Merge pull request #2 from giann/feature/lex-parse

Lexing & Parsing

1 files changed, 208 insertions, 24 deletions

diff --git a/src/lopcodes.js b/src/lopcodes.js
index 5723abb..bfcd993 100644
--- a/src/lopcodes.js
+++ b/src/lopcodes.js
@@ -51,6 +51,56 @@ const OpCodes = [
     "OP_EXTRAARG"
 ];
 
+const OpCodesI = {
+    OP_MOVE:     0,
+    OP_LOADK:    1,
+    OP_LOADKX:   2,
+    OP_LOADBOOL: 3,
+    OP_LOADNIL:  4,
+    OP_GETUPVAL: 5,
+    OP_GETTABUP: 6,
+    OP_GETTABLE: 7,
+    OP_SETTABUP: 8,
+    OP_SETUPVAL: 9,
+    OP_SETTABLE: 10,
+    OP_NEWTABLE: 11,
+    OP_SELF:     12,
+    OP_ADD:      13,
+    OP_SUB:      14,
+    OP_MUL:      15,
+    OP_MOD:      16,
+    OP_POW:      17,
+    OP_DIV:      18,
+    OP_IDIV:     19,
+    OP_BAND:     20,
+    OP_BOR:      21,
+    OP_BXOR:     22,
+    OP_SHL:      23,
+    OP_SHR:      24,
+    OP_UNM:      25,
+    OP_BNOT:     26,
+    OP_NOT:      27,
+    OP_LEN:      28,
+    OP_CONCAT:   29,
+    OP_JMP:      30,
+    OP_EQ:       31,
+    OP_LT:       32,
+    OP_LE:       33,
+    OP_TEST:     34,
+    OP_TESTSET:  35,
+    OP_CALL:     36,
+    OP_TAILCALL: 37,
+    OP_RETURN:   38,
+    OP_FORLOOP:  39,
+    OP_FORPREP:  40,
+    OP_TFORCALL: 41,
+    OP_TFORLOOP: 42,
+    OP_SETLIST:  43,
+    OP_CLOSURE:  44,
+    OP_VARARG:   45,
+    OP_EXTRAARG: 46
+};
+
 /*
 ** masks for instruction properties. The format is:
 ** bits 0-1: op mode
@@ -120,10 +170,26 @@ const luaP_opmodes = [
     0 << 7 | 0 << 6 | OpArgU << 4 | OpArgU << 2 | iAx     /* OP_EXTRAARG */
 ];
 
+const getOpMode = function(m) {
+    return luaP_opmodes[m] & 3;
+};
+
+const getBMode = function(m) {
+    return (luaP_opmodes[m] >> 4) & 3;
+};
+
+const getCMode = function(m) {
+    return (luaP_opmodes[m] >> 2) & 3;
+};
+
 const testAMode = function(m) {
     return luaP_opmodes[m] & (1 << 6);
 };
 
+const testTMode = function(m) {
+    return luaP_opmodes[m] & (1 << 7);
+};
+
 const SIZE_C     = 9;
 const SIZE_B     = 9;
 const SIZE_Bx    = (SIZE_C + SIZE_B);
@@ -143,40 +209,158 @@ const MAXARG_A   = ((1 << SIZE_A) - 1);
 const MAXARG_B   = ((1 << SIZE_B) - 1);
 const MAXARG_C   = ((1 << SIZE_C) - 1);
 
+/* this bit 1 means constant (0 means register) */
 const BITRK      = (1 << (SIZE_B - 1));
 
+/*
+** invalid register that fits in 8 bits
+*/
+const NO_REG     = MAXARG_A;
+
+/* test whether value is a constant */
 const ISK = function (x) {
     return x & BITRK;
 };
 
+/* gets the index of the constant */
 const INDEXK = function (r) {
     return r & ~BITRK;
 };
 
+/* code a constant index as a RK value */
+const RKASK = function(x) {
+    return x | BITRK;
+};
+
+
+/* creates a mask with 'n' 1 bits at position 'p' */
+const MASK1 = function(n, p) {
+    return ((~((~0)<<(n)))<<(p));
+};
+
+/* creates a mask with 'n' 0 bits at position 'p' */
+const MASK0 = function(n, p) {
+    return (~MASK1(n, p));
+};
+
+const setarg = function(i, v, pos, size) {
+    i.code = (i.code & MASK0(size, pos)) | ((v << pos) & MASK1(size, pos));
+    fullins(i);
+};
+
+const SETARG_A = function(i,v) {
+    setarg(i, v, POS_A, SIZE_A);
+};
+
+const SETARG_B = function(i,v) {
+    setarg(i, v, POS_B, SIZE_B);
+};
+
+const SETARG_C = function(i,v) {
+    setarg(i, v, POS_C, SIZE_C);
+};
+
+const SETARG_Bx = function(i,v) {
+    setarg(i, v, POS_Bx, SIZE_Bx);
+};
+
+const SETARG_Ax = function(i,v) {
+    setarg(i, v, POS_Ax, SIZE_Ax);
+};
+
+const SETARG_sBx = function(i, b) {
+    SETARG_Bx(i, b + MAXARG_sBx);
+};
+
+/*
+** Pre-calculate all possible part of the instruction
+*/
+const fullins = function(ins) {
+    if (typeof ins === "number") {
+        return {
+            code:   ins,
+            opcode: (ins >> POS_OP) & MASK1(SIZE_OP, 0),
+            A:      (ins >> POS_A)  & MASK1(SIZE_A,  0),
+            B:      (ins >> POS_B)  & MASK1(SIZE_B,  0),
+            C:      (ins >> POS_C)  & MASK1(SIZE_C,  0),
+            Bx:     (ins >> POS_Bx) & MASK1(SIZE_Bx, 0),
+            Ax:     (ins >> POS_Ax) & MASK1(SIZE_Ax, 0),
+            sBx:    ((ins >> POS_Bx) & MASK1(SIZE_Bx, 0)) - MAXARG_sBx
+        };
+    } else {
+        let i = ins.code;
+        ins.opcode = (i >> POS_OP) & MASK1(SIZE_OP, 0);
+        ins.A      = (i >> POS_A)  & MASK1(SIZE_A,  0);
+        ins.B      = (i >> POS_B)  & MASK1(SIZE_B,  0);
+        ins.C      = (i >> POS_C)  & MASK1(SIZE_C,  0);
+        ins.Bx     = (i >> POS_Bx) & MASK1(SIZE_Bx, 0);
+        ins.Ax     = (i >> POS_Ax) & MASK1(SIZE_Ax, 0);
+        ins.sBx    = ((i >> POS_Bx) & MASK1(SIZE_Bx, 0)) - MAXARG_sBx;
+        return ins;
+    }
+};
+
+const CREATE_ABC = function(o, a, b, c) {
+    return fullins(o << POS_OP | a << POS_A | b << POS_B | c << POS_C);
+};
+
+const CREATE_ABx = function(o, a, bc) {
+    return fullins(o << POS_OP | a << POS_A | bc << POS_Bx);
+};
+
+const CREATE_Ax = function(o, a) {
+    return fullins(o << POS_OP | a << POS_Ax);
+};
+
 /* number of list items to accumulate before a SETLIST instruction */
 const LFIELDS_PER_FLUSH = 50;
 
-module.exports.OpCodes           = OpCodes;
-module.exports.SIZE_C            = SIZE_C;
-module.exports.SIZE_B            = SIZE_B;
-module.exports.SIZE_Bx           = SIZE_Bx;
-module.exports.SIZE_A            = SIZE_A;
-module.exports.SIZE_Ax           = SIZE_Ax;
-module.exports.SIZE_OP           = SIZE_OP;
-module.exports.POS_OP            = POS_OP;
-module.exports.POS_A             = POS_A;
-module.exports.POS_C             = POS_C;
-module.exports.POS_B             = POS_B;
-module.exports.POS_Bx            = POS_Bx;
-module.exports.POS_Ax            = POS_Ax;
-module.exports.MAXARG_Bx         = MAXARG_Bx;
-module.exports.MAXARG_sBx        = MAXARG_sBx;
-module.exports.MAXARG_Ax         = MAXARG_Ax;
-module.exports.MAXARG_A          = MAXARG_A;
-module.exports.MAXARG_B          = MAXARG_B;
-module.exports.MAXARG_C          = MAXARG_C;
-module.exports.BITRK             = BITRK;
-module.exports.ISK               = ISK;
-module.exports.INDEXK            = INDEXK;
-module.exports.LFIELDS_PER_FLUSH = LFIELDS_PER_FLUSH;
-module.exports.testAMode         = testAMode;
\ No newline at end of file
+module.exports.BITRK               = BITRK;
+module.exports.CREATE_ABC          = CREATE_ABC;
+module.exports.CREATE_ABx          = CREATE_ABx;
+module.exports.CREATE_Ax           = CREATE_Ax;
+module.exports.INDEXK              = INDEXK;
+module.exports.ISK                 = ISK;
+module.exports.LFIELDS_PER_FLUSH   = LFIELDS_PER_FLUSH;
+module.exports.MAXARG_A            = MAXARG_A;
+module.exports.MAXARG_Ax           = MAXARG_Ax;
+module.exports.MAXARG_B            = MAXARG_B;
+module.exports.MAXARG_Bx           = MAXARG_Bx;
+module.exports.MAXARG_C            = MAXARG_C;
+module.exports.MAXARG_sBx          = MAXARG_sBx;
+module.exports.NO_REG              = NO_REG;
+module.exports.OpArgK              = OpArgK;
+module.exports.OpArgN              = OpArgN;
+module.exports.OpArgR              = OpArgR;
+module.exports.OpArgU              = OpArgU;
+module.exports.OpCodes             = OpCodes;
+module.exports.OpCodesI            = OpCodesI;
+module.exports.POS_A               = POS_A;
+module.exports.POS_Ax              = POS_Ax;
+module.exports.POS_B               = POS_B;
+module.exports.POS_Bx              = POS_Bx;
+module.exports.POS_C               = POS_C;
+module.exports.POS_OP              = POS_OP;
+module.exports.RKASK               = RKASK;
+module.exports.SETARG_A            = SETARG_A;
+module.exports.SETARG_Ax           = SETARG_Ax;
+module.exports.SETARG_B            = SETARG_B;
+module.exports.SETARG_Bx           = SETARG_Bx;
+module.exports.SETARG_C            = SETARG_C;
+module.exports.SETARG_sBx          = SETARG_sBx;
+module.exports.SIZE_A              = SIZE_A;
+module.exports.SIZE_Ax             = SIZE_Ax;
+module.exports.SIZE_B              = SIZE_B;
+module.exports.SIZE_Bx             = SIZE_Bx;
+module.exports.SIZE_C              = SIZE_C;
+module.exports.SIZE_OP             = SIZE_OP;
+module.exports.fullins             = fullins;
+module.exports.getBMode            = getBMode;
+module.exports.getCMode            = getCMode;
+module.exports.getOpMode           = getOpMode;
+module.exports.iABC                = iABC;
+module.exports.iABx                = iABx;
+module.exports.iAsBx               = iAsBx;
+module.exports.iAx                 = iAx;
+module.exports.testAMode           = testAMode;
+module.exports.testTMode           = testTMode;
\ No newline at end of file