lua/lopcodes.h
Roberto Ierusalimschy 55ac40f859 Cleaning of llimits.h
Several definitions that don't need to be "global" (that is, that
concerns only specific parts of the code) moved out of llimits.h,
to more appropriate places.
2024-06-20 13:43:33 -03:00

406 lines
13 KiB
C

/*
** $Id: lopcodes.h $
** 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 32-bit integers.
All instructions have an opcode in the first 7 bits.
Instructions can have the following formats:
3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0
1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
iABC C(8) | B(8) |k| A(8) | Op(7) |
iABx Bx(17) | A(8) | Op(7) |
iAsBx sBx (signed)(17) | A(8) | Op(7) |
iAx Ax(25) | Op(7) |
isJ sJ (signed)(25) | Op(7) |
A signed argument is represented in excess K: the represented value is
the written unsigned value minus K, where K is half the maximum for the
corresponding unsigned argument.
===========================================================================*/
enum OpMode {iABC, iABx, iAsBx, iAx, isJ}; /* basic instruction formats */
/*
** size and position of opcode arguments.
*/
#define SIZE_C 8
#define SIZE_B 8
#define SIZE_Bx (SIZE_C + SIZE_B + 1)
#define SIZE_A 8
#define SIZE_Ax (SIZE_Bx + SIZE_A)
#define SIZE_sJ (SIZE_Bx + SIZE_A)
#define SIZE_OP 7
#define POS_OP 0
#define POS_A (POS_OP + SIZE_OP)
#define POS_k (POS_A + SIZE_A)
#define POS_B (POS_k + 1)
#define POS_C (POS_B + SIZE_B)
#define POS_Bx POS_k
#define POS_Ax POS_A
#define POS_sJ POS_A
/*
** limits for opcode arguments.
** we use (signed) 'int' to manipulate most arguments,
** so they must fit in ints.
*/
/* Check whether type 'int' has at least 'b' bits ('b' < 32) */
#define L_INTHASBITS(b) ((UINT_MAX >> ((b) - 1)) >= 1)
#if L_INTHASBITS(SIZE_Bx)
#define MAXARG_Bx ((1<<SIZE_Bx)-1)
#else
#define MAXARG_Bx INT_MAX
#endif
#define OFFSET_sBx (MAXARG_Bx>>1) /* 'sBx' is signed */
#if L_INTHASBITS(SIZE_Ax)
#define MAXARG_Ax ((1<<SIZE_Ax)-1)
#else
#define MAXARG_Ax INT_MAX
#endif
#if L_INTHASBITS(SIZE_sJ)
#define MAXARG_sJ ((1 << SIZE_sJ) - 1)
#else
#define MAXARG_sJ INT_MAX
#endif
#define OFFSET_sJ (MAXARG_sJ >> 1)
#define MAXARG_A ((1<<SIZE_A)-1)
#define MAXARG_B ((1<<SIZE_B)-1)
#define MAXARG_C ((1<<SIZE_C)-1)
#define OFFSET_sC (MAXARG_C >> 1)
#define int2sC(i) ((i) + OFFSET_sC)
#define sC2int(i) ((i) - OFFSET_sC)
/* creates a mask with 'n' 1 bits at position 'p' */
#define MASK1(n,p) ((~((~(Instruction)0)<<(n)))<<(p))
/* creates a mask with 'n' 0 bits at position 'p' */
#define MASK0(n,p) (~MASK1(n,p))
/*
** the following macros help to manipulate instructions
*/
#define GET_OPCODE(i) (cast(OpCode, ((i)>>POS_OP) & MASK1(SIZE_OP,0)))
#define SET_OPCODE(i,o) ((i) = (((i)&MASK0(SIZE_OP,POS_OP)) | \
((cast(Instruction, o)<<POS_OP)&MASK1(SIZE_OP,POS_OP))))
#define checkopm(i,m) (getOpMode(GET_OPCODE(i)) == m)
#define getarg(i,pos,size) (cast_int(((i)>>(pos)) & MASK1(size,0)))
#define setarg(i,v,pos,size) ((i) = (((i)&MASK0(size,pos)) | \
((cast(Instruction, v)<<pos)&MASK1(size,pos))))
#define GETARG_A(i) getarg(i, POS_A, SIZE_A)
#define SETARG_A(i,v) setarg(i, v, POS_A, SIZE_A)
#define GETARG_B(i) check_exp(checkopm(i, iABC), getarg(i, POS_B, SIZE_B))
#define GETARG_sB(i) sC2int(GETARG_B(i))
#define SETARG_B(i,v) setarg(i, v, POS_B, SIZE_B)
#define GETARG_C(i) check_exp(checkopm(i, iABC), getarg(i, POS_C, SIZE_C))
#define GETARG_sC(i) sC2int(GETARG_C(i))
#define SETARG_C(i,v) setarg(i, v, POS_C, SIZE_C)
#define TESTARG_k(i) check_exp(checkopm(i, iABC), (cast_int(((i) & (1u << POS_k)))))
#define GETARG_k(i) check_exp(checkopm(i, iABC), getarg(i, POS_k, 1))
#define SETARG_k(i,v) setarg(i, v, POS_k, 1)
#define GETARG_Bx(i) check_exp(checkopm(i, iABx), getarg(i, POS_Bx, SIZE_Bx))
#define SETARG_Bx(i,v) setarg(i, v, POS_Bx, SIZE_Bx)
#define GETARG_Ax(i) check_exp(checkopm(i, iAx), getarg(i, POS_Ax, SIZE_Ax))
#define SETARG_Ax(i,v) setarg(i, v, POS_Ax, SIZE_Ax)
#define GETARG_sBx(i) \
check_exp(checkopm(i, iAsBx), getarg(i, POS_Bx, SIZE_Bx) - OFFSET_sBx)
#define SETARG_sBx(i,b) SETARG_Bx((i),cast_uint((b)+OFFSET_sBx))
#define GETARG_sJ(i) \
check_exp(checkopm(i, isJ), getarg(i, POS_sJ, SIZE_sJ) - OFFSET_sJ)
#define SETARG_sJ(i,j) \
setarg(i, cast_uint((j)+OFFSET_sJ), POS_sJ, SIZE_sJ)
#define CREATE_ABCk(o,a,b,c,k) ((cast(Instruction, o)<<POS_OP) \
| (cast(Instruction, a)<<POS_A) \
| (cast(Instruction, b)<<POS_B) \
| (cast(Instruction, c)<<POS_C) \
| (cast(Instruction, k)<<POS_k))
#define CREATE_ABx(o,a,bc) ((cast(Instruction, o)<<POS_OP) \
| (cast(Instruction, a)<<POS_A) \
| (cast(Instruction, bc)<<POS_Bx))
#define CREATE_Ax(o,a) ((cast(Instruction, o)<<POS_OP) \
| (cast(Instruction, a)<<POS_Ax))
#define CREATE_sJ(o,j,k) ((cast(Instruction, o) << POS_OP) \
| (cast(Instruction, j) << POS_sJ) \
| (cast(Instruction, k) << POS_k))
#if !defined(MAXINDEXRK) /* (for debugging only) */
#define MAXINDEXRK MAXARG_B
#endif
/*
** invalid register that fits in 8 bits
*/
#define NO_REG MAXARG_A
/*
** R[x] - register
** K[x] - constant (in constant table)
** RK(x) == if k(i) then K[x] else R[x]
*/
/*
** Grep "ORDER OP" if you change these enums. Opcodes marked with a (*)
** has extra descriptions in the notes after the enumeration.
*/
typedef enum {
/*----------------------------------------------------------------------
name args description
------------------------------------------------------------------------*/
OP_MOVE,/* A B R[A] := R[B] */
OP_LOADI,/* A sBx R[A] := sBx */
OP_LOADF,/* A sBx R[A] := (lua_Number)sBx */
OP_LOADK,/* A Bx R[A] := K[Bx] */
OP_LOADKX,/* A R[A] := K[extra arg] */
OP_LOADFALSE,/* A R[A] := false */
OP_LFALSESKIP,/*A R[A] := false; pc++ (*) */
OP_LOADTRUE,/* A R[A] := true */
OP_LOADNIL,/* A B R[A], R[A+1], ..., R[A+B] := nil */
OP_GETUPVAL,/* A B R[A] := UpValue[B] */
OP_SETUPVAL,/* A B UpValue[B] := R[A] */
OP_GETTABUP,/* A B C R[A] := UpValue[B][K[C]:shortstring] */
OP_GETTABLE,/* A B C R[A] := R[B][R[C]] */
OP_GETI,/* A B C R[A] := R[B][C] */
OP_GETFIELD,/* A B C R[A] := R[B][K[C]:shortstring] */
OP_SETTABUP,/* A B C UpValue[A][K[B]:shortstring] := RK(C) */
OP_SETTABLE,/* A B C R[A][R[B]] := RK(C) */
OP_SETI,/* A B C R[A][B] := RK(C) */
OP_SETFIELD,/* A B C R[A][K[B]:shortstring] := RK(C) */
OP_NEWTABLE,/* A B C k R[A] := {} */
OP_SELF,/* A B C R[A+1] := R[B]; R[A] := R[B][RK(C):string] */
OP_ADDI,/* A B sC R[A] := R[B] + sC */
OP_ADDK,/* A B C R[A] := R[B] + K[C]:number */
OP_SUBK,/* A B C R[A] := R[B] - K[C]:number */
OP_MULK,/* A B C R[A] := R[B] * K[C]:number */
OP_MODK,/* A B C R[A] := R[B] % K[C]:number */
OP_POWK,/* A B C R[A] := R[B] ^ K[C]:number */
OP_DIVK,/* A B C R[A] := R[B] / K[C]:number */
OP_IDIVK,/* A B C R[A] := R[B] // K[C]:number */
OP_BANDK,/* A B C R[A] := R[B] & K[C]:integer */
OP_BORK,/* A B C R[A] := R[B] | K[C]:integer */
OP_BXORK,/* A B C R[A] := R[B] ~ K[C]:integer */
OP_SHRI,/* A B sC R[A] := R[B] >> sC */
OP_SHLI,/* A B sC R[A] := sC << R[B] */
OP_ADD,/* A B C R[A] := R[B] + R[C] */
OP_SUB,/* A B C R[A] := R[B] - R[C] */
OP_MUL,/* A B C R[A] := R[B] * R[C] */
OP_MOD,/* A B C R[A] := R[B] % R[C] */
OP_POW,/* A B C R[A] := R[B] ^ R[C] */
OP_DIV,/* A B C R[A] := R[B] / R[C] */
OP_IDIV,/* A B C R[A] := R[B] // R[C] */
OP_BAND,/* A B C R[A] := R[B] & R[C] */
OP_BOR,/* A B C R[A] := R[B] | R[C] */
OP_BXOR,/* A B C R[A] := R[B] ~ R[C] */
OP_SHL,/* A B C R[A] := R[B] << R[C] */
OP_SHR,/* A B C R[A] := R[B] >> R[C] */
OP_MMBIN,/* A B C call C metamethod over R[A] and R[B] (*) */
OP_MMBINI,/* A sB C k call C metamethod over R[A] and sB */
OP_MMBINK,/* A B C k call C metamethod over R[A] and K[B] */
OP_UNM,/* A B R[A] := -R[B] */
OP_BNOT,/* A B R[A] := ~R[B] */
OP_NOT,/* A B R[A] := not R[B] */
OP_LEN,/* A B R[A] := #R[B] (length operator) */
OP_CONCAT,/* A B R[A] := R[A].. ... ..R[A + B - 1] */
OP_CLOSE,/* A close all upvalues >= R[A] */
OP_TBC,/* A mark variable A "to be closed" */
OP_JMP,/* sJ pc += sJ */
OP_EQ,/* A B k if ((R[A] == R[B]) ~= k) then pc++ */
OP_LT,/* A B k if ((R[A] < R[B]) ~= k) then pc++ */
OP_LE,/* A B k if ((R[A] <= R[B]) ~= k) then pc++ */
OP_EQK,/* A B k if ((R[A] == K[B]) ~= k) then pc++ */
OP_EQI,/* A sB k if ((R[A] == sB) ~= k) then pc++ */
OP_LTI,/* A sB k if ((R[A] < sB) ~= k) then pc++ */
OP_LEI,/* A sB k if ((R[A] <= sB) ~= k) then pc++ */
OP_GTI,/* A sB k if ((R[A] > sB) ~= k) then pc++ */
OP_GEI,/* A sB k if ((R[A] >= sB) ~= k) then pc++ */
OP_TEST,/* A k if (not R[A] == k) then pc++ */
OP_TESTSET,/* A B k if (not R[B] == k) then pc++ else R[A] := R[B] (*) */
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 k return R[A](R[A+1], ... ,R[A+B-1]) */
OP_RETURN,/* A B C k return R[A], ... ,R[A+B-2] (see note) */
OP_RETURN0,/* return */
OP_RETURN1,/* A return R[A] */
OP_FORLOOP,/* A Bx update counters; if loop continues then pc-=Bx; */
OP_FORPREP,/* A Bx <check values and prepare counters>;
if not to run then pc+=Bx+1; */
OP_TFORPREP,/* A Bx create upvalue for R[A + 3]; pc+=Bx */
OP_TFORCALL,/* A C R[A+4], ... ,R[A+3+C] := R[A](R[A+1], R[A+2]); */
OP_TFORLOOP,/* A Bx if R[A+2] ~= nil then { R[A]=R[A+2]; pc -= Bx } */
OP_SETLIST,/* A B C k R[A][C+i] := R[A+i], 1 <= i <= B */
OP_CLOSURE,/* A Bx R[A] := closure(KPROTO[Bx]) */
OP_VARARG,/* A C R[A], R[A+1], ..., R[A+C-2] = vararg */
OP_VARARGPREP,/*A (adjust vararg parameters) */
OP_EXTRAARG/* Ax extra (larger) argument for previous opcode */
} OpCode;
#define NUM_OPCODES ((int)(OP_EXTRAARG) + 1)
/*===========================================================================
Notes:
(*) Opcode OP_LFALSESKIP is used to convert a condition to a boolean
value, in a code equivalent to (not cond ? false : true). (It
produces false and skips the next instruction producing true.)
(*) Opcodes OP_MMBIN and variants follow each arithmetic and
bitwise opcode. If the operation succeeds, it skips this next
opcode. Otherwise, this opcode calls the corresponding metamethod.
(*) Opcode OP_TESTSET is used in short-circuit expressions that need
both to jump and to produce a value, such as (a = b or c).
(*) In OP_CALL, if (B == 0) then B = top - A. If (C == 0), then
'top' is set to last_result+1, so next open instruction (OP_CALL,
OP_RETURN*, OP_SETLIST) may use 'top'.
(*) In OP_VARARG, if (C == 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_LOADKX and OP_NEWTABLE, the next instruction is always
OP_EXTRAARG.
(*) In OP_SETLIST, if (B == 0) then real B = 'top'; if k, then
real C = EXTRAARG _ C (the bits of EXTRAARG concatenated with the
bits of C).
(*) In OP_NEWTABLE, B is log2 of the hash size (which is always a
power of 2) plus 1, or zero for size zero. If not k, the array size
is C. Otherwise, the array size is EXTRAARG _ C.
(*) For comparisons, k specifies what condition the test should accept
(true or false).
(*) In OP_MMBINI/OP_MMBINK, k means the arguments were flipped
(the constant is the first operand).
(*) All 'skips' (pc++) assume that next instruction is a jump.
(*) In instructions OP_RETURN/OP_TAILCALL, 'k' specifies that the
function builds upvalues, which may need to be closed. C > 0 means
the function is vararg, so that its 'func' must be corrected before
returning; in this case, (C - 1) is its number of fixed parameters.
(*) In comparisons with an immediate operand, C signals whether the
original operand was a float. (It must be corrected in case of
metamethods.)
===========================================================================*/
/*
** masks for instruction properties. The format is:
** bits 0-2: op mode
** bit 3: instruction set register A
** bit 4: operator is a test (next instruction must be a jump)
** bit 5: instruction uses 'L->top' set by previous instruction (when B == 0)
** bit 6: instruction sets 'L->top' for next instruction (when C == 0)
** bit 7: instruction is an MM instruction (call a metamethod)
*/
LUAI_DDEC(const lu_byte luaP_opmodes[NUM_OPCODES];)
#define getOpMode(m) (cast(enum OpMode, luaP_opmodes[m] & 7))
#define testAMode(m) (luaP_opmodes[m] & (1 << 3))
#define testTMode(m) (luaP_opmodes[m] & (1 << 4))
#define testITMode(m) (luaP_opmodes[m] & (1 << 5))
#define testOTMode(m) (luaP_opmodes[m] & (1 << 6))
#define testMMMode(m) (luaP_opmodes[m] & (1 << 7))
/* "out top" (set top for next instruction) */
#define isOT(i) \
((testOTMode(GET_OPCODE(i)) && GETARG_C(i) == 0) || \
GET_OPCODE(i) == OP_TAILCALL)
/* "in top" (uses top from previous instruction) */
#define isIT(i) (testITMode(GET_OPCODE(i)) && GETARG_B(i) == 0)
#define opmode(mm,ot,it,t,a,m) \
(((mm) << 7) | ((ot) << 6) | ((it) << 5) | ((t) << 4) | ((a) << 3) | (m))
/* number of list items to accumulate before a SETLIST instruction */
#define LFIELDS_PER_FLUSH 50
#endif