コード例 #1
0
ファイル: duk_bi_math.c プロジェクト: harold-b/duktape
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);
}
コード例 #2
0
ファイル: duk_bi_math.c プロジェクト: harold-b/duktape
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);
}
コード例 #3
0
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
}
コード例 #4
0
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
}
コード例 #5
0
ファイル: duk_js_ops.c プロジェクト: bihai/duk4vb
/* 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;
	}
}
コード例 #6
0
ファイル: duk_bi_math.c プロジェクト: harold-b/duktape
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
}
コード例 #7
0
ファイル: duk_js_ops.c プロジェクト: bihai/duk4vb
/* 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;
}
コード例 #8
0
ファイル: duk_js_ops.c プロジェクト: bihai/duk4vb
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;
}
コード例 #9
0
ファイル: duk_js_ops.c プロジェクト: bihai/duk4vb
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 */
}
コード例 #10
0
ファイル: duk_bi_math.c プロジェクト: rockybars/duktape
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;
}
コード例 #11
0
ファイル: duk_js_ops.c プロジェクト: cherry-wb/duktape
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;
}