diff options
Diffstat (limited to 'intl/icu/source/i18n/number_decimalquantity.cpp')
-rw-r--r-- | intl/icu/source/i18n/number_decimalquantity.cpp | 1347 |
1 files changed, 1347 insertions, 0 deletions
diff --git a/intl/icu/source/i18n/number_decimalquantity.cpp b/intl/icu/source/i18n/number_decimalquantity.cpp new file mode 100644 index 0000000000..482e93dc7a --- /dev/null +++ b/intl/icu/source/i18n/number_decimalquantity.cpp @@ -0,0 +1,1347 @@ +// © 2017 and later: Unicode, Inc. and others. +// License & terms of use: http://www.unicode.org/copyright.html + +#include "unicode/utypes.h" + +#if !UCONFIG_NO_FORMATTING + +#include <cstdlib> +#include <cmath> +#include <limits> +#include <stdlib.h> + +#include "unicode/plurrule.h" +#include "cmemory.h" +#include "number_decnum.h" +#include "putilimp.h" +#include "number_decimalquantity.h" +#include "number_roundingutils.h" +#include "double-conversion.h" +#include "charstr.h" +#include "number_utils.h" +#include "uassert.h" + +using namespace icu; +using namespace icu::number; +using namespace icu::number::impl; + +using icu::double_conversion::DoubleToStringConverter; +using icu::double_conversion::StringToDoubleConverter; + +namespace { + +int8_t NEGATIVE_FLAG = 1; +int8_t INFINITY_FLAG = 2; +int8_t NAN_FLAG = 4; + +/** Helper function for safe subtraction (no overflow). */ +inline int32_t safeSubtract(int32_t a, int32_t b) { + // Note: In C++, signed integer subtraction is undefined behavior. + int32_t diff = static_cast<int32_t>(static_cast<uint32_t>(a) - static_cast<uint32_t>(b)); + if (b < 0 && diff < a) { return INT32_MAX; } + if (b > 0 && diff > a) { return INT32_MIN; } + return diff; +} + +static double DOUBLE_MULTIPLIERS[] = { + 1e0, + 1e1, + 1e2, + 1e3, + 1e4, + 1e5, + 1e6, + 1e7, + 1e8, + 1e9, + 1e10, + 1e11, + 1e12, + 1e13, + 1e14, + 1e15, + 1e16, + 1e17, + 1e18, + 1e19, + 1e20, + 1e21}; + +} // namespace + +icu::IFixedDecimal::~IFixedDecimal() = default; + +DecimalQuantity::DecimalQuantity() { + setBcdToZero(); + flags = 0; +} + +DecimalQuantity::~DecimalQuantity() { + if (usingBytes) { + uprv_free(fBCD.bcdBytes.ptr); + fBCD.bcdBytes.ptr = nullptr; + usingBytes = false; + } +} + +DecimalQuantity::DecimalQuantity(const DecimalQuantity &other) { + *this = other; +} + +DecimalQuantity::DecimalQuantity(DecimalQuantity&& src) U_NOEXCEPT { + *this = std::move(src); +} + +DecimalQuantity &DecimalQuantity::operator=(const DecimalQuantity &other) { + if (this == &other) { + return *this; + } + copyBcdFrom(other); + copyFieldsFrom(other); + return *this; +} + +DecimalQuantity& DecimalQuantity::operator=(DecimalQuantity&& src) U_NOEXCEPT { + if (this == &src) { + return *this; + } + moveBcdFrom(src); + copyFieldsFrom(src); + return *this; +} + +void DecimalQuantity::copyFieldsFrom(const DecimalQuantity& other) { + bogus = other.bogus; + lReqPos = other.lReqPos; + rReqPos = other.rReqPos; + scale = other.scale; + precision = other.precision; + flags = other.flags; + origDouble = other.origDouble; + origDelta = other.origDelta; + isApproximate = other.isApproximate; + exponent = other.exponent; +} + +void DecimalQuantity::clear() { + lReqPos = 0; + rReqPos = 0; + flags = 0; + setBcdToZero(); // sets scale, precision, hasDouble, origDouble, origDelta, and BCD data +} + +void DecimalQuantity::setMinInteger(int32_t minInt) { + // Validation should happen outside of DecimalQuantity, e.g., in the Precision class. + U_ASSERT(minInt >= 0); + + // Special behavior: do not set minInt to be less than what is already set. + // This is so significant digits rounding can set the integer length. + if (minInt < lReqPos) { + minInt = lReqPos; + } + + // Save values into internal state + lReqPos = minInt; +} + +void DecimalQuantity::setMinFraction(int32_t minFrac) { + // Validation should happen outside of DecimalQuantity, e.g., in the Precision class. + U_ASSERT(minFrac >= 0); + + // Save values into internal state + // Negation is safe for minFrac/maxFrac because -Integer.MAX_VALUE > Integer.MIN_VALUE + rReqPos = -minFrac; +} + +void DecimalQuantity::applyMaxInteger(int32_t maxInt) { + // Validation should happen outside of DecimalQuantity, e.g., in the Precision class. + U_ASSERT(maxInt >= 0); + + if (precision == 0) { + return; + } + + if (maxInt <= scale) { + setBcdToZero(); + return; + } + + int32_t magnitude = getMagnitude(); + if (maxInt <= magnitude) { + popFromLeft(magnitude - maxInt + 1); + compact(); + } +} + +uint64_t DecimalQuantity::getPositionFingerprint() const { + uint64_t fingerprint = 0; + fingerprint ^= (lReqPos << 16); + fingerprint ^= (static_cast<uint64_t>(rReqPos) << 32); + return fingerprint; +} + +void DecimalQuantity::roundToIncrement(double roundingIncrement, RoundingMode roundingMode, + UErrorCode& status) { + // Do not call this method with an increment having only a 1 or a 5 digit! + // Use a more efficient call to either roundToMagnitude() or roundToNickel(). + // Check a few popular rounding increments; a more thorough check is in Java. + U_ASSERT(roundingIncrement != 0.01); + U_ASSERT(roundingIncrement != 0.05); + U_ASSERT(roundingIncrement != 0.1); + U_ASSERT(roundingIncrement != 0.5); + U_ASSERT(roundingIncrement != 1); + U_ASSERT(roundingIncrement != 5); + + DecNum incrementDN; + incrementDN.setTo(roundingIncrement, status); + if (U_FAILURE(status)) { return; } + + // Divide this DecimalQuantity by the increment, round, then multiply back. + divideBy(incrementDN, status); + if (U_FAILURE(status)) { return; } + roundToMagnitude(0, roundingMode, status); + if (U_FAILURE(status)) { return; } + multiplyBy(incrementDN, status); + if (U_FAILURE(status)) { return; } +} + +void DecimalQuantity::multiplyBy(const DecNum& multiplicand, UErrorCode& status) { + if (isZeroish()) { + return; + } + // Convert to DecNum, multiply, and convert back. + DecNum decnum; + toDecNum(decnum, status); + if (U_FAILURE(status)) { return; } + decnum.multiplyBy(multiplicand, status); + if (U_FAILURE(status)) { return; } + setToDecNum(decnum, status); +} + +void DecimalQuantity::divideBy(const DecNum& divisor, UErrorCode& status) { + if (isZeroish()) { + return; + } + // Convert to DecNum, multiply, and convert back. + DecNum decnum; + toDecNum(decnum, status); + if (U_FAILURE(status)) { return; } + decnum.divideBy(divisor, status); + if (U_FAILURE(status)) { return; } + setToDecNum(decnum, status); +} + +void DecimalQuantity::negate() { + flags ^= NEGATIVE_FLAG; +} + +int32_t DecimalQuantity::getMagnitude() const { + U_ASSERT(precision != 0); + return scale + precision - 1; +} + +bool DecimalQuantity::adjustMagnitude(int32_t delta) { + if (precision != 0) { + // i.e., scale += delta; origDelta += delta + bool overflow = uprv_add32_overflow(scale, delta, &scale); + overflow = uprv_add32_overflow(origDelta, delta, &origDelta) || overflow; + // Make sure that precision + scale won't overflow, either + int32_t dummy; + overflow = overflow || uprv_add32_overflow(scale, precision, &dummy); + return overflow; + } + return false; +} + +double DecimalQuantity::getPluralOperand(PluralOperand operand) const { + // If this assertion fails, you need to call roundToInfinity() or some other rounding method. + // See the comment at the top of this file explaining the "isApproximate" field. + U_ASSERT(!isApproximate); + + switch (operand) { + case PLURAL_OPERAND_I: + // Invert the negative sign if necessary + return static_cast<double>(isNegative() ? -toLong(true) : toLong(true)); + case PLURAL_OPERAND_F: + return static_cast<double>(toFractionLong(true)); + case PLURAL_OPERAND_T: + return static_cast<double>(toFractionLong(false)); + case PLURAL_OPERAND_V: + return fractionCount(); + case PLURAL_OPERAND_W: + return fractionCountWithoutTrailingZeros(); + case PLURAL_OPERAND_E: + return static_cast<double>(getExponent()); + default: + return std::abs(toDouble()); + } +} + +int32_t DecimalQuantity::getExponent() const { + return exponent; +} + +void DecimalQuantity::adjustExponent(int delta) { + exponent = exponent + delta; +} + +bool DecimalQuantity::hasIntegerValue() const { + return scale >= 0; +} + +int32_t DecimalQuantity::getUpperDisplayMagnitude() const { + // If this assertion fails, you need to call roundToInfinity() or some other rounding method. + // See the comment in the header file explaining the "isApproximate" field. + U_ASSERT(!isApproximate); + + int32_t magnitude = scale + precision; + int32_t result = (lReqPos > magnitude) ? lReqPos : magnitude; + return result - 1; +} + +int32_t DecimalQuantity::getLowerDisplayMagnitude() const { + // If this assertion fails, you need to call roundToInfinity() or some other rounding method. + // See the comment in the header file explaining the "isApproximate" field. + U_ASSERT(!isApproximate); + + int32_t magnitude = scale; + int32_t result = (rReqPos < magnitude) ? rReqPos : magnitude; + return result; +} + +int8_t DecimalQuantity::getDigit(int32_t magnitude) const { + // If this assertion fails, you need to call roundToInfinity() or some other rounding method. + // See the comment at the top of this file explaining the "isApproximate" field. + U_ASSERT(!isApproximate); + + return getDigitPos(magnitude - scale); +} + +int32_t DecimalQuantity::fractionCount() const { + int32_t fractionCountWithExponent = -getLowerDisplayMagnitude() - exponent; + return fractionCountWithExponent > 0 ? fractionCountWithExponent : 0; +} + +int32_t DecimalQuantity::fractionCountWithoutTrailingZeros() const { + int32_t fractionCountWithExponent = -scale - exponent; + return fractionCountWithExponent > 0 ? fractionCountWithExponent : 0; // max(-fractionCountWithExponent, 0) +} + +bool DecimalQuantity::isNegative() const { + return (flags & NEGATIVE_FLAG) != 0; +} + +Signum DecimalQuantity::signum() const { + bool isZero = (isZeroish() && !isInfinite()); + bool isNeg = isNegative(); + if (isZero && isNeg) { + return SIGNUM_NEG_ZERO; + } else if (isZero) { + return SIGNUM_POS_ZERO; + } else if (isNeg) { + return SIGNUM_NEG; + } else { + return SIGNUM_POS; + } +} + +bool DecimalQuantity::isInfinite() const { + return (flags & INFINITY_FLAG) != 0; +} + +bool DecimalQuantity::isNaN() const { + return (flags & NAN_FLAG) != 0; +} + +bool DecimalQuantity::isZeroish() const { + return precision == 0; +} + +DecimalQuantity &DecimalQuantity::setToInt(int32_t n) { + setBcdToZero(); + flags = 0; + if (n == INT32_MIN) { + flags |= NEGATIVE_FLAG; + // leave as INT32_MIN; handled below in _setToInt() + } else if (n < 0) { + flags |= NEGATIVE_FLAG; + n = -n; + } + if (n != 0) { + _setToInt(n); + compact(); + } + return *this; +} + +void DecimalQuantity::_setToInt(int32_t n) { + if (n == INT32_MIN) { + readLongToBcd(-static_cast<int64_t>(n)); + } else { + readIntToBcd(n); + } +} + +DecimalQuantity &DecimalQuantity::setToLong(int64_t n) { + setBcdToZero(); + flags = 0; + if (n < 0 && n > INT64_MIN) { + flags |= NEGATIVE_FLAG; + n = -n; + } + if (n != 0) { + _setToLong(n); + compact(); + } + return *this; +} + +void DecimalQuantity::_setToLong(int64_t n) { + if (n == INT64_MIN) { + DecNum decnum; + UErrorCode localStatus = U_ZERO_ERROR; + decnum.setTo("9.223372036854775808E+18", localStatus); + if (U_FAILURE(localStatus)) { return; } // unexpected + flags |= NEGATIVE_FLAG; + readDecNumberToBcd(decnum); + } else if (n <= INT32_MAX) { + readIntToBcd(static_cast<int32_t>(n)); + } else { + readLongToBcd(n); + } +} + +DecimalQuantity &DecimalQuantity::setToDouble(double n) { + setBcdToZero(); + flags = 0; + // signbit() from <math.h> handles +0.0 vs -0.0 + if (std::signbit(n)) { + flags |= NEGATIVE_FLAG; + n = -n; + } + if (std::isnan(n) != 0) { + flags |= NAN_FLAG; + } else if (std::isfinite(n) == 0) { + flags |= INFINITY_FLAG; + } else if (n != 0) { + _setToDoubleFast(n); + compact(); + } + return *this; +} + +void DecimalQuantity::_setToDoubleFast(double n) { + isApproximate = true; + origDouble = n; + origDelta = 0; + + // Make sure the double is an IEEE 754 double. If not, fall back to the slow path right now. + // TODO: Make a fast path for other types of doubles. + if (!std::numeric_limits<double>::is_iec559) { + convertToAccurateDouble(); + return; + } + + // To get the bits from the double, use memcpy, which takes care of endianness. + uint64_t ieeeBits; + uprv_memcpy(&ieeeBits, &n, sizeof(n)); + int32_t exponent = static_cast<int32_t>((ieeeBits & 0x7ff0000000000000L) >> 52) - 0x3ff; + + // Not all integers can be represented exactly for exponent > 52 + if (exponent <= 52 && static_cast<int64_t>(n) == n) { + _setToLong(static_cast<int64_t>(n)); + return; + } + + if (exponent == -1023 || exponent == 1024) { + // The extreme values of exponent are special; use slow path. + convertToAccurateDouble(); + return; + } + + // 3.3219... is log2(10) + auto fracLength = static_cast<int32_t> ((52 - exponent) / 3.32192809488736234787031942948939017586); + if (fracLength >= 0) { + int32_t i = fracLength; + // 1e22 is the largest exact double. + for (; i >= 22; i -= 22) n *= 1e22; + n *= DOUBLE_MULTIPLIERS[i]; + } else { + int32_t i = fracLength; + // 1e22 is the largest exact double. + for (; i <= -22; i += 22) n /= 1e22; + n /= DOUBLE_MULTIPLIERS[-i]; + } + auto result = static_cast<int64_t>(uprv_round(n)); + if (result != 0) { + _setToLong(result); + scale -= fracLength; + } +} + +void DecimalQuantity::convertToAccurateDouble() { + U_ASSERT(origDouble != 0); + int32_t delta = origDelta; + + // Call the slow oracle function (Double.toString in Java, DoubleToAscii in C++). + char buffer[DoubleToStringConverter::kBase10MaximalLength + 1]; + bool sign; // unused; always positive + int32_t length; + int32_t point; + DoubleToStringConverter::DoubleToAscii( + origDouble, + DoubleToStringConverter::DtoaMode::SHORTEST, + 0, + buffer, + sizeof(buffer), + &sign, + &length, + &point + ); + + setBcdToZero(); + readDoubleConversionToBcd(buffer, length, point); + scale += delta; + explicitExactDouble = true; +} + +DecimalQuantity &DecimalQuantity::setToDecNumber(StringPiece n, UErrorCode& status) { + setBcdToZero(); + flags = 0; + + // Compute the decNumber representation + DecNum decnum; + decnum.setTo(n, status); + + _setToDecNum(decnum, status); + return *this; +} + +DecimalQuantity& DecimalQuantity::setToDecNum(const DecNum& decnum, UErrorCode& status) { + setBcdToZero(); + flags = 0; + + _setToDecNum(decnum, status); + return *this; +} + +void DecimalQuantity::_setToDecNum(const DecNum& decnum, UErrorCode& status) { + if (U_FAILURE(status)) { return; } + if (decnum.isNegative()) { + flags |= NEGATIVE_FLAG; + } + if (!decnum.isZero()) { + readDecNumberToBcd(decnum); + compact(); + } +} + +int64_t DecimalQuantity::toLong(bool truncateIfOverflow) const { + // NOTE: Call sites should be guarded by fitsInLong(), like this: + // if (dq.fitsInLong()) { /* use dq.toLong() */ } else { /* use some fallback */ } + // Fallback behavior upon truncateIfOverflow is to truncate at 17 digits. + uint64_t result = 0L; + int32_t upperMagnitude = exponent + scale + precision - 1; + if (truncateIfOverflow) { + upperMagnitude = std::min(upperMagnitude, 17); + } + for (int32_t magnitude = upperMagnitude; magnitude >= 0; magnitude--) { + result = result * 10 + getDigitPos(magnitude - scale - exponent); + } + if (isNegative()) { + return static_cast<int64_t>(0LL - result); // i.e., -result + } + return static_cast<int64_t>(result); +} + +uint64_t DecimalQuantity::toFractionLong(bool includeTrailingZeros) const { + uint64_t result = 0L; + int32_t magnitude = -1 - exponent; + int32_t lowerMagnitude = scale; + if (includeTrailingZeros) { + lowerMagnitude = std::min(lowerMagnitude, rReqPos); + } + for (; magnitude >= lowerMagnitude && result <= 1e18L; magnitude--) { + result = result * 10 + getDigitPos(magnitude - scale); + } + // Remove trailing zeros; this can happen during integer overflow cases. + if (!includeTrailingZeros) { + while (result > 0 && (result % 10) == 0) { + result /= 10; + } + } + return result; +} + +bool DecimalQuantity::fitsInLong(bool ignoreFraction) const { + if (isInfinite() || isNaN()) { + return false; + } + if (isZeroish()) { + return true; + } + if (exponent + scale < 0 && !ignoreFraction) { + return false; + } + int magnitude = getMagnitude(); + if (magnitude < 18) { + return true; + } + if (magnitude > 18) { + return false; + } + // Hard case: the magnitude is 10^18. + // The largest int64 is: 9,223,372,036,854,775,807 + for (int p = 0; p < precision; p++) { + int8_t digit = getDigit(18 - p); + static int8_t INT64_BCD[] = { 9, 2, 2, 3, 3, 7, 2, 0, 3, 6, 8, 5, 4, 7, 7, 5, 8, 0, 8 }; + if (digit < INT64_BCD[p]) { + return true; + } else if (digit > INT64_BCD[p]) { + return false; + } + } + // Exactly equal to max long plus one. + return isNegative(); +} + +double DecimalQuantity::toDouble() const { + // If this assertion fails, you need to call roundToInfinity() or some other rounding method. + // See the comment in the header file explaining the "isApproximate" field. + U_ASSERT(!isApproximate); + + if (isNaN()) { + return NAN; + } else if (isInfinite()) { + return isNegative() ? -INFINITY : INFINITY; + } + + // We are processing well-formed input, so we don't need any special options to StringToDoubleConverter. + StringToDoubleConverter converter(0, 0, 0, "", ""); + UnicodeString numberString = this->toScientificString(); + int32_t count; + return converter.StringToDouble( + reinterpret_cast<const uint16_t*>(numberString.getBuffer()), + numberString.length(), + &count); +} + +void DecimalQuantity::toDecNum(DecNum& output, UErrorCode& status) const { + // Special handling for zero + if (precision == 0) { + output.setTo("0", status); + } + + // Use the BCD constructor. We need to do a little bit of work to convert, though. + // The decNumber constructor expects most-significant first, but we store least-significant first. + MaybeStackArray<uint8_t, 20> ubcd(precision); + for (int32_t m = 0; m < precision; m++) { + ubcd[precision - m - 1] = static_cast<uint8_t>(getDigitPos(m)); + } + output.setTo(ubcd.getAlias(), precision, scale, isNegative(), status); +} + +void DecimalQuantity::truncate() { + if (scale < 0) { + shiftRight(-scale); + scale = 0; + compact(); + } +} + +void DecimalQuantity::roundToNickel(int32_t magnitude, RoundingMode roundingMode, UErrorCode& status) { + roundToMagnitude(magnitude, roundingMode, true, status); +} + +void DecimalQuantity::roundToMagnitude(int32_t magnitude, RoundingMode roundingMode, UErrorCode& status) { + roundToMagnitude(magnitude, roundingMode, false, status); +} + +void DecimalQuantity::roundToMagnitude(int32_t magnitude, RoundingMode roundingMode, bool nickel, UErrorCode& status) { + // The position in the BCD at which rounding will be performed; digits to the right of position + // will be rounded away. + int position = safeSubtract(magnitude, scale); + + // "trailing" = least significant digit to the left of rounding + int8_t trailingDigit = getDigitPos(position); + + if (position <= 0 && !isApproximate && (!nickel || trailingDigit == 0 || trailingDigit == 5)) { + // All digits are to the left of the rounding magnitude. + } else if (precision == 0) { + // No rounding for zero. + } else { + // Perform rounding logic. + // "leading" = most significant digit to the right of rounding + int8_t leadingDigit = getDigitPos(safeSubtract(position, 1)); + + // Compute which section of the number we are in. + // EDGE means we are at the bottom or top edge, like 1.000 or 1.999 (used by doubles) + // LOWER means we are between the bottom edge and the midpoint, like 1.391 + // MIDPOINT means we are exactly in the middle, like 1.500 + // UPPER means we are between the midpoint and the top edge, like 1.916 + roundingutils::Section section; + if (!isApproximate) { + if (nickel && trailingDigit != 2 && trailingDigit != 7) { + // Nickel rounding, and not at .02x or .07x + if (trailingDigit < 2) { + // .00, .01 => down to .00 + section = roundingutils::SECTION_LOWER; + } else if (trailingDigit < 5) { + // .03, .04 => up to .05 + section = roundingutils::SECTION_UPPER; + } else if (trailingDigit < 7) { + // .05, .06 => down to .05 + section = roundingutils::SECTION_LOWER; + } else { + // .08, .09 => up to .10 + section = roundingutils::SECTION_UPPER; + } + } else if (leadingDigit < 5) { + // Includes nickel rounding .020-.024 and .070-.074 + section = roundingutils::SECTION_LOWER; + } else if (leadingDigit > 5) { + // Includes nickel rounding .026-.029 and .076-.079 + section = roundingutils::SECTION_UPPER; + } else { + // Includes nickel rounding .025 and .075 + section = roundingutils::SECTION_MIDPOINT; + for (int p = safeSubtract(position, 2); p >= 0; p--) { + if (getDigitPos(p) != 0) { + section = roundingutils::SECTION_UPPER; + break; + } + } + } + } else { + int32_t p = safeSubtract(position, 2); + int32_t minP = uprv_max(0, precision - 14); + if (leadingDigit == 0 && (!nickel || trailingDigit == 0 || trailingDigit == 5)) { + section = roundingutils::SECTION_LOWER_EDGE; + for (; p >= minP; p--) { + if (getDigitPos(p) != 0) { + section = roundingutils::SECTION_LOWER; + break; + } + } + } else if (leadingDigit == 4 && (!nickel || trailingDigit == 2 || trailingDigit == 7)) { + section = roundingutils::SECTION_MIDPOINT; + for (; p >= minP; p--) { + if (getDigitPos(p) != 9) { + section = roundingutils::SECTION_LOWER; + break; + } + } + } else if (leadingDigit == 5 && (!nickel || trailingDigit == 2 || trailingDigit == 7)) { + section = roundingutils::SECTION_MIDPOINT; + for (; p >= minP; p--) { + if (getDigitPos(p) != 0) { + section = roundingutils::SECTION_UPPER; + break; + } + } + } else if (leadingDigit == 9 && (!nickel || trailingDigit == 4 || trailingDigit == 9)) { + section = roundingutils::SECTION_UPPER_EDGE; + for (; p >= minP; p--) { + if (getDigitPos(p) != 9) { + section = roundingutils::SECTION_UPPER; + break; + } + } + } else if (nickel && trailingDigit != 2 && trailingDigit != 7) { + // Nickel rounding, and not at .02x or .07x + if (trailingDigit < 2) { + // .00, .01 => down to .00 + section = roundingutils::SECTION_LOWER; + } else if (trailingDigit < 5) { + // .03, .04 => up to .05 + section = roundingutils::SECTION_UPPER; + } else if (trailingDigit < 7) { + // .05, .06 => down to .05 + section = roundingutils::SECTION_LOWER; + } else { + // .08, .09 => up to .10 + section = roundingutils::SECTION_UPPER; + } + } else if (leadingDigit < 5) { + // Includes nickel rounding .020-.024 and .070-.074 + section = roundingutils::SECTION_LOWER; + } else { + // Includes nickel rounding .026-.029 and .076-.079 + section = roundingutils::SECTION_UPPER; + } + + bool roundsAtMidpoint = roundingutils::roundsAtMidpoint(roundingMode); + if (safeSubtract(position, 1) < precision - 14 || + (roundsAtMidpoint && section == roundingutils::SECTION_MIDPOINT) || + (!roundsAtMidpoint && section < 0 /* i.e. at upper or lower edge */)) { + // Oops! This means that we have to get the exact representation of the double, + // because the zone of uncertainty is along the rounding boundary. + convertToAccurateDouble(); + roundToMagnitude(magnitude, roundingMode, nickel, status); // start over + return; + } + + // Turn off the approximate double flag, since the value is now confirmed to be exact. + isApproximate = false; + origDouble = 0.0; + origDelta = 0; + + if (position <= 0 && (!nickel || trailingDigit == 0 || trailingDigit == 5)) { + // All digits are to the left of the rounding magnitude. + return; + } + + // Good to continue rounding. + if (section == -1) { section = roundingutils::SECTION_LOWER; } + if (section == -2) { section = roundingutils::SECTION_UPPER; } + } + + // Nickel rounding "half even" goes to the nearest whole (away from the 5). + bool isEven = nickel + ? (trailingDigit < 2 || trailingDigit > 7 + || (trailingDigit == 2 && section != roundingutils::SECTION_UPPER) + || (trailingDigit == 7 && section == roundingutils::SECTION_UPPER)) + : (trailingDigit % 2) == 0; + + bool roundDown = roundingutils::getRoundingDirection(isEven, + isNegative(), + section, + roundingMode, + status); + if (U_FAILURE(status)) { + return; + } + + // Perform truncation + if (position >= precision) { + setBcdToZero(); + scale = magnitude; + } else { + shiftRight(position); + } + + if (nickel) { + if (trailingDigit < 5 && roundDown) { + setDigitPos(0, 0); + compact(); + return; + } else if (trailingDigit >= 5 && !roundDown) { + setDigitPos(0, 9); + trailingDigit = 9; + // do not return: use the bubbling logic below + } else { + setDigitPos(0, 5); + // compact not necessary: digit at position 0 is nonzero + return; + } + } + + // Bubble the result to the higher digits + if (!roundDown) { + if (trailingDigit == 9) { + int bubblePos = 0; + // Note: in the long implementation, the most digits BCD can have at this point is + // 15, so bubblePos <= 15 and getDigitPos(bubblePos) is safe. + for (; getDigitPos(bubblePos) == 9; bubblePos++) {} + shiftRight(bubblePos); // shift off the trailing 9s + } + int8_t digit0 = getDigitPos(0); + U_ASSERT(digit0 != 9); + setDigitPos(0, static_cast<int8_t>(digit0 + 1)); + precision += 1; // in case an extra digit got added + } + + compact(); + } +} + +void DecimalQuantity::roundToInfinity() { + if (isApproximate) { + convertToAccurateDouble(); + } +} + +void DecimalQuantity::appendDigit(int8_t value, int32_t leadingZeros, bool appendAsInteger) { + U_ASSERT(leadingZeros >= 0); + + // Zero requires special handling to maintain the invariant that the least-significant digit + // in the BCD is nonzero. + if (value == 0) { + if (appendAsInteger && precision != 0) { + scale += leadingZeros + 1; + } + return; + } + + // Deal with trailing zeros + if (scale > 0) { + leadingZeros += scale; + if (appendAsInteger) { + scale = 0; + } + } + + // Append digit + shiftLeft(leadingZeros + 1); + setDigitPos(0, value); + + // Fix scale if in integer mode + if (appendAsInteger) { + scale += leadingZeros + 1; + } +} + +UnicodeString DecimalQuantity::toPlainString() const { + U_ASSERT(!isApproximate); + UnicodeString sb; + if (isNegative()) { + sb.append(u'-'); + } + if (precision == 0) { + sb.append(u'0'); + return sb; + } + int32_t upper = scale + precision + exponent - 1; + int32_t lower = scale + exponent; + if (upper < lReqPos - 1) { + upper = lReqPos - 1; + } + if (lower > rReqPos) { + lower = rReqPos; + } + int32_t p = upper; + if (p < 0) { + sb.append(u'0'); + } + for (; p >= 0; p--) { + sb.append(u'0' + getDigitPos(p - scale - exponent)); + } + if (lower < 0) { + sb.append(u'.'); + } + for(; p >= lower; p--) { + sb.append(u'0' + getDigitPos(p - scale - exponent)); + } + return sb; +} + +UnicodeString DecimalQuantity::toScientificString() const { + U_ASSERT(!isApproximate); + UnicodeString result; + if (isNegative()) { + result.append(u'-'); + } + if (precision == 0) { + result.append(u"0E+0", -1); + return result; + } + int32_t upperPos = precision - 1; + int32_t lowerPos = 0; + int32_t p = upperPos; + result.append(u'0' + getDigitPos(p)); + if ((--p) >= lowerPos) { + result.append(u'.'); + for (; p >= lowerPos; p--) { + result.append(u'0' + getDigitPos(p)); + } + } + result.append(u'E'); + int32_t _scale = upperPos + scale + exponent; + if (_scale == INT32_MIN) { + result.append({u"-2147483648", -1}); + return result; + } else if (_scale < 0) { + _scale *= -1; + result.append(u'-'); + } else { + result.append(u'+'); + } + if (_scale == 0) { + result.append(u'0'); + } + int32_t insertIndex = result.length(); + while (_scale > 0) { + std::div_t res = std::div(_scale, 10); + result.insert(insertIndex, u'0' + res.rem); + _scale = res.quot; + } + return result; +} + +//////////////////////////////////////////////////// +/// End of DecimalQuantity_AbstractBCD.java /// +/// Start of DecimalQuantity_DualStorageBCD.java /// +//////////////////////////////////////////////////// + +int8_t DecimalQuantity::getDigitPos(int32_t position) const { + if (usingBytes) { + if (position < 0 || position >= precision) { return 0; } + return fBCD.bcdBytes.ptr[position]; + } else { + if (position < 0 || position >= 16) { return 0; } + return (int8_t) ((fBCD.bcdLong >> (position * 4)) & 0xf); + } +} + +void DecimalQuantity::setDigitPos(int32_t position, int8_t value) { + U_ASSERT(position >= 0); + if (usingBytes) { + ensureCapacity(position + 1); + fBCD.bcdBytes.ptr[position] = value; + } else if (position >= 16) { + switchStorage(); + ensureCapacity(position + 1); + fBCD.bcdBytes.ptr[position] = value; + } else { + int shift = position * 4; + fBCD.bcdLong = (fBCD.bcdLong & ~(0xfL << shift)) | ((long) value << shift); + } +} + +void DecimalQuantity::shiftLeft(int32_t numDigits) { + if (!usingBytes && precision + numDigits > 16) { + switchStorage(); + } + if (usingBytes) { + ensureCapacity(precision + numDigits); + int i = precision + numDigits - 1; + for (; i >= numDigits; i--) { + fBCD.bcdBytes.ptr[i] = fBCD.bcdBytes.ptr[i - numDigits]; + } + for (; i >= 0; i--) { + fBCD.bcdBytes.ptr[i] = 0; + } + } else { + fBCD.bcdLong <<= (numDigits * 4); + } + scale -= numDigits; + precision += numDigits; +} + +void DecimalQuantity::shiftRight(int32_t numDigits) { + if (usingBytes) { + int i = 0; + for (; i < precision - numDigits; i++) { + fBCD.bcdBytes.ptr[i] = fBCD.bcdBytes.ptr[i + numDigits]; + } + for (; i < precision; i++) { + fBCD.bcdBytes.ptr[i] = 0; + } + } else { + fBCD.bcdLong >>= (numDigits * 4); + } + scale += numDigits; + precision -= numDigits; +} + +void DecimalQuantity::popFromLeft(int32_t numDigits) { + U_ASSERT(numDigits <= precision); + if (usingBytes) { + int i = precision - 1; + for (; i >= precision - numDigits; i--) { + fBCD.bcdBytes.ptr[i] = 0; + } + } else { + fBCD.bcdLong &= (static_cast<uint64_t>(1) << ((precision - numDigits) * 4)) - 1; + } + precision -= numDigits; +} + +void DecimalQuantity::setBcdToZero() { + if (usingBytes) { + uprv_free(fBCD.bcdBytes.ptr); + fBCD.bcdBytes.ptr = nullptr; + usingBytes = false; + } + fBCD.bcdLong = 0L; + scale = 0; + precision = 0; + isApproximate = false; + origDouble = 0; + origDelta = 0; + exponent = 0; +} + +void DecimalQuantity::readIntToBcd(int32_t n) { + U_ASSERT(n != 0); + // ints always fit inside the long implementation. + uint64_t result = 0L; + int i = 16; + for (; n != 0; n /= 10, i--) { + result = (result >> 4) + ((static_cast<uint64_t>(n) % 10) << 60); + } + U_ASSERT(!usingBytes); + fBCD.bcdLong = result >> (i * 4); + scale = 0; + precision = 16 - i; +} + +void DecimalQuantity::readLongToBcd(int64_t n) { + U_ASSERT(n != 0); + if (n >= 10000000000000000L) { + ensureCapacity(); + int i = 0; + for (; n != 0L; n /= 10L, i++) { + fBCD.bcdBytes.ptr[i] = static_cast<int8_t>(n % 10); + } + U_ASSERT(usingBytes); + scale = 0; + precision = i; + } else { + uint64_t result = 0L; + int i = 16; + for (; n != 0L; n /= 10L, i--) { + result = (result >> 4) + ((n % 10) << 60); + } + U_ASSERT(i >= 0); + U_ASSERT(!usingBytes); + fBCD.bcdLong = result >> (i * 4); + scale = 0; + precision = 16 - i; + } +} + +void DecimalQuantity::readDecNumberToBcd(const DecNum& decnum) { + const decNumber* dn = decnum.getRawDecNumber(); + if (dn->digits > 16) { + ensureCapacity(dn->digits); + for (int32_t i = 0; i < dn->digits; i++) { + fBCD.bcdBytes.ptr[i] = dn->lsu[i]; + } + } else { + uint64_t result = 0L; + for (int32_t i = 0; i < dn->digits; i++) { + result |= static_cast<uint64_t>(dn->lsu[i]) << (4 * i); + } + fBCD.bcdLong = result; + } + scale = dn->exponent; + precision = dn->digits; +} + +void DecimalQuantity::readDoubleConversionToBcd( + const char* buffer, int32_t length, int32_t point) { + // NOTE: Despite the fact that double-conversion's API is called + // "DoubleToAscii", they actually use '0' (as opposed to u8'0'). + if (length > 16) { + ensureCapacity(length); + for (int32_t i = 0; i < length; i++) { + fBCD.bcdBytes.ptr[i] = buffer[length-i-1] - '0'; + } + } else { + uint64_t result = 0L; + for (int32_t i = 0; i < length; i++) { + result |= static_cast<uint64_t>(buffer[length-i-1] - '0') << (4 * i); + } + fBCD.bcdLong = result; + } + scale = point - length; + precision = length; +} + +void DecimalQuantity::compact() { + if (usingBytes) { + int32_t delta = 0; + for (; delta < precision && fBCD.bcdBytes.ptr[delta] == 0; delta++); + if (delta == precision) { + // Number is zero + setBcdToZero(); + return; + } else { + // Remove trailing zeros + shiftRight(delta); + } + + // Compute precision + int32_t leading = precision - 1; + for (; leading >= 0 && fBCD.bcdBytes.ptr[leading] == 0; leading--); + precision = leading + 1; + + // Switch storage mechanism if possible + if (precision <= 16) { + switchStorage(); + } + + } else { + if (fBCD.bcdLong == 0L) { + // Number is zero + setBcdToZero(); + return; + } + + // Compact the number (remove trailing zeros) + // TODO: Use a more efficient algorithm here and below. There is a logarithmic one. + int32_t delta = 0; + for (; delta < precision && getDigitPos(delta) == 0; delta++); + fBCD.bcdLong >>= delta * 4; + scale += delta; + + // Compute precision + int32_t leading = precision - 1; + for (; leading >= 0 && getDigitPos(leading) == 0; leading--); + precision = leading + 1; + } +} + +void DecimalQuantity::ensureCapacity() { + ensureCapacity(40); +} + +void DecimalQuantity::ensureCapacity(int32_t capacity) { + if (capacity == 0) { return; } + int32_t oldCapacity = usingBytes ? fBCD.bcdBytes.len : 0; + if (!usingBytes) { + // TODO: There is nothing being done to check for memory allocation failures. + // TODO: Consider indexing by nybbles instead of bytes in C++, so that we can + // make these arrays half the size. + fBCD.bcdBytes.ptr = static_cast<int8_t*>(uprv_malloc(capacity * sizeof(int8_t))); + fBCD.bcdBytes.len = capacity; + // Initialize the byte array to zeros (this is done automatically in Java) + uprv_memset(fBCD.bcdBytes.ptr, 0, capacity * sizeof(int8_t)); + } else if (oldCapacity < capacity) { + auto bcd1 = static_cast<int8_t*>(uprv_malloc(capacity * 2 * sizeof(int8_t))); + uprv_memcpy(bcd1, fBCD.bcdBytes.ptr, oldCapacity * sizeof(int8_t)); + // Initialize the rest of the byte array to zeros (this is done automatically in Java) + uprv_memset(bcd1 + oldCapacity, 0, (capacity - oldCapacity) * sizeof(int8_t)); + uprv_free(fBCD.bcdBytes.ptr); + fBCD.bcdBytes.ptr = bcd1; + fBCD.bcdBytes.len = capacity * 2; + } + usingBytes = true; +} + +void DecimalQuantity::switchStorage() { + if (usingBytes) { + // Change from bytes to long + uint64_t bcdLong = 0L; + for (int i = precision - 1; i >= 0; i--) { + bcdLong <<= 4; + bcdLong |= fBCD.bcdBytes.ptr[i]; + } + uprv_free(fBCD.bcdBytes.ptr); + fBCD.bcdBytes.ptr = nullptr; + fBCD.bcdLong = bcdLong; + usingBytes = false; + } else { + // Change from long to bytes + // Copy the long into a local variable since it will get munged when we allocate the bytes + uint64_t bcdLong = fBCD.bcdLong; + ensureCapacity(); + for (int i = 0; i < precision; i++) { + fBCD.bcdBytes.ptr[i] = static_cast<int8_t>(bcdLong & 0xf); + bcdLong >>= 4; + } + U_ASSERT(usingBytes); + } +} + +void DecimalQuantity::copyBcdFrom(const DecimalQuantity &other) { + setBcdToZero(); + if (other.usingBytes) { + ensureCapacity(other.precision); + uprv_memcpy(fBCD.bcdBytes.ptr, other.fBCD.bcdBytes.ptr, other.precision * sizeof(int8_t)); + } else { + fBCD.bcdLong = other.fBCD.bcdLong; + } +} + +void DecimalQuantity::moveBcdFrom(DecimalQuantity &other) { + setBcdToZero(); + if (other.usingBytes) { + usingBytes = true; + fBCD.bcdBytes.ptr = other.fBCD.bcdBytes.ptr; + fBCD.bcdBytes.len = other.fBCD.bcdBytes.len; + // Take ownership away from the old instance: + other.fBCD.bcdBytes.ptr = nullptr; + other.usingBytes = false; + } else { + fBCD.bcdLong = other.fBCD.bcdLong; + } +} + +const char16_t* DecimalQuantity::checkHealth() const { + if (usingBytes) { + if (precision == 0) { return u"Zero precision but we are in byte mode"; } + int32_t capacity = fBCD.bcdBytes.len; + if (precision > capacity) { return u"Precision exceeds length of byte array"; } + if (getDigitPos(precision - 1) == 0) { return u"Most significant digit is zero in byte mode"; } + if (getDigitPos(0) == 0) { return u"Least significant digit is zero in long mode"; } + for (int i = 0; i < precision; i++) { + if (getDigitPos(i) >= 10) { return u"Digit exceeding 10 in byte array"; } + if (getDigitPos(i) < 0) { return u"Digit below 0 in byte array"; } + } + for (int i = precision; i < capacity; i++) { + if (getDigitPos(i) != 0) { return u"Nonzero digits outside of range in byte array"; } + } + } else { + if (precision == 0 && fBCD.bcdLong != 0) { + return u"Value in bcdLong even though precision is zero"; + } + if (precision > 16) { return u"Precision exceeds length of long"; } + if (precision != 0 && getDigitPos(precision - 1) == 0) { + return u"Most significant digit is zero in long mode"; + } + if (precision != 0 && getDigitPos(0) == 0) { + return u"Least significant digit is zero in long mode"; + } + for (int i = 0; i < precision; i++) { + if (getDigitPos(i) >= 10) { return u"Digit exceeding 10 in long"; } + if (getDigitPos(i) < 0) { return u"Digit below 0 in long (?!)"; } + } + for (int i = precision; i < 16; i++) { + if (getDigitPos(i) != 0) { return u"Nonzero digits outside of range in long"; } + } + } + + // No error + return nullptr; +} + +bool DecimalQuantity::operator==(const DecimalQuantity& other) const { + bool basicEquals = + scale == other.scale + && precision == other.precision + && flags == other.flags + && lReqPos == other.lReqPos + && rReqPos == other.rReqPos + && isApproximate == other.isApproximate; + if (!basicEquals) { + return false; + } + + if (precision == 0) { + return true; + } else if (isApproximate) { + return origDouble == other.origDouble && origDelta == other.origDelta; + } else { + for (int m = getUpperDisplayMagnitude(); m >= getLowerDisplayMagnitude(); m--) { + if (getDigit(m) != other.getDigit(m)) { + return false; + } + } + return true; + } +} + +UnicodeString DecimalQuantity::toString() const { + MaybeStackArray<char, 30> digits(precision + 1); + for (int32_t i = 0; i < precision; i++) { + digits[i] = getDigitPos(precision - i - 1) + '0'; + } + digits[precision] = 0; // terminate buffer + char buffer8[100]; + snprintf( + buffer8, + sizeof(buffer8), + "<DecimalQuantity %d:%d %s %s%s%s%d>", + lReqPos, + rReqPos, + (usingBytes ? "bytes" : "long"), + (isNegative() ? "-" : ""), + (precision == 0 ? "0" : digits.getAlias()), + "E", + scale); + return UnicodeString(buffer8, -1, US_INV); +} + +#endif /* #if !UCONFIG_NO_FORMATTING */ |