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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.compiler;
import java.util.Hashtable;
import org.luaj.vm2.LocVars;
import org.luaj.vm2.Lua;
import org.luaj.vm2.LuaDouble;
import org.luaj.vm2.LuaInteger;
import org.luaj.vm2.LuaString;
import org.luaj.vm2.LuaTable;
import org.luaj.vm2.LuaUserdata;
import org.luaj.vm2.LuaValue;
import org.luaj.vm2.Prototype;
import org.luaj.vm2.Upvaldesc;
import org.luaj.vm2.compiler.LexState.ConsControl;
import org.luaj.vm2.compiler.LexState.expdesc;
public class FuncState extends LuaC {
static class BlockCnt {
BlockCnt previous; /* chain */
short firstlabel; /* index of first label in this block */
short firstgoto; /* index of first pending goto in this block */
short nactvar; /* # active locals outside the breakable structure */
boolean upval; /* true if some variable in the block is an upvalue */
boolean isloop; /* true if `block' is a loop */
};
Prototype f; /* current function header */
Hashtable h; /* table to find (and reuse) elements in `k' */
FuncState prev; /* enclosing function */
LexState ls; /* lexical state */
LuaC L; /* compiler being invoked */
BlockCnt bl; /* chain of current blocks */
int pc; /* next position to code (equivalent to `ncode') */
int lasttarget; /* `pc' of last `jump target' */
IntPtr jpc; /* list of pending jumps to `pc' */
int nk; /* number of elements in `k' */
int np; /* number of elements in `p' */
int firstlocal; /* index of first local var (in Dyndata array) */
short nlocvars; /* number of elements in `locvars' */
short nactvar; /* number of active local variables */
short nups; /* number of upvalues */
short freereg; /* first free register */
FuncState() {
}
// =============================================================
// from lcode.h
// =============================================================
InstructionPtr getcodePtr(expdesc e) {
return new InstructionPtr( f.code, e.u.info );
}
int getcode(expdesc e) {
return f.code[e.u.info];
}
int codeAsBx(int o, int A, int sBx) {
return codeABx(o,A,sBx+MAXARG_sBx);
}
void setmultret(expdesc e) {
setreturns(e, LUA_MULTRET);
}
// =============================================================
// from lparser.c
// =============================================================
/* check for repeated labels on the same block */
void checkrepeated (LexState.Labeldesc[] ll, int ll_n, LuaString label) {
int i;
for (i = bl.firstlabel; i < ll_n; i++) {
if (label.eq_b(ll[i].name)) {
String msg = ls.L.pushfstring(
"label '" + label + " already defined on line " + ll[i].line);
ls.semerror(msg);
}
}
}
void checklimit(int v, int l, String msg) {
if ( v > l )
errorlimit( l, msg );
}
void errorlimit (int limit, String what) {
// TODO: report message logic.
String msg = (f.linedefined == 0) ?
L.pushfstring("main function has more than "+limit+" "+what) :
L.pushfstring("function at line "+f.linedefined+" has more than "+limit+" "+what);
ls.lexerror(msg, 0);
}
LocVars getlocvar(int i) {
int idx = ls.dyd.actvar[firstlocal + i].idx;
_assert(idx < nlocvars);
return f.locvars[idx];
}
void removevars (int tolevel) {
ls.dyd.n_actvar -= (nactvar - tolevel);
while (nactvar > tolevel)
getlocvar(--nactvar).endpc = pc;
}
int searchupvalue (LuaString name) {
int i;
Upvaldesc[] up = f.upvalues;
for (i = 0; i < nups; i++)
if (up[i].name.eq_b(name))
return i;
return -1; /* not found */
}
int newupvalue (LuaString name, expdesc v) {
checklimit(nups + 1, LUAI_MAXUPVAL, "upvalues");
if (f.upvalues == null || nups + 1 > f.upvalues.length)
f.upvalues = realloc( f.upvalues, nups > 0 ? nups*2 : 1 );
f.upvalues[nups] = new Upvaldesc(name, v.k == LexState.VLOCAL, v.u.info);
return nups++;
}
int searchvar(LuaString n) {
int i;
for (i = nactvar - 1; i >= 0; i--) {
if (n.eq_b(getlocvar(i).varname))
return i;
}
return -1; /* not found */
}
void markupval(int level) {
BlockCnt bl = this.bl;
while (bl.nactvar > level)
bl = bl.previous;
bl.upval = true;
}
static int singlevaraux(FuncState fs, LuaString n, expdesc var, int base) {
if (fs == null) /* no more levels? */
return LexState.VVOID; /* default is global */
int v = fs.searchvar(n); /* look up at current level */
if (v >= 0) {
var.init(LexState.VLOCAL, v);
if (base == 0)
fs.markupval(v); /* local will be used as an upval */
return LexState.VLOCAL;
} else { /* not found at current level; try upvalues */
int idx = fs.searchupvalue(n); /* try existing upvalues */
if (idx < 0) { /* not found? */
if (singlevaraux(fs.prev, n, var, 0) == LexState.VVOID) /* try upper levels */
return LexState.VVOID; /* not found; is a global */
/* else was LOCAL or UPVAL */
idx = fs.newupvalue(n, var); /* will be a new upvalue */
}
var.init(LexState.VUPVAL, idx);
return LexState.VUPVAL;
}
}
/*
** "export" pending gotos to outer level, to check them against
** outer labels; if the block being exited has upvalues, and
** the goto exits the scope of any variable (which can be the
** upvalue), close those variables being exited.
*/
void movegotosout(BlockCnt bl) {
int i = bl.firstgoto;
final LexState.Labeldesc[] gl = ls.dyd.gt;
/* correct pending gotos to current block and try to close it
with visible labels */
while (i < ls.dyd.n_gt) {
LexState.Labeldesc gt = gl[i];
if (gt.nactvar > bl.nactvar) {
if (bl.upval)
patchclose(gt.pc, bl.nactvar);
gt.nactvar = bl.nactvar;
}
if (!ls.findlabel(i))
i++; /* move to next one */
}
}
void enterblock (BlockCnt bl, boolean isloop) {
bl.isloop = isloop;
bl.nactvar = nactvar;
bl.firstlabel = (short) ls.dyd.n_label;
bl.firstgoto = (short) ls.dyd.n_gt;
bl.upval = false;
bl.previous = this.bl;
this.bl = bl;
_assert(this.freereg == this.nactvar);
}
void leaveblock() {
BlockCnt bl = this.bl;
if (bl.previous != null && bl.upval) {
/* create a 'jump to here' to close upvalues */
int j = this.jump();
this.patchclose(j, bl.nactvar);
this.patchtohere(j);
}
if (bl.isloop)
ls.breaklabel(); /* close pending breaks */
this.bl = bl.previous;
this.removevars(bl.nactvar);
_assert(bl.nactvar == this.nactvar);
this.freereg = this.nactvar; /* free registers */
ls.dyd.n_label = bl.firstlabel; /* remove local labels */
if (bl.previous != null) /* inner block? */
this.movegotosout(bl); /* update pending gotos to outer block */
else if (bl.firstgoto < ls.dyd.n_gt) /* pending gotos in outer block? */
ls.undefgoto(ls.dyd.gt[bl.firstgoto]); /* error */
}
void closelistfield(ConsControl cc) {
if (cc.v.k == LexState.VVOID)
return; /* there is no list item */
this.exp2nextreg(cc.v);
cc.v.k = LexState.VVOID;
if (cc.tostore == LFIELDS_PER_FLUSH) {
this.setlist(cc.t.u.info, cc.na, cc.tostore); /* flush */
cc.tostore = 0; /* no more items pending */
}
}
boolean hasmultret(int k) {
return ((k) == LexState.VCALL || (k) == LexState.VVARARG);
}
void lastlistfield (ConsControl cc) {
if (cc.tostore == 0) return;
if (hasmultret(cc.v.k)) {
this.setmultret(cc.v);
this.setlist(cc.t.u.info, cc.na, LUA_MULTRET);
cc.na--; /** do not count last expression (unknown number of elements) */
}
else {
if (cc.v.k != LexState.VVOID)
this.exp2nextreg(cc.v);
this.setlist(cc.t.u.info, cc.na, cc.tostore);
}
}
// =============================================================
// from lcode.c
// =============================================================
void nil(int from, int n) {
int l = from + n - 1; /* last register to set nil */
if (this.pc > this.lasttarget && pc > 0) { /* no jumps to current position? */
final int previous_code = f.code[pc - 1];
if (GET_OPCODE(previous_code) == OP_LOADNIL) {
int pfrom = GETARG_A(previous_code);
int pl = pfrom + GETARG_B(previous_code);
if ((pfrom <= from && from <= pl + 1)
|| (from <= pfrom && pfrom <= l + 1)) { /* can connect both? */
if (pfrom < from)
from = pfrom; /* from = min(from, pfrom) */
if (pl > l)
l = pl; /* l = max(l, pl) */
InstructionPtr previous = new InstructionPtr(this.f.code, this.pc - 1);
SETARG_A(previous, from);
SETARG_B(previous, l - from);
return;
}
} /* else go through */
}
this.codeABC(OP_LOADNIL, from, n - 1, 0);
}
int jump() {
int jpc = this.jpc.i; /* save list of jumps to here */
this.jpc.i = LexState.NO_JUMP;
IntPtr j = new IntPtr(this.codeAsBx(OP_JMP, 0, LexState.NO_JUMP));
this.concat(j, jpc); /* keep them on hold */
return j.i;
}
void ret(int first, int nret) {
this.codeABC(OP_RETURN, first, nret + 1, 0);
}
int condjump(int /* OpCode */op, int A, int B, int C) {
this.codeABC(op, A, B, C);
return this.jump();
}
void fixjump(int pc, int dest) {
InstructionPtr jmp = new InstructionPtr(this.f.code, pc);
int offset = dest - (pc + 1);
_assert (dest != LexState.NO_JUMP);
if (Math.abs(offset) > MAXARG_sBx)
ls.syntaxerror("control structure too long");
SETARG_sBx(jmp, offset);
}
/*
* * returns current `pc' and marks it as a jump target (to avoid wrong *
* optimizations with consecutive instructions not in the same basic block).
*/
int getlabel() {
this.lasttarget = this.pc;
return this.pc;
}
int getjump(int pc) {
int offset = GETARG_sBx(this.f.code[pc]);
/* point to itself represents end of list */
if (offset == LexState.NO_JUMP)
/* end of list */
return LexState.NO_JUMP;
else
/* turn offset into absolute position */
return (pc + 1) + offset;
}
InstructionPtr getjumpcontrol(int pc) {
InstructionPtr pi = new InstructionPtr(this.f.code, pc);
if (pc >= 1 && testTMode(GET_OPCODE(pi.code[pi.idx - 1])))
return new InstructionPtr(pi.code, pi.idx - 1);
else
return pi;
}
/*
* * check whether list has any jump that do not produce a value * (or
* produce an inverted value)
*/
boolean need_value(int list) {
for (; list != LexState.NO_JUMP; list = this.getjump(list)) {
int i = this.getjumpcontrol(list).get();
if (GET_OPCODE(i) != OP_TESTSET)
return true;
}
return false; /* not found */
}
boolean patchtestreg(int node, int reg) {
InstructionPtr i = this.getjumpcontrol(node);
if (GET_OPCODE(i.get()) != OP_TESTSET)
/* cannot patch other instructions */
return false;
if (reg != NO_REG && reg != GETARG_B(i.get()))
SETARG_A(i, reg);
else
/* no register to put value or register already has the value */
i.set(CREATE_ABC(OP_TEST, GETARG_B(i.get()), 0, Lua.GETARG_C(i.get())));
return true;
}
void removevalues(int list) {
for (; list != LexState.NO_JUMP; list = this.getjump(list))
this.patchtestreg(list, NO_REG);
}
void patchlistaux(int list, int vtarget, int reg, int dtarget) {
while (list != LexState.NO_JUMP) {
int next = this.getjump(list);
if (this.patchtestreg(list, reg))
this.fixjump(list, vtarget);
else
this.fixjump(list, dtarget); /* jump to default target */
list = next;
}
}
void dischargejpc() {
this.patchlistaux(this.jpc.i, this.pc, NO_REG, this.pc);
this.jpc.i = LexState.NO_JUMP;
}
void patchlist(int list, int target) {
if (target == this.pc)
this.patchtohere(list);
else {
_assert (target < this.pc);
this.patchlistaux(list, target, NO_REG, target);
}
}
void patchclose(int list, int level) {
level++; /* argument is +1 to reserve 0 as non-op */
while (list != LexState.NO_JUMP) {
int next = getjump(list);
_assert(GET_OPCODE(f.code[list]) == OP_JMP
&& (GETARG_A(f.code[list]) == 0 || GETARG_A(f.code[list]) >= level));
SETARG_A(f.code, list, level);
list = next;
}
}
void patchtohere(int list) {
this.getlabel();
this.concat(this.jpc, list);
}
void concat(IntPtr l1, int l2) {
if (l2 == LexState.NO_JUMP)
return;
if (l1.i == LexState.NO_JUMP)
l1.i = l2;
else {
int list = l1.i;
int next;
while ((next = this.getjump(list)) != LexState.NO_JUMP)
/* find last element */
list = next;
this.fixjump(list, l2);
}
}
void checkstack(int n) {
int newstack = this.freereg + n;
if (newstack > this.f.maxstacksize) {
if (newstack >= MAXSTACK)
ls.syntaxerror("function or expression too complex");
this.f.maxstacksize = newstack;
}
}
void reserveregs(int n) {
this.checkstack(n);
this.freereg += n;
}
void freereg(int reg) {
if (!ISK(reg) && reg >= this.nactvar) {
this.freereg--;
_assert (reg == this.freereg);
}
}
void freeexp(expdesc e) {
if (e.k == LexState.VNONRELOC)
this.freereg(e.u.info);
}
int addk(LuaValue v) {
if (this.h == null) {
this.h = new Hashtable();
} else if (this.h.containsKey(v)) {
return ((Integer) h.get(v)).intValue();
}
final int idx = this.nk;
this.h.put(v, new Integer(idx));
final Prototype f = this.f;
if (f.k == null || nk + 1 >= f.k.length)
f.k = realloc( f.k, nk*2 + 1 );
f.k[this.nk++] = v;
return idx;
}
int stringK(LuaString s) {
return this.addk(s);
}
int numberK(LuaValue r) {
if ( r instanceof LuaDouble ) {
double d = r.todouble();
int i = (int) d;
if ( d == (double) i )
r = LuaInteger.valueOf(i);
}
return this.addk(r);
}
int boolK(boolean b) {
return this.addk((b ? LuaValue.TRUE : LuaValue.FALSE));
}
int nilK() {
return this.addk(LuaValue.NIL);
}
void setreturns(expdesc e, int nresults) {
if (e.k == LexState.VCALL) { /* expression is an open function call? */
SETARG_C(this.getcodePtr(e), nresults + 1);
} else if (e.k == LexState.VVARARG) {
SETARG_B(this.getcodePtr(e), nresults + 1);
SETARG_A(this.getcodePtr(e), this.freereg);
this.reserveregs(1);
}
}
void setoneret(expdesc e) {
if (e.k == LexState.VCALL) { /* expression is an open function call? */
e.k = LexState.VNONRELOC;
e.u.info = GETARG_A(this.getcode(e));
} else if (e.k == LexState.VVARARG) {
SETARG_B(this.getcodePtr(e), 2);
e.k = LexState.VRELOCABLE; /* can relocate its simple result */
}
}
void dischargevars(expdesc e) {
switch (e.k) {
case LexState.VLOCAL: {
e.k = LexState.VNONRELOC;
break;
}
case LexState.VUPVAL: {
e.u.info = this.codeABC(OP_GETUPVAL, 0, e.u.info, 0);
e.k = LexState.VRELOCABLE;
break;
}
case LexState.VINDEXED: {
int op = OP_GETTABUP; /* assume 't' is in an upvalue */
this.freereg(e.u.ind_idx);
if (e.u.ind_vt == LexState.VLOCAL) { /* 't' is in a register? */
this.freereg(e.u.ind_t);
op = OP_GETTABLE;
}
e.u.info = this.codeABC(op, 0, e.u.ind_t, e.u.ind_idx);
e.k = LexState.VRELOCABLE;
break;
}
case LexState.VVARARG:
case LexState.VCALL: {
this.setoneret(e);
break;
}
default:
break; /* there is one value available (somewhere) */
}
}
int code_label(int A, int b, int jump) {
this.getlabel(); /* those instructions may be jump targets */
return this.codeABC(OP_LOADBOOL, A, b, jump);
}
void discharge2reg(expdesc e, int reg) {
this.dischargevars(e);
switch (e.k) {
case LexState.VNIL: {
this.nil(reg, 1);
break;
}
case LexState.VFALSE:
case LexState.VTRUE: {
this.codeABC(OP_LOADBOOL, reg, (e.k == LexState.VTRUE ? 1 : 0),
0);
break;
}
case LexState.VK: {
this.codeABx(OP_LOADK, reg, e.u.info);
break;
}
case LexState.VKNUM: {
this.codeABx(OP_LOADK, reg, this.numberK(e.u.nval()));
break;
}
case LexState.VRELOCABLE: {
InstructionPtr pc = this.getcodePtr(e);
SETARG_A(pc, reg);
break;
}
case LexState.VNONRELOC: {
if (reg != e.u.info)
this.codeABC(OP_MOVE, reg, e.u.info, 0);
break;
}
default: {
_assert (e.k == LexState.VVOID || e.k == LexState.VJMP);
return; /* nothing to do... */
}
}
e.u.info = reg;
e.k = LexState.VNONRELOC;
}
void discharge2anyreg(expdesc e) {
if (e.k != LexState.VNONRELOC) {
this.reserveregs(1);
this.discharge2reg(e, this.freereg - 1);
}
}
void exp2reg(expdesc e, int reg) {
this.discharge2reg(e, reg);
if (e.k == LexState.VJMP)
this.concat(e.t, e.u.info); /* put this jump in `t' list */
if (e.hasjumps()) {
int _final; /* position after whole expression */
int p_f = LexState.NO_JUMP; /* position of an eventual LOAD false */
int p_t = LexState.NO_JUMP; /* position of an eventual LOAD true */
if (this.need_value(e.t.i) || this.need_value(e.f.i)) {
int fj = (e.k == LexState.VJMP) ? LexState.NO_JUMP : this
.jump();
p_f = this.code_label(reg, 0, 1);
p_t = this.code_label(reg, 1, 0);
this.patchtohere(fj);
}
_final = this.getlabel();
this.patchlistaux(e.f.i, _final, reg, p_f);
this.patchlistaux(e.t.i, _final, reg, p_t);
}
e.f.i = e.t.i = LexState.NO_JUMP;
e.u.info = reg;
e.k = LexState.VNONRELOC;
}
void exp2nextreg(expdesc e) {
this.dischargevars(e);
this.freeexp(e);
this.reserveregs(1);
this.exp2reg(e, this.freereg - 1);
}
int exp2anyreg(expdesc e) {
this.dischargevars(e);
if (e.k == LexState.VNONRELOC) {
if (!e.hasjumps())
return e.u.info; /* exp is already in a register */
if (e.u.info >= this.nactvar) { /* reg. is not a local? */
this.exp2reg(e, e.u.info); /* put value on it */
return e.u.info;
}
}
this.exp2nextreg(e); /* default */
return e.u.info;
}
void exp2anyregup (expdesc e) {
if (e.k != LexState.VUPVAL || e.hasjumps())
exp2anyreg(e);
}
void exp2val(expdesc e) {
if (e.hasjumps())
this.exp2anyreg(e);
else
this.dischargevars(e);
}
int exp2RK(expdesc e) {
this.exp2val(e);
switch (e.k) {
case LexState.VTRUE:
case LexState.VFALSE:
case LexState.VNIL: {
if (this.nk <= MAXINDEXRK) { /* constant fit in RK operand? */
e.u.info = (e.k == LexState.VNIL) ? this.nilK()
: this.boolK((e.k == LexState.VTRUE));
e.k = LexState.VK;
return RKASK(e.u.info);
} else
break;
}
case LexState.VKNUM: {
e.u.info = this.numberK(e.u.nval());
e.k = LexState.VK;
/* go through */
}
case LexState.VK: {
if (e.u.info <= MAXINDEXRK) /* constant fit in argC? */
return RKASK(e.u.info);
else
break;
}
default:
break;
}
/* not a constant in the right range: put it in a register */
return this.exp2anyreg(e);
}
void storevar(expdesc var, expdesc ex) {
switch (var.k) {
case LexState.VLOCAL: {
this.freeexp(ex);
this.exp2reg(ex, var.u.info);
return;
}
case LexState.VUPVAL: {
int e = this.exp2anyreg(ex);
this.codeABC(OP_SETUPVAL, e, var.u.info, 0);
break;
}
case LexState.VINDEXED: {
int op = (var.u.ind_vt == LexState.VLOCAL) ? OP_SETTABLE : OP_SETTABUP;
int e = this.exp2RK(ex);
this.codeABC(op, var.u.ind_t, var.u.ind_idx, e);
break;
}
default: {
_assert (false); /* invalid var kind to store */
break;
}
}
this.freeexp(ex);
}
void self(expdesc e, expdesc key) {
int func;
this.exp2anyreg(e);
this.freeexp(e);
func = this.freereg;
this.reserveregs(2);
this.codeABC(OP_SELF, func, e.u.info, this.exp2RK(key));
this.freeexp(key);
e.u.info = func;
e.k = LexState.VNONRELOC;
}
void invertjump(expdesc e) {
InstructionPtr pc = this.getjumpcontrol(e.u.info);
_assert (testTMode(GET_OPCODE(pc.get()))
&& GET_OPCODE(pc.get()) != OP_TESTSET && Lua
.GET_OPCODE(pc.get()) != OP_TEST);
// SETARG_A(pc, !(GETARG_A(pc.get())));
int a = GETARG_A(pc.get());
int nota = (a!=0? 0: 1);
SETARG_A(pc, nota);
}
int jumponcond(expdesc e, int cond) {
if (e.k == LexState.VRELOCABLE) {
int ie = this.getcode(e);
if (GET_OPCODE(ie) == OP_NOT) {
this.pc--; /* remove previous OP_NOT */
return this.condjump(OP_TEST, GETARG_B(ie), 0, (cond!=0? 0: 1));
}
/* else go through */
}
this.discharge2anyreg(e);
this.freeexp(e);
return this.condjump(OP_TESTSET, NO_REG, e.u.info, cond);
}
void goiftrue(expdesc e) {
int pc; /* pc of last jump */
this.dischargevars(e);
switch (e.k) {
case LexState.VJMP: {
this.invertjump(e);
pc = e.u.info;
break;
}
case LexState.VK:
case LexState.VKNUM:
case LexState.VTRUE: {
pc = LexState.NO_JUMP; /* always true; do nothing */
break;
}
default: {
pc = this.jumponcond(e, 0);
break;
}
}
this.concat(e.f, pc); /* insert last jump in `f' list */
this.patchtohere(e.t.i);
e.t.i = LexState.NO_JUMP;
}
void goiffalse(expdesc e) {
int pc; /* pc of last jump */
this.dischargevars(e);
switch (e.k) {
case LexState.VJMP: {
pc = e.u.info;
break;
}
case LexState.VNIL:
case LexState.VFALSE: {
pc = LexState.NO_JUMP; /* always false; do nothing */
break;
}
default: {
pc = this.jumponcond(e, 1);
break;
}
}
this.concat(e.t, pc); /* insert last jump in `t' list */
this.patchtohere(e.f.i);
e.f.i = LexState.NO_JUMP;
}
void codenot(expdesc e) {
this.dischargevars(e);
switch (e.k) {
case LexState.VNIL:
case LexState.VFALSE: {
e.k = LexState.VTRUE;
break;
}
case LexState.VK:
case LexState.VKNUM:
case LexState.VTRUE: {
e.k = LexState.VFALSE;
break;
}
case LexState.VJMP: {
this.invertjump(e);
break;
}
case LexState.VRELOCABLE:
case LexState.VNONRELOC: {
this.discharge2anyreg(e);
this.freeexp(e);
e.u.info = this.codeABC(OP_NOT, 0, e.u.info, 0);
e.k = LexState.VRELOCABLE;
break;
}
default: {
_assert (false); /* cannot happen */
break;
}
}
/* interchange true and false lists */
{
int temp = e.f.i;
e.f.i = e.t.i;
e.t.i = temp;
}
this.removevalues(e.f.i);
this.removevalues(e.t.i);
}
static boolean vkisinreg(int k) {
return ((k) == LexState.VNONRELOC || (k) == LexState.VLOCAL);
}
void indexed(expdesc t, expdesc k) {
t.u.ind_t = (short) t.u.info;
t.u.ind_idx = (short) this.exp2RK(k);
LuaC._assert(t.k == LexState.VUPVAL || vkisinreg(t.k));
t.u.ind_vt = (short) ((t.k == LexState.VUPVAL) ? LexState.VUPVAL : LexState.VLOCAL);
t.k = LexState.VINDEXED;
}
boolean constfolding(int op, expdesc e1, expdesc e2) {
LuaValue v1, v2, r;
if (!e1.isnumeral() || !e2.isnumeral())
return false;
if ((op == OP_DIV || op == OP_MOD) && e2.u.nval().eq_b(LuaValue.ZERO))
return false; /* do not attempt to divide by 0 */
v1 = e1.u.nval();
v2 = e2.u.nval();
switch (op) {
case OP_ADD:
r = v1.add(v2);
break;
case OP_SUB:
r = v1.sub(v2);
break;
case OP_MUL:
r = v1.mul(v2);
break;
case OP_DIV:
r = v1.div(v2);
break;
case OP_MOD:
r = v1.mod(v2);
break;
case OP_POW:
r = v1.pow(v2);
break;
case OP_UNM:
r = v1.neg();
break;
case OP_LEN:
// r = v1.len();
// break;
return false; /* no constant folding for 'len' */
default:
_assert (false);
r = null;
break;
}
if ( Double.isNaN(r.todouble()) )
return false; /* do not attempt to produce NaN */
e1.u.setNval( r );
return true;
}
void codearith(int op, expdesc e1, expdesc e2, int line) {
if (constfolding(op, e1, e2))
return;
else {
int o2 = (op != OP_UNM && op != OP_LEN) ? this.exp2RK(e2)
: 0;
int o1 = this.exp2RK(e1);
if (o1 > o2) {
this.freeexp(e1);
this.freeexp(e2);
} else {
this.freeexp(e2);
this.freeexp(e1);
}
e1.u.info = this.codeABC(op, 0, o1, o2);
e1.k = LexState.VRELOCABLE;
fixline(line);
}
}
void codecomp(int /* OpCode */op, int cond, expdesc e1, expdesc e2) {
int o1 = this.exp2RK(e1);
int o2 = this.exp2RK(e2);
this.freeexp(e2);
this.freeexp(e1);
if (cond == 0 && op != OP_EQ) {
int temp; /* exchange args to replace by `<' or `<=' */
temp = o1;
o1 = o2;
o2 = temp; /* o1 <==> o2 */
cond = 1;
}
e1.u.info = this.condjump(op, cond, o1, o2);
e1.k = LexState.VJMP;
}
void prefix(int /* UnOpr */op, expdesc e, int line) {
expdesc e2 = new expdesc();
e2.init(LexState.VKNUM, 0);
switch (op) {
case LexState.OPR_MINUS: {
if (e.isnumeral()) /* minus constant? */
e.u.setNval(e.u.nval().neg()); /* fold it */
else {
this.exp2anyreg(e);
this.codearith(OP_UNM, e, e2, line);
}
break;
}
case LexState.OPR_NOT:
this.codenot(e);
break;
case LexState.OPR_LEN: {
this.exp2anyreg(e); /* cannot operate on constants */
this.codearith(OP_LEN, e, e2, line);
break;
}
default:
_assert (false);
}
}
void infix(int /* BinOpr */op, expdesc v) {
switch (op) {
case LexState.OPR_AND: {
this.goiftrue(v);
break;
}
case LexState.OPR_OR: {
this.goiffalse(v);
break;
}
case LexState.OPR_CONCAT: {
this.exp2nextreg(v); /* operand must be on the `stack' */
break;
}
case LexState.OPR_ADD:
case LexState.OPR_SUB:
case LexState.OPR_MUL:
case LexState.OPR_DIV:
case LexState.OPR_MOD:
case LexState.OPR_POW: {
if (!v.isnumeral())
this.exp2RK(v);
break;
}
default: {
this.exp2RK(v);
break;
}
}
}
void posfix(int op, expdesc e1, expdesc e2, int line) {
switch (op) {
case LexState.OPR_AND: {
_assert (e1.t.i == LexState.NO_JUMP); /* list must be closed */
this.dischargevars(e2);
this.concat(e2.f, e1.f.i);
// *e1 = *e2;
e1.setvalue(e2);
break;
}
case LexState.OPR_OR: {
_assert (e1.f.i == LexState.NO_JUMP); /* list must be closed */
this.dischargevars(e2);
this.concat(e2.t, e1.t.i);
// *e1 = *e2;
e1.setvalue(e2);
break;
}
case LexState.OPR_CONCAT: {
this.exp2val(e2);
if (e2.k == LexState.VRELOCABLE
&& GET_OPCODE(this.getcode(e2)) == OP_CONCAT) {
_assert (e1.u.info == GETARG_B(this.getcode(e2)) - 1);
this.freeexp(e1);
SETARG_B(this.getcodePtr(e2), e1.u.info);
e1.k = LexState.VRELOCABLE;
e1.u.info = e2.u.info;
} else {
this.exp2nextreg(e2); /* operand must be on the 'stack' */
this.codearith(OP_CONCAT, e1, e2, line);
}
break;
}
case LexState.OPR_ADD:
this.codearith(OP_ADD, e1, e2, line);
break;
case LexState.OPR_SUB:
this.codearith(OP_SUB, e1, e2, line);
break;
case LexState.OPR_MUL:
this.codearith(OP_MUL, e1, e2, line);
break;
case LexState.OPR_DIV:
this.codearith(OP_DIV, e1, e2, line);
break;
case LexState.OPR_MOD:
this.codearith(OP_MOD, e1, e2, line);
break;
case LexState.OPR_POW:
this.codearith(OP_POW, e1, e2, line);
break;
case LexState.OPR_EQ:
this.codecomp(OP_EQ, 1, e1, e2);
break;
case LexState.OPR_NE:
this.codecomp(OP_EQ, 0, e1, e2);
break;
case LexState.OPR_LT:
this.codecomp(OP_LT, 1, e1, e2);
break;
case LexState.OPR_LE:
this.codecomp(OP_LE, 1, e1, e2);
break;
case LexState.OPR_GT:
this.codecomp(OP_LT, 0, e1, e2);
break;
case LexState.OPR_GE:
this.codecomp(OP_LE, 0, e1, e2);
break;
default:
_assert (false);
}
}
void fixline(int line) {
this.f.lineinfo[this.pc - 1] = line;
}
int code(int instruction, int line) {
Prototype f = this.f;
this.dischargejpc(); /* `pc' will change */
/* put new instruction in code array */
if (f.code == null || this.pc + 1 > f.code.length)
f.code = LuaC.realloc(f.code, this.pc * 2 + 1);
f.code[this.pc] = instruction;
/* save corresponding line information */
if (f.lineinfo == null || this.pc + 1 > f.lineinfo.length)
f.lineinfo = LuaC.realloc(f.lineinfo,
this.pc * 2 + 1);
f.lineinfo[this.pc] = line;
return this.pc++;
}
int codeABC(int o, int a, int b, int c) {
_assert (getOpMode(o) == iABC);
_assert (getBMode(o) != OpArgN || b == 0);
_assert (getCMode(o) != OpArgN || c == 0);
return this.code(CREATE_ABC(o, a, b, c), this.ls.lastline);
}
int codeABx(int o, int a, int bc) {
_assert (getOpMode(o) == iABx || getOpMode(o) == iAsBx);
_assert (getCMode(o) == OpArgN);
_assert (bc >= 0 && bc <= Lua.MAXARG_Bx);
return this.code(CREATE_ABx(o, a, bc), this.ls.lastline);
}
void setlist(int base, int nelems, int tostore) {
int c = (nelems - 1) / LFIELDS_PER_FLUSH + 1;
int b = (tostore == LUA_MULTRET) ? 0 : tostore;
_assert (tostore != 0);
if (c <= MAXARG_C)
this.codeABC(OP_SETLIST, base, b, c);
else {
this.codeABC(OP_SETLIST, base, b, 0);
this.code(c, this.ls.lastline);
}
this.freereg = (short) (base + 1); /* free registers with list values */
}
}