DUK_LOCAL duk_ret_t duk__math_minmax(duk_context *ctx, duk_double_t initial, duk__two_arg_func min_max) {
duk_idx_t n = duk_get_top(ctx);
duk_idx_t i;
duk_double_t res = initial;
duk_double_t t;
/*
* Note: fmax() does not match the E5 semantics. E5 requires
* that if -any- input to Math.max() is a NaN, the result is a
* NaN. fmax() will return a NaN only if -both- inputs are NaN.
* Same applies to fmin().
*
* Note: every input value must be coerced with ToNumber(), even
* if we know the result will be a NaN anyway: ToNumber() may have
* side effects for which even order of evaluation matters.
*/
for (i = 0; i < n; i++) {
t = duk_to_number(ctx, i);
if (DUK_FPCLASSIFY(t) == DUK_FP_NAN || DUK_FPCLASSIFY(res) == DUK_FP_NAN) {
/* Note: not normalized, but duk_push_number() will normalize */
res = (duk_double_t) DUK_DOUBLE_NAN;
} else {
res = (duk_double_t) min_max(res, (double) t);
}
}
duk_push_number(ctx, res);
return 1;
}
duk_int32_t duk_js_toint32(duk_hthread *thr, duk_tval *tv) {
duk_double_t d = duk_js_tonumber(thr, tv); /* invalidates tv */
d = duk__toint32_touint32_helper(d, 1);
DUK_ASSERT(DUK_FPCLASSIFY(d) == DUK_FP_ZERO || DUK_FPCLASSIFY(d) == DUK_FP_NORMAL);
DUK_ASSERT(d >= -2147483648.0 && d <= 2147483647.0); /* [-0x80000000,0x7fffffff] */
DUK_ASSERT(d == ((duk_double_t) ((duk_int32_t) d))); /* whole, won't clip */
return (duk_int32_t) d;
}
duk_uint32_t duk_js_touint32(duk_hthread *thr, duk_tval *tv) {
duk_double_t d = duk_js_tonumber(thr, tv); /* invalidates tv */
d = duk__toint32_touint32_helper(d, 0);
DUK_ASSERT(DUK_FPCLASSIFY(d) == DUK_FP_ZERO || DUK_FPCLASSIFY(d) == DUK_FP_NORMAL);
DUK_ASSERT(d >= 0.0 && d <= 4294967295.0); /* [0x00000000, 0xffffffff] */
DUK_ASSERT(d == ((duk_double_t) ((duk_uint32_t) d))); /* whole, won't clip */
return (duk_uint32_t) d;
}
duk_ret_t duk_bi_number_prototype_to_fixed(duk_context *ctx) {
duk_small_int_t frac_digits;
duk_double_t d;
duk_small_int_t c;
duk_small_uint_t n2s_flags;
frac_digits = (duk_small_int_t) duk_to_int_check_range(ctx, 0, 0, 20);
d = duk__push_this_number_plain(ctx);
c = (duk_small_int_t) DUK_FPCLASSIFY(d);
if (c == DUK_FP_NAN || c == DUK_FP_INFINITE) {
goto use_to_string;
}
if (d >= 1.0e21 || d <= -1.0e21) {
goto use_to_string;
}
n2s_flags = DUK_N2S_FLAG_FIXED_FORMAT |
DUK_N2S_FLAG_FRACTION_DIGITS;
duk_numconv_stringify(ctx,
10 /*radix*/,
frac_digits /*digits*/,
n2s_flags /*flags*/);
return 1;
use_to_string:
DUK_ASSERT_TOP(ctx, 2);
duk_to_string(ctx, -1);
return 1;
}
duk_ret_t duk_bi_number_prototype_to_exponential(duk_context *ctx) {
duk_bool_t frac_undefined;
duk_small_int_t frac_digits;
duk_double_t d;
duk_small_int_t c;
duk_small_uint_t n2s_flags;
d = duk__push_this_number_plain(ctx);
frac_undefined = duk_is_undefined(ctx, 0);
duk_to_int(ctx, 0); /* for side effects */
c = (duk_small_int_t) DUK_FPCLASSIFY(d);
if (c == DUK_FP_NAN || c == DUK_FP_INFINITE) {
goto use_to_string;
}
frac_digits = (duk_small_int_t) duk_to_int_check_range(ctx, 0, 0, 20);
n2s_flags = DUK_N2S_FLAG_FORCE_EXP |
(frac_undefined ? 0 : DUK_N2S_FLAG_FIXED_FORMAT);
duk_numconv_stringify(ctx,
10 /*radix*/,
frac_digits + 1 /*leading digit + fractions*/,
n2s_flags /*flags*/);
return 1;
use_to_string:
DUK_ASSERT_TOP(ctx, 2);
duk_to_string(ctx, -1);
return 1;
}
DUK_INTERNAL duk_int32_t duk_js_toint32(duk_hthread *thr, duk_tval *tv) {
duk_double_t d;
#if defined(DUK_USE_FASTINT)
if (DUK_TVAL_IS_FASTINT(tv)) {
return DUK_TVAL_GET_FASTINT_I32(tv);
}
#endif
d = duk_js_tonumber(thr, tv); /* invalidates tv */
d = duk__toint32_touint32_helper(d, 1);
DUK_ASSERT(DUK_FPCLASSIFY(d) == DUK_FP_ZERO || DUK_FPCLASSIFY(d) == DUK_FP_NORMAL);
DUK_ASSERT(d >= -2147483648.0 && d <= 2147483647.0); /* [-0x80000000,0x7fffffff] */
DUK_ASSERT(d == ((duk_double_t) ((duk_int32_t) d))); /* whole, won't clip */
return (duk_int32_t) d;
}
int duk_repl_isfinite(double x) {
int c = DUK_FPCLASSIFY(x);
if (c == DUK_FP_NAN || c == DUK_FP_INFINITE) {
return 0;
} else {
return 1;
}
}
DUK_INTERNAL duk_bool_t duk_js_toboolean(duk_tval *tv) {
switch (DUK_TVAL_GET_TAG(tv)) {
case DUK_TAG_UNDEFINED:
case DUK_TAG_NULL:
return 0;
case DUK_TAG_BOOLEAN:
return DUK_TVAL_GET_BOOLEAN(tv);
case DUK_TAG_STRING: {
duk_hstring *h = DUK_TVAL_GET_STRING(tv);
DUK_ASSERT(h != NULL);
return (DUK_HSTRING_GET_BYTELEN(h) > 0 ? 1 : 0);
}
case DUK_TAG_OBJECT: {
return 1;
}
case DUK_TAG_BUFFER: {
/* mimic semantics for strings */
duk_hbuffer *h = DUK_TVAL_GET_BUFFER(tv);
DUK_ASSERT(h != NULL);
return (DUK_HBUFFER_GET_SIZE(h) > 0 ? 1 : 0);
}
case DUK_TAG_POINTER: {
void *p = DUK_TVAL_GET_POINTER(tv);
return (p != NULL ? 1 : 0);
}
case DUK_TAG_LIGHTFUNC: {
return 1;
}
#if defined(DUK_USE_FASTINT)
case DUK_TAG_FASTINT:
if (DUK_TVAL_GET_FASTINT(tv) != 0) {
return 1;
} else {
return 0;
}
#endif
default: {
/* number */
duk_double_t d;
int c;
DUK_ASSERT(!DUK_TVAL_IS_UNUSED(tv));
DUK_ASSERT(DUK_TVAL_IS_DOUBLE(tv));
d = DUK_TVAL_GET_DOUBLE(tv);
c = DUK_FPCLASSIFY((double) d);
if (c == DUK_FP_ZERO || c == DUK_FP_NAN) {
return 0;
} else {
return 1;
}
}
}
DUK_UNREACHABLE();
}
duk_ret_t duk_bi_number_prototype_to_precision(duk_context *ctx) {
/* The specification has quite awkward order of coercion and
* checks for toPrecision(). The operations below are a bit
* reordered, within constraints of observable side effects.
*/
duk_double_t d;
duk_small_int_t prec;
duk_small_int_t c;
duk_small_uint_t n2s_flags;
DUK_ASSERT_TOP(ctx, 1);
d = duk__push_this_number_plain(ctx);
if (duk_is_undefined(ctx, 0)) {
goto use_to_string;
}
DUK_ASSERT_TOP(ctx, 2);
duk_to_int(ctx, 0); /* for side effects */
c = (duk_small_int_t) DUK_FPCLASSIFY(d);
if (c == DUK_FP_NAN || c == DUK_FP_INFINITE) {
goto use_to_string;
}
prec = (duk_small_int_t) duk_to_int_check_range(ctx, 0, 1, 21);
n2s_flags = DUK_N2S_FLAG_FIXED_FORMAT |
DUK_N2S_FLAG_NO_ZERO_PAD;
duk_numconv_stringify(ctx,
10 /*radix*/,
prec /*digits*/,
n2s_flags /*flags*/);
return 1;
use_to_string:
/* Used when precision is undefined; also used for NaN (-> "NaN"),
* and +/- infinity (-> "Infinity", "-Infinity").
*/
DUK_ASSERT_TOP(ctx, 2);
duk_to_string(ctx, -1);
return 1;
}
/* exposed, used by e.g. duk_bi_date.c */
DUK_INTERNAL duk_double_t duk_js_tointeger_number(duk_double_t x) {
duk_small_int_t c = (duk_small_int_t) DUK_FPCLASSIFY(x);
if (c == DUK_FP_NAN) {
return 0.0;
} else if (c == DUK_FP_ZERO || c == DUK_FP_INFINITE) {
/* XXX: FP_ZERO check can be removed, the else clause handles it
* correctly (preserving sign).
*/
return x;
} else {
duk_small_int_t s = (duk_small_int_t) DUK_SIGNBIT(x);
x = DUK_FLOOR(DUK_FABS(x)); /* truncate towards zero */
if (s) {
x = -x;
}
return x;
}
}
DUK_LOCAL double duk__round_fixed(double x) {
/* Numbers half-way between integers must be rounded towards +Infinity,
* e.g. -3.5 must be rounded to -3 (not -4). When rounded to zero, zero
* sign must be set appropriately. E5.1 Section 15.8.2.15.
*
* Note that ANSI C round() is "round to nearest integer, away from zero",
* which is incorrect for negative values. Here we make do with floor().
*/
duk_small_int_t c = (duk_small_int_t) DUK_FPCLASSIFY(x);
if (c == DUK_FP_NAN || c == DUK_FP_INFINITE || c == DUK_FP_ZERO) {
return x;
}
/*
* x is finite and non-zero
*
* -1.6 -> floor(-1.1) -> -2
* -1.5 -> floor(-1.0) -> -1 (towards +Inf)
* -1.4 -> floor(-0.9) -> -1
* -0.5 -> -0.0 (special case)
* -0.1 -> -0.0 (special case)
* +0.1 -> +0.0 (special case)
* +0.5 -> floor(+1.0) -> 1 (towards +Inf)
* +1.4 -> floor(+1.9) -> 1
* +1.5 -> floor(+2.0) -> 2 (towards +Inf)
* +1.6 -> floor(+2.1) -> 2
*/
if (x >= -0.5 && x < 0.5) {
/* +0.5 is handled by floor, this is on purpose */
if (x < 0.0) {
return -0.0;
} else {
return +0.0;
}
}
return DUK_FLOOR(x + 0.5);
}
duk_bool_t duk_js_toboolean(duk_tval *tv) {
switch (DUK_TVAL_GET_TAG(tv)) {
case DUK_TAG_UNDEFINED:
case DUK_TAG_NULL:
return 0;
case DUK_TAG_BOOLEAN:
return DUK_TVAL_GET_BOOLEAN(tv);
case DUK_TAG_STRING: {
duk_hstring *h = DUK_TVAL_GET_STRING(tv);
DUK_ASSERT(h != NULL);
return (h->blen > 0 ? 1 : 0);
}
case DUK_TAG_OBJECT: {
return 1;
}
case DUK_TAG_BUFFER: {
/* mimic semantics for strings */
duk_hbuffer *h = DUK_TVAL_GET_BUFFER(tv);
DUK_ASSERT(h != NULL);
return (DUK_HBUFFER_GET_SIZE(h) > 0 ? 1 : 0);
}
case DUK_TAG_POINTER: {
void *p = DUK_TVAL_GET_POINTER(tv);
return (p != NULL ? 1 : 0);
}
default: {
/* number */
int c;
DUK_ASSERT(DUK_TVAL_IS_NUMBER(tv));
c = DUK_FPCLASSIFY(DUK_TVAL_GET_NUMBER(tv));
if (c == DUK_FP_ZERO || c == DUK_FP_NAN) {
return 0;
} else {
return 1;
}
}
}
DUK_UNREACHABLE();
}
static double pow_fixed(double x, double y) {
/* The ANSI C pow() semantics differ from Ecmascript.
*
* E.g. when x==1 and y is +/- infinite, the Ecmascript required
* result is NaN, while at least Linux pow() returns 1.
*/
int cy;
cy = DUK_FPCLASSIFY(y);
if (cy == DUK_FP_NAN) {
goto ret_nan;
}
if (fabs(x) == 1.0 && cy == DUK_FP_INFINITE) {
goto ret_nan;
}
return pow(x, y);
ret_nan:
return DUK_DOUBLE_NAN;
}
DUK_LOCAL double duk__cbrt(double x) {
/* cbrt() is C99. To avoid hassling embedders with the need to provide a
* cube root function, we can get by with pow(). The result is not
* identical, but that's OK: ES2015 says it's implementation-dependent.
*/
#if defined(DUK_CBRT)
/* cbrt() matches ES2015 requirements. */
return DUK_CBRT(x);
#else
duk_small_int_t c = (duk_small_int_t) DUK_FPCLASSIFY(x);
/* pow() does not, however. */
if (c == DUK_FP_NAN || c == DUK_FP_INFINITE || c == DUK_FP_ZERO) {
return x;
}
if (DUK_SIGNBIT(x)) {
return -DUK_POW(-x, 1.0 / 3.0);
} else {
return DUK_POW(x, 1.0 / 3.0);
}
#endif
}
/* combined algorithm matching E5 Sections 9.5 and 9.6 */
DUK_LOCAL duk_double_t duk__toint32_touint32_helper(duk_double_t x, duk_bool_t is_toint32) {
duk_small_int_t c = (duk_small_int_t) DUK_FPCLASSIFY(x);
duk_small_int_t s;
if (c == DUK_FP_NAN || c == DUK_FP_ZERO || c == DUK_FP_INFINITE) {
return 0.0;
}
/* x = sign(x) * floor(abs(x)), i.e. truncate towards zero, keep sign */
s = (duk_small_int_t) DUK_SIGNBIT(x);
x = DUK_FLOOR(DUK_FABS(x));
if (s) {
x = -x;
}
/* NOTE: fmod(x) result sign is same as sign of x, which
* differs from what Javascript wants (see Section 9.6).
*/
x = DUK_FMOD(x, DUK_DOUBLE_2TO32); /* -> x in ]-2**32, 2**32[ */
if (x < 0.0) {
x += DUK_DOUBLE_2TO32;
}
/* -> x in [0, 2**32[ */
if (is_toint32) {
if (x >= DUK_DOUBLE_2TO31) {
/* x in [2**31, 2**32[ */
x -= DUK_DOUBLE_2TO32; /* -> x in [-2**31,2**31[ */
}
}
return x;
}
DUK_LOCAL duk_bool_t duk__js_equals_number(duk_double_t x, duk_double_t y) {
#if defined(DUK_USE_PARANOID_MATH)
/* Straightforward algorithm, makes fewer compiler assumptions. */
duk_small_int_t cx = (duk_small_int_t) DUK_FPCLASSIFY(x);
duk_small_int_t cy = (duk_small_int_t) DUK_FPCLASSIFY(y);
if (cx == DUK_FP_NAN || cy == DUK_FP_NAN) {
return 0;
}
if (cx == DUK_FP_ZERO && cy == DUK_FP_ZERO) {
return 1;
}
if (x == y) {
return 1;
}
return 0;
#else /* DUK_USE_PARANOID_MATH */
/* Better equivalent algorithm. If the compiler is compliant, C and
* Ecmascript semantics are identical for this particular comparison.
* In particular, NaNs must never compare equal and zeroes must compare
* equal regardless of sign. Could also use a macro, but this inlines
* already nicely (no difference on gcc, for instance).
*/
if (x == y) {
/* IEEE requires that NaNs compare false */
DUK_ASSERT(DUK_FPCLASSIFY(x) != DUK_FP_NAN);
DUK_ASSERT(DUK_FPCLASSIFY(y) != DUK_FP_NAN);
return 1;
} else {
/* IEEE requires that zeros compare the same regardless
* of their signed, so if both x and y are zeroes, they
* are caught above.
*/
DUK_ASSERT(!(DUK_FPCLASSIFY(x) == DUK_FP_ZERO && DUK_FPCLASSIFY(y) == DUK_FP_ZERO));
return 0;
}
#endif /* DUK_USE_PARANOID_MATH */
}
DUK_LOCAL duk_bool_t duk__js_samevalue_number(duk_double_t x, duk_double_t y) {
#if defined(DUK_USE_PARANOID_MATH)
duk_small_int_t cx = (duk_small_int_t) DUK_FPCLASSIFY(x);
duk_small_int_t cy = (duk_small_int_t) DUK_FPCLASSIFY(y);
if (cx == DUK_FP_NAN && cy == DUK_FP_NAN) {
/* SameValue(NaN, NaN) = true, regardless of NaN sign or extra bits */
return 1;
}
if (cx == DUK_FP_ZERO && cy == DUK_FP_ZERO) {
/* Note: cannot assume that a non-zero return value of signbit() would
* always be the same -- hence cannot (portably) use something like:
*
* signbit(x) == signbit(y)
*/
duk_small_int_t sx = (DUK_SIGNBIT(x) ? 1 : 0);
duk_small_int_t sy = (DUK_SIGNBIT(y) ? 1 : 0);
return (sx == sy);
}
/* normal comparison; known:
* - both x and y are not NaNs (but one of them can be)
* - both x and y are not zero (but one of them can be)
* - x and y may be denormal or infinite
*/
return (x == y);
#else /* DUK_USE_PARANOID_MATH */
duk_small_int_t cx = (duk_small_int_t) DUK_FPCLASSIFY(x);
duk_small_int_t cy = (duk_small_int_t) DUK_FPCLASSIFY(y);
if (x == y) {
/* IEEE requires that NaNs compare false */
DUK_ASSERT(DUK_FPCLASSIFY(x) != DUK_FP_NAN);
DUK_ASSERT(DUK_FPCLASSIFY(y) != DUK_FP_NAN);
/* Using classification has smaller footprint than direct comparison. */
if (DUK_UNLIKELY(cx == DUK_FP_ZERO && cy == DUK_FP_ZERO)) {
/* Note: cannot assume that a non-zero return value of signbit() would
* always be the same -- hence cannot (portably) use something like:
*
* signbit(x) == signbit(y)
*/
duk_small_int_t sx = (DUK_SIGNBIT(x) ? 1 : 0);
duk_small_int_t sy = (DUK_SIGNBIT(y) ? 1 : 0);
return (sx == sy);
}
return 1;
} else {
/* IEEE requires that zeros compare the same regardless
* of their signed, so if both x and y are zeroes, they
* are caught above.
*/
DUK_ASSERT(!(DUK_FPCLASSIFY(x) == DUK_FP_ZERO && DUK_FPCLASSIFY(y) == DUK_FP_ZERO));
/* Difference to non-strict/strict comparison is that NaNs compare
* equal and signed zero signs matter.
*/
if (DUK_UNLIKELY(cx == DUK_FP_NAN && cy == DUK_FP_NAN)) {
/* SameValue(NaN, NaN) = true, regardless of NaN sign or extra bits */
return 1;
}
return 0;
}
#endif /* DUK_USE_PARANOID_MATH */
}
DUK_INTERNAL duk_ret_t duk_bi_math_object_hypot(duk_context *ctx) {
/*
* E6 Section 20.2.2.18: Math.hypot
*
* - If no arguments are passed, the result is +0.
* - If any argument is +inf, the result is +inf.
* - If any argument is -inf, the result is +inf.
* - If no argument is +inf or -inf, and any argument is NaN, the result is
* NaN.
* - If all arguments are either +0 or -0, the result is +0.
*/
duk_idx_t nargs;
duk_idx_t i;
duk_bool_t found_nan;
duk_double_t max;
duk_double_t sum, summand;
duk_double_t comp, prelim;
duk_double_t t;
nargs = duk_get_top(ctx);
/* Find the highest value. Also ToNumber() coerces. */
max = 0.0;
found_nan = 0;
for (i = 0; i < nargs; i++) {
t = DUK_FABS(duk_to_number(ctx, i));
if (DUK_FPCLASSIFY(t) == DUK_FP_NAN) {
found_nan = 1;
} else {
max = duk_double_fmax(max, t);
}
}
/* Early return cases. */
if (max == DUK_DOUBLE_INFINITY) {
duk_push_number(ctx, DUK_DOUBLE_INFINITY);
return 1;
} else if (found_nan) {
duk_push_number(ctx, DUK_DOUBLE_NAN);
return 1;
} else if (max == 0.0) {
duk_push_number(ctx, 0.0);
/* Otherwise we'd divide by zero. */
return 1;
}
/* Use Kahan summation and normalize to the highest value to minimize
* floating point rounding error and avoid overflow.
*
* https://en.wikipedia.org/wiki/Kahan_summation_algorithm
*/
sum = 0.0;
comp = 0.0;
for (i = 0; i < nargs; i++) {
t = DUK_FABS(duk_get_number(ctx, i)) / max;
summand = (t * t) - comp;
prelim = sum + summand;
comp = (prelim - sum) - summand;
sum = prelim;
}
duk_push_number(ctx, (duk_double_t) DUK_SQRT(sum) * max);
return 1;
}
duk_bool_t duk_js_compare_helper(duk_hthread *thr, duk_tval *tv_x, duk_tval *tv_y, duk_small_int_t flags) {
duk_context *ctx = (duk_context *) thr;
duk_double_t d1, d2;
duk_small_int_t c1, c2;
duk_small_int_t s1, s2;
duk_small_int_t rc;
duk_bool_t retval;
duk_push_tval(ctx, tv_x);
duk_push_tval(ctx, tv_y);
if (flags & DUK_COMPARE_FLAG_EVAL_LEFT_FIRST) {
duk_to_primitive(ctx, -2, DUK_HINT_NUMBER);
duk_to_primitive(ctx, -1, DUK_HINT_NUMBER);
} else {
duk_to_primitive(ctx, -1, DUK_HINT_NUMBER);
duk_to_primitive(ctx, -2, DUK_HINT_NUMBER);
}
/* Note: reuse variables */
tv_x = duk_get_tval(ctx, -2);
tv_y = duk_get_tval(ctx, -1);
if (DUK_TVAL_IS_STRING(tv_x) && DUK_TVAL_IS_STRING(tv_y)) {
duk_hstring *h1 = DUK_TVAL_GET_STRING(tv_x);
duk_hstring *h2 = DUK_TVAL_GET_STRING(tv_y);
DUK_ASSERT(h1 != NULL);
DUK_ASSERT(h2 != NULL);
rc = duk_js_string_compare(h1, h2);
if (rc < 0) {
goto lt_true;
} else {
goto lt_false;
}
} else {
/* Ordering should not matter (E5 Section 11.8.5, step 3.a) but
* preserve it just in case.
*/
if (flags & DUK_COMPARE_FLAG_EVAL_LEFT_FIRST) {
d1 = duk_to_number(ctx, -2);
d2 = duk_to_number(ctx, -1);
} else {
d2 = duk_to_number(ctx, -1);
d1 = duk_to_number(ctx, -2);
}
c1 = (duk_small_int_t) DUK_FPCLASSIFY(d1);
s1 = (duk_small_int_t) DUK_SIGNBIT(d1);
c2 = (duk_small_int_t) DUK_FPCLASSIFY(d2);
s2 = (duk_small_int_t) DUK_SIGNBIT(d2);
if (c1 == DUK_FP_NAN || c2 == DUK_FP_NAN) {
goto lt_undefined;
}
if (c1 == DUK_FP_ZERO && c2 == DUK_FP_ZERO) {
/* For all combinations: +0 < +0, +0 < -0, -0 < +0, -0 < -0,
* steps e, f, and g.
*/
goto lt_false;
}
if (d1 == d2) {
goto lt_false;
}
if (c1 == DUK_FP_INFINITE && s1 == 0) {
/* x == +Infinity */
goto lt_false;
}
if (c2 == DUK_FP_INFINITE && s2 == 0) {
/* y == +Infinity */
goto lt_true;
}
if (c2 == DUK_FP_INFINITE && s2 != 0) {
/* y == -Infinity */
goto lt_false;
}
if (c1 == DUK_FP_INFINITE && s1 != 0) {
/* x == -Infinity */
goto lt_true;
}
if (d1 < d2) {
goto lt_true;
}
goto lt_false;
}
lt_undefined:
/* Note: undefined from Section 11.8.5 always results in false
* return (see e.g. Section 11.8.3) - hence special treatment here.
*/
retval = 0;
goto cleanup;
lt_true:
if (flags & DUK_COMPARE_FLAG_NEGATE) {
retval = 0;
goto cleanup;
} else {
retval = 1;
goto cleanup;
}
/* never here */
lt_false:
if (flags & DUK_COMPARE_FLAG_NEGATE) {
retval = 1;
goto cleanup;
} else {
retval = 0;
goto cleanup;
}
/* never here */
cleanup:
duk_pop_2(ctx);
return retval;
}
static double duk__pow_fixed(double x, double y) {
/* The ANSI C pow() semantics differ from Ecmascript.
*
* E.g. when x==1 and y is +/- infinite, the Ecmascript required
* result is NaN, while at least Linux pow() returns 1.
*/
int cx, cy, sx;
DUK_UNREF(cx);
DUK_UNREF(sx);
cy = DUK_FPCLASSIFY(y);
if (cy == DUK_FP_NAN) {
goto ret_nan;
}
if (DUK_FABS(x) == 1.0 && cy == DUK_FP_INFINITE) {
goto ret_nan;
}
#if defined(DUK_USE_POW_NETBSD_WORKAROUND)
/* See test-bug-netbsd-math-pow.js: NetBSD 6.0 on x86 (at least) does not
* correctly handle some cases where x=+/-0. Specific fixes to these
* here.
*/
cx = DUK_FPCLASSIFY(x);
if (cx == DUK_FP_ZERO && y < 0.0) {
sx = DUK_SIGNBIT(x);
if (sx == 0) {
/* Math.pow(+0,y) should be Infinity when y<0. NetBSD pow()
* returns -Infinity instead when y is <0 and finite. The
* if-clause also catches y == -Infinity (which works even
* without the fix).
*/
return DUK_DOUBLE_INFINITY;
} else {
/* Math.pow(-0,y) where y<0 should be:
* - -Infinity if y<0 and an odd integer
* - Infinity otherwise
* NetBSD pow() returns -Infinity for all finite y<0. The
* if-clause also catches y == -Infinity (which works even
* without the fix).
*/
/* fmod() return value has same sign as input (negative) so
* the result here will be in the range ]-2,0], 1 indicates
* odd. If x is -Infinity, NaN is returned and the odd check
* always concludes "not odd" which results in desired outcome.
*/
double tmp = DUK_FMOD(y, 2);
if (tmp == -1.0) {
return -DUK_DOUBLE_INFINITY;
} else {
/* Not odd, or y == -Infinity */
return DUK_DOUBLE_INFINITY;
}
}
}
#endif
return DUK_POW(x, y);
ret_nan:
return DUK_DOUBLE_NAN;
}
DUK_INTERNAL duk_bool_t duk_js_compare_helper(duk_hthread *thr, duk_tval *tv_x, duk_tval *tv_y, duk_small_int_t flags) {
duk_context *ctx = (duk_context *) thr;
duk_double_t d1, d2;
duk_small_int_t c1, c2;
duk_small_int_t s1, s2;
duk_small_int_t rc;
duk_bool_t retval;
/* Fast path for fastints */
#if defined(DUK_USE_FASTINT)
if (DUK_TVAL_IS_FASTINT(tv_x) && DUK_TVAL_IS_FASTINT(tv_y)) {
duk_int64_t v1 = DUK_TVAL_GET_FASTINT(tv_x);
duk_int64_t v2 = DUK_TVAL_GET_FASTINT(tv_y);
if (v1 < v2) {
/* 'lt is true' */
retval = 1;
} else {
retval = 0;
}
if (flags & DUK_COMPARE_FLAG_NEGATE) {
retval ^= 1;
}
return retval;
}
#endif /* DUK_USE_FASTINT */
/* Fast path for numbers (one of which may be a fastint) */
#if 1 /* XXX: make fast paths optional for size minimization? */
if (DUK_TVAL_IS_NUMBER(tv_x) && DUK_TVAL_IS_NUMBER(tv_y)) {
d1 = DUK_TVAL_GET_NUMBER(tv_x);
d2 = DUK_TVAL_GET_NUMBER(tv_y);
c1 = DUK_FPCLASSIFY(d1);
c2 = DUK_FPCLASSIFY(d2);
if (c1 == DUK_FP_NORMAL && c2 == DUK_FP_NORMAL) {
/* XXX: this is a very narrow check, and doesn't cover
* zeroes, subnormals, infinities, which compare normally.
*/
if (d1 < d2) {
/* 'lt is true' */
retval = 1;
} else {
retval = 0;
}
if (flags & DUK_COMPARE_FLAG_NEGATE) {
retval ^= 1;
}
return retval;
}
}
#endif
/* Slow path */
duk_push_tval(ctx, tv_x);
duk_push_tval(ctx, tv_y);
if (flags & DUK_COMPARE_FLAG_EVAL_LEFT_FIRST) {
duk_to_primitive(ctx, -2, DUK_HINT_NUMBER);
duk_to_primitive(ctx, -1, DUK_HINT_NUMBER);
} else {
duk_to_primitive(ctx, -1, DUK_HINT_NUMBER);
duk_to_primitive(ctx, -2, DUK_HINT_NUMBER);
}
/* Note: reuse variables */
tv_x = duk_get_tval(ctx, -2);
tv_y = duk_get_tval(ctx, -1);
if (DUK_TVAL_IS_STRING(tv_x) && DUK_TVAL_IS_STRING(tv_y)) {
duk_hstring *h1 = DUK_TVAL_GET_STRING(tv_x);
duk_hstring *h2 = DUK_TVAL_GET_STRING(tv_y);
DUK_ASSERT(h1 != NULL);
DUK_ASSERT(h2 != NULL);
rc = duk_js_string_compare(h1, h2);
if (rc < 0) {
goto lt_true;
} else {
goto lt_false;
}
} else {
/* Ordering should not matter (E5 Section 11.8.5, step 3.a) but
* preserve it just in case.
*/
if (flags & DUK_COMPARE_FLAG_EVAL_LEFT_FIRST) {
d1 = duk_to_number(ctx, -2);
d2 = duk_to_number(ctx, -1);
} else {
d2 = duk_to_number(ctx, -1);
d1 = duk_to_number(ctx, -2);
}
c1 = (duk_small_int_t) DUK_FPCLASSIFY(d1);
s1 = (duk_small_int_t) DUK_SIGNBIT(d1);
c2 = (duk_small_int_t) DUK_FPCLASSIFY(d2);
s2 = (duk_small_int_t) DUK_SIGNBIT(d2);
if (c1 == DUK_FP_NAN || c2 == DUK_FP_NAN) {
goto lt_undefined;
}
if (c1 == DUK_FP_ZERO && c2 == DUK_FP_ZERO) {
/* For all combinations: +0 < +0, +0 < -0, -0 < +0, -0 < -0,
* steps e, f, and g.
*/
goto lt_false;
}
if (d1 == d2) {
goto lt_false;
}
if (c1 == DUK_FP_INFINITE && s1 == 0) {
/* x == +Infinity */
goto lt_false;
}
if (c2 == DUK_FP_INFINITE && s2 == 0) {
/* y == +Infinity */
goto lt_true;
}
if (c2 == DUK_FP_INFINITE && s2 != 0) {
/* y == -Infinity */
goto lt_false;
}
if (c1 == DUK_FP_INFINITE && s1 != 0) {
/* x == -Infinity */
goto lt_true;
}
if (d1 < d2) {
goto lt_true;
}
goto lt_false;
}
lt_undefined:
/* Note: undefined from Section 11.8.5 always results in false
* return (see e.g. Section 11.8.3) - hence special treatment here.
*/
retval = 0;
goto cleanup;
lt_true:
if (flags & DUK_COMPARE_FLAG_NEGATE) {
retval = 0;
goto cleanup;
} else {
retval = 1;
goto cleanup;
}
/* never here */
lt_false:
if (flags & DUK_COMPARE_FLAG_NEGATE) {
retval = 1;
goto cleanup;
} else {
retval = 0;
goto cleanup;
}
/* never here */
cleanup:
duk_pop_2(ctx);
return retval;
}
int duk_repl_isinf(double x) {
int c = DUK_FPCLASSIFY(x);
return (c == DUK_FP_INFINITE);
}
int duk_repl_isnan(double x) {
int c = DUK_FPCLASSIFY(x);
return (c == DUK_FP_NAN);
}
