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PrimeOrderCalculatorAccelerator.Rent is now created outside of the loops and re-used for all calculations.

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mlemanczyk committed 2025-11-24 22:51:53 +01:00
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commit b9ca95bf8c
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+4639 -4229
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PerfectNumbers.Core/Cpu/MersenneNumberIncrementalCpuTester.cs
+80 -78
View File
@@ -1,90 +1,92 @@
using PerfectNumbers.Core.Gpu.Accelerators;
namespace PerfectNumbers.Core.Cpu;
public class MersenneNumberIncrementalCpuTester(GpuKernelType kernelType)
{
private static readonly MersenneDivisorCycles _cycles = MersenneDivisorCycles.Shared;
private readonly GpuKernelType _kernelType = kernelType;
private static readonly MersenneDivisorCycles _cycles = MersenneDivisorCycles.Shared;
private readonly GpuKernelType _kernelType = kernelType;
public void Scan(ulong exponent, UInt128 twoP, LastDigit lastDigit, UInt128 maxK, ref bool isPrime)
{
UInt128 k = UInt128.One;
UInt128 one = k;
ulong divMul = (ulong)((((UInt128)1 << 64) - UInt128.One) / exponent) + 1UL;
// Use residue automaton always on CPU
var auto = new MersenneResidueAutomaton(exponent);
public void Scan(PrimeOrderCalculatorAccelerator gpu, ulong exponent, UInt128 twoP, LastDigit lastDigit, UInt128 maxK, ref bool isPrime)
{
UInt128 k = UInt128.One;
UInt128 one = k;
ulong divMul = (ulong)((((UInt128)1 << 64) - UInt128.One) / exponent) + 1UL;
// Use residue automaton always on CPU
var auto = new MersenneResidueAutomaton(exponent);
bool reject;
bool shouldCheck;
UInt128 q = auto.CurrentQ();
UInt128 divPow;
UInt128 halfPow;
UInt128 phi;
UInt128 qCycle;
bool reject;
bool shouldCheck;
UInt128 q = auto.CurrentQ();
UInt128 divPow;
UInt128 halfPow;
UInt128 phi;
UInt128 qCycle;
ulong div;
ulong mod8;
ulong phi64;
ulong div;
ulong mod8;
ulong phi64;
while (k <= maxK && Volatile.Read(ref isPrime))
{
// TODO: Replace this direct GetCycle call with DivisorCycleCache.Lookup so we reuse the single snapshot block
// and compute missing cycles on the configured device without queuing additional block generation.
qCycle = MersenneDivisorCycles.GetCycle(q);
shouldCheck = auto.Mod10R != 5UL;
if (shouldCheck)
{
mod8 = auto.Mod8R;
if (mod8 != 1UL && mod8 != 7UL)
{
shouldCheck = false;
}
else if (auto.Mod3R == 0UL || auto.Mod5R == 0UL)
{
// TODO: Swap these Mod3/Mod5 zero checks to the cached residue tables once the automaton exposes
// the benchmarked lookup-based helpers so CPU scans avoid runtime modulo instructions.
shouldCheck = false;
}
}
while (k <= maxK && Volatile.Read(ref isPrime))
{
// TODO: Replace this direct GetCycle call with DivisorCycleCache.Lookup so we reuse the single snapshot block
// and compute missing cycles on the configured device without queuing additional block generation.
qCycle = MersenneDivisorCycles.GetCycle(gpu, q);
shouldCheck = auto.Mod10R != 5UL;
if (shouldCheck)
{
mod8 = auto.Mod8R;
if (mod8 != 1UL && mod8 != 7UL)
{
shouldCheck = false;
}
else if (auto.Mod3R == 0UL || auto.Mod5R == 0UL)
{
// TODO: Swap these Mod3/Mod5 zero checks to the cached residue tables once the automaton exposes
// the benchmarked lookup-based helpers so CPU scans avoid runtime modulo instructions.
shouldCheck = false;
}
}
if (shouldCheck)
{
if (_kernelType == GpuKernelType.Pow2Mod)
{
reject = exponent.PowModWithCycle(q, qCycle) == UInt128.One;
}
else
{
phi = q - one;
reject = false;
if (phi <= ulong.MaxValue)
{
phi64 = (ulong)phi;
if (phi64.PowModWithCycle(q, qCycle) == one)
{
halfPow = (phi64 >> 1).PowModWithCycle(q, qCycle) - one;
if (halfPow.BinaryGcd(q) == one)
{
div = phi64.FastDiv64(exponent, divMul);
divPow = div.PowModWithCycle(q, qCycle) - one;
if (divPow.BinaryGcd(q) == one)
{
reject = true;
}
}
}
}
}
if (shouldCheck)
{
if (_kernelType == GpuKernelType.Pow2Mod)
{
reject = exponent.PowModWithCycle(q, qCycle) == UInt128.One;
}
else
{
phi = q - one;
reject = false;
if (phi <= ulong.MaxValue)
{
phi64 = (ulong)phi;
if (phi64.PowModWithCycle(q, qCycle) == one)
{
halfPow = (phi64 >> 1).PowModWithCycle(q, qCycle) - one;
if (halfPow.BinaryGcd(q) == one)
{
div = phi64.FastDiv64(exponent, divMul);
divPow = div.PowModWithCycle(q, qCycle) - one;
if (divPow.BinaryGcd(q) == one)
{
reject = true;
}
}
}
}
}
if (reject && q.IsPrimeCandidate())
{
Volatile.Write(ref isPrime, false);
break;
}
}
if (reject && q.IsPrimeCandidate())
{
Volatile.Write(ref isPrime, false);
break;
}
}
k += 1UL;
auto.Next();
q = auto.CurrentQ();
}
}
k += 1UL;
auto.Next();
q = auto.CurrentQ();
}
}
}