Mirrors/Ryujinx
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Arm64: Simplify TryEncodeBitMask and use for constants (#4328)

Browse source 
* Arm64: Simplify TryEncodeBitMask

* CodeGenerator: Use TryEncodeBitMask in GenerateConstantCopy

* Ptc: Bump version
This commit is contained in:
merry 2023-01-22 14:15:49 +00:00 committed by GitHub
parent 32a1cd83fd
commit 4f293f8cbe
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
5 changed files with 81 additions and 107 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

6
ARMeilleure/ARMeilleure.csproj
View file

@ -16,4 +16,10 @@
</ContentWithTargetPath>
</ItemGroup>
<ItemGroup>
<AssemblyAttribute Include="System.Runtime.CompilerServices.InternalsVisibleTo">
<_Parameter1>Ryujinx.Tests</_Parameter1>
</AssemblyAttribute>
</ItemGroup>
</Project>

120
ARMeilleure/CodeGen/Arm64/CodeGenCommon.cs
View file

@ -1,5 +1,4 @@
using ARMeilleure.IntermediateRepresentation;
using System;
using System.Numerics;
namespace ARMeilleure.CodeGen.Arm64
@ -32,9 +31,12 @@ namespace ARMeilleure.CodeGen.Arm64
public static bool TryEncodeBitMask(Operand operand, out int immN, out int immS, out int immR)
{
ulong value = operand.Value;
return TryEncodeBitMask(operand.Type, operand.Value, out immN, out immS, out immR);
}
if (operand.Type == OperandType.I32)
public static bool TryEncodeBitMask(OperandType type, ulong value, out int immN, out int immS, out int immR)
{
if (type == OperandType.I32)
{
value |= value << 32;
}
@ -50,7 +52,7 @@ namespace ARMeilleure.CodeGen.Arm64
// Any value AND all ones will be equal itself, so it's effectively a no-op.
// Any value OR all ones will be equal all ones, so one can just use MOV.
// Any value XOR all ones will be equal its inverse, so one can just use MVN.
if (value == ulong.MaxValue)
if (value == 0 || value == ulong.MaxValue)
{
immN = 0;
immS = 0;
@ -59,79 +61,18 @@ namespace ARMeilleure.CodeGen.Arm64
return false;
}
int bitLength = CountSequence(value);
// Normalize value, rotating it such that the LSB is 1: Ensures we get a complete element that has not
// been cut-in-half across the word boundary.
int rotation = BitOperations.TrailingZeroCount(value & (value + 1));
ulong rotatedValue = ulong.RotateRight(value, rotation);
if ((value >> bitLength) != 0)
{
bitLength += CountSequence(value >> bitLength);
}
// Now that we have a complete element in the LSB with the LSB = 1, determine size and number of ones
// in element.
int elementSize = BitOperations.TrailingZeroCount(rotatedValue & (rotatedValue + 1));
int onesInElement = BitOperations.TrailingZeroCount(~rotatedValue);
int bitLengthLog2 = BitOperations.Log2((uint)bitLength);
int bitLengthPow2 = 1 << bitLengthLog2;
if (bitLengthPow2 < bitLength)
{
bitLengthLog2++;
bitLengthPow2 <<= 1;
}
int selectedESize = 64;
int repetitions = 1;
int onesCount = BitOperations.PopCount(value);
if (bitLengthPow2 < 64 && (value >> bitLengthPow2) != 0)
{
for (int eSizeLog2 = bitLengthLog2; eSizeLog2 < 6; eSizeLog2++)
{
bool match = true;
int eSize = 1 << eSizeLog2;
ulong mask = (1UL << eSize) - 1;
ulong eValue = value & mask;
for (int e = 1; e < 64 / eSize; e++)
{
if (((value >> (e * eSize)) & mask) != eValue)
{
match = false;
break;
}
}
if (match)
{
selectedESize = eSize;
repetitions = 64 / eSize;
onesCount = BitOperations.PopCount(eValue);
break;
}
}
}
// Find rotation. We have two cases, one where the highest bit is 0
// and one where it is 1.
// If it's 1, we just need to count the number of 1 bits on the MSB to find the right rotation.
// If it's 0, we just need to count the number of 0 bits on the LSB to find the left rotation,
// then we can convert it to the right rotation shift by subtracting the value from the element size.
int rotation;
long vHigh = (long)(value << (64 - selectedESize));
if (vHigh < 0)
{
rotation = BitOperations.LeadingZeroCount(~(ulong)vHigh);
}
else
{
rotation = (selectedESize - BitOperations.TrailingZeroCount(value)) & (selectedESize - 1);
}
// Reconstruct value and see if it matches. If not, we can't encode.
ulong reconstructed = onesCount == 64 ? ulong.MaxValue : RotateRight((1UL << onesCount) - 1, rotation, selectedESize);
for (int bit = 32; bit >= selectedESize; bit >>= 1)
{
reconstructed |= reconstructed << bit;
}
if (reconstructed != value || onesCount == 0)
// Check the value is repeating; also ensures element size is a power of two.
if (ulong.RotateRight(value, elementSize) != value)
{
immN = 0;
immS = 0;
@ -140,34 +81,11 @@ namespace ARMeilleure.CodeGen.Arm64
return false;
}
immR = rotation;
// immN indicates that there are no repetitions.
// The MSB of immS indicates the amount of repetitions, and the LSB the number of bits set.
if (repetitions == 1)
{
immN = 1;
immS = 0;
}
else
{
immN = 0;
immS = (0xf80 >> BitOperations.Log2((uint)repetitions)) & 0x3f;
}
immS |= onesCount - 1;
immN = (elementSize >> 6) & 1;
immS = (((~elementSize + 1) << 1) | (onesInElement - 1)) & 0x3f;
immR = (elementSize - rotation) & (elementSize - 1);
return true;
}
private static int CountSequence(ulong value)
{
return BitOperations.TrailingZeroCount(value) + BitOperations.TrailingZeroCount(~value);
}
private static ulong RotateRight(ulong bits, int shift, int size)
{
return (bits >> shift) | ((bits << (size - shift)) & (size == 64 ? ulong.MaxValue : (1UL << size) - 1));
}
}
}

14
ARMeilleure/CodeGen/Arm64/CodeGenerator.cs
View file

@ -1303,7 +1303,15 @@ namespace ARMeilleure.CodeGen.Arm64
private static void GenerateConstantCopy(CodeGenContext context, Operand dest, ulong value)
{
if (value != 0)
if (value == 0)
{
context.Assembler.Mov(dest, Register(ZrRegister, dest.Type));
}
else if (CodeGenCommon.TryEncodeBitMask(dest.Type, value, out _, out _, out _))
{
context.Assembler.Orr(dest, Register(ZrRegister, dest.Type), Const(dest.Type, (long)value));
}
else
{
int hw = 0;
bool first = true;
@ -1328,10 +1336,6 @@ namespace ARMeilleure.CodeGen.Arm64
value >>= 16;
}
}
else
{
context.Assembler.Mov(dest, Register(ZrRegister, dest.Type));
}
}
private static void GenerateAtomicCas(

2
ARMeilleure/Translation/PTC/Ptc.cs
View file

@ -29,7 +29,7 @@ namespace ARMeilleure.Translation.PTC
private const string OuterHeaderMagicString = "PTCohd\0\0";
private const string InnerHeaderMagicString = "PTCihd\0\0";
private const uint InternalVersion = 4272; //! To be incremented manually for each change to the ARMeilleure project.
private const uint InternalVersion = 4328; //! To be incremented manually for each change to the ARMeilleure project.
private const string ActualDir = "0";
private const string BackupDir = "1";

46
Ryujinx.Tests/Cpu/Arm64CodeGenCommonTests.cs Normal file
View file

@ -0,0 +1,46 @@
using ARMeilleure.CodeGen.Arm64;
using NUnit.Framework;
namespace Ryujinx.Tests.Cpu
{
public class Arm64CodeGenCommonTests
{
public struct TestCase
{
public ulong Value;
public bool Valid;
public int ImmN;
public int ImmS;
public int ImmR;
}
public static readonly TestCase[] TestCases =
{
new() { Value = 0, Valid = false, ImmN = 0, ImmS = 0, ImmR = 0 },
new() { Value = 0x970977f35f848714, Valid = false, ImmN = 0, ImmS = 0, ImmR = 0 },
new() { Value = 0xffffffffffffffff, Valid = false, ImmN = 0, ImmS = 0, ImmR = 0 },
new() { Value = 0x5555555555555555, Valid = true, ImmN = 0, ImmS = 0x3c, ImmR = 0 },
new() { Value = 0xaaaaaaaaaaaaaaaa, Valid = true, ImmN = 0, ImmS = 0x3c, ImmR = 1 },
new() { Value = 0x6666666666666666, Valid = true, ImmN = 0, ImmS = 0x39, ImmR = 3 },
new() { Value = 0x1c1c1c1c1c1c1c1c, Valid = true, ImmN = 0, ImmS = 0x32, ImmR = 6 },
new() { Value = 0x0f0f0f0f0f0f0f0f, Valid = true, ImmN = 0, ImmS = 0x33, ImmR = 0 },
new() { Value = 0xf1f1f1f1f1f1f1f1, Valid = true, ImmN = 0, ImmS = 0x34, ImmR = 4 },
new() { Value = 0xe7e7e7e7e7e7e7e7, Valid = true, ImmN = 0, ImmS = 0x35, ImmR = 3 },
new() { Value = 0xc001c001c001c001, Valid = true, ImmN = 0, ImmS = 0x22, ImmR = 2 },
new() { Value = 0x0000038000000380, Valid = true, ImmN = 0, ImmS = 0x02, ImmR = 25 },
new() { Value = 0xffff8fffffff8fff, Valid = true, ImmN = 0, ImmS = 0x1c, ImmR = 17 },
new() { Value = 0x000000000ffff800, Valid = true, ImmN = 1, ImmS = 0x10, ImmR = 53 },
};
[Test]
public void BitImmTests([ValueSource(nameof(TestCases))] TestCase test)
{
bool valid = CodeGenCommon.TryEncodeBitMask(test.Value, out int immN, out int immS, out int immR);
Assert.That(valid, Is.EqualTo(test.Valid));
Assert.That(immN, Is.EqualTo(test.ImmN));
Assert.That(immS, Is.EqualTo(test.ImmS));
Assert.That(immR, Is.EqualTo(test.ImmR));
}
}
}