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https://github.com/lua/lua.git
synced 2024-11-27 04:03:54 +08:00
New implementation for constants
VLOCAL expressions keep a reference to their corresponding 'Vardesc',
and 'Upvaldesc' (for upvalues) has a field 'ro' (read-only). So, it is
easier to check whether a variable is read-only. The decoupling in
VLOCAL between 'vidx' ('Vardesc' index) and 'sidx' (stack index)
should also help the forthcoming implementation of compile-time
constant propagation.
This commit is contained in:
Roberto Ierusalimschy
parent
e888976bc6
commit
54f7b46c1e
60
lcode.c
60
lcode.c
@ -52,7 +52,7 @@ l_noret luaK_semerror (LexState *ls, const char *msg) {
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** If expression is a numeric constant, fills 'v' with its value
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** and returns 1. Otherwise, returns 0.
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*/
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int luaK_tonumeral (FuncState *fs, const expdesc *e, TValue *v) {
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static int tonumeral (const expdesc *e, TValue *v) {
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if (hasjumps(e))
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return 0; /* not a numeral */
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switch (e->k) {
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@ -62,41 +62,11 @@ int luaK_tonumeral (FuncState *fs, const expdesc *e, TValue *v) {
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case VKFLT:
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if (v) setfltvalue(v, e->u.nval);
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return 1;
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case VUPVAL: { /* may be a constant */
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Vardesc *vd = luaY_getvardesc(&fs, e);
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if (v && vd && !ttisnil(&vd->val)) {
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setobj(fs->ls->L, v, &vd->val);
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return 1;
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} /* else */
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} /* FALLTHROUGH */
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default: return 0;
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}
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}
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/*
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** If expression 'e' is a constant, change 'e' to represent
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** the constant value.
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*/
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static int const2exp (FuncState *fs, expdesc *e) {
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Vardesc *vd = luaY_getvardesc(&fs, e);
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if (vd) {
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TValue *v = &vd->val;
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switch (ttypetag(v)) {
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case LUA_TNUMINT:
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e->k = VKINT;
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e->u.ival = ivalue(v);
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return 1;
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case LUA_TNUMFLT:
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e->k = VKFLT;
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e->u.nval = fltvalue(v);
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return 1;
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}
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}
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return 0;
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}
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/*
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** Return the previous instruction of the current code. If there
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** may be a jump target between the current instruction and the
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@ -708,15 +678,13 @@ void luaK_setoneret (FuncState *fs, expdesc *e) {
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void luaK_dischargevars (FuncState *fs, expdesc *e) {
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switch (e->k) {
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case VLOCAL: { /* already in a register */
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e->u.info = e->u.var.idx;
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e->u.info = e->u.var.sidx;
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e->k = VNONRELOC; /* becomes a non-relocatable value */
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break;
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}
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case VUPVAL: { /* move value to some (pending) register */
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if (!const2exp(fs, e)) {
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e->u.info = luaK_codeABC(fs, OP_GETUPVAL, 0, e->u.var.idx, 0);
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e->k = VRELOC;
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}
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e->u.info = luaK_codeABC(fs, OP_GETUPVAL, 0, e->u.info, 0);
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e->k = VRELOC;
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break;
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}
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case VINDEXUP: {
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@ -971,12 +939,12 @@ void luaK_storevar (FuncState *fs, expdesc *var, expdesc *ex) {
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switch (var->k) {
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case VLOCAL: {
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freeexp(fs, ex);
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exp2reg(fs, ex, var->u.var.idx); /* compute 'ex' into proper place */
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exp2reg(fs, ex, var->u.var.sidx); /* compute 'ex' into proper place */
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return;
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}
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case VUPVAL: {
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int e = luaK_exp2anyreg(fs, ex);
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luaK_codeABC(fs, OP_SETUPVAL, e, var->u.var.idx, 0);
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luaK_codeABC(fs, OP_SETUPVAL, e, var->u.info, 0);
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break;
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}
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case VINDEXUP: {
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@ -1203,13 +1171,13 @@ void luaK_indexed (FuncState *fs, expdesc *t, expdesc *k) {
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if (t->k == VUPVAL && !isKstr(fs, k)) /* upvalue indexed by non string? */
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luaK_exp2anyreg(fs, t); /* put it in a register */
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if (t->k == VUPVAL) {
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t->u.ind.t = t->u.var.idx; /* upvalue index */
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t->u.ind.t = t->u.info; /* upvalue index */
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t->u.ind.idx = k->u.info; /* literal string */
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t->k = VINDEXUP;
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}
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else {
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/* register index of the table */
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t->u.ind.t = (t->k == VLOCAL) ? t->u.var.idx: t->u.info;
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t->u.ind.t = (t->k == VLOCAL) ? t->u.var.sidx: t->u.info;
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if (isKstr(fs, k)) {
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t->u.ind.idx = k->u.info; /* literal string */
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t->k = VINDEXSTR;
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@ -1252,9 +1220,7 @@ static int validop (int op, TValue *v1, TValue *v2) {
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static int constfolding (FuncState *fs, int op, expdesc *e1,
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const expdesc *e2) {
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TValue v1, v2, res;
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if (!luaK_tonumeral(fs, e1, &v1) ||
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!luaK_tonumeral(fs, e2, &v2) ||
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!validop(op, &v1, &v2))
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if (!tonumeral(e1, &v1) || !tonumeral(e2, &v2) || !validop(op, &v1, &v2))
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return 0; /* non-numeric operands or not safe to fold */
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luaO_rawarith(fs->ls->L, op, &v1, &v2, &res); /* does operation */
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if (ttisinteger(&res)) {
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@ -1341,7 +1307,7 @@ static void codearith (FuncState *fs, OpCode op,
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expdesc *e1, expdesc *e2, int flip, int line) {
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if (isSCint(e2)) /* immediate operand? */
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codebini(fs, cast(OpCode, op - OP_ADD + OP_ADDI), e1, e2, flip, line);
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else if (luaK_tonumeral(fs, e2, NULL) && luaK_exp2K(fs, e2)) { /* K operand? */
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else if (tonumeral(e2, NULL) && luaK_exp2K(fs, e2)) { /* K operand? */
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int v2 = e2->u.info; /* K index */
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op = cast(OpCode, op - OP_ADD + OP_ADDK);
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finishbinexpval(fs, e1, e2, op, v2, flip, line);
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@ -1362,7 +1328,7 @@ static void codearith (FuncState *fs, OpCode op,
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static void codecommutative (FuncState *fs, OpCode op,
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expdesc *e1, expdesc *e2, int line) {
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int flip = 0;
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if (luaK_tonumeral(fs, e1, NULL)) { /* is first operand a numeric constant? */
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if (tonumeral(e1, NULL)) { /* is first operand a numeric constant? */
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swapexps(e1, e2); /* change order */
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flip = 1;
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}
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@ -1519,13 +1485,13 @@ void luaK_infix (FuncState *fs, BinOpr op, expdesc *v) {
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case OPR_MOD: case OPR_POW:
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case OPR_BAND: case OPR_BOR: case OPR_BXOR:
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case OPR_SHL: case OPR_SHR: {
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if (!luaK_tonumeral(fs, v, NULL))
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if (!tonumeral(v, NULL))
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luaK_exp2anyreg(fs, v);
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/* else keep numeral, which may be folded with 2nd operand */
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break;
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}
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case OPR_EQ: case OPR_NE: {
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if (!luaK_tonumeral(fs, v, NULL))
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if (!tonumeral(v, NULL))
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luaK_exp2RK(fs, v);
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/* else keep numeral, which may be an immediate operand */
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break;
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1
lcode.h
1
lcode.h
@ -51,7 +51,6 @@ typedef enum UnOpr { OPR_MINUS, OPR_BNOT, OPR_NOT, OPR_LEN, OPR_NOUNOPR } UnOpr;
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#define luaK_jumpto(fs,t) luaK_patchlist(fs, luaK_jump(fs), t)
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LUAI_FUNC int luaK_tonumeral (FuncState *fs, const expdesc *e, TValue *v);
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LUAI_FUNC int luaK_codeABx (FuncState *fs, OpCode o, int A, unsigned int Bx);
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LUAI_FUNC int luaK_codeAsBx (FuncState *fs, OpCode o, int A, int Bx);
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LUAI_FUNC int luaK_codeABCk (FuncState *fs, OpCode o, int A,
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1
ldump.c
1
ldump.c
@ -149,6 +149,7 @@ static void DumpUpvalues (const Proto *f, DumpState *D) {
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for (i = 0; i < n; i++) {
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DumpByte(f->upvalues[i].instack, D);
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DumpByte(f->upvalues[i].idx, D);
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DumpByte(f->upvalues[i].ro, D);
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}
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}
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@ -460,6 +460,7 @@ typedef struct Upvaldesc {
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TString *name; /* upvalue name (for debug information) */
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lu_byte instack; /* whether it is in stack (register) */
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lu_byte idx; /* index of upvalue (in stack or in outer function's list) */
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lu_byte ro; /* true if upvalue is read-only (const) */
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} Upvaldesc;
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158
lparser.c
158
lparser.c
@ -156,13 +156,6 @@ static void init_exp (expdesc *e, expkind k, int i) {
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}
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static void init_var (expdesc *e, expkind k, int i) {
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e->f = e->t = NO_JUMP;
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e->k = k;
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e->u.var.idx = i;
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}
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static void codestring (LexState *ls, expdesc *e, TString *s) {
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init_exp(e, VK, luaK_stringK(ls->fs, s));
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}
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@ -177,16 +170,15 @@ static void codename (LexState *ls, expdesc *e) {
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** Register a new local variable in the active 'Proto' (for debug
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** information).
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*/
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static int registerlocalvar (LexState *ls, TString *varname) {
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FuncState *fs = ls->fs;
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static int registerlocalvar (lua_State *L, FuncState *fs, TString *varname) {
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Proto *f = fs->f;
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int oldsize = f->sizelocvars;
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luaM_growvector(ls->L, f->locvars, fs->nlocvars, f->sizelocvars,
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luaM_growvector(L, f->locvars, fs->nlocvars, f->sizelocvars,
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LocVar, SHRT_MAX, "local variables");
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while (oldsize < f->sizelocvars)
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f->locvars[oldsize++].varname = NULL;
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f->locvars[fs->nlocvars].varname = varname;
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luaC_objbarrier(ls->L, f, varname);
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luaC_objbarrier(L, f, varname);
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return fs->nlocvars++;
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}
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@ -195,18 +187,19 @@ static int registerlocalvar (LexState *ls, TString *varname) {
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** Create a new local variable with the given 'name'.
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*/
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static Vardesc *new_localvar (LexState *ls, TString *name) {
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lua_State *L = ls->L;
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FuncState *fs = ls->fs;
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Dyndata *dyd = ls->dyd;
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Vardesc *var;
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int reg = registerlocalvar(ls, name);
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int reg = registerlocalvar(L, fs, name);
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checklimit(fs, dyd->actvar.n + 1 - fs->firstlocal,
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MAXVARS, "local variables");
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luaM_growvector(ls->L, dyd->actvar.arr, dyd->actvar.n + 1,
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dyd->actvar.size, Vardesc, MAX_INT, "local variables");
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luaM_growvector(L, dyd->actvar.arr, dyd->actvar.n + 1,
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dyd->actvar.size, Vardesc, USHRT_MAX, "local variables");
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var = &dyd->actvar.arr[dyd->actvar.n++];
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var->idx = cast(short, reg);
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var->pidx = cast(short, reg);
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var->ro = 0;
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setnilvalue(&var->val);
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setnilvalue(var);
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return var;
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}
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@ -223,50 +216,47 @@ static Vardesc *getlocalvardesc (FuncState *fs, int i) {
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return &fs->ls->dyd->actvar.arr[fs->firstlocal + i];
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}
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/*
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** Get the debug-information entry for current variable 'i'.
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*/
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static LocVar *getlocvar (FuncState *fs, int i) {
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int idx = getlocalvardesc(fs, i)->idx;
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static LocVar *localdebuginfo (FuncState *fs, int i) {
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int idx = getlocalvardesc(fs, i)->pidx;
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lua_assert(idx < fs->nlocvars);
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return &fs->f->locvars[idx];
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}
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/*
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** Return the "variable description" (Vardesc) of a given
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** local variable and update 'fs' to point to the function
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** where that variable was defined. Return NULL if expression
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** is neither a local variable nor an upvalue.
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*/
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Vardesc *luaY_getvardesc (FuncState **fs, const expdesc *e) {
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if (e->k == VLOCAL)
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return getlocalvardesc(*fs, e->u.var.idx);
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else if (e->k != VUPVAL)
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return NULL; /* not a local variable */
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else { /* upvalue: must go up all levels up to the original local */
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int idx = e->u.var.idx;
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for (;;) {
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Upvaldesc *up = &(*fs)->f->upvalues[idx];
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*fs = (*fs)->prev; /* must look at the previous level */
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idx = up->idx; /* at this index */
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if (*fs == NULL) /* no more levels? (can happen only with _ENV) */
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return NULL;
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else if (up->instack) /* got to the original level? */
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return getlocalvardesc(*fs, idx);
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/* else repeat for previous level */
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}
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}
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static void init_var (FuncState *fs, expdesc *e, int i) {
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e->f = e->t = NO_JUMP;
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e->k = VLOCAL;
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e->u.var.vidx = i;
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e->u.var.sidx = getlocalvardesc(fs, i)->sidx;
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}
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static void check_readonly (LexState *ls, expdesc *e) {
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FuncState *fs = ls->fs;
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Vardesc *vardesc = luaY_getvardesc(&fs, e);
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if (vardesc && vardesc->ro) { /* is variable local and const? */
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TString *varname = NULL; /* to be set if variable is const */
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switch (e->k) {
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case VLOCAL: {
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Vardesc *vardesc = getlocalvardesc(fs, e->u.var.vidx);
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if (vardesc->ro)
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varname = fs->f->locvars[vardesc->pidx].varname;
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break;
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}
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case VUPVAL: {
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Upvaldesc *up = &fs->f->upvalues[e->u.info];
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if (up->ro)
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varname = up->name;
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break;
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}
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default:
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return; /* other cases cannot be read-only */
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}
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if (varname) {
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const char *msg = luaO_pushfstring(ls->L,
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"attempt to assign to const variable '%s'",
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getstr(fs->f->locvars[vardesc->idx].varname));
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"attempt to assign to const variable '%s'", getstr(varname));
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luaK_semerror(ls, msg); /* error */
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}
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}
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@ -274,13 +264,15 @@ static void check_readonly (LexState *ls, expdesc *e) {
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/*
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** Start the scope for the last 'nvars' created variables.
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** (debug info.)
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*/
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static void adjustlocalvars (LexState *ls, int nvars) {
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FuncState *fs = ls->fs;
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fs->nactvar = cast_byte(fs->nactvar + nvars);
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for (; nvars; nvars--) {
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getlocvar(fs, fs->nactvar - nvars)->startpc = fs->pc;
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int i;
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for (i = 0; i < nvars; i++) {
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int varidx = fs->nactvar++;
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Vardesc *var = getlocalvardesc(fs, varidx);
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var->sidx = varidx;
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fs->f->locvars[var->pidx].startpc = fs->pc;
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}
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}
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@ -292,7 +284,7 @@ static void adjustlocalvars (LexState *ls, int nvars) {
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static void removevars (FuncState *fs, int tolevel) {
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fs->ls->dyd->actvar.n -= (fs->nactvar - tolevel);
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while (fs->nactvar > tolevel)
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getlocvar(fs, --fs->nactvar)->endpc = fs->pc;
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localdebuginfo(fs, --fs->nactvar)->endpc = fs->pc;
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}
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@ -310,7 +302,7 @@ static int searchupvalue (FuncState *fs, TString *name) {
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}
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static int newupvalue (FuncState *fs, TString *name, expdesc *v) {
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static Upvaldesc *allocupvalue (FuncState *fs) {
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Proto *f = fs->f;
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int oldsize = f->sizeupvalues;
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checklimit(fs, fs->nups + 1, MAXUPVAL, "upvalues");
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@ -318,11 +310,28 @@ static int newupvalue (FuncState *fs, TString *name, expdesc *v) {
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Upvaldesc, MAXUPVAL, "upvalues");
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while (oldsize < f->sizeupvalues)
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f->upvalues[oldsize++].name = NULL;
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f->upvalues[fs->nups].instack = (v->k == VLOCAL);
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f->upvalues[fs->nups].idx = cast_byte(v->u.var.idx);
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f->upvalues[fs->nups].name = name;
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luaC_objbarrier(fs->ls->L, f, name);
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return fs->nups++;
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return &f->upvalues[fs->nups++];
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}
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static int newupvalue (FuncState *fs, TString *name, expdesc *v) {
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Upvaldesc *up = allocupvalue(fs);
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FuncState *prev = fs->prev;
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if (v->k == VLOCAL) {
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up->instack = 1;
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up->idx = v->u.var.sidx;
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up->ro = getlocalvardesc(prev, v->u.var.vidx)->ro;
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lua_assert(eqstr(name, localdebuginfo(prev, v->u.var.vidx)->varname));
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}
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else {
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up->instack = 0;
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up->idx = cast_byte(v->u.info);
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up->ro = prev->f->upvalues[v->u.info].ro;
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lua_assert(eqstr(name, prev->f->upvalues[v->u.info].name));
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}
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up->name = name;
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luaC_objbarrier(fs->ls->L, fs->f, name);
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return fs->nups - 1;
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}
|
||||
|
||||
|
||||
@ -333,7 +342,7 @@ static int newupvalue (FuncState *fs, TString *name, expdesc *v) {
|
||||
static int searchvar (FuncState *fs, TString *n) {
|
||||
int i;
|
||||
for (i = cast_int(fs->nactvar) - 1; i >= 0; i--) {
|
||||
if (eqstr(n, getlocvar(fs, i)->varname))
|
||||
if (eqstr(n, localdebuginfo(fs, i)->varname))
|
||||
return i;
|
||||
}
|
||||
return -1; /* not found */
|
||||
@ -364,9 +373,9 @@ static void singlevaraux (FuncState *fs, TString *n, expdesc *var, int base) {
|
||||
else {
|
||||
int v = searchvar(fs, n); /* look up locals at current level */
|
||||
if (v >= 0) { /* found? */
|
||||
init_var(var, VLOCAL, v); /* variable is local */
|
||||
init_var(fs, var, v); /* variable is local */
|
||||
if (!base)
|
||||
markupval(fs, v); /* local will be used as an upval */
|
||||
markupval(fs, var->u.var.sidx); /* local will be used as an upval */
|
||||
}
|
||||
else { /* not found as local at current level; try upvalues */
|
||||
int idx = searchupvalue(fs, n); /* try existing upvalues */
|
||||
@ -377,7 +386,7 @@ static void singlevaraux (FuncState *fs, TString *n, expdesc *var, int base) {
|
||||
/* else was LOCAL or UPVAL */
|
||||
idx = newupvalue(fs, n, var); /* will be a new upvalue */
|
||||
}
|
||||
init_var(var, VUPVAL, idx); /* new or old upvalue */
|
||||
init_exp(var, VUPVAL, idx); /* new or old upvalue */
|
||||
}
|
||||
}
|
||||
}
|
||||
@ -440,7 +449,7 @@ static void adjust_assign (LexState *ls, int nvars, int nexps, expdesc *e) {
|
||||
** local variable.
|
||||
*/
|
||||
static l_noret jumpscopeerror (LexState *ls, Labeldesc *gt) {
|
||||
const char *varname = getstr(getlocvar(ls->fs, gt->nactvar)->varname);
|
||||
const char *varname = getstr(localdebuginfo(ls->fs, gt->nactvar)->varname);
|
||||
const char *msg = "<goto %s> at line %d jumps into the scope of local '%s'";
|
||||
msg = luaO_pushfstring(ls->L, msg, getstr(gt->name), gt->line, varname);
|
||||
luaK_semerror(ls, msg); /* raise the error */
|
||||
@ -1259,20 +1268,20 @@ static void check_conflict (LexState *ls, struct LHS_assign *lh, expdesc *v) {
|
||||
for (; lh; lh = lh->prev) { /* check all previous assignments */
|
||||
if (vkisindexed(lh->v.k)) { /* assignment to table field? */
|
||||
if (lh->v.k == VINDEXUP) { /* is table an upvalue? */
|
||||
if (v->k == VUPVAL && lh->v.u.ind.t == v->u.var.idx) {
|
||||
if (v->k == VUPVAL && lh->v.u.ind.t == v->u.info) {
|
||||
conflict = 1; /* table is the upvalue being assigned now */
|
||||
lh->v.k = VINDEXSTR;
|
||||
lh->v.u.ind.t = extra; /* assignment will use safe copy */
|
||||
}
|
||||
}
|
||||
else { /* table is a register */
|
||||
if (v->k == VLOCAL && lh->v.u.ind.t == v->u.var.idx) {
|
||||
if (v->k == VLOCAL && lh->v.u.ind.t == v->u.var.sidx) {
|
||||
conflict = 1; /* table is the local being assigned now */
|
||||
lh->v.u.ind.t = extra; /* assignment will use safe copy */
|
||||
}
|
||||
/* is index the local being assigned? */
|
||||
if (lh->v.k == VINDEXED && v->k == VLOCAL &&
|
||||
lh->v.u.ind.idx == v->u.var.idx) {
|
||||
lh->v.u.ind.idx == v->u.var.sidx) {
|
||||
conflict = 1;
|
||||
lh->v.u.ind.idx = extra; /* previous assignment will use safe copy */
|
||||
}
|
||||
@ -1281,14 +1290,16 @@ static void check_conflict (LexState *ls, struct LHS_assign *lh, expdesc *v) {
|
||||
}
|
||||
if (conflict) {
|
||||
/* copy upvalue/local value to a temporary (in position 'extra') */
|
||||
OpCode op = (v->k == VLOCAL) ? OP_MOVE : OP_GETUPVAL;
|
||||
luaK_codeABC(fs, op, extra, v->u.var.idx, 0);
|
||||
if (v->k == VLOCAL)
|
||||
luaK_codeABC(fs, OP_MOVE, extra, v->u.var.sidx, 0);
|
||||
else
|
||||
luaK_codeABC(fs, OP_GETUPVAL, extra, v->u.info, 0);
|
||||
luaK_reserveregs(fs, 1);
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
** Parse and compile a mulitple assignment. The first "variable"
|
||||
** Parse and compile a multiple assignment. The first "variable"
|
||||
** (a 'suffixedexp') was already read by the caller.
|
||||
**
|
||||
** assignment -> suffixedexp restassign
|
||||
@ -1652,7 +1663,7 @@ static void localfunc (LexState *ls) {
|
||||
adjustlocalvars(ls, 1); /* enter its scope */
|
||||
body(ls, &b, 0, ls->linenumber); /* function created in next register */
|
||||
/* debug information will only see the variable after this point! */
|
||||
getlocvar(fs, b.u.info)->startpc = fs->pc;
|
||||
localdebuginfo(fs, b.u.info)->startpc = fs->pc;
|
||||
}
|
||||
|
||||
|
||||
@ -1870,11 +1881,14 @@ static void statement (LexState *ls) {
|
||||
*/
|
||||
static void mainfunc (LexState *ls, FuncState *fs) {
|
||||
BlockCnt bl;
|
||||
expdesc v;
|
||||
Upvaldesc *env;
|
||||
open_func(ls, fs, &bl);
|
||||
setvararg(fs, 0); /* main function is always declared vararg */
|
||||
init_var(&v, VLOCAL, 0); /* create and... */
|
||||
newupvalue(fs, ls->envn, &v); /* ...set environment upvalue */
|
||||
env = allocupvalue(fs); /* ...set environment upvalue */
|
||||
env->instack = 1;
|
||||
env->idx = 0;
|
||||
env->ro = 0;
|
||||
env->name = ls->envn;
|
||||
luaX_next(ls); /* read first token */
|
||||
statlist(ls); /* parse main body */
|
||||
check(ls, TK_EOS);
|
||||
|
||||
16
lparser.h
16
lparser.h
@ -33,8 +33,9 @@ typedef enum {
|
||||
VKINT, /* integer constant; nval = numerical integer value */
|
||||
VNONRELOC, /* expression has its value in a fixed register;
|
||||
info = result register */
|
||||
VLOCAL, /* local variable; var.idx = local register */
|
||||
VUPVAL, /* upvalue variable; var.idx = index of upvalue in 'upvalues' */
|
||||
VLOCAL, /* local variable; var.ridx = local register;
|
||||
var.vidx = index in 'actvar.arr' */
|
||||
VUPVAL, /* upvalue variable; info = index of upvalue in 'upvalues' */
|
||||
VINDEXED, /* indexed variable;
|
||||
ind.t = table register;
|
||||
ind.idx = key's R index */
|
||||
@ -70,8 +71,9 @@ typedef struct expdesc {
|
||||
short idx; /* index (R or "long" K) */
|
||||
lu_byte t; /* table (register or upvalue) */
|
||||
} ind;
|
||||
struct { /* for local variables and upvalues */
|
||||
lu_byte idx; /* index of the variable */
|
||||
struct { /* for local variables */
|
||||
lu_byte sidx; /* index in the stack */
|
||||
unsigned short vidx; /* index in 'actvar.arr' */
|
||||
} var;
|
||||
} u;
|
||||
int t; /* patch list of 'exit when true' */
|
||||
@ -81,9 +83,10 @@ typedef struct expdesc {
|
||||
|
||||
/* description of an active local variable */
|
||||
typedef struct Vardesc {
|
||||
TValue val; /* constant value (if variable is 'const') */
|
||||
short idx; /* index of the variable in the Proto's 'locvars' array */
|
||||
TValuefields; /* constant value (if variable is 'const') */
|
||||
lu_byte ro; /* true if variable is 'const' */
|
||||
lu_byte sidx; /* index of the variable in the stack */
|
||||
short pidx; /* index of the variable in the Proto's 'locvars' array */
|
||||
} Vardesc;
|
||||
|
||||
|
||||
@ -144,7 +147,6 @@ typedef struct FuncState {
|
||||
} FuncState;
|
||||
|
||||
|
||||
LUAI_FUNC Vardesc *luaY_getvardesc (FuncState **fs, const expdesc *e);
|
||||
LUAI_FUNC LClosure *luaY_parser (lua_State *L, ZIO *z, Mbuffer *buff,
|
||||
Dyndata *dyd, const char *name, int firstchar);
|
||||
|
||||
|
||||
@ -203,6 +203,7 @@ static void LoadUpvalues (LoadState *S, Proto *f) {
|
||||
for (i = 0; i < n; i++) {
|
||||
f->upvalues[i].instack = LoadByte(S);
|
||||
f->upvalues[i].idx = LoadByte(S);
|
||||
f->upvalues[i].ro = LoadByte(S);
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
@ -177,14 +177,24 @@ do -- constants
|
||||
local <const> a, b, <const> c = 10, 20, 30
|
||||
b = a + c + b -- 'b' is not constant
|
||||
assert(a == 10 and b == 60 and c == 30)
|
||||
local function checkro (code, name)
|
||||
local function checkro (name, code)
|
||||
local st, msg = load(code)
|
||||
local gab = string.format("attempt to assign to const variable '%s'", name)
|
||||
assert(not st and string.find(msg, gab))
|
||||
end
|
||||
checkro("local x, <const> y, z = 10, 20, 30; x = 11; y = 12", "y")
|
||||
checkro("local <const> x, y, <const> z = 10, 20, 30; x = 11", "x")
|
||||
checkro("local <const> x, y, <const> z = 10, 20, 30; y = 10; z = 11", "z")
|
||||
checkro("y", "local x, <const> y, z = 10, 20, 30; x = 11; y = 12")
|
||||
checkro("x", "local <const> x, y, <const> z = 10, 20, 30; x = 11")
|
||||
checkro("z", "local <const> x, y, <const> z = 10, 20, 30; y = 10; z = 11")
|
||||
|
||||
checkro("z", [[
|
||||
local a, <const> z, b = 10;
|
||||
function foo() a = 20; z = 32; end
|
||||
]])
|
||||
|
||||
checkro("var1", [[
|
||||
local a, <const> var1 = 10;
|
||||
function foo() a = 20; z = function () var1 = 12; end end
|
||||
]])
|
||||
end
|
||||
|
||||
|
||||
|
||||
Loading…
Reference in New Issue
Block a user