DUK_LOCAL double duk__atan2_fixed(double x, double y) { #if defined(DUK_USE_ATAN2_WORKAROUNDS) /* Specific fixes to common atan2() implementation issues: * - test-bug-mingw-math-issues.js */ if (DUK_ISINF(x) && DUK_ISINF(y)) { if (DUK_SIGNBIT(x)) { if (DUK_SIGNBIT(y)) { return -2.356194490192345; } else { return -0.7853981633974483; } } else { if (DUK_SIGNBIT(y)) { return 2.356194490192345; } else { return 0.7853981633974483; } } } #else /* Some ISO C assumptions. */ DUK_ASSERT(DUK_ATAN2(DUK_DOUBLE_INFINITY, DUK_DOUBLE_INFINITY) == 0.7853981633974483); DUK_ASSERT(DUK_ATAN2(-DUK_DOUBLE_INFINITY, DUK_DOUBLE_INFINITY) == -0.7853981633974483); DUK_ASSERT(DUK_ATAN2(DUK_DOUBLE_INFINITY, -DUK_DOUBLE_INFINITY) == 2.356194490192345); DUK_ASSERT(DUK_ATAN2(-DUK_DOUBLE_INFINITY, -DUK_DOUBLE_INFINITY) == -2.356194490192345); #endif return DUK_ATAN2(x, y); }
DUK_LOCAL double duk__fmax_fixed(double x, double y) { /* fmax() with args -0 and +0 is not guaranteed to return * +0 as Ecmascript requires. */ if (x == 0 && y == 0) { if (DUK_SIGNBIT(x) == 0 || DUK_SIGNBIT(y) == 0) { return +0.0; } else { return -0.0; } } return duk_double_fmax(x, y); }
static double fmax_fixed(double x, double y) { /* fmax() with args -0 and +0 is not guaranteed to return * +0 as Ecmascript requires. */ if (x == 0 && y == 0) { if (DUK_SIGNBIT(x) == 0 || DUK_SIGNBIT(y) == 0) { return +0.0; } else { return -0.0; } } #ifdef DUK_USE_MATH_FMAX return fmax(x, y); #else return (x > y ? x : y); #endif }
static double fmin_fixed(double x, double y) { /* fmin() with args -0 and +0 is not guaranteed to return * -0 as Ecmascript requires. */ if (x == 0 && y == 0) { /* XXX: what's the safest way of creating a negative zero? */ if (DUK_SIGNBIT(x) != 0 || DUK_SIGNBIT(y) != 0) { return -0.0; } else { return +0.0; } } #ifdef DUK_USE_MATH_FMIN return fmin(x, y); #else return (x < y ? x : y); #endif }
/* 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__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_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; }
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 */ }
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_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; }