/* ** \$Id: lopcodes.h,v 1.142 2011/07/15 12:50:29 roberto Exp \$ ** Opcodes for Lua virtual machine ** See Copyright Notice in lua.h */ #ifndef lopcodes_h #define lopcodes_h #include "llimits.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 'Ax' : 26 bits ('A', 'B', and 'C' together) `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. ===========================================================================*/ enum OpMode {iABC, iABx, iAsBx, iAx}; /* basic instruction format */ /* ** size and position of opcode arguments. */ #define SIZE_C 9 #define SIZE_B 9 #define SIZE_Bx (SIZE_C + SIZE_B) #define SIZE_A 8 #define SIZE_Ax (SIZE_C + SIZE_B + SIZE_A) #define SIZE_OP 6 #define POS_OP 0 #define POS_A (POS_OP + SIZE_OP) #define POS_C (POS_A + SIZE_A) #define POS_B (POS_C + SIZE_C) #define POS_Bx POS_C #define POS_Ax POS_A /* ** limits for opcode arguments. ** we use (signed) int to manipulate most arguments, ** so they must fit in LUAI_BITSINT-1 bits (-1 for sign) */ #if SIZE_Bx < LUAI_BITSINT-1 #define MAXARG_Bx ((1<>1) /* `sBx' is signed */ #else #define MAXARG_Bx MAX_INT #define MAXARG_sBx MAX_INT #endif #if SIZE_Ax < LUAI_BITSINT-1 #define MAXARG_Ax ((1<>POS_OP) & MASK1(SIZE_OP,0))) #define SET_OPCODE(i,o) ((i) = (((i)&MASK0(SIZE_OP,POS_OP)) | \ ((cast(Instruction, o)<>pos) & MASK1(size,0))) #define setarg(i,v,pos,size) ((i) = (((i)&MASK0(size,pos)) | \ ((cast(Instruction, v)<= R(A) + 1 */ OP_EQ,/* A B C if ((RK(B) == RK(C)) ~= A) then pc++ */ OP_LT,/* A B C if ((RK(B) < RK(C)) ~= A) then pc++ */ OP_LE,/* A B C if ((RK(B) <= RK(C)) ~= A) then pc++ */ OP_TEST,/* A C if not (R(A) <=> C) then pc++ */ OP_TESTSET,/* A B C if (R(B) <=> C) then R(A) := R(B) else pc++ */ OP_CALL,/* A B C R(A), ... ,R(A+C-2) := R(A)(R(A+1), ... ,R(A+B-1)) */ OP_TAILCALL,/* A B C return R(A)(R(A+1), ... ,R(A+B-1)) */ OP_RETURN,/* A B return R(A), ... ,R(A+B-2) (see note) */ OP_FORLOOP,/* A sBx R(A)+=R(A+2); if R(A) > 4) & 3)) #define getCMode(m) (cast(enum OpArgMask, (luaP_opmodes[m] >> 2) & 3)) #define testAMode(m) (luaP_opmodes[m] & (1 << 6)) #define testTMode(m) (luaP_opmodes[m] & (1 << 7)) LUAI_DDEC const char *const luaP_opnames[NUM_OPCODES+1]; /* opcode names */ /* number of list items to accumulate before a SETLIST instruction */ #define LFIELDS_PER_FLUSH 50 #endif