示例#1
0
/* Narrowing of power operator or math.pow. */
TRef lj_opt_narrow_pow(jit_State *J, TRef rb, TRef rc, TValue *vc)
{
  lua_Number n;
  if (tvisstr(vc) && !lj_str_tonum(strV(vc), vc))
    lj_trace_err(J, LJ_TRERR_BADTYPE);
  n = numV(vc);
  /* Limit narrowing for pow to small exponents (or for two constants). */
  if ((tref_isk(rc) && tref_isint(rc) && tref_isk(rb)) ||
      ((J->flags & JIT_F_OPT_NARROW) &&
       (numisint(n) && n >= -65536.0 && n <= 65536.0))) {
    TRef tmp;
    if (!tref_isinteger(rc)) {
      if (tref_isstr(rc))
	rc = emitir(IRTG(IR_STRTO, IRT_NUM), rc, 0);
      rc = emitir(IRTGI(IR_TOINT), rc, IRTOINT_CHECK); /* Guarded TOINT! */
    }
    if (!tref_isk(rc)) {  /* Range guard: -65536 <= i <= 65536 */
      tmp = emitir(IRTI(IR_ADD), rc, lj_ir_kint(J, 65536-2147483647-1));
      emitir(IRTGI(IR_LE), tmp, lj_ir_kint(J, 2*65536-2147483647-1));
    }
    return emitir(IRTN(IR_POWI), rb, rc);
  }
  /* FOLD covers most cases, but some are easier to do here. */
  if (tref_isk(rb) && tvispone(ir_knum(IR(tref_ref(rb)))))
    return rb;  /* 1 ^ x ==> 1 */
  rc = lj_ir_tonum(J, rc);
  if (tref_isk(rc) && ir_knum(IR(tref_ref(rc)))->n == 0.5)
    return emitir(IRTN(IR_FPMATH), rb, IRFPM_SQRT);  /* x ^ 0.5 ==> sqrt(x) */
  /* Split up b^c into exp2(c*log2(b)). Assembler may rejoin later. */
  rb = emitir(IRTN(IR_FPMATH), rb, IRFPM_LOG2);
  rc = emitir(IRTN(IR_MUL), rb, rc);
  return emitir(IRTN(IR_FPMATH), rc, IRFPM_EXP2);
}
static void LJ_FASTCALL recff_math_minmax(jit_State *J, RecordFFData *rd)
{
  TRef tr = lj_ir_tonumber(J, J->base[0]);
  uint32_t op = rd->data;
  BCReg i;
  for (i = 1; J->base[i] != 0; i++) {
    TRef tr2 = lj_ir_tonumber(J, J->base[i]);
    IRType t = IRT_INT;
    if (!(tref_isinteger(tr) && tref_isinteger(tr2))) {
      if (tref_isinteger(tr)) tr = emitir(IRTN(IR_CONV), tr, IRCONV_NUM_INT);
      if (tref_isinteger(tr2)) tr2 = emitir(IRTN(IR_CONV), tr2, IRCONV_NUM_INT);
      t = IRT_NUM;
    }
    tr = emitir(IRT(op, t), tr, tr2);
  }
  J->base[0] = tr;
}
/* Record rounding functions math.floor and math.ceil. */
static void LJ_FASTCALL recff_math_round(jit_State *J, RecordFFData *rd)
{
  TRef tr = J->base[0];
  if (!tref_isinteger(tr)) {  /* Pass through integers unmodified. */
    tr = emitir(IRTN(IR_FPMATH), lj_ir_tonum(J, tr), rd->data);
    /* Result is integral (or NaN/Inf), but may not fit an int32_t. */
    if (LJ_DUALNUM) {  /* Try to narrow using a guarded conversion to int. */
      lua_Number n = lj_vm_foldfpm(numberVnum(&rd->argv[0]), rd->data);
      if (n == (lua_Number)lj_num2int(n))
	tr = emitir(IRTGI(IR_CONV), tr, IRCONV_INT_NUM|IRCONV_CHECK);
    }
    J->base[0] = tr;
  }
}
static void LJ_FASTCALL recff_math_modf(jit_State *J, RecordFFData *rd)
{
  TRef tr = J->base[0];
  if (tref_isinteger(tr)) {
    J->base[0] = tr;
    J->base[1] = lj_ir_kint(J, 0);
  } else {
    TRef trt;
    tr = lj_ir_tonum(J, tr);
    trt = emitir(IRTN(IR_FPMATH), tr, IRFPM_TRUNC);
    J->base[0] = trt;
    J->base[1] = emitir(IRTN(IR_SUB), tr, trt);
  }
  rd->nres = 2;
}
示例#5
0
/* Narrowing of modulo operator. */
TRef lj_opt_narrow_mod(jit_State *J, TRef rb, TRef rc)
{
  TRef tmp;
  if ((J->flags & JIT_F_OPT_NARROW) &&
      tref_isk(rc) && tref_isint(rc)) {  /* Optimize x % k. */
    int32_t k = IR(tref_ref(rc))->i;
    if (k > 0 && (k & (k-1)) == 0) {  /* i % 2^k ==> band(i, 2^k-1) */
      if (tref_isinteger(rb))
	return emitir(IRTI(IR_BAND), rb, lj_ir_kint(J, k-1));
    }
  }
  /* b % c ==> b - floor(b/c)*c */
  rb = lj_ir_tonum(J, rb);
  rc = lj_ir_tonum(J, rc);
  tmp = emitir(IRTN(IR_DIV), rb, rc);
  tmp = emitir(IRTN(IR_FPMATH), tmp, IRFPM_FLOOR);
  tmp = emitir(IRTN(IR_MUL), tmp, rc);
  return emitir(IRTN(IR_SUB), rb, tmp);
}