void codegen_dischargevars(FuncState *fs, expdesc *e)
{
switch (e->k) {
case VLOCAL: {
e->k = VNONRELOC;
break;
}
case VUPVAL: {
e->u.info = codegen_codeABC(fs, OP_GETUPVAL, 0, e->u.info, 0);
e->k = VRELOCABLE;
break;
}
case VINDEXED: {
OpCode op = OP_GETTABUP; /* assume 't' is in an upvalue */
freereg(fs, e->u.ind.idx);
if (e->u.ind.vt == VLOCAL) { /* 't' is in a register? */
freereg(fs, e->u.ind.t);
op = OP_GETTABLE;
}
e->u.info = codegen_codeABC(fs, op, 0, e->u.ind.t, e->u.ind.idx);
e->k = VRELOCABLE;
break;
}
case VVARARG:
case VCALL: {
codegen_setoneret(fs, e);
break;
}
default:
break; /* there is one value available (somewhere) */
}
}
void codegen_nil(FuncState *fs, int from, int n)
{
Instruction *previous;
int l = from + n - 1; /* last register to set nil */
if (fs->pc > fs->lasttarget) { /* no jumps to current position? */
previous = &fs->f->code[fs->pc-1];
if (GET_OPCODE(*previous) == OP_LOADNIL) {
int pfrom = GETARG_A(*previous);
int pl = pfrom + GETARG_B(*previous);
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) */
SETARG_A(*previous, from);
SETARG_B(*previous, l - from);
return;
}
} /* else go through */
}
codegen_codeABC(fs, OP_LOADNIL, from, n - 1, 0); /* else no optimization */
}
static void discharge2reg(ktap_funcstate *fs, ktap_expdesc *e, int reg)
{
codegen_dischargevars(fs, e);
switch (e->k) {
case VNIL: {
codegen_nil(fs, reg, 1);
break;
}
case VFALSE: case VTRUE: {
codegen_codeABC(fs, OP_LOADBOOL, reg, e->k == VTRUE, 0);
break;
}
case VEVENT:
codegen_codeABC(fs, OP_EVENT, reg, 0, 0);
break;
case VEVENTNAME:
codegen_codeABC(fs, OP_EVENTNAME, reg, 0, 0);
break;
case VEVENTARG:
codegen_codeABC(fs, OP_EVENTARG, reg, e->u.info, 0);
break;
case VK: {
codegen_codek(fs, reg, e->u.info);
break;
}
case VKNUM: {
codegen_codek(fs, reg, codegen_numberK(fs, e->u.nval));
break;
}
case VRELOCABLE: {
ktap_instruction *pc = &getcode(fs, e);
SETARG_A(*pc, reg);
break;
}
case VNONRELOC: {
if (reg != e->u.info)
codegen_codeABC(fs, OP_MOVE, reg, e->u.info, 0);
break;
}
default:
ktap_assert(e->k == VVOID || e->k == VJMP);
return; /* nothing to do... */
}
e->u.info = reg;
e->k = VNONRELOC;
}
static int condjump(FuncState *fs, OpCode op, int A, int B, int C)
{
codegen_codeABC(fs, op, A, B, C);
return codegen_jump(fs);
}
void codegen_ret(FuncState *fs, int first, int nret)
{
codegen_codeABC(fs, OP_RETURN, first, nret+1, 0);
}
static int code_label(FuncState *fs, int A, int b, int jump)
{
codegen_getlabel(fs); /* those instructions may be jump targets */
return codegen_codeABC(fs, OP_LOADBOOL, A, b, jump);
}
void codegen_ret(ktap_funcstate *fs, int first, int nret)
{
codegen_codeABC(fs, OP_RETURN, first, nret+1, 0);
}
