@@ -124,6 +124,8 @@
uint32_t decNumberToUInt32(const decNumber *, decContext *);
int32_t decNumberToInt32(const decNumber *, decContext *);
int64_t decNumberIntegralToInt64(const decNumber *dn, decContext *set);
+ void decNumberIntegralToInt128(const decNumber *dn, decContext *set,
+ uint64_t *plow, uint64_t *phigh);
uint8_t * decNumberGetBCD(const decNumber *, uint8_t *);
decNumber * decNumberSetBCD(decNumber *, const uint8_t *, uint32_t);
@@ -98,7 +98,7 @@
/* Shared lookup tables */
extern const uByte DECSTICKYTAB[10]; /* re-round digits if sticky */
- extern const uLong DECPOWERS[19]; /* powers of ten table */
+ extern const uLong DECPOWERS[20]; /* powers of ten table */
/* The following are included from decDPD.h */
extern const uShort DPD2BIN[1024]; /* DPD -> 0-999 */
extern const uShort BIN2DPD[1000]; /* 0-999 -> DPD */
@@ -53,12 +53,13 @@ static const Flag *mfctop=(Flag *)&mfcone; /* -> top byte */
const uByte DECSTICKYTAB[10]={1,1,2,3,4,6,6,7,8,9}; /* used if sticky */
/* ------------------------------------------------------------------ */
-/* Powers of ten (powers[n]==10**n, 0<=n<=9) */
+/* Powers of ten (powers[n]==10**n, 0<=n<=19) */
/* ------------------------------------------------------------------ */
-const uLong DECPOWERS[19] = {1, 10, 100, 1000, 10000, 100000, 1000000,
+const uLong DECPOWERS[20] = {1, 10, 100, 1000, 10000, 100000, 1000000,
10000000, 100000000, 1000000000, 10000000000ULL, 100000000000ULL,
1000000000000ULL, 10000000000000ULL, 100000000000000ULL, 1000000000000000ULL,
- 10000000000000000ULL, 100000000000000000ULL, 1000000000000000000ULL, };
+ 10000000000000000ULL, 100000000000000000ULL, 1000000000000000000ULL,
+ 10000000000000000000ULL,};
/* ------------------------------------------------------------------ */
/* decContextClearStatus -- clear bits in current status */
@@ -264,6 +264,7 @@ static decNumber * decTrim(decNumber *, decContext *, Flag, Int *);
static Int decUnitAddSub(const Unit *, Int, const Unit *, Int, Int,
Unit *, Int);
static Int decUnitCompare(const Unit *, Int, const Unit *, Int, Int);
+static bool mulUInt128ByPowOf10(uLong *, uLong *, uInt);
#if !DECSUBSET
/* decFinish == decFinalize when no subset arithmetic needed */
@@ -542,6 +543,68 @@ Invalid:
return 0;
} /* decNumberIntegralToInt64 */
+/* ------------------------------------------------------------------ */
+/* decNumberIntegralToInt128 -- conversion to int128 */
+/* */
+/* dn is the decNumber to convert. dn is assumed to have been */
+/* rounded to a floating point integer value. */
+/* set is the context for reporting errors */
+/* returns the converted decNumber via plow and phigh */
+/* */
+/* Invalid is set if the decNumber is a NaN, Infinite or is out of */
+/* range for a signed 128 bit integer. */
+/* ------------------------------------------------------------------ */
+
+void decNumberIntegralToInt128(const decNumber *dn, decContext *set,
+ uint64_t *plow, uint64_t *phigh)
+{
+ int d; /* work */
+ const Unit *up; /* .. */
+ uint64_t lo = 0, hi = 0;
+
+ if (decNumberIsSpecial(dn) || (dn->exponent < 0) ||
+ (dn->digits + dn->exponent > 39)) {
+ goto Invalid;
+ }
+
+ up = dn->lsu; /* -> lsu */
+
+ for (d = (dn->digits - 1) / DECDPUN; d >= 0; d--) {
+ if (mulu128(&lo, &hi, DECDPUNMAX + 1)) {
+ /* overflow */
+ goto Invalid;
+ }
+ if (uadd64_overflow(lo, up[d], &lo)) {
+ if (uadd64_overflow(hi, 1, &hi)) {
+ /* overflow */
+ goto Invalid;
+ }
+ }
+ }
+
+ if (mulUInt128ByPowOf10(&lo, &hi, dn->exponent)) {
+ /* overflow */
+ goto Invalid;
+ }
+
+ if (decNumberIsNegative(dn)) {
+ if (lo == 0) {
+ *phigh = -hi;
+ *plow = 0;
+ } else {
+ *phigh = ~hi;
+ *plow = -lo;
+ }
+ } else {
+ *plow = lo;
+ *phigh = hi;
+ }
+
+ return;
+
+Invalid:
+ decContextSetStatus(set, DEC_Invalid_operation);
+} /* decNumberIntegralToInt128 */
/* ------------------------------------------------------------------ */
/* to-scientific-string -- conversion to numeric string */
@@ -7885,6 +7948,38 @@ static Int decGetDigits(Unit *uar, Int len) {
return digits;
} /* decGetDigits */
+/* ------------------------------------------------------------------ */
+/* mulUInt128ByPowOf10 -- multiply a 128-bit unsigned integer by a */
+/* power of 10. */
+/* */
+/* The 128-bit factor composed of plow and phigh is multiplied */
+/* by 10^exp. */
+/* */
+/* plow pointer to the low 64 bits of the first factor */
+/* phigh pointer to the high 64 bits of the first factor */
+/* exp the exponent of the power of 10 of the second factor */
+/* */
+/* If the result fits in 128 bits, returns false and the */
+/* multiplication result through plow and phigh. */
+/* Otherwise, returns true. */
+/* ------------------------------------------------------------------ */
+static bool mulUInt128ByPowOf10(uLong *plow, uLong *phigh, uInt pow10)
+{
+ while (pow10 >= ARRAY_SIZE(powers)) {
+ if (mulu128(plow, phigh, powers[ARRAY_SIZE(powers) - 1])) {
+ /* Overflow */
+ return true;
+ }
+ pow10 -= ARRAY_SIZE(powers) - 1;
+ }
+
+ if (pow10 > 0) {
+ return mulu128(plow, phigh, powers[pow10]);
+ } else {
+ return false;
+ }
+}
+
#if DECTRACE | DECCHECK
/* ------------------------------------------------------------------ */
/* decNumberShow -- display a number [debug aid] */