))
283
284/* -- Prototype object ---------------------------------------------------- */
285
286#define SCALE_NUM_GCO ((int32_t)sizeof(lua_Number)/sizeof(GCRef))
287#define round_nkgc(n) (((n) + SCALE_NUM_GCO-1) & ~(SCALE_NUM_GCO-1))
288
289typedef struct GCproto {
290 GCHeader;
291 uint8_t numparams; /* Number of parameters. */
292 uint8_t framesize; /* Fixed frame size. */
293 MSize sizebc; /* Number of bytecode instructions. */
294 GCRef gclist;
295 MRef k; /* Split constant array (points to the middle). */
296 MRef uv; /* Upvalue list. local slot|0x8000 or parent uv idx. */
297 MSize sizekgc; /* Number of collectable constants. */
298 MSize sizekn; /* Number of lua_Number constants. */
299 MSize sizept; /* Total size including colocated arrays. */
300 uint8_t sizeuv; /* Number of upvalues. */
301 uint8_t flags; /* Miscellaneous flags (see below). */
302 uint16_t trace; /* Anchor for chain of root traces. */
303 /* ------ The following fields are for debugging/tracebacks only ------ */
304 GCRef chunkname; /* Name of the chunk this function was defined in. */
305 BCLine firstline; /* First line of the function definition. */
306 BCLine numline; /* Number of lines for the function definition. */
307 MRef lineinfo; /* Compressed map from bytecode ins. to source line. */
308 MRef uvinfo; /* Upvalue names. */
309 MRef varinfo; /* Names and compressed extents of local variables. */
310} GCproto;
311
312/* Flags for prototype. */
313#define PROTO_CHILD 0x01 /* Has child prototypes. */
314#define PROTO_VARARG 0x02 /* Vararg function. */
315#define PROTO_FFI 0x04 /* Uses BC_KCDATA for FFI datatypes. */
316#define PROTO_NOJIT 0x08 /* JIT disabled for this function. */
317#define PROTO_ILOOP 0x10 /* Patched bytecode with ILOOP etc. */
318/* Only used during parsing. */
319#define PROTO_HAS_RETURN 0x20 /* Already emitted a return. */
320#define PROTO_FIXUP_RETURN 0x40 /* Need to fixup emitted returns. */
321/* Top bits used for counting created closures. */
322#define PROTO_CLCOUNT 0x20 /* Base of saturating 3 bit counter. */
323#define PROTO_CLC_BITS 3
324#define PROTO_CLC_POLY (3*PROTO_CLCOUNT) /* Polymorphic threshold. */
325
326#define PROTO_UV_LOCAL 0x8000 /* Upvalue for local slot. */
327#define PROTO_UV_IMMUTABLE 0x4000 /* Immutable upvalue. */
328
329#define proto_kgc(pt, idx) \
330 check_exp((uintptr_t)(intptr_t)(idx) >= (uintptr_t)-(intptr_t)(pt)->sizekgc, \
331 gcref(mref((pt)->k, GCRef)[(idx)]))
332#define proto_knumtv(pt, idx) \
333 check_exp((uintptr_t)(idx) < (pt)->sizekn, &mref((pt)->k, TValue)[(idx)])
334#define proto_bc(pt) ((BCIns *)((char *)(pt) + sizeof(GCproto)))
335#define proto_bcpos(pt, pc) ((BCPos)((pc) - proto_bc(pt)))
336#define proto_uv(pt) (mref((pt)->uv, uint16_t))
337
338#define proto_chunkname(pt) (strref((pt)->chunkname))
339#define proto_chunknamestr(pt) (strdata(proto_chunkname((pt))))
340#define proto_lineinfo(pt) (mref((pt)->lineinfo, const void))
341#define proto_uvinfo(pt) (mref((pt)->uvinfo, const uint8_t))
342#define proto_varinfo(pt) (mref((pt)->varinfo, const uint8_t))
343
344/* -- Upvalue object ------------------------------------------------------ */
345
346typedef struct GCupval {
347 GCHeader;
348 uint8_t closed; /* Set if closed (i.e. uv->v == &uv->u.value). */
349 uint8_t immutable; /* Immutable value. */
350 union {
351 TValue tv; /* If closed: the value itself. */
352 struct { /* If open: double linked list, anchored at thread. */
353 GCRef prev;
354 GCRef next;
355 };
356 };
357 MRef v; /* Points to stack slot (open) or above (closed). */
358 uint32_t dhash; /* Disambiguation hash: dh1 != dh2 => cannot alias. */
359} GCupval;
360
361#define uvprev(uv_) (&gcref((uv_)->prev)->uv)
362#define uvnext(uv_) (&gcref((uv_)->next)->uv)
363#define uvval(uv_) (mref((uv_)->v, TValue))
364
365/* -- Function object (closures) ------------------------------------------ */
366
367/* Common header for functions. env should be at same offset in GCudata. */
368#define GCfuncHeader \
369 GCHeader; uint8_t ffid; uint8_t nupvalues; \
370 GCRef env; GCRef gclist; MRef pc
371
372typedef struct GCfuncC {
373 GCfuncHeader;
374 lua_CFunction f; /* C function to be called. */
375 TValue upvalue[1]; /* Array of upvalues (TValue). */
376} GCfuncC;
377
378typedef struct GCfuncL {
379 GCfuncHeader;
380 GCRef uvptr[1]; /* Array of _pointers_ to upvalue objects (GCupval). */
381} GCfuncL;
382
383typedef union GCfunc {
384 GCfuncC c;
385 GCfuncL l;
386} GCfunc;
387
388#define FF_LUA 0
389#define FF_C 1
390#define isluafunc(fn) ((fn)->c.ffid == FF_LUA)
391#define iscfunc(fn) ((fn)->c.ffid == FF_C)
392#define isffunc(fn) ((fn)->c.ffid > FF_C)
393#define funcproto(fn) \
394 check_exp(isluafunc(fn), (GCproto *)(mref((fn)->l.pc, char)-sizeof(GCproto)))
395#define sizeCfunc(n) (sizeof(GCfuncC)-sizeof(TValue)+sizeof(TValue)*(n))
396#define sizeLfunc(n) (sizeof(GCfuncL)-sizeof(GCRef)+sizeof(GCRef)*(n))
397
398/* -- Table object -------------------------------------------------------- */
399
400/* Hash node. */
401typedef struct Node {
402 TValue val; /* Value object. Must be first field. */
403 TValue key; /* Key object. */
404 MRef next; /* Hash chain. */
405 MRef freetop; /* Top of free elements (stored in t->node[0]). */
406} Node;
407
408LJ_STATIC_ASSERT(offsetof(Node, val) == 0);
409
410typedef struct GCtab {
411 GCHeader;
412 uint8_t nomm; /* Negative cache for fast metamethods. */
413 int8_t colo; /* Array colocation. */
414 MRef array; /* Array part. */
415 GCRef gclist;
416 GCRef metatable; /* Must be at same offset in GCudata. */
417 MRef node; /* Hash part. */
418 uint32_t asize; /* Size of array part (keys [0, asize-1]). */
419 uint32_t hmask; /* Hash part mask (size of hash part - 1). */
420} GCtab;
421
422#define sizetabcolo(n) ((n)*sizeof(TValue) + sizeof(GCtab))
423#define tabref(r) (&gcref((r))->tab)
424#define noderef(r) (mref((r), Node))
425#define nextnode(n) (mref((n)->next, Node))
426
427/* -- State objects ------------------------------------------------------- */
428
429/* VM states. */
430enum {
431 LJ_VMST_INTERP, /* Interpreter. */
432 LJ_VMST_C, /* C function. */
433 LJ_VMST_GC, /* Garbage collector. */
434 LJ_VMST_EXIT, /* Trace exit handler. */
435 LJ_VMST_RECORD, /* Trace recorder. */
436 LJ_VMST_OPT, /* Optimizer. */
437 LJ_VMST_ASM, /* Assembler. */
438 LJ_VMST__MAX
439};
440
441#define setvmstate(g, st) ((g)->vmstate = ~LJ_VMST_##st)
442
443/* Metamethods. ORDER MM */
444#ifdef LJ_HASFFI
445#define MMDEF_FFI(_) _(new)
446#else
447#define MMDEF_FFI(_)
448#endif
449
450#if LJ_52 || LJ_HASFFI
451#define MMDEF_PAIRS(_) _(pairs) _(ipairs)
452#else
453#define MMDEF_PAIRS(_)
454#define MM_pairs 255
455#define MM_ipairs 255
456#endif
457
458#define MMDEF(_) \
459 _(index) _(newindex) _(gc) _(mode) _(eq) _(len) \
460 /* Only the above (fast) metamethods are negative cached (max. 8). */ \
461 _(lt) _(le) _(concat) _(call) \
462 /* The following must be in ORDER ARITH. */ \
463 _(add) _(sub) _(mul) _(div) _(mod) _(pow) _(unm) \
464 /* The following are used in the standard libraries. */ \
465 _(metatable) _(tostring) MMDEF_FFI(_) MMDEF_PAIRS(_)
466
467typedef enum {
468#define MMENUM(name) MM_##name,
469MMDEF(MMENUM)
470#undef MMENUM
471 MM__MAX,
472 MM____ = MM__MAX,
473 MM_FAST = MM_len
474} MMS;
475
476/* GC root IDs. */
477typedef enum {
478 GCROOT_MMNAME, /* Metamethod names. */
479 GCROOT_MMNAME_LAST = GCROOT_MMNAME + MM__MAX-1,
480 GCROOT_BASEMT, /* Metatables for base types. */
481 GCROOT_BASEMT_NUM = GCROOT_BASEMT + ~LJ_TNUMX,
482 GCROOT_IO_INPUT, /* Userdata for default I/O input file. */
483 GCROOT_IO_OUTPUT, /* Userdata for default I/O output file. */
484 GCROOT_MAX
485} GCRootID;
486
487#define basemt_it(g, it) ((g)->gcroot[GCROOT_BASEMT+~(it)])
488#define basemt_obj(g, o) ((g)->gcroot[GCROOT_BASEMT+itypemap(o)])
489#define mmname_str(g, mm) (strref((g)->gcroot[GCROOT_MMNAME+(mm)]))
490
491typedef struct GCState {
492 MSize total; /* Memory currently allocated. */
493 MSize threshold; /* Memory threshold. */
494 uint8_t currentwhite; /* Current white color. */
495 uint8_t state; /* GC state. */
496 uint8_t nocdatafin; /* No cdata finalizer called. */
497 uint8_t unused2;
498 MSize sweepstr; /* Sweep position in string table. */
499 GCRef root; /* List of all collectable objects. */
500 MRef sweep; /* Sweep position in root list. */
501 GCRef gray; /* List of gray objects. */
502 GCRef grayagain; /* List of objects for atomic traversal. */
503 GCRef weak; /* List of weak tables (to be cleared). */
504 GCRef mmudata; /* List of userdata (to be finalized). */
505 MSize stepmul; /* Incremental GC step granularity. */
506 MSize debt; /* Debt (how much GC is behind schedule). */
507 MSize estimate; /* Estimate of memory actually in use. */
508 MSize pause; /* Pause between successive GC cycles. */
509} GCState;
510
511/* Global state, shared by all threads of a Lua universe. */
512typedef struct global_State {
513 GCRef *strhash; /* String hash table (hash chain anchors). */
514 MSize strmask; /* String hash mask (size of hash table - 1). */
515 MSize strnum; /* Number of strings in hash table. */
516 lua_Alloc allocf; /* Memory allocator. */
517 void *allocd; /* Memory allocator data. */
518 GCState gc; /* Garbage collector. */
519 SBuf tmpbuf; /* Temporary buffer for string concatenation. */
520 Node nilnode; /* Fallback 1-element hash part (nil key and value). */
521 GCstr strempty; /* Empty string. */
522 uint8_t stremptyz; /* Zero terminator of empty string. */
523 uint8_t hookmask; /* Hook mask. */
524 uint8_t dispatchmode; /* Dispatch mode. */
525 uint8_t vmevmask; /* VM event mask. */
526 GCRef mainthref; /* Link to main thread. */
527 TValue registrytv; /* Anchor for registry. */
528 TValue tmptv, tmptv2; /* Temporary TValues. */
529 GCupval uvhead; /* Head of double-linked list of all open upvalues. */
530 int32_t hookcount; /* Instruction hook countdown. */
531 int32_t hookcstart; /* Start count for instruction hook counter. */
532 lua_Hook hookf; /* Hook function. */
533 lua_CFunction wrapf; /* Wrapper for C function calls. */
534 lua_CFunction panic; /* Called as a last resort for errors. */
535 volatile int32_t vmstate; /* VM state or current JIT code trace number. */
536 BCIns bc_cfunc_int; /* Bytecode for internal C function calls. */
537 BCIns bc_cfunc_ext; /* Bytecode for external C function calls. */
538 GCRef jit_L; /* Current JIT code lua_State or NULL. */
539 MRef jit_base; /* Current JIT code L->base. */
540 MRef ctype_state; /* Pointer to C type state. */
541 GCRef gcroot[GCROOT_MAX]; /* GC roots. */
542} global_State;
543
544#define mainthread(g) (&gcref(g->mainthref)->th)
545#define niltv(L) \
546 check_exp(tvisnil(&G(L)->nilnode.val), &G(L)->nilnode.val)
547#define niltvg(g) \
548 check_exp(tvisnil(&(g)->nilnode.val), &(g)->nilnode.val)
549
550/* Hook management. Hook event masks are defined in lua.h. */
551#define HOOK_EVENTMASK 0x0f
552#define HOOK_ACTIVE 0x10
553#define HOOK_ACTIVE_SHIFT 4
554#define HOOK_VMEVENT 0x20
555#define HOOK_GC 0x40
556#define hook_active(g) ((g)->hookmask & HOOK_ACTIVE)
557#define hook_enter(g) ((g)->hookmask |= HOOK_ACTIVE)
558#define hook_entergc(g) ((g)->hookmask |= (HOOK_ACTIVE|HOOK_GC))
559#define hook_vmevent(g) ((g)->hookmask |= (HOOK_ACTIVE|HOOK_VMEVENT))
560#define hook_leave(g) ((g)->hookmask &= ~HOOK_ACTIVE)
561#define hook_save(g) ((g)->hookmask & ~HOOK_EVENTMASK)
562#define hook_restore(g, h) \
563 ((g)->hookmask = ((g)->hookmask & HOOK_EVENTMASK) | (h))
564
565/* Per-thread state object. */
566struct lua_State {
567 GCHeader;
568 uint8_t dummy_ffid; /* Fake FF_C for curr_funcisL() on dummy frames. */
569 uint8_t status; /* Thread status. */
570 MRef glref; /* Link to global state. */
571 GCRef gclist; /* GC chain. */
572 TValue *base; /* Base of currently executing function. */
573 TValue *top; /* First free slot in the stack. */
574 MRef maxstack; /* Last free slot in the stack. */
575 MRef stack; /* Stack base. */
576 GCRef openupval; /* List of open upvalues in the stack. */
577 GCRef env; /* Thread environment (table of globals). */
578 void *cframe; /* End of C stack frame chain. */
579 MSize stacksize; /* True stack size (incl. LJ_STACK_EXTRA). */
580};
581
582#define G(L) (mref(L->glref, global_State))
583#define registry(L) (&G(L)->registrytv)
584
585/* Macros to access the currently executing (Lua) function. */
586#define curr_func(L) (&gcref((L->base-1)->fr.func)->fn)
587#define curr_funcisL(L) (isluafunc(curr_func(L)))
588#define curr_proto(L) (funcproto(curr_func(L)))
589#define curr_topL(L) (L->base + curr_proto(L)->framesize)
590#define curr_top(L) (curr_funcisL(L) ? curr_topL(L) : L->top)
591
592/* -- GC object definition and conversions -------------------------------- */
593
594/* GC header for generic access to common fields of GC objects. */
595typedef struct GChead {
596 GCHeader;
597 uint8_t unused1;
598 uint8_t unused2;
599 GCRef env;
600 GCRef gclist;
601 GCRef metatable;
602} GChead;
603
604/* The env field SHOULD be at the same offset for all GC objects. */
605LJ_STATIC_ASSERT(offsetof(GChead, env) == offsetof(GCfuncL, env));
606LJ_STATIC_ASSERT(offsetof(GChead, env) == offsetof(GCudata, env));
607
608/* The metatable field MUST be at the same offset for all GC objects. */
609LJ_STATIC_ASSERT(offsetof(GChead, metatable) == offsetof(GCtab, metatable));
610LJ_STATIC_ASSERT(offsetof(GChead, metatable) == offsetof(GCudata, metatable));
611
612/* The gclist field MUST be at the same offset for all GC objects. */
613LJ_STATIC_ASSERT(offsetof(GChead, gclist) == offsetof(lua_State, gclist));
614LJ_STATIC_ASSERT(offsetof(GChead, gclist) == offsetof(GCproto, gclist));
615LJ_STATIC_ASSERT(offsetof(GChead, gclist) == offsetof(GCfuncL, gclist));
616LJ_STATIC_ASSERT(offsetof(GChead, gclist) == offsetof(GCtab, gclist));
617
618typedef union GCobj {
619 GChead gch;
620 GCstr str;
621 GCupval uv;
622 lua_State th;
623 GCproto pt;
624 GCfunc fn;
625 GCcdata cd;
626 GCtab tab;
627 GCudata ud;
628} GCobj;
629
630/* Macros to convert a GCobj pointer into a specific value. */
631#define gco2str(o) check_exp((o)->gch.gct == ~LJ_TSTR, &(o)->str)
632#define gco2uv(o) check_exp((o)->gch.gct == ~LJ_TUPVAL, &(o)->uv)
633#define gco2th(o) check_exp((o)->gch.gct == ~LJ_TTHREAD, &(o)->th)
634#define gco2pt(o) check_exp((o)->gch.gct == ~LJ_TPROTO, &(o)->pt)
635#define gco2func(o) check_exp((o)->gch.gct == ~LJ_TFUNC, &(o)->fn)
636#define gco2cd(o) check_exp((o)->gch.gct == ~LJ_TCDATA, &(o)->cd)
637#define gco2tab(o) check_exp((o)->gch.gct == ~LJ_TTAB, &(o)->tab)
638#define gco2ud(o) check_exp((o)->gch.gct == ~LJ_TUDATA, &(o)->ud)
639
640/* Macro to convert any collectable object into a GCobj pointer. */
641#define obj2gco(v) ((GCobj *)(v))
642
643/* -- TValue getters/setters ---------------------------------------------- */
644
645#ifdef LUA_USE_ASSERT
646#include "lj_gc.h"
647#endif
648
649/* Macros to test types. */
650#define itype(o) ((o)->it)
651#define tvisnil(o) (itype(o) == LJ_TNIL)
652#define tvisfalse(o) (itype(o) == LJ_TFALSE)
653#define tvistrue(o) (itype(o) == LJ_TTRUE)
654#define tvisbool(o) (tvisfalse(o) || tvistrue(o))
655#if LJ_64
656#define tvislightud(o) (((int32_t)itype(o) >> 15) == -2)
657#else
658#define tvislightud(o) (itype(o) == LJ_TLIGHTUD)
659#endif
660#define tvisstr(o) (itype(o) == LJ_TSTR)
661#define tvisfunc(o) (itype(o) == LJ_TFUNC)
662#define tvisthread(o) (itype(o) == LJ_TTHREAD)
663#define tvisproto(o) (itype(o) == LJ_TPROTO)
664#define tviscdata(o) (itype(o) == LJ_TCDATA)
665#define tvistab(o) (itype(o) == LJ_TTAB)
666#define tvisudata(o) (itype(o) == LJ_TUDATA)
667#define tvisnumber(o) (itype(o) <= LJ_TISNUM)
668#define tvisint(o) (LJ_DUALNUM && itype(o) == LJ_TISNUM)
669#define tvisnum(o) (itype(o) < LJ_TISNUM)
670
671#define tvistruecond(o) (itype(o) < LJ_TISTRUECOND)
672#define tvispri(o) (itype(o) >= LJ_TISPRI)
673#define tvistabud(o) (itype(o) <= LJ_TISTABUD) /* && !tvisnum() */
674#define tvisgcv(o) ((itype(o) - LJ_TISGCV) > (LJ_TNUMX - LJ_TISGCV))
675
676/* Special macros to test numbers for NaN, +0, -0, +1 and raw equality. */
677#define tvisnan(o) ((o)->n != (o)->n)
678#if LJ_64
679#define tviszero(o) (((o)->u64 << 1) == 0)
680#else
681#define tviszero(o) (((o)->u32.lo | ((o)->u32.hi << 1)) == 0)
682#endif
683#define tvispzero(o) ((o)->u64 == 0)
684#define tvismzero(o) ((o)->u64 == U64x(80000000,00000000))
685#define tvispone(o) ((o)->u64 == U64x(3ff00000,00000000))
686#define rawnumequal(o1, o2) ((o1)->u64 == (o2)->u64)
687
688/* Macros to convert type ids. */
689#if LJ_64
690#define itypemap(o) \
691 (tvisnumber(o) ? ~LJ_TNUMX : tvislightud(o) ? ~LJ_TLIGHTUD : ~itype(o))
692#else
693#define itypemap(o) (tvisnumber(o) ? ~LJ_TNUMX : ~itype(o))
694#endif
695
696/* Macros to get tagged values. */
697#define gcval(o) (gcref((o)->gcr))
698#define boolV(o) check_exp(tvisbool(o), (LJ_TFALSE - (o)->it))
699#if LJ_64
700#define lightudV(o) \
701 check_exp(tvislightud(o), (void *)((o)->u64 & U64x(00007fff,ffffffff)))
702#else
703#define lightudV(o) check_exp(tvislightud(o), gcrefp((o)->gcr, void))
704#endif
705#define gcV(o) check_exp(tvisgcv(o), gcval(o))
706#define strV(o) check_exp(tvisstr(o), &gcval(o)->str)
707#define funcV(o) check_exp(tvisfunc(o), &gcval(o)->fn)
708#define threadV(o) check_exp(tvisthread(o), &gcval(o)->th)
709#define protoV(o) check_exp(tvisproto(o), &gcval(o)->pt)
710#define cdataV(o) check_exp(tviscdata(o), &gcval(o)->cd)
711#define tabV(o) check_exp(tvistab(o), &gcval(o)->tab)
712#define udataV(o) check_exp(tvisudata(o), &gcval(o)->ud)
713#define numV(o) check_exp(tvisnum(o), (o)->n)
714#define intV(o) check_exp(tvisint(o), (int32_t)(o)->i)
715
716/* Macros to set tagged values. */
717#define setitype(o, i) ((o)->it = (i))
718#define setnilV(o) ((o)->it = LJ_TNIL)
719#define setboolV(o, x) ((o)->it = LJ_TFALSE-(uint32_t)(x))
720
721static LJ_AINLINE void setlightudV(TValue *o, void *p)
722{
723#if LJ_64
724 o->u64 = (uint64_t)p | (((uint64_t)0xffff) << 48);
725#else
726 setgcrefp(o->gcr, p); setitype(o, LJ_TLIGHTUD);
727#endif
728}
729
730#if LJ_64
731#define checklightudptr(L, p) \
732 (((uint64_t)(p) >> 47) ? (lj_err_msg(L, LJ_ERR_BADLU), NULL) : (p))
733#define setcont(o, f) \
734 ((o)->u64 = (uint64_t)(void *)(f) - (uint64_t)lj_vm_asm_begin)
735#else
736#define checklightudptr(L, p) (p)
737#define setcont(o, f) setlightudV((o), (void *)(f))
738#endif
739
740#define tvchecklive(L, o) \
741 UNUSED(L), lua_assert(!tvisgcv(o) || \
742 ((~itype(o) == gcval(o)->gch.gct) && !isdead(G(L), gcval(o))))
743
744static LJ_AINLINE void setgcV(lua_State *L, TValue *o, GCobj *v, uint32_t itype)
745{
746 setgcref(o->gcr, v); setitype(o, itype); tvchecklive(L, o);
747}
748
749#define define_setV(name, type, tag) \
750static LJ_AINLINE void name(lua_State *L, TValue *o, type *v) \
751{ \
752 setgcV(L, o, obj2gco(v), tag); \
753}
754define_setV(setstrV, GCstr, LJ_TSTR)
755define_setV(setthreadV, lua_State, LJ_TTHREAD)
756define_setV(setprotoV, GCproto, LJ_TPROTO)
757define_setV(setfuncV, GCfunc, LJ_TFUNC)
758define_setV(setcdataV, GCcdata, LJ_TCDATA)
759define_setV(settabV, GCtab, LJ_TTAB)
760define_setV(setudataV, GCudata, LJ_TUDATA)
761
762#define setnumV(o, x) ((o)->n = (x))
763#define setnanV(o) ((o)->u64 = U64x(fff80000,00000000))
764#define setpinfV(o) ((o)->u64 = U64x(7ff00000,00000000))
765#define setminfV(o) ((o)->u64 = U64x(fff00000,00000000))
766
767static LJ_AINLINE void setintV(TValue *o, int32_t i)
768{
769#if LJ_DUALNUM
770 o->i = (uint32_t)i; setitype(o, LJ_TISNUM);
771#else
772 o->n = (lua_Number)i;
773#endif
774}
775
776static LJ_AINLINE void setint64V(TValue *o, int64_t i)
777{
778 if (LJ_DUALNUM && LJ_LIKELY(i == (int64_t)(int32_t)i))
779 setintV(o, (int32_t)i);
780 else
781 setnumV(o, (lua_Number)i);
782}
783
784#if LJ_64
785#define setintptrV(o, i) setint64V((o), (i))
786#else
787#define setintptrV(o, i) setintV((o), (i))
788#endif
789
790/* Copy tagged values. */
791static LJ_AINLINE void copyTV(lua_State *L, TValue *o1, const TValue *o2)
792{
793 *o1 = *o2; tvchecklive(L, o1);
794}
795
796/* -- Number to integer conversion ---------------------------------------- */
797
798#if LJ_SOFTFP
799LJ_ASMF int32_t lj_vm_tobit(double x);
800#endif
801
802static LJ_AINLINE int32_t lj_num2bit(lua_Number n)
803{
804#if LJ_SOFTFP
805 return lj_vm_tobit(n);
806#else
807 TValue o;
808 o.n = n + 6755399441055744.0; /* 2^52 + 2^51 */
809 return (int32_t)o.u32.lo;
810#endif
811}
812
813#if LJ_TARGET_X86 && !defined(__SSE2__)
814#define lj_num2int(n) lj_num2bit((n))
815#else
816#define lj_num2int(n) ((int32_t)(n))
817#endif
818
819static LJ_AINLINE uint64_t lj_num2u64(lua_Number n)
820{
821#ifdef _MSC_VER
822 if (n >= 9223372036854775808.0) /* They think it's a feature. */
823 return (uint64_t)(int64_t)(n - 18446744073709551616.0);
824 else
825#endif
826 return (uint64_t)n;
827}
828
829static LJ_AINLINE int32_t numberVint(cTValue *o)
830{
831 if (LJ_LIKELY(tvisint(o)))
832 return intV(o);
833 else
834 return lj_num2int(numV(o));
835}
836
837static LJ_AINLINE lua_Number numberVnum(cTValue *o)
838{
839 if (LJ_UNLIKELY(tvisint(o)))
840 return (lua_Number)intV(o);
841 else
842 return numV(o);
843}
844
845/* -- Miscellaneous object handling --------------------------------------- */
846
847/* Names and maps for internal and external object tags. */
848LJ_DATA const char *const lj_obj_typename[1+LUA_TCDATA+1];
849LJ_DATA const char *const lj_obj_itypename[~LJ_TNUMX+1];
850
851#define lj_typename(o) (lj_obj_itypename[itypemap(o)])
852
853/* Compare two objects without calling metamethods. */
854LJ_FUNC int lj_obj_equal(cTValue *o1, cTValue *o2);
855
856#endif
857