1/* 2** $Id: lopcodes.h,v 1.142 2011/07/15 12:50:29 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#define MAXINDEXRK (BITRK - 1) 143 144/* code a constant index as a RK value */ 145#define RKASK(x) ((x) | BITRK) 146 147 148/* 149** invalid register that fits in 8 bits 150*/ 151#define NO_REG MAXARG_A 152 153 154/* 155** R(x) - register 156** Kst(x) - constant (in constant table) 157** RK(x) == if ISK(x) then Kst(INDEXK(x)) else R(x) 158*/ 159 160 161/* 162** grep "ORDER OP" if you change these enums 163*/ 164 165typedef enum { 166/*---------------------------------------------------------------------- 167name args description 168------------------------------------------------------------------------*/ 169OP_MOVE,/* A B R(A) := R(B) */ 170OP_LOADK,/* A Bx R(A) := Kst(Bx) */ 171OP_LOADKX,/* A R(A) := Kst(extra arg) */ 172OP_LOADBOOL,/* A B C R(A) := (Bool)B; if (C) pc++ */ 173OP_LOADNIL,/* A B R(A), R(A+1), ..., R(A+B) := nil */ 174OP_GETUPVAL,/* A B R(A) := UpValue[B] */ 175 176OP_GETTABUP,/* A B C R(A) := UpValue[B][RK(C)] */ 177OP_GETTABLE,/* A B C R(A) := R(B)[RK(C)] */ 178 179OP_SETTABUP,/* A B C UpValue[A][RK(B)] := RK(C) */ 180OP_SETUPVAL,/* A B UpValue[B] := R(A) */ 181OP_SETTABLE,/* A B C R(A)[RK(B)] := RK(C) */ 182 183OP_NEWTABLE,/* A B C R(A) := {} (size = B,C) */ 184 185OP_SELF,/* A B C R(A+1) := R(B); R(A) := R(B)[RK(C)] */ 186 187OP_ADD,/* A B C R(A) := RK(B) + RK(C) */ 188OP_SUB,/* A B C R(A) := RK(B) - RK(C) */ 189OP_MUL,/* A B C R(A) := RK(B) * RK(C) */ 190OP_DIV,/* A B C R(A) := RK(B) / RK(C) */ 191OP_MOD,/* A B C R(A) := RK(B) % RK(C) */ 192OP_POW,/* A B C R(A) := RK(B) ^ RK(C) */ 193OP_UNM,/* A B R(A) := -R(B) */ 194OP_NOT,/* A B R(A) := not R(B) */ 195OP_LEN,/* A B R(A) := length of R(B) */ 196 197OP_CONCAT,/* A B C R(A) := R(B).. ... ..R(C) */ 198 199OP_JMP,/* A sBx pc+=sBx; if (A) close all upvalues >= R(A) + 1 */ 200OP_EQ,/* A B C if ((RK(B) == RK(C)) ~= A) then pc++ */ 201OP_LT,/* A B C if ((RK(B) < RK(C)) ~= A) then pc++ */ 202OP_LE,/* A B C if ((RK(B) <= RK(C)) ~= A) then pc++ */ 203 204OP_TEST,/* A C if not (R(A) <=> C) then pc++ */ 205OP_TESTSET,/* A B C if (R(B) <=> C) then R(A) := R(B) else pc++ */ 206 207OP_CALL,/* A B C R(A), ... ,R(A+C-2) := R(A)(R(A+1), ... ,R(A+B-1)) */ 208OP_TAILCALL,/* A B C return R(A)(R(A+1), ... ,R(A+B-1)) */ 209OP_RETURN,/* A B return R(A), ... ,R(A+B-2) (see note) */ 210 211OP_FORLOOP,/* A sBx R(A)+=R(A+2); 212 if R(A) <?= R(A+1) then { pc+=sBx; R(A+3)=R(A) }*/ 213OP_FORPREP,/* A sBx R(A)-=R(A+2); pc+=sBx */ 214 215OP_TFORCALL,/* A C R(A+3), ... ,R(A+2+C) := R(A)(R(A+1), R(A+2)); */ 216OP_TFORLOOP,/* A sBx if R(A+1) ~= nil then { R(A)=R(A+1); pc += sBx }*/ 217 218OP_SETLIST,/* A B C R(A)[(C-1)*FPF+i] := R(A+i), 1 <= i <= B */ 219 220OP_CLOSURE,/* A Bx R(A) := closure(KPROTO[Bx]) */ 221 222OP_VARARG,/* A B R(A), R(A+1), ..., R(A+B-2) = vararg */ 223 224OP_EXTRAARG/* Ax extra (larger) argument for previous opcode */ 225} OpCode; 226 227 228#define NUM_OPCODES (cast(int, OP_EXTRAARG) + 1) 229 230 231 232/*=========================================================================== 233 Notes: 234 (*) In OP_CALL, if (B == 0) then B = top. If (C == 0), then `top' is 235 set to last_result+1, so next open instruction (OP_CALL, OP_RETURN, 236 OP_SETLIST) may use `top'. 237 238 (*) In OP_VARARG, if (B == 0) then use actual number of varargs and 239 set top (like in OP_CALL with C == 0). 240 241 (*) In OP_RETURN, if (B == 0) then return up to `top'. 242 243 (*) In OP_SETLIST, if (B == 0) then B = `top'; if (C == 0) then next 244 'instruction' is EXTRAARG(real C). 245 246 (*) In OP_LOADKX, the next 'instruction' is always EXTRAARG. 247 248 (*) For comparisons, A specifies what condition the test should accept 249 (true or false). 250 251 (*) All `skips' (pc++) assume that next instruction is a jump. 252 253===========================================================================*/ 254 255 256/* 257** masks for instruction properties. The format is: 258** bits 0-1: op mode 259** bits 2-3: C arg mode 260** bits 4-5: B arg mode 261** bit 6: instruction set register A 262** bit 7: operator is a test (next instruction must be a jump) 263*/ 264 265enum OpArgMask { 266 OpArgN, /* argument is not used */ 267 OpArgU, /* argument is used */ 268 OpArgR, /* argument is a register or a jump offset */ 269 OpArgK /* argument is a constant or register/constant */ 270}; 271 272LUAI_DDEC const lu_byte luaP_opmodes[NUM_OPCODES]; 273 274#define getOpMode(m) (cast(enum OpMode, luaP_opmodes[m] & 3)) 275#define getBMode(m) (cast(enum OpArgMask, (luaP_opmodes[m] >> 4) & 3)) 276#define getCMode(m) (cast(enum OpArgMask, (luaP_opmodes[m] >> 2) & 3)) 277#define testAMode(m) (luaP_opmodes[m] & (1 << 6)) 278#define testTMode(m) (luaP_opmodes[m] & (1 << 7)) 279 280 281LUAI_DDEC const char *const luaP_opnames[NUM_OPCODES+1]; /* opcode names */ 282 283 284/* number of list items to accumulate before a SETLIST instruction */ 285#define LFIELDS_PER_FLUSH 50 286 287 288#endif 289