1/*
2** $Id: lopcodes.h $
3** Opcodes for Lua virtual machine
4** See Copyright Notice in lua.h
5*/
6
7#ifndef lopcodes_h
8#define lopcodes_h
9
10#include "llimits.h"
11
12
13/*===========================================================================
14 We assume that instructions are unsigned 32-bit integers.
15 All instructions have an opcode in the first 7 bits.
16 Instructions can have the following formats:
17
18 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0
19 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
20iABC C(8) | B(8) |k| A(8) | Op(7) |
21iABx Bx(17) | A(8) | Op(7) |
22iAsBx sBx (signed)(17) | A(8) | Op(7) |
23iAx Ax(25) | Op(7) |
24isJ sJ (signed)(25) | Op(7) |
25
26 A signed argument is represented in excess K: the represented value is
27 the written unsigned value minus K, where K is half the maximum for the
28 corresponding unsigned argument.
29===========================================================================*/
30
31
32enum OpMode {iABC, iABx, iAsBx, iAx, isJ}; /* basic instruction formats */
33
34
35/*
36** size and position of opcode arguments.
37*/
38#define SIZE_C 8
39#define SIZE_B 8
40#define SIZE_Bx (SIZE_C + SIZE_B + 1)
41#define SIZE_A 8
42#define SIZE_Ax (SIZE_Bx + SIZE_A)
43#define SIZE_sJ (SIZE_Bx + SIZE_A)
44
45#define SIZE_OP 7
46
47#define POS_OP 0
48
49#define POS_A (POS_OP + SIZE_OP)
50#define POS_k (POS_A + SIZE_A)
51#define POS_B (POS_k + 1)
52#define POS_C (POS_B + SIZE_B)
53
54#define POS_Bx POS_k
55
56#define POS_Ax POS_A
57
58#define POS_sJ POS_A
59
60
61/*
62** limits for opcode arguments.
63** we use (signed) 'int' to manipulate most arguments,
64** so they must fit in ints.
65*/
66
67/* Check whether type 'int' has at least 'b' bits ('b' < 32) */
68#define L_INTHASBITS(b) ((UINT_MAX >> ((b) - 1)) >= 1)
69
70
71#if L_INTHASBITS(SIZE_Bx)
72#define MAXARG_Bx ((1<<SIZE_Bx)-1)
73#else
74#define MAXARG_Bx MAX_INT
75#endif
76
77#define OFFSET_sBx (MAXARG_Bx>>1) /* 'sBx' is signed */
78
79
80#if L_INTHASBITS(SIZE_Ax)
81#define MAXARG_Ax ((1<<SIZE_Ax)-1)
82#else
83#define MAXARG_Ax MAX_INT
84#endif
85
86#if L_INTHASBITS(SIZE_sJ)
87#define MAXARG_sJ ((1 << SIZE_sJ) - 1)
88#else
89#define MAXARG_sJ MAX_INT
90#endif
91
92#define OFFSET_sJ (MAXARG_sJ >> 1)
93
94
95#define MAXARG_A ((1<<SIZE_A)-1)
96#define MAXARG_B ((1<<SIZE_B)-1)
97#define MAXARG_C ((1<<SIZE_C)-1)
98#define OFFSET_sC (MAXARG_C >> 1)
99
100#define int2sC(i) ((i) + OFFSET_sC)
101#define sC2int(i) ((i) - OFFSET_sC)
102
103
104/* creates a mask with 'n' 1 bits at position 'p' */
105#define MASK1(n,p) ((~((~(Instruction)0)<<(n)))<<(p))
106
107/* creates a mask with 'n' 0 bits at position 'p' */
108#define MASK0(n,p) (~MASK1(n,p))
109
110/*
111** the following macros help to manipulate instructions
112*/
113
114#define GET_OPCODE(i) (cast(OpCode, ((i)>>POS_OP) & MASK1(SIZE_OP,0)))
115#define SET_OPCODE(i,o) ((i) = (((i)&MASK0(SIZE_OP,POS_OP)) | \
116 ((cast(Instruction, o)<<POS_OP)&MASK1(SIZE_OP,POS_OP))))
117
118#define checkopm(i,m) (getOpMode(GET_OPCODE(i)) == m)
119
120
121#define getarg(i,pos,size) (cast_int(((i)>>(pos)) & MASK1(size,0)))
122#define setarg(i,v,pos,size) ((i) = (((i)&MASK0(size,pos)) | \
123 ((cast(Instruction, v)<<pos)&MASK1(size,pos))))
124
125#define GETARG_A(i) getarg(i, POS_A, SIZE_A)
126#define SETARG_A(i,v) setarg(i, v, POS_A, SIZE_A)
127
128#define GETARG_B(i) check_exp(checkopm(i, iABC), getarg(i, POS_B, SIZE_B))
129#define GETARG_sB(i) sC2int(GETARG_B(i))
130#define SETARG_B(i,v) setarg(i, v, POS_B, SIZE_B)
131
132#define GETARG_C(i) check_exp(checkopm(i, iABC), getarg(i, POS_C, SIZE_C))
133#define GETARG_sC(i) sC2int(GETARG_C(i))
134#define SETARG_C(i,v) setarg(i, v, POS_C, SIZE_C)
135
136#define TESTARG_k(i) check_exp(checkopm(i, iABC), (cast_int(((i) & (1u << POS_k)))))
137#define GETARG_k(i) check_exp(checkopm(i, iABC), getarg(i, POS_k, 1))
138#define SETARG_k(i,v) setarg(i, v, POS_k, 1)
139
140#define GETARG_Bx(i) check_exp(checkopm(i, iABx), getarg(i, POS_Bx, SIZE_Bx))
141#define SETARG_Bx(i,v) setarg(i, v, POS_Bx, SIZE_Bx)
142
143#define GETARG_Ax(i) check_exp(checkopm(i, iAx), getarg(i, POS_Ax, SIZE_Ax))
144#define SETARG_Ax(i,v) setarg(i, v, POS_Ax, SIZE_Ax)
145
146#define GETARG_sBx(i) \
147 check_exp(checkopm(i, iAsBx), getarg(i, POS_Bx, SIZE_Bx) - OFFSET_sBx)
148#define SETARG_sBx(i,b) SETARG_Bx((i),cast_uint((b)+OFFSET_sBx))
149
150#define GETARG_sJ(i) \
151 check_exp(checkopm(i, isJ), getarg(i, POS_sJ, SIZE_sJ) - OFFSET_sJ)
152#define SETARG_sJ(i,j) \
153 setarg(i, cast_uint((j)+OFFSET_sJ), POS_sJ, SIZE_sJ)
154
155
156#define CREATE_ABCk(o,a,b,c,k) ((cast(Instruction, o)<<POS_OP) \
157 | (cast(Instruction, a)<<POS_A) \
158 | (cast(Instruction, b)<<POS_B) \
159 | (cast(Instruction, c)<<POS_C) \
160 | (cast(Instruction, k)<<POS_k))
161
162#define CREATE_ABx(o,a,bc) ((cast(Instruction, o)<<POS_OP) \
163 | (cast(Instruction, a)<<POS_A) \
164 | (cast(Instruction, bc)<<POS_Bx))
165
166#define CREATE_Ax(o,a) ((cast(Instruction, o)<<POS_OP) \
167 | (cast(Instruction, a)<<POS_Ax))
168
169#define CREATE_sJ(o,j,k) ((cast(Instruction, o) << POS_OP) \
170 | (cast(Instruction, j) << POS_sJ) \
171 | (cast(Instruction, k) << POS_k))
172
173
174#if !defined(MAXINDEXRK) /* (for debugging only) */
175#define MAXINDEXRK MAXARG_B
176#endif
177
178
179/*
180** invalid register that fits in 8 bits
181*/
182#define NO_REG MAXARG_A
183
184
185/*
186** R[x] - register
187** K[x] - constant (in constant table)
188** RK(x) == if k(i) then K[x] else R[x]
189*/
190
191
192/*
193** Grep "ORDER OP" if you change these enums. Opcodes marked with a (*)
194** has extra descriptions in the notes after the enumeration.
195*/
196
197typedef enum {
198/*----------------------------------------------------------------------
199 name args description
200------------------------------------------------------------------------*/
201OP_MOVE,/* A B R[A] := R[B] */
202OP_LOADI,/* A sBx R[A] := sBx */
203OP_LOADF,/* A sBx R[A] := (lua_Number)sBx */
204OP_LOADK,/* A Bx R[A] := K[Bx] */
205OP_LOADKX,/* A R[A] := K[extra arg] */
206OP_LOADFALSE,/* A R[A] := false */
207OP_LFALSESKIP,/*A R[A] := false; pc++ (*) */
208OP_LOADTRUE,/* A R[A] := true */
209OP_LOADNIL,/* A B R[A], R[A+1], ..., R[A+B] := nil */
210OP_GETUPVAL,/* A B R[A] := UpValue[B] */
211OP_SETUPVAL,/* A B UpValue[B] := R[A] */
212
213OP_GETTABUP,/* A B C R[A] := UpValue[B][K[C]:shortstring] */
214OP_GETTABLE,/* A B C R[A] := R[B][R[C]] */
215OP_GETI,/* A B C R[A] := R[B][C] */
216OP_GETFIELD,/* A B C R[A] := R[B][K[C]:shortstring] */
217
218OP_SETTABUP,/* A B C UpValue[A][K[B]:shortstring] := RK(C) */
219OP_SETTABLE,/* A B C R[A][R[B]] := RK(C) */
220OP_SETI,/* A B C R[A][B] := RK(C) */
221OP_SETFIELD,/* A B C R[A][K[B]:shortstring] := RK(C) */
222
223OP_NEWTABLE,/* A B C k R[A] := {} */
224
225OP_SELF,/* A B C R[A+1] := R[B]; R[A] := R[B][RK(C):string] */
226
227OP_ADDI,/* A B sC R[A] := R[B] + sC */
228
229OP_ADDK,/* A B C R[A] := R[B] + K[C]:number */
230OP_SUBK,/* A B C R[A] := R[B] - K[C]:number */
231OP_MULK,/* A B C R[A] := R[B] * K[C]:number */
232OP_MODK,/* A B C R[A] := R[B] % K[C]:number */
233OP_POWK,/* A B C R[A] := R[B] ^ K[C]:number */
234OP_DIVK,/* A B C R[A] := R[B] / K[C]:number */
235OP_IDIVK,/* A B C R[A] := R[B] // K[C]:number */
236
237OP_BANDK,/* A B C R[A] := R[B] & K[C]:integer */
238OP_BORK,/* A B C R[A] := R[B] | K[C]:integer */
239OP_BXORK,/* A B C R[A] := R[B] ~ K[C]:integer */
240
241OP_SHRI,/* A B sC R[A] := R[B] >> sC */
242OP_SHLI,/* A B sC R[A] := sC << R[B] */
243
244OP_ADD,/* A B C R[A] := R[B] + R[C] */
245OP_SUB,/* A B C R[A] := R[B] - R[C] */
246OP_MUL,/* A B C R[A] := R[B] * R[C] */
247OP_MOD,/* A B C R[A] := R[B] % R[C] */
248OP_POW,/* A B C R[A] := R[B] ^ R[C] */
249OP_DIV,/* A B C R[A] := R[B] / R[C] */
250OP_IDIV,/* A B C R[A] := R[B] // R[C] */
251
252OP_BAND,/* A B C R[A] := R[B] & R[C] */
253OP_BOR,/* A B C R[A] := R[B] | R[C] */
254OP_BXOR,/* A B C R[A] := R[B] ~ R[C] */
255OP_SHL,/* A B C R[A] := R[B] << R[C] */
256OP_SHR,/* A B C R[A] := R[B] >> R[C] */
257
258OP_MMBIN,/* A B C call C metamethod over R[A] and R[B] (*) */
259OP_MMBINI,/* A sB C k call C metamethod over R[A] and sB */
260OP_MMBINK,/* A B C k call C metamethod over R[A] and K[B] */
261
262OP_UNM,/* A B R[A] := -R[B] */
263OP_BNOT,/* A B R[A] := ~R[B] */
264OP_NOT,/* A B R[A] := not R[B] */
265OP_LEN,/* A B R[A] := #R[B] (length operator) */
266
267OP_CONCAT,/* A B R[A] := R[A].. ... ..R[A + B - 1] */
268
269OP_CLOSE,/* A close all upvalues >= R[A] */
270OP_TBC,/* A mark variable A "to be closed" */
271OP_JMP,/* sJ pc += sJ */
272OP_EQ,/* A B k if ((R[A] == R[B]) ~= k) then pc++ */
273OP_LT,/* A B k if ((R[A] < R[B]) ~= k) then pc++ */
274OP_LE,/* A B k if ((R[A] <= R[B]) ~= k) then pc++ */
275
276OP_EQK,/* A B k if ((R[A] == K[B]) ~= k) then pc++ */
277OP_EQI,/* A sB k if ((R[A] == sB) ~= k) then pc++ */
278OP_LTI,/* A sB k if ((R[A] < sB) ~= k) then pc++ */
279OP_LEI,/* A sB k if ((R[A] <= sB) ~= k) then pc++ */
280OP_GTI,/* A sB k if ((R[A] > sB) ~= k) then pc++ */
281OP_GEI,/* A sB k if ((R[A] >= sB) ~= k) then pc++ */
282
283OP_TEST,/* A k if (not R[A] == k) then pc++ */
284OP_TESTSET,/* A B k if (not R[B] == k) then pc++ else R[A] := R[B] (*) */
285
286OP_CALL,/* A B C R[A], ... ,R[A+C-2] := R[A](R[A+1], ... ,R[A+B-1]) */
287OP_TAILCALL,/* A B C k return R[A](R[A+1], ... ,R[A+B-1]) */
288
289OP_RETURN,/* A B C k return R[A], ... ,R[A+B-2] (see note) */
290OP_RETURN0,/* return */
291OP_RETURN1,/* A return R[A] */
292
293OP_FORLOOP,/* A Bx update counters; if loop continues then pc-=Bx; */
294OP_FORPREP,/* A Bx <check values and prepare counters>;
295 if not to run then pc+=Bx+1; */
296
297OP_TFORPREP,/* A Bx create upvalue for R[A + 3]; pc+=Bx */
298OP_TFORCALL,/* A C R[A+4], ... ,R[A+3+C] := R[A](R[A+1], R[A+2]); */
299OP_TFORLOOP,/* A Bx if R[A+2] ~= nil then { R[A]=R[A+2]; pc -= Bx } */
300
301OP_SETLIST,/* A B C k R[A][C+i] := R[A+i], 1 <= i <= B */
302
303OP_CLOSURE,/* A Bx R[A] := closure(KPROTO[Bx]) */
304
305OP_VARARG,/* A C R[A], R[A+1], ..., R[A+C-2] = vararg */
306
307OP_VARARGPREP,/*A (adjust vararg parameters) */
308
309OP_EXTRAARG/* Ax extra (larger) argument for previous opcode */
310} OpCode;
311
312
313#define NUM_OPCODES ((int)(OP_EXTRAARG) + 1)
314
315
316
317/*===========================================================================
318 Notes:
319
320 (*) Opcode OP_LFALSESKIP is used to convert a condition to a boolean
321 value, in a code equivalent to (not cond ? false : true). (It
322 produces false and skips the next instruction producing true.)
323
324 (*) Opcodes OP_MMBIN and variants follow each arithmetic and
325 bitwise opcode. If the operation succeeds, it skips this next
326 opcode. Otherwise, this opcode calls the corresponding metamethod.
327
328 (*) Opcode OP_TESTSET is used in short-circuit expressions that need
329 both to jump and to produce a value, such as (a = b or c).
330
331 (*) In OP_CALL, if (B == 0) then B = top - A. If (C == 0), then
332 'top' is set to last_result+1, so next open instruction (OP_CALL,
333 OP_RETURN*, OP_SETLIST) may use 'top'.
334
335 (*) In OP_VARARG, if (C == 0) then use actual number of varargs and
336 set top (like in OP_CALL with C == 0).
337
338 (*) In OP_RETURN, if (B == 0) then return up to 'top'.
339
340 (*) In OP_LOADKX and OP_NEWTABLE, the next instruction is always
341 OP_EXTRAARG.
342
343 (*) In OP_SETLIST, if (B == 0) then real B = 'top'; if k, then
344 real C = EXTRAARG _ C (the bits of EXTRAARG concatenated with the
345 bits of C).
346
347 (*) In OP_NEWTABLE, B is log2 of the hash size (which is always a
348 power of 2) plus 1, or zero for size zero. If not k, the array size
349 is C. Otherwise, the array size is EXTRAARG _ C.
350
351 (*) For comparisons, k specifies what condition the test should accept
352 (true or false).
353
354 (*) In OP_MMBINI/OP_MMBINK, k means the arguments were flipped
355 (the constant is the first operand).
356
357 (*) All 'skips' (pc++) assume that next instruction is a jump.
358
359 (*) In instructions OP_RETURN/OP_TAILCALL, 'k' specifies that the
360 function builds upvalues, which may need to be closed. C > 0 means
361 the function is vararg, so that its 'func' must be corrected before
362 returning; in this case, (C - 1) is its number of fixed parameters.
363
364 (*) In comparisons with an immediate operand, C signals whether the
365 original operand was a float. (It must be corrected in case of
366 metamethods.)
367
368===========================================================================*/
369
370
371/*
372** masks for instruction properties. The format is:
373** bits 0-2: op mode
374** bit 3: instruction set register A
375** bit 4: operator is a test (next instruction must be a jump)
376** bit 5: instruction uses 'L->top' set by previous instruction (when B == 0)
377** bit 6: instruction sets 'L->top' for next instruction (when C == 0)
378** bit 7: instruction is an MM instruction (call a metamethod)
379*/
380
381LUAI_DDEC(const lu_byte luaP_opmodes[NUM_OPCODES];)
382
383#define getOpMode(m) (cast(enum OpMode, luaP_opmodes[m] & 7))
384#define testAMode(m) (luaP_opmodes[m] & (1 << 3))
385#define testTMode(m) (luaP_opmodes[m] & (1 << 4))
386#define testITMode(m) (luaP_opmodes[m] & (1 << 5))
387#define testOTMode(m) (luaP_opmodes[m] & (1 << 6))
388#define testMMMode(m) (luaP_opmodes[m] & (1 << 7))
389
390/* "out top" (set top for next instruction) */
391#define isOT(i) \
392 ((testOTMode(GET_OPCODE(i)) && GETARG_C(i) == 0) || \
393 GET_OPCODE(i) == OP_TAILCALL)
394
395/* "in top" (uses top from previous instruction) */
396#define isIT(i) (testITMode(GET_OPCODE(i)) && GETARG_B(i) == 0)
397
398#define opmode(mm,ot,it,t,a,m) \
399 (((mm) << 7) | ((ot) << 6) | ((it) << 5) | ((t) << 4) | ((a) << 3) | (m))
400
401
402/* number of list items to accumulate before a SETLIST instruction */
403#define LFIELDS_PER_FLUSH 50
404
405#endif