1 /* $NetBSD: lopcodes.h,v 1.8 2018/08/04 17:30:01 alnsn Exp $ */ 2 3 /* 4 ** Id: lopcodes.h,v 1.149.1.1 2017/04/19 17:20:42 roberto Exp 5 ** Opcodes for Lua virtual machine 6 ** See Copyright Notice in lua.h 7 */ 8 9 #ifndef lopcodes_h 10 #define lopcodes_h 11 12 #include "llimits.h" 13 14 15 /*=========================================================================== 16 We assume that instructions are unsigned numbers. 17 All instructions have an opcode in the first 6 bits. 18 Instructions can have the following fields: 19 'A' : 8 bits 20 'B' : 9 bits 21 'C' : 9 bits 22 'Ax' : 26 bits ('A', 'B', and 'C' together) 23 'Bx' : 18 bits ('B' and 'C' together) 24 'sBx' : signed Bx 25 26 A signed argument is represented in excess K; that is, the number 27 value is the unsigned value minus K. K is exactly the maximum value 28 for that argument (so that -max is represented by 0, and +max is 29 represented by 2*max), which is half the maximum for the corresponding 30 unsigned argument. 31 ===========================================================================*/ 32 33 34 enum OpMode {iABC, iABx, iAsBx, iAx}; /* basic instruction format */ 35 36 37 /* 38 ** size and position of opcode arguments. 39 */ 40 #define SIZE_C 9 41 #define SIZE_B 9 42 #define SIZE_Bx (SIZE_C + SIZE_B) 43 #define SIZE_A 8 44 #define SIZE_Ax (SIZE_C + SIZE_B + SIZE_A) 45 46 #define SIZE_OP 6 47 48 #define POS_OP 0 49 #define POS_A (POS_OP + SIZE_OP) 50 #define POS_C (POS_A + SIZE_A) 51 #define POS_B (POS_C + SIZE_C) 52 #define POS_Bx POS_C 53 #define POS_Ax POS_A 54 55 56 /* 57 ** limits for opcode arguments. 58 ** we use (signed) int to manipulate most arguments, 59 ** so they must fit in LUAI_BITSINT-1 bits (-1 for sign) 60 */ 61 #if SIZE_Bx < LUAI_BITSINT-1 62 #define MAXARG_Bx ((1<<SIZE_Bx)-1) 63 #define MAXARG_sBx (MAXARG_Bx>>1) /* 'sBx' is signed */ 64 #else 65 #define MAXARG_Bx MAX_INT 66 #define MAXARG_sBx MAX_INT 67 #endif 68 69 #if SIZE_Ax < LUAI_BITSINT-1 70 #define MAXARG_Ax ((1<<SIZE_Ax)-1) 71 #else 72 #define MAXARG_Ax MAX_INT 73 #endif 74 75 76 #define MAXARG_A ((1<<SIZE_A)-1) 77 #define MAXARG_B ((1<<SIZE_B)-1) 78 #define MAXARG_C ((1<<SIZE_C)-1) 79 80 81 /* creates a mask with 'n' 1 bits at position 'p' */ 82 #define MASK1(n,p) ((~((~(Instruction)0)<<(n)))<<(p)) 83 84 /* creates a mask with 'n' 0 bits at position 'p' */ 85 #define MASK0(n,p) (~MASK1(n,p)) 86 87 /* 88 ** the following macros help to manipulate instructions 89 */ 90 91 #define GET_OPCODE(i) (cast(OpCode, ((i)>>POS_OP) & MASK1(SIZE_OP,0))) 92 #define SET_OPCODE(i,o) ((i) = (((i)&MASK0(SIZE_OP,POS_OP)) | \ 93 ((cast(Instruction, o)<<POS_OP)&MASK1(SIZE_OP,POS_OP)))) 94 95 #define getarg(i,pos,size) (cast(int, ((i)>>pos) & MASK1(size,0))) 96 #define setarg(i,v,pos,size) ((i) = (((i)&MASK0(size,pos)) | \ 97 ((cast(Instruction, v)<<pos)&MASK1(size,pos)))) 98 99 #define GETARG_A(i) getarg(i, POS_A, SIZE_A) 100 #define SETARG_A(i,v) setarg(i, v, POS_A, SIZE_A) 101 102 #define GETARG_B(i) getarg(i, POS_B, SIZE_B) 103 #define SETARG_B(i,v) setarg(i, v, POS_B, SIZE_B) 104 105 #define GETARG_C(i) getarg(i, POS_C, SIZE_C) 106 #define SETARG_C(i,v) setarg(i, v, POS_C, SIZE_C) 107 108 #define GETARG_Bx(i) getarg(i, POS_Bx, SIZE_Bx) 109 #define SETARG_Bx(i,v) setarg(i, v, POS_Bx, SIZE_Bx) 110 111 #define GETARG_Ax(i) getarg(i, POS_Ax, SIZE_Ax) 112 #define SETARG_Ax(i,v) setarg(i, v, POS_Ax, SIZE_Ax) 113 114 #define GETARG_sBx(i) (GETARG_Bx(i)-MAXARG_sBx) 115 #define SETARG_sBx(i,b) SETARG_Bx((i),cast(unsigned int, (b)+MAXARG_sBx)) 116 117 118 #define CREATE_ABC(o,a,b,c) ((cast(Instruction, o)<<POS_OP) \ 119 | (cast(Instruction, a)<<POS_A) \ 120 | (cast(Instruction, b)<<POS_B) \ 121 | (cast(Instruction, c)<<POS_C)) 122 123 #define CREATE_ABx(o,a,bc) ((cast(Instruction, o)<<POS_OP) \ 124 | (cast(Instruction, a)<<POS_A) \ 125 | (cast(Instruction, bc)<<POS_Bx)) 126 127 #define CREATE_Ax(o,a) ((cast(Instruction, o)<<POS_OP) \ 128 | (cast(Instruction, a)<<POS_Ax)) 129 130 131 /* 132 ** Macros to operate RK indices 133 */ 134 135 /* this bit 1 means constant (0 means register) */ 136 #define BITRK (1 << (SIZE_B - 1)) 137 138 /* test whether value is a constant */ 139 #define ISK(x) ((x) & BITRK) 140 141 /* gets the index of the constant */ 142 #define INDEXK(r) ((int)(r) & ~BITRK) 143 144 #if !defined(MAXINDEXRK) /* (for debugging only) */ 145 #define MAXINDEXRK (BITRK - 1) 146 #endif 147 148 /* code a constant index as a RK value */ 149 #define RKASK(x) ((x) | BITRK) 150 151 152 /* 153 ** invalid register that fits in 8 bits 154 */ 155 #define NO_REG MAXARG_A 156 157 158 /* 159 ** R(x) - register 160 ** Kst(x) - constant (in constant table) 161 ** RK(x) == if ISK(x) then Kst(INDEXK(x)) else R(x) 162 */ 163 164 165 /* 166 ** grep "ORDER OP" if you change these enums 167 */ 168 169 typedef enum { 170 /*---------------------------------------------------------------------- 171 name args description 172 ------------------------------------------------------------------------*/ 173 OP_MOVE,/* A B R(A) := R(B) */ 174 OP_LOADK,/* A Bx R(A) := Kst(Bx) */ 175 OP_LOADKX,/* A R(A) := Kst(extra arg) */ 176 OP_LOADBOOL,/* A B C R(A) := (Bool)B; if (C) pc++ */ 177 OP_LOADNIL,/* A B R(A), R(A+1), ..., R(A+B) := nil */ 178 OP_GETUPVAL,/* A B R(A) := UpValue[B] */ 179 180 OP_GETTABUP,/* A B C R(A) := UpValue[B][RK(C)] */ 181 OP_GETTABLE,/* A B C R(A) := R(B)[RK(C)] */ 182 183 OP_SETTABUP,/* A B C UpValue[A][RK(B)] := RK(C) */ 184 OP_SETUPVAL,/* A B UpValue[B] := R(A) */ 185 OP_SETTABLE,/* A B C R(A)[RK(B)] := RK(C) */ 186 187 OP_NEWTABLE,/* A B C R(A) := {} (size = B,C) */ 188 189 OP_SELF,/* A B C R(A+1) := R(B); R(A) := R(B)[RK(C)] */ 190 191 OP_ADD,/* A B C R(A) := RK(B) + RK(C) */ 192 OP_SUB,/* A B C R(A) := RK(B) - RK(C) */ 193 OP_MUL,/* A B C R(A) := RK(B) * RK(C) */ 194 OP_MOD,/* A B C R(A) := RK(B) % RK(C) */ 195 #ifndef _KERNEL 196 OP_POW,/* A B C R(A) := RK(B) ^ RK(C) */ 197 OP_DIV,/* A B C R(A) := RK(B) / RK(C) */ 198 #endif /* _KERNEL */ 199 OP_IDIV,/* A B C R(A) := RK(B) // RK(C) */ 200 OP_BAND,/* A B C R(A) := RK(B) & RK(C) */ 201 OP_BOR,/* A B C R(A) := RK(B) | RK(C) */ 202 OP_BXOR,/* A B C R(A) := RK(B) ~ RK(C) */ 203 OP_SHL,/* A B C R(A) := RK(B) << RK(C) */ 204 OP_SHR,/* A B C R(A) := RK(B) >> RK(C) */ 205 OP_UNM,/* A B R(A) := -R(B) */ 206 OP_BNOT,/* A B R(A) := ~R(B) */ 207 OP_NOT,/* A B R(A) := not R(B) */ 208 OP_LEN,/* A B R(A) := length of R(B) */ 209 210 OP_CONCAT,/* A B C R(A) := R(B).. ... ..R(C) */ 211 212 OP_JMP,/* A sBx pc+=sBx; if (A) close all upvalues >= R(A - 1) */ 213 OP_EQ,/* A B C if ((RK(B) == RK(C)) ~= A) then pc++ */ 214 OP_LT,/* A B C if ((RK(B) < RK(C)) ~= A) then pc++ */ 215 OP_LE,/* A B C if ((RK(B) <= RK(C)) ~= A) then pc++ */ 216 217 OP_TEST,/* A C if not (R(A) <=> C) then pc++ */ 218 OP_TESTSET,/* A B C if (R(B) <=> C) then R(A) := R(B) else pc++ */ 219 220 OP_CALL,/* A B C R(A), ... ,R(A+C-2) := R(A)(R(A+1), ... ,R(A+B-1)) */ 221 OP_TAILCALL,/* A B C return R(A)(R(A+1), ... ,R(A+B-1)) */ 222 OP_RETURN,/* A B return R(A), ... ,R(A+B-2) (see note) */ 223 224 OP_FORLOOP,/* A sBx R(A)+=R(A+2); 225 if R(A) <?= R(A+1) then { pc+=sBx; R(A+3)=R(A) }*/ 226 OP_FORPREP,/* A sBx R(A)-=R(A+2); pc+=sBx */ 227 228 OP_TFORCALL,/* A C R(A+3), ... ,R(A+2+C) := R(A)(R(A+1), R(A+2)); */ 229 OP_TFORLOOP,/* A sBx if R(A+1) ~= nil then { R(A)=R(A+1); pc += sBx }*/ 230 231 OP_SETLIST,/* A B C R(A)[(C-1)*FPF+i] := R(A+i), 1 <= i <= B */ 232 233 OP_CLOSURE,/* A Bx R(A) := closure(KPROTO[Bx]) */ 234 235 OP_VARARG,/* A B R(A), R(A+1), ..., R(A+B-2) = vararg */ 236 237 OP_EXTRAARG/* Ax extra (larger) argument for previous opcode */ 238 } OpCode; 239 240 241 #define NUM_OPCODES (cast(int, OP_EXTRAARG) + 1) 242 243 244 245 /*=========================================================================== 246 Notes: 247 (*) In OP_CALL, if (B == 0) then B = top. If (C == 0), then 'top' is 248 set to last_result+1, so next open instruction (OP_CALL, OP_RETURN, 249 OP_SETLIST) may use 'top'. 250 251 (*) In OP_VARARG, if (B == 0) then use actual number of varargs and 252 set top (like in OP_CALL with C == 0). 253 254 (*) In OP_RETURN, if (B == 0) then return up to 'top'. 255 256 (*) In OP_SETLIST, if (B == 0) then B = 'top'; if (C == 0) then next 257 'instruction' is EXTRAARG(real C). 258 259 (*) In OP_LOADKX, the next 'instruction' is always EXTRAARG. 260 261 (*) For comparisons, A specifies what condition the test should accept 262 (true or false). 263 264 (*) All 'skips' (pc++) assume that next instruction is a jump. 265 266 ===========================================================================*/ 267 268 269 /* 270 ** masks for instruction properties. The format is: 271 ** bits 0-1: op mode 272 ** bits 2-3: C arg mode 273 ** bits 4-5: B arg mode 274 ** bit 6: instruction set register A 275 ** bit 7: operator is a test (next instruction must be a jump) 276 */ 277 278 enum OpArgMask { 279 OpArgN, /* argument is not used */ 280 OpArgU, /* argument is used */ 281 OpArgR, /* argument is a register or a jump offset */ 282 OpArgK /* argument is a constant or register/constant */ 283 }; 284 285 LUAI_DDEC const lu_byte luaP_opmodes[NUM_OPCODES]; 286 287 #define getOpMode(m) (cast(enum OpMode, luaP_opmodes[m] & 3)) 288 #define getBMode(m) (cast(enum OpArgMask, (luaP_opmodes[m] >> 4) & 3)) 289 #define getCMode(m) (cast(enum OpArgMask, (luaP_opmodes[m] >> 2) & 3)) 290 #define testAMode(m) (luaP_opmodes[m] & (1 << 6)) 291 #define testTMode(m) (luaP_opmodes[m] & (1 << 7)) 292 293 294 LUAI_DDEC const char *const luaP_opnames[NUM_OPCODES+1]; /* opcode names */ 295 296 297 /* number of list items to accumulate before a SETLIST instruction */ 298 #define LFIELDS_PER_FLUSH 50 299 300 301 #endif 302