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Extend the small inverse pow5 offset table #237

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Extend the small inverse pow5 offset table #237

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5 changes: 3 additions & 2 deletions ryu/d2s_small_table.h
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Original file line number Diff line number Diff line change
Expand Up @@ -41,11 +41,11 @@ static const uint64_t DOUBLE_POW5_INV_SPLIT2[15][2] = {
{ 10313493231639821582u, 1313665730009899186u },
{ 12701016819766672773u, 2032799256770390445u }
};
static const uint32_t POW5_INV_OFFSETS[19] = {
static const uint32_t POW5_INV_OFFSETS[22] = {
0x54544554, 0x04055545, 0x10041000, 0x00400414, 0x40010000, 0x41155555,
0x00000454, 0x00010044, 0x40000000, 0x44000041, 0x50454450, 0x55550054,
0x51655554, 0x40004000, 0x01000001, 0x00010500, 0x51515411, 0x05555554,
0x00000000
0x50411500, 0x40040000, 0x05040110, 0x00000000,
};

static const uint64_t DOUBLE_POW5_SPLIT2[13][2] = {
Expand Down Expand Up @@ -173,6 +173,7 @@ static inline void double_computeInvPow5(const uint32_t i, uint64_t* const resul
}
// high1 | sum | low0
const uint32_t delta = pow5bits(base2) - pow5bits(i);
assert (i/16 < sizeof(POW5_INV_OFFSETS) / sizeof(POW5_INV_OFFSETS[0]));
result[0] = shiftright128(low0, sum, delta) + 1 + ((POW5_INV_OFFSETS[i / 16] >> ((i % 16) << 1)) & 3);
result[1] = shiftright128(sum, high1, delta);
}
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