The Battle for Wesnoth  1.17.0-dev
lopcodes.h
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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
20 iABC C(8) | B(8) |k| A(8) | Op(7) |
21 iABx Bx(17) | A(8) | Op(7) |
22 iAsBx sBx (signed)(17) | A(8) | Op(7) |
23 iAx Ax(25) | Op(7) |
24 isJ sJ(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 
32 enum 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
194 */
195 
196 typedef enum {
197 /*----------------------------------------------------------------------
198  name args description
199 ------------------------------------------------------------------------*/
200 OP_MOVE,/* A B R[A] := R[B] */
201 OP_LOADI,/* A sBx R[A] := sBx */
202 OP_LOADF,/* A sBx R[A] := (lua_Number)sBx */
203 OP_LOADK,/* A Bx R[A] := K[Bx] */
204 OP_LOADKX,/* A R[A] := K[extra arg] */
205 OP_LOADFALSE,/* A R[A] := false */
206 OP_LFALSESKIP,/*A R[A] := false; pc++ */
207 OP_LOADTRUE,/* A R[A] := true */
208 OP_LOADNIL,/* A B R[A], R[A+1], ..., R[A+B] := nil */
209 OP_GETUPVAL,/* A B R[A] := UpValue[B] */
210 OP_SETUPVAL,/* A B UpValue[B] := R[A] */
211 
212 OP_GETTABUP,/* A B C R[A] := UpValue[B][K[C]:string] */
213 OP_GETTABLE,/* A B C R[A] := R[B][R[C]] */
214 OP_GETI,/* A B C R[A] := R[B][C] */
215 OP_GETFIELD,/* A B C R[A] := R[B][K[C]:string] */
216 
217 OP_SETTABUP,/* A B C UpValue[A][K[B]:string] := RK(C) */
218 OP_SETTABLE,/* A B C R[A][R[B]] := RK(C) */
219 OP_SETI,/* A B C R[A][B] := RK(C) */
220 OP_SETFIELD,/* A B C R[A][K[B]:string] := RK(C) */
221 
222 OP_NEWTABLE,/* A B C k R[A] := {} */
223 
224 OP_SELF,/* A B C R[A+1] := R[B]; R[A] := R[B][RK(C):string] */
225 
226 OP_ADDI,/* A B sC R[A] := R[B] + sC */
227 
228 OP_ADDK,/* A B C R[A] := R[B] + K[C] */
229 OP_SUBK,/* A B C R[A] := R[B] - K[C] */
230 OP_MULK,/* A B C R[A] := R[B] * K[C] */
231 OP_MODK,/* A B C R[A] := R[B] % K[C] */
232 OP_POWK,/* A B C R[A] := R[B] ^ K[C] */
233 OP_DIVK,/* A B C R[A] := R[B] / K[C] */
234 OP_IDIVK,/* A B C R[A] := R[B] // K[C] */
235 
236 OP_BANDK,/* A B C R[A] := R[B] & K[C]:integer */
237 OP_BORK,/* A B C R[A] := R[B] | K[C]:integer */
238 OP_BXORK,/* A B C R[A] := R[B] ~ K[C]:integer */
239 
240 OP_SHRI,/* A B sC R[A] := R[B] >> sC */
241 OP_SHLI,/* A B sC R[A] := sC << R[B] */
242 
243 OP_ADD,/* A B C R[A] := R[B] + R[C] */
244 OP_SUB,/* A B C R[A] := R[B] - R[C] */
245 OP_MUL,/* A B C R[A] := R[B] * R[C] */
246 OP_MOD,/* A B C R[A] := R[B] % R[C] */
247 OP_POW,/* A B C R[A] := R[B] ^ R[C] */
248 OP_DIV,/* A B C R[A] := R[B] / R[C] */
249 OP_IDIV,/* A B C R[A] := R[B] // R[C] */
250 
251 OP_BAND,/* A B C R[A] := R[B] & R[C] */
252 OP_BOR,/* A B C R[A] := R[B] | R[C] */
253 OP_BXOR,/* A B C R[A] := R[B] ~ R[C] */
254 OP_SHL,/* A B C R[A] := R[B] << R[C] */
255 OP_SHR,/* A B C R[A] := R[B] >> R[C] */
256 
257 OP_MMBIN,/* A B C call C metamethod over R[A] and R[B] */
258 OP_MMBINI,/* A sB C k call C metamethod over R[A] and sB */
259 OP_MMBINK,/* A B C k call C metamethod over R[A] and K[B] */
260 
261 OP_UNM,/* A B R[A] := -R[B] */
262 OP_BNOT,/* A B R[A] := ~R[B] */
263 OP_NOT,/* A B R[A] := not R[B] */
264 OP_LEN,/* A B R[A] := #R[B] (length operator) */
265 
266 OP_CONCAT,/* A B R[A] := R[A].. ... ..R[A + B - 1] */
267 
268 OP_CLOSE,/* A close all upvalues >= R[A] */
269 OP_TBC,/* A mark variable A "to be closed" */
270 OP_JMP,/* sJ pc += sJ */
271 OP_EQ,/* A B k if ((R[A] == R[B]) ~= k) then pc++ */
272 OP_LT,/* A B k if ((R[A] < R[B]) ~= k) then pc++ */
273 OP_LE,/* A B k if ((R[A] <= R[B]) ~= k) then pc++ */
274 
275 OP_EQK,/* A B k if ((R[A] == K[B]) ~= k) then pc++ */
276 OP_EQI,/* A sB k if ((R[A] == sB) ~= k) then pc++ */
277 OP_LTI,/* A sB k if ((R[A] < sB) ~= k) then pc++ */
278 OP_LEI,/* A sB k if ((R[A] <= sB) ~= k) then pc++ */
279 OP_GTI,/* A sB k if ((R[A] > sB) ~= k) then pc++ */
280 OP_GEI,/* A sB k if ((R[A] >= sB) ~= k) then pc++ */
281 
282 OP_TEST,/* A k if (not R[A] == k) then pc++ */
283 OP_TESTSET,/* A B k if (not R[B] == k) then pc++ else R[A] := R[B] */
284 
285 OP_CALL,/* A B C R[A], ... ,R[A+C-2] := R[A](R[A+1], ... ,R[A+B-1]) */
286 OP_TAILCALL,/* A B C k return R[A](R[A+1], ... ,R[A+B-1]) */
287 
288 OP_RETURN,/* A B C k return R[A], ... ,R[A+B-2] (see note) */
289 OP_RETURN0,/* return */
290 OP_RETURN1,/* A return R[A] */
291 
292 OP_FORLOOP,/* A Bx update counters; if loop continues then pc-=Bx; */
293 OP_FORPREP,/* A Bx <check values and prepare counters>;
294  if not to run then pc+=Bx+1; */
295 
296 OP_TFORPREP,/* A Bx create upvalue for R[A + 3]; pc+=Bx */
297 OP_TFORCALL,/* A C R[A+4], ... ,R[A+3+C] := R[A](R[A+1], R[A+2]); */
298 OP_TFORLOOP,/* A Bx if R[A+2] ~= nil then { R[A]=R[A+2]; pc -= Bx } */
299 
300 OP_SETLIST,/* A B C k R[A][C+i] := R[A+i], 1 <= i <= B */
301 
302 OP_CLOSURE,/* A Bx R[A] := closure(KPROTO[Bx]) */
303 
304 OP_VARARG,/* A C R[A], R[A+1], ..., R[A+C-2] = vararg */
305 
306 OP_VARARGPREP,/*A (adjust vararg parameters) */
307 
308 OP_EXTRAARG/* Ax extra (larger) argument for previous opcode */
309 } OpCode;
310 
311 
312 #define NUM_OPCODES ((int)(OP_EXTRAARG) + 1)
313 
314 
315 
316 /*===========================================================================
317  Notes:
318  (*) In OP_CALL, if (B == 0) then B = top - A. If (C == 0), then
319  'top' is set to last_result+1, so next open instruction (OP_CALL,
320  OP_RETURN*, OP_SETLIST) may use 'top'.
321 
322  (*) In OP_VARARG, if (C == 0) then use actual number of varargs and
323  set top (like in OP_CALL with C == 0).
324 
325  (*) In OP_RETURN, if (B == 0) then return up to 'top'.
326 
327  (*) In OP_LOADKX and OP_NEWTABLE, the next instruction is always
328  OP_EXTRAARG.
329 
330  (*) In OP_SETLIST, if (B == 0) then real B = 'top'; if k, then
331  real C = EXTRAARG _ C (the bits of EXTRAARG concatenated with the
332  bits of C).
333 
334  (*) In OP_NEWTABLE, B is log2 of the hash size (which is always a
335  power of 2) plus 1, or zero for size zero. If not k, the array size
336  is C. Otherwise, the array size is EXTRAARG _ C.
337 
338  (*) For comparisons, k specifies what condition the test should accept
339  (true or false).
340 
341  (*) In OP_MMBINI/OP_MMBINK, k means the arguments were flipped
342  (the constant is the first operand).
343 
344  (*) All 'skips' (pc++) assume that next instruction is a jump.
345 
346  (*) In instructions OP_RETURN/OP_TAILCALL, 'k' specifies that the
347  function builds upvalues, which may need to be closed. C > 0 means
348  the function is vararg, so that its 'func' must be corrected before
349  returning; in this case, (C - 1) is its number of fixed parameters.
350 
351  (*) In comparisons with an immediate operand, C signals whether the
352  original operand was a float. (It must be corrected in case of
353  metamethods.)
354 
355 ===========================================================================*/
356 
357 
358 /*
359 ** masks for instruction properties. The format is:
360 ** bits 0-2: op mode
361 ** bit 3: instruction set register A
362 ** bit 4: operator is a test (next instruction must be a jump)
363 ** bit 5: instruction uses 'L->top' set by previous instruction (when B == 0)
364 ** bit 6: instruction sets 'L->top' for next instruction (when C == 0)
365 ** bit 7: instruction is an MM instruction (call a metamethod)
366 */
367 
369 
370 #define getOpMode(m) (cast(enum OpMode, luaP_opmodes[m] & 7))
371 #define testAMode(m) (luaP_opmodes[m] & (1 << 3))
372 #define testTMode(m) (luaP_opmodes[m] & (1 << 4))
373 #define testITMode(m) (luaP_opmodes[m] & (1 << 5))
374 #define testOTMode(m) (luaP_opmodes[m] & (1 << 6))
375 #define testMMMode(m) (luaP_opmodes[m] & (1 << 7))
376 
377 /* "out top" (set top for next instruction) */
378 #define isOT(i) \
379  ((testOTMode(GET_OPCODE(i)) && GETARG_C(i) == 0) || \
380  GET_OPCODE(i) == OP_TAILCALL)
381 
382 /* "in top" (uses top from previous instruction) */
383 #define isIT(i) (testITMode(GET_OPCODE(i)) && GETARG_B(i) == 0)
384 
385 #define opmode(mm,ot,it,t,a,m) \
386  (((mm) << 7) | ((ot) << 6) | ((it) << 5) | ((t) << 4) | ((a) << 3) | (m))
387 
388 
389 /* number of list items to accumulate before a SETLIST instruction */
390 #define LFIELDS_PER_FLUSH 50
391 
392 #endif
#define NUM_OPCODES
Definition: lopcodes.h:312
#define cast(t, exp)
Definition: llimits.h:123
LUAI_DDEF const lu_byte luaP_opmodes[NUM_OPCODES]
Definition: lopcodes.cpp:18
Definition: lopcodes.h:32
Definition: lopcodes.h:32
OpCode
Definition: lopcodes.h:196
Definition: lopcodes.h:32
Definition: lopcodes.h:32
#define testAMode(m)
Definition: lopcodes.h:371
unsigned char lu_byte
Definition: llimits.h:36
#define getOpMode(m)
Definition: lopcodes.h:370
OpMode
Definition: lopcodes.h:32
#define LUAI_DDEC(dec)
Definition: luaconf.h:310
Definition: lopcodes.h:32