1/*
2** $Id: lopcodes.h,v 1.149.1.1 2017/04/19 17:20:42 roberto Exp $
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 numbers.
15 All instructions have an opcode in the first 6 bits.
16 Instructions can have the following fields:
17 'A' : 8 bits
18 'B' : 9 bits
19 'C' : 9 bits
20 'Ax' : 26 bits ('A', 'B', and 'C' together)
21 'Bx' : 18 bits ('B' and 'C' together)
22 'sBx' : signed Bx
23
24 A signed argument is represented in excess K; that is, the number
25 value is the unsigned value minus K. K is exactly the maximum value
26 for that argument (so that -max is represented by 0, and +max is
27 represented by 2*max), which is half the maximum for the corresponding
28 unsigned argument.
29===========================================================================*/
30
31
32enum OpMode {iABC, iABx, iAsBx, iAx}; /* basic instruction format */
33
34
35/*
36** size and position of opcode arguments.
37*/
38#define SIZE_C 9
39#define SIZE_B 9
40#define SIZE_Bx (SIZE_C + SIZE_B)
41#define SIZE_A 8
42#define SIZE_Ax (SIZE_C + SIZE_B + SIZE_A)
43
44#define SIZE_OP 6
45
46#define POS_OP 0
47#define POS_A (POS_OP + SIZE_OP)
48#define POS_C (POS_A + SIZE_A)
49#define POS_B (POS_C + SIZE_C)
50#define POS_Bx POS_C
51#define POS_Ax POS_A
52
53
54/*
55** limits for opcode arguments.
56** we use (signed) int to manipulate most arguments,
57** so they must fit in LUAI_BITSINT-1 bits (-1 for sign)
58*/
59#if SIZE_Bx < LUAI_BITSINT-1
60#define MAXARG_Bx ((1<<SIZE_Bx)-1)
61#define MAXARG_sBx (MAXARG_Bx>>1) /* 'sBx' is signed */
62#else
63#define MAXARG_Bx MAX_INT
64#define MAXARG_sBx MAX_INT
65#endif
66
67#if SIZE_Ax < LUAI_BITSINT-1
68#define MAXARG_Ax ((1<<SIZE_Ax)-1)
69#else
70#define MAXARG_Ax MAX_INT
71#endif
72
73
74#define MAXARG_A ((1<<SIZE_A)-1)
75#define MAXARG_B ((1<<SIZE_B)-1)
76#define MAXARG_C ((1<<SIZE_C)-1)
77
78
79/* creates a mask with 'n' 1 bits at position 'p' */
80#define MASK1(n,p) ((~((~(Instruction)0)<<(n)))<<(p))
81
82/* creates a mask with 'n' 0 bits at position 'p' */
83#define MASK0(n,p) (~MASK1(n,p))
84
85/*
86** the following macros help to manipulate instructions
87*/
88
89#define GET_OPCODE(i) (cast(OpCode, ((i)>>POS_OP) & MASK1(SIZE_OP,0)))
90#define SET_OPCODE(i,o) ((i) = (((i)&MASK0(SIZE_OP,POS_OP)) | \
91 ((cast(Instruction, o)<<POS_OP)&MASK1(SIZE_OP,POS_OP))))
92
93#define getarg(i,pos,size) (cast(int, ((i)>>pos) & MASK1(size,0)))
94#define setarg(i,v,pos,size) ((i) = (((i)&MASK0(size,pos)) | \
95 ((cast(Instruction, v)<<pos)&MASK1(size,pos))))
96
97#define GETARG_A(i) getarg(i, POS_A, SIZE_A)
98#define SETARG_A(i,v) setarg(i, v, POS_A, SIZE_A)
99
100#define GETARG_B(i) getarg(i, POS_B, SIZE_B)
101#define SETARG_B(i,v) setarg(i, v, POS_B, SIZE_B)
102
103#define GETARG_C(i) getarg(i, POS_C, SIZE_C)
104#define SETARG_C(i,v) setarg(i, v, POS_C, SIZE_C)
105
106#define GETARG_Bx(i) getarg(i, POS_Bx, SIZE_Bx)
107#define SETARG_Bx(i,v) setarg(i, v, POS_Bx, SIZE_Bx)
108
109#define GETARG_Ax(i) getarg(i, POS_Ax, SIZE_Ax)
110#define SETARG_Ax(i,v) setarg(i, v, POS_Ax, SIZE_Ax)
111
112#define GETARG_sBx(i) (GETARG_Bx(i)-MAXARG_sBx)
113#define SETARG_sBx(i,b) SETARG_Bx((i),cast(unsigned int, (b)+MAXARG_sBx))
114
115
116#define CREATE_ABC(o,a,b,c) ((cast(Instruction, o)<<POS_OP) \
117 | (cast(Instruction, a)<<POS_A) \
118 | (cast(Instruction, b)<<POS_B) \
119 | (cast(Instruction, c)<<POS_C))
120
121#define CREATE_ABx(o,a,bc) ((cast(Instruction, o)<<POS_OP) \
122 | (cast(Instruction, a)<<POS_A) \
123 | (cast(Instruction, bc)<<POS_Bx))
124
125#define CREATE_Ax(o,a) ((cast(Instruction, o)<<POS_OP) \
126 | (cast(Instruction, a)<<POS_Ax))
127
128
129/*
130** Macros to operate RK indices
131*/
132
133/* this bit 1 means constant (0 means register) */
134#define BITRK (1 << (SIZE_B - 1))
135
136/* test whether value is a constant */
137#define ISK(x) ((x) & BITRK)
138
139/* gets the index of the constant */
140#define INDEXK(r) ((int)(r) & ~BITRK)
141
142#if !defined(MAXINDEXRK) /* (for debugging only) */
143#define MAXINDEXRK (BITRK - 1)
144#endif
145
146/* code a constant index as a RK value */
147#define RKASK(x) ((x) | BITRK)
148
149
150/*
151** invalid register that fits in 8 bits
152*/
153#define NO_REG MAXARG_A
154
155
156/*
157** R(x) - register
158** Kst(x) - constant (in constant table)
159** RK(x) == if ISK(x) then Kst(INDEXK(x)) else R(x)
160*/
161
162
163/*
164** grep "ORDER OP" if you change these enums
165*/
166
167typedef enum {
168/*----------------------------------------------------------------------
169name args description
170------------------------------------------------------------------------*/
171OP_MOVE,/* A B R(A) := R(B) */
172OP_LOADK,/* A Bx R(A) := Kst(Bx) */
173OP_LOADKX,/* A R(A) := Kst(extra arg) */
174OP_LOADBOOL,/* A B C R(A) := (Bool)B; if (C) pc++ */
175OP_LOADNIL,/* A B R(A), R(A+1), ..., R(A+B) := nil */
176OP_GETUPVAL,/* A B R(A) := UpValue[B] */
177
178OP_GETTABUP,/* A B C R(A) := UpValue[B][RK(C)] */
179OP_GETTABLE,/* A B C R(A) := R(B)[RK(C)] */
180
181OP_SETTABUP,/* A B C UpValue[A][RK(B)] := RK(C) */
182OP_SETUPVAL,/* A B UpValue[B] := R(A) */
183OP_SETTABLE,/* A B C R(A)[RK(B)] := RK(C) */
184
185OP_NEWTABLE,/* A B C R(A) := {} (size = B,C) */
186
187OP_SELF,/* A B C R(A+1) := R(B); R(A) := R(B)[RK(C)] */
188
189OP_ADD,/* A B C R(A) := RK(B) + RK(C) */
190OP_SUB,/* A B C R(A) := RK(B) - RK(C) */
191OP_MUL,/* A B C R(A) := RK(B) * RK(C) */
192OP_MOD,/* A B C R(A) := RK(B) % RK(C) */
193OP_POW,/* A B C R(A) := RK(B) ^ RK(C) */
194OP_DIV,/* A B C R(A) := RK(B) / RK(C) */
195OP_IDIV,/* A B C R(A) := RK(B) // RK(C) */
196OP_BAND,/* A B C R(A) := RK(B) & RK(C) */
197OP_BOR,/* A B C R(A) := RK(B) | RK(C) */
198OP_BXOR,/* A B C R(A) := RK(B) ~ RK(C) */
199OP_SHL,/* A B C R(A) := RK(B) << RK(C) */
200OP_SHR,/* A B C R(A) := RK(B) >> RK(C) */
201OP_UNM,/* A B R(A) := -R(B) */
202OP_BNOT,/* A B R(A) := ~R(B) */
203OP_NOT,/* A B R(A) := not R(B) */
204OP_LEN,/* A B R(A) := length of R(B) */
205
206OP_CONCAT,/* A B C R(A) := R(B).. ... ..R(C) */
207
208OP_JMP,/* A sBx pc+=sBx; if (A) close all upvalues >= R(A - 1) */
209OP_EQ,/* A B C if ((RK(B) == RK(C)) ~= A) then pc++ */
210OP_LT,/* A B C if ((RK(B) < RK(C)) ~= A) then pc++ */
211OP_LE,/* A B C if ((RK(B) <= RK(C)) ~= A) then pc++ */
212
213OP_TEST,/* A C if not (R(A) <=> C) then pc++ */
214OP_TESTSET,/* A B C if (R(B) <=> C) then R(A) := R(B) else pc++ */
215
216OP_CALL,/* A B C R(A), ... ,R(A+C-2) := R(A)(R(A+1), ... ,R(A+B-1)) */
217OP_TAILCALL,/* A B C return R(A)(R(A+1), ... ,R(A+B-1)) */
218OP_RETURN,/* A B return R(A), ... ,R(A+B-2) (see note) */
219
220OP_FORLOOP,/* A sBx R(A)+=R(A+2);
221 if R(A) <?= R(A+1) then { pc+=sBx; R(A+3)=R(A) }*/
222OP_FORPREP,/* A sBx R(A)-=R(A+2); pc+=sBx */
223
224OP_TFORCALL,/* A C R(A+3), ... ,R(A+2+C) := R(A)(R(A+1), R(A+2)); */
225OP_TFORLOOP,/* A sBx if R(A+1) ~= nil then { R(A)=R(A+1); pc += sBx }*/
226
227OP_SETLIST,/* A B C R(A)[(C-1)*FPF+i] := R(A+i), 1 <= i <= B */
228
229OP_CLOSURE,/* A Bx R(A) := closure(KPROTO[Bx]) */
230
231OP_VARARG,/* A B R(A), R(A+1), ..., R(A+B-2) = vararg */
232
233OP_EXTRAARG/* Ax extra (larger) argument for previous opcode */
234} OpCode;
235
236
237#define NUM_OPCODES (cast(int, OP_EXTRAARG) + 1)
238
239
240
241/*===========================================================================
242 Notes:
243 (*) In OP_CALL, if (B == 0) then B = top. If (C == 0), then 'top' is
244 set to last_result+1, so next open instruction (OP_CALL, OP_RETURN,
245 OP_SETLIST) may use 'top'.
246
247 (*) In OP_VARARG, if (B == 0) then use actual number of varargs and
248 set top (like in OP_CALL with C == 0).
249
250 (*) In OP_RETURN, if (B == 0) then return up to 'top'.
251
252 (*) In OP_SETLIST, if (B == 0) then B = 'top'; if (C == 0) then next
253 'instruction' is EXTRAARG(real C).
254
255 (*) In OP_LOADKX, the next 'instruction' is always EXTRAARG.
256
257 (*) For comparisons, A specifies what condition the test should accept
258 (true or false).
259
260 (*) All 'skips' (pc++) assume that next instruction is a jump.
261
262===========================================================================*/
263
264
265/*
266** masks for instruction properties. The format is:
267** bits 0-1: op mode
268** bits 2-3: C arg mode
269** bits 4-5: B arg mode
270** bit 6: instruction set register A
271** bit 7: operator is a test (next instruction must be a jump)
272*/
273
274enum OpArgMask {
275 OpArgN, /* argument is not used */
276 OpArgU, /* argument is used */
277 OpArgR, /* argument is a register or a jump offset */
278 OpArgK /* argument is a constant or register/constant */
279};
280
281LUAI_DDEC const lu_byte luaP_opmodes[NUM_OPCODES];
282
283#define getOpMode(m) (cast(enum OpMode, luaP_opmodes[m] & 3))
284#define getBMode(m) (cast(enum OpArgMask, (luaP_opmodes[m] >> 4) & 3))
285#define getCMode(m) (cast(enum OpArgMask, (luaP_opmodes[m] >> 2) & 3))
286#define testAMode(m) (luaP_opmodes[m] & (1 << 6))
287#define testTMode(m) (luaP_opmodes[m] & (1 << 7))
288
289
290LUAI_DDEC const char *const luaP_opnames[NUM_OPCODES+1]; /* opcode names */
291
292
293/* number of list items to accumulate before a SETLIST instruction */
294#define LFIELDS_PER_FLUSH 50
295
296
297#endif
298