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Luaj 2.0 for the jse platform
/*******************************************************************************
* Copyright (c) 2009 Luaj.org. All rights reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
******************************************************************************/
package org.luaj.vm2;
/**
* Constants for lua limits and opcodes
*/
public class Lua {
/** version is supplied by ant build task */
public static final String _VERSION = "Luaj-jse 2.0";
/** use return values from previous op */
public static final int LUA_MULTRET = -1;
/** masks for new-style vararg */
public static final int VARARG_HASARG = 1;
public static final int VARARG_ISVARARG = 2;
public static final int VARARG_NEEDSARG = 4;
// from lopcodes.h
/*===========================================================================
We assume that instructions are unsigned numbers.
All instructions have an opcode in the first 6 bits.
Instructions can have the following fields:
`A' : 8 bits
`B' : 9 bits
`C' : 9 bits
`Bx' : 18 bits (`B' and `C' together)
`sBx' : signed Bx
A signed argument is represented in excess K; that is, the number
value is the unsigned value minus K. K is exactly the maximum value
for that argument (so that -max is represented by 0, and +max is
represented by 2*max), which is half the maximum for the corresponding
unsigned argument.
===========================================================================*/
/* basic instruction format */
public static final int iABC = 0;
public static final int iABx = 1;
public static final int iAsBx = 2;
/*
** size and position of opcode arguments.
*/
public static final int SIZE_C = 9;
public static final int SIZE_B = 9;
public static final int SIZE_Bx = (SIZE_C + SIZE_B);
public static final int SIZE_A = 8;
public static final int SIZE_OP = 6;
public static final int POS_OP = 0;
public static final int POS_A = (POS_OP + SIZE_OP);
public static final int POS_C = (POS_A + SIZE_A);
public static final int POS_B = (POS_C + SIZE_C);
public static final int POS_Bx = POS_C;
public static final int MAX_OP = ((1<>1); /* `sBx' is signed */
public static final int MASK_OP = ((1<> POS_OP) & MAX_OP;
}
public static int GETARG_A(int i) {
return (i >> POS_A) & MAXARG_A;
}
public static int GETARG_B(int i) {
return (i >> POS_B) & MAXARG_B;
}
public static int GETARG_C(int i) {
return (i >> POS_C) & MAXARG_C;
}
public static int GETARG_Bx(int i) {
return (i >> POS_Bx) & MAXARG_Bx;
}
public static int GETARG_sBx(int i) {
return ((i >> POS_Bx) & MAXARG_Bx) - MAXARG_sBx;
}
/*
** Macros to operate RK indices
*/
/** this bit 1 means constant (0 means register) */
public static final int BITRK = (1 << (SIZE_B - 1));
/** test whether value is a constant */
public static boolean ISK(int x) {
return 0 != ((x) & BITRK);
}
/** gets the index of the constant */
public static int INDEXK(int r) {
return ((int)(r) & ~BITRK);
}
public static final int MAXINDEXRK = (BITRK - 1);
/** code a constant index as a RK value */
public static int RKASK(int x) {
return ((x) | BITRK);
}
/**
** invalid register that fits in 8 bits
*/
public static final int NO_REG = MAXARG_A;
/*
** R(x) - register
** Kst(x) - constant (in constant table)
** RK(x) == if ISK(x) then Kst(INDEXK(x)) else R(x)
*/
/*
** grep "ORDER OP" if you change these enums
*/
/*----------------------------------------------------------------------
name args description
------------------------------------------------------------------------*/
public static final int OP_MOVE = 0;/* A B R(A) := R(B) */
public static final int OP_LOADK = 1;/* A Bx R(A) := Kst(Bx) */
public static final int OP_LOADBOOL = 2;/* A B C R(A) := (Bool)B; if (C) pc++ */
public static final int OP_LOADNIL = 3; /* A B R(A) := ... := R(B) := nil */
public static final int OP_GETUPVAL = 4; /* A B R(A) := UpValue[B] */
public static final int OP_GETGLOBAL = 5; /* A Bx R(A) := Gbl[Kst(Bx)] */
public static final int OP_GETTABLE = 6; /* A B C R(A) := R(B)[RK(C)] */
public static final int OP_SETGLOBAL = 7; /* A Bx Gbl[Kst(Bx)] := R(A) */
public static final int OP_SETUPVAL = 8; /* A B UpValue[B] := R(A) */
public static final int OP_SETTABLE = 9; /* A B C R(A)[RK(B)] := RK(C) */
public static final int OP_NEWTABLE = 10; /* A B C R(A) := {} (size = B,C) */
public static final int OP_SELF = 11; /* A B C R(A+1) := R(B); R(A) := R(B)[RK(C)] */
public static final int OP_ADD = 12; /* A B C R(A) := RK(B) + RK(C) */
public static final int OP_SUB = 13; /* A B C R(A) := RK(B) - RK(C) */
public static final int OP_MUL = 14; /* A B C R(A) := RK(B) * RK(C) */
public static final int OP_DIV = 15; /* A B C R(A) := RK(B) / RK(C) */
public static final int OP_MOD = 16; /* A B C R(A) := RK(B) % RK(C) */
public static final int OP_POW = 17; /* A B C R(A) := RK(B) ^ RK(C) */
public static final int OP_UNM = 18; /* A B R(A) := -R(B) */
public static final int OP_NOT = 19; /* A B R(A) := not R(B) */
public static final int OP_LEN = 20; /* A B R(A) := length of R(B) */
public static final int OP_CONCAT = 21; /* A B C R(A) := R(B).. ... ..R(C) */
public static final int OP_JMP = 22; /* sBx pc+=sBx */
public static final int OP_EQ = 23; /* A B C if ((RK(B) == RK(C)) ~= A) then pc++ */
public static final int OP_LT = 24; /* A B C if ((RK(B) < RK(C)) ~= A) then pc++ */
public static final int OP_LE = 25; /* A B C if ((RK(B) <= RK(C)) ~= A) then pc++ */
public static final int OP_TEST = 26; /* A C if not (R(A) <=> C) then pc++ */
public static final int OP_TESTSET = 27; /* A B C if (R(B) <=> C) then R(A) := R(B) else pc++ */
public static final int OP_CALL = 28; /* A B C R(A), ... ,R(A+C-2) := R(A)(R(A+1), ... ,R(A+B-1)) */
public static final int OP_TAILCALL = 29; /* A B C return R(A)(R(A+1), ... ,R(A+B-1)) */
public static final int OP_RETURN = 30; /* A B return R(A), ... ,R(A+B-2) (see note) */
public static final int OP_FORLOOP = 31; /* A sBx R(A)+=R(A+2);
if R(A) =) R(A)*/
public static final int OP_CLOSURE = 36; /* A Bx R(A) := closure(KPROTO[Bx], R(A), ... ,R(A+n)) */
public static final int OP_VARARG = 37; /* A B R(A), R(A+1), ..., R(A+B-1) = vararg */
public static final int NUM_OPCODES = OP_VARARG + 1;
/* pseudo-opcodes used in parsing only. */
public static final int OP_GT = 63; // >
public static final int OP_GE = 62; // >=
public static final int OP_NEQ = 61; // ~=
public static final int OP_AND = 60; // and
public static final int OP_OR = 59; // or
/*===========================================================================
Notes:
(*) In OP_CALL, if (B == 0) then B = top. C is the number of returns - 1,
and can be 0: OP_CALL then sets `top' to last_result+1, so
next open instruction (OP_CALL, OP_RETURN, OP_SETLIST) may use `top'.
(*) In OP_VARARG, if (B == 0) then use actual number of varargs and
set top (like in OP_CALL with C == 0).
(*) In OP_RETURN, if (B == 0) then return up to `top'
(*) In OP_SETLIST, if (B == 0) then B = `top';
if (C == 0) then next `instruction' is real C
(*) For comparisons, A specifies what condition the test should accept
(true or false).
(*) All `skips' (pc++) assume that next instruction is a jump
===========================================================================*/
/*
** masks for instruction properties. The format is:
** bits 0-1: op mode
** bits 2-3: C arg mode
** bits 4-5: B arg mode
** bit 6: instruction set register A
** bit 7: operator is a test
*/
public static final int OpArgN = 0; /* argument is not used */
public static final int OpArgU = 1; /* argument is used */
public static final int OpArgR = 2; /* argument is a register or a jump offset */
public static final int OpArgK = 3; /* argument is a constant or register/constant */
public static final int[] luaP_opmodes = {
/* T A B C mode opcode */
(0<<7) | (1<<6) | (OpArgR<<4) | (OpArgN<<2) | (iABC), /* OP_MOVE */
(0<<7) | (1<<6) | (OpArgK<<4) | (OpArgN<<2) | (iABx), /* OP_LOADK */
(0<<7) | (1<<6) | (OpArgU<<4) | (OpArgU<<2) | (iABC), /* OP_LOADBOOL */
(0<<7) | (1<<6) | (OpArgR<<4) | (OpArgN<<2) | (iABC), /* OP_LOADNIL */
(0<<7) | (1<<6) | (OpArgU<<4) | (OpArgN<<2) | (iABC), /* OP_GETUPVAL */
(0<<7) | (1<<6) | (OpArgK<<4) | (OpArgN<<2) | (iABx), /* OP_GETGLOBAL */
(0<<7) | (1<<6) | (OpArgR<<4) | (OpArgK<<2) | (iABC), /* OP_GETTABLE */
(0<<7) | (0<<6) | (OpArgK<<4) | (OpArgN<<2) | (iABx), /* OP_SETGLOBAL */
(0<<7) | (0<<6) | (OpArgU<<4) | (OpArgN<<2) | (iABC), /* OP_SETUPVAL */
(0<<7) | (0<<6) | (OpArgK<<4) | (OpArgK<<2) | (iABC), /* OP_SETTABLE */
(0<<7) | (1<<6) | (OpArgU<<4) | (OpArgU<<2) | (iABC), /* OP_NEWTABLE */
(0<<7) | (1<<6) | (OpArgR<<4) | (OpArgK<<2) | (iABC), /* OP_SELF */
(0<<7) | (1<<6) | (OpArgK<<4) | (OpArgK<<2) | (iABC), /* OP_ADD */
(0<<7) | (1<<6) | (OpArgK<<4) | (OpArgK<<2) | (iABC), /* OP_SUB */
(0<<7) | (1<<6) | (OpArgK<<4) | (OpArgK<<2) | (iABC), /* OP_MUL */
(0<<7) | (1<<6) | (OpArgK<<4) | (OpArgK<<2) | (iABC), /* OP_DIV */
(0<<7) | (1<<6) | (OpArgK<<4) | (OpArgK<<2) | (iABC), /* OP_MOD */
(0<<7) | (1<<6) | (OpArgK<<4) | (OpArgK<<2) | (iABC), /* OP_POW */
(0<<7) | (1<<6) | (OpArgR<<4) | (OpArgN<<2) | (iABC), /* OP_UNM */
(0<<7) | (1<<6) | (OpArgR<<4) | (OpArgN<<2) | (iABC), /* OP_NOT */
(0<<7) | (1<<6) | (OpArgR<<4) | (OpArgN<<2) | (iABC), /* OP_LEN */
(0<<7) | (1<<6) | (OpArgR<<4) | (OpArgR<<2) | (iABC), /* OP_CONCAT */
(0<<7) | (0<<6) | (OpArgR<<4) | (OpArgN<<2) | (iAsBx), /* OP_JMP */
(1<<7) | (0<<6) | (OpArgK<<4) | (OpArgK<<2) | (iABC), /* OP_EQ */
(1<<7) | (0<<6) | (OpArgK<<4) | (OpArgK<<2) | (iABC), /* OP_LT */
(1<<7) | (0<<6) | (OpArgK<<4) | (OpArgK<<2) | (iABC), /* OP_LE */
(1<<7) | (1<<6) | (OpArgR<<4) | (OpArgU<<2) | (iABC), /* OP_TEST */
(1<<7) | (1<<6) | (OpArgR<<4) | (OpArgU<<2) | (iABC), /* OP_TESTSET */
(0<<7) | (1<<6) | (OpArgU<<4) | (OpArgU<<2) | (iABC), /* OP_CALL */
(0<<7) | (1<<6) | (OpArgU<<4) | (OpArgU<<2) | (iABC), /* OP_TAILCALL */
(0<<7) | (0<<6) | (OpArgU<<4) | (OpArgN<<2) | (iABC), /* OP_RETURN */
(0<<7) | (1<<6) | (OpArgR<<4) | (OpArgN<<2) | (iAsBx), /* OP_FORLOOP */
(0<<7) | (1<<6) | (OpArgR<<4) | (OpArgN<<2) | (iAsBx), /* OP_FORPREP */
(1<<7) | (0<<6) | (OpArgN<<4) | (OpArgU<<2) | (iABC), /* OP_TFORLOOP */
(0<<7) | (0<<6) | (OpArgU<<4) | (OpArgU<<2) | (iABC), /* OP_SETLIST */
(0<<7) | (0<<6) | (OpArgN<<4) | (OpArgN<<2) | (iABC), /* OP_CLOSE */
(0<<7) | (1<<6) | (OpArgU<<4) | (OpArgN<<2) | (iABx), /* OP_CLOSURE */
(0<<7) | (1<<6) | (OpArgU<<4) | (OpArgN<<2) | (iABC), /* OP_VARARG */
};
public static int getOpMode(int m) {
return luaP_opmodes[m] & 3;
}
public static int getBMode(int m) {
return (luaP_opmodes[m] >> 4) & 3;
}
public static int getCMode(int m) {
return (luaP_opmodes[m] >> 2) & 3;
}
public static boolean testAMode(int m) {
return 0 != (luaP_opmodes[m] & (1 << 6));
}
public static boolean testTMode(int m) {
return 0 != (luaP_opmodes[m] & (1 << 7));
}
/* number of list items to accumulate before a SETLIST instruction */
public static final int LFIELDS_PER_FLUSH = 50;
}