Ryujinx/Ryujinx.Tests/Cpu/Tester/Pseudocode.cs

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// https://github.com/LDj3SNuD/ARM_v8-A_AArch64_Instructions_Tester/blob/master/Tester/Pseudocode.cs
// https://meriac.github.io/archex/A64_v83A_ISA/shared_pseudocode.xml
// https://alastairreid.github.io/asl-lexical-syntax/
// | ------------------------|----------------------------------- |
// | ASL | C# |
// | ------------------------|----------------------------------- |
// | bit, bits(1); boolean | bool |
// | bits | Bits |
// | integer | BigInteger, int |
// | real | decimal |
// | ------------------------|----------------------------------- |
// | '0'; FALSE | false |
// | '1'; TRUE | true |
// | '010' | "010" |
// | bitsX IN {bitsY, bitsZ} | (bitsX == bitsY || bitsX == bitsZ) |
// | DIV | / |
// | MOD | % |
// | ------------------------|----------------------------------- |
using System;
using System.Numerics;
namespace Ryujinx.Tests.Cpu.Tester
{
using Types;
using static Shared;
internal static class AArch64
{
#region "exceptions/exceptions/"
/* #AArch64.ResetControlRegisters.1 */
public static void ResetControlRegisters(bool cold_reset)
{
PSTATE.N = cold_reset;
PSTATE.Z = cold_reset;
PSTATE.C = cold_reset;
PSTATE.V = cold_reset;
}
/* */
public static void TakeReset(bool cold_reset)
{
/* assert !HighestELUsingAArch32(); */
// Enter the highest implemented Exception level in AArch64 state
if (HaveEL(EL3))
{
PSTATE.EL = EL3;
}
else if (HaveEL(EL2))
{
PSTATE.EL = EL2;
}
else
{
PSTATE.EL = EL1;
}
// Reset the system registers and other system components
AArch64.ResetControlRegisters(cold_reset);
// Reset all other PSTATE fields
PSTATE.SP = true; // Select stack pointer
// All registers, bits and fields not reset by the above pseudocode or by the BranchTo() call
// below are UNKNOWN bitstrings after reset. In particular, the return information registers
// ELR_ELx and SPSR_ELx have UNKNOWN values, so that it
// is impossible to return from a reset in an architecturally defined way.
AArch64.ResetGeneralRegisters();
AArch64.ResetSIMDFPRegisters();
AArch64.ResetSpecialRegisters();
}
#endregion
#region "functions/registers/"
/* #AArch64.ResetGeneralRegisters.0 */
public static void ResetGeneralRegisters()
{
for (int i = 0; i <= 30; i++)
{
/* X[i] = bits(64) UNKNOWN; */
_R[i].SetAll(false);
}
}
/* #AArch64.ResetSIMDFPRegisters.0 */
public static void ResetSIMDFPRegisters()
{
for (int i = 0; i <= 31; i++)
{
/* V[i] = bits(128) UNKNOWN; */
_V[i].SetAll(false);
}
}
/* #AArch64.ResetSpecialRegisters.0 */
public static void ResetSpecialRegisters()
{
// AArch64 special registers
/* SP_EL0 = bits(64) UNKNOWN; */
SP_EL0.SetAll(false);
/* SP_EL1 = bits(64) UNKNOWN; */
SP_EL1.SetAll(false);
FPSR.SetAll(false); // FIXME: Temporary solution.
}
// #impl-aarch64.SP.write.0
public static void SP(Bits value)
{
/* int width = value.Count; */
/* assert width IN {32,64}; */
if (!PSTATE.SP)
{
SP_EL0 = ZeroExtend(64, value);
}
else
{
switch (PSTATE.EL)
{
case Bits bits when bits == EL0:
SP_EL0 = ZeroExtend(64, value);
break;
default:
case Bits bits when bits == EL1:
SP_EL1 = ZeroExtend(64, value);
break;/*
case Bits bits when bits == EL2:
SP_EL2 = ZeroExtend(64, value);
break;
case Bits bits when bits == EL3:
SP_EL3 = ZeroExtend(64, value);
break;*/
}
}
}
// #impl-aarch64.SP.read.0
public static Bits SP(int width)
{
/* assert width IN {8,16,32,64}; */
if (!PSTATE.SP)
{
return SP_EL0[width - 1, 0];
}
else
{
switch (PSTATE.EL)
{
case Bits bits when bits == EL0:
return SP_EL0[width - 1, 0];
default:
case Bits bits when bits == EL1:
return SP_EL1[width - 1, 0];/*
case Bits bits when bits == EL2:
return SP_EL2[width - 1, 0];
case Bits bits when bits == EL3:
return SP_EL3[width - 1, 0];*/
}
}
}
// #impl-aarch64.V.write.1
public static void V(int n, Bits value)
{
/* int width = value.Count; */
/* assert n >= 0 && n <= 31; */
/* assert width IN {8,16,32,64,128}; */
_V[n] = ZeroExtend(128, value);
}
/* #impl-aarch64.V.read.1 */
public static Bits V(int width, int n)
{
/* assert n >= 0 && n <= 31; */
/* assert width IN {8,16,32,64,128}; */
return _V[n][width - 1, 0];
}
/* #impl-aarch64.Vpart.read.2 */
public static Bits Vpart(int width, int n, int part)
{
/* assert n >= 0 && n <= 31; */
/* assert part IN {0, 1}; */
if (part == 0)
{
/* assert width IN {8,16,32,64}; */
return _V[n][width - 1, 0];
}
else
{
/* assert width == 64; */
return _V[n][(width * 2) - 1, width];
}
}
// #impl-aarch64.Vpart.write.2
public static void Vpart(int n, int part, Bits value)
{
int width = value.Count;
/* assert n >= 0 && n <= 31; */
/* assert part IN {0, 1}; */
if (part == 0)
{
/* assert width IN {8,16,32,64}; */
_V[n] = ZeroExtend(128, value);
}
else
{
/* assert width == 64; */
_V[n][(width * 2) - 1, width] = value[width - 1, 0];
}
}
// #impl-aarch64.X.write.1
public static void X(int n, Bits value)
{
/* int width = value.Count; */
/* assert n >= 0 && n <= 31; */
/* assert width IN {32,64}; */
if (n != 31)
{
_R[n] = ZeroExtend(64, value);
}
}
/* #impl-aarch64.X.read.1 */
public static Bits X(int width, int n)
{
/* assert n >= 0 && n <= 31; */
/* assert width IN {8,16,32,64}; */
if (n != 31)
{
return _R[n][width - 1, 0];
}
else
{
return Zeros(width);
}
}
#endregion
#region "instrs/countop/"
// #CountOp
public enum CountOp {CountOp_CLZ, CountOp_CLS, CountOp_CNT};
#endregion
#region "instrs/extendreg/"
/* #impl-aarch64.DecodeRegExtend.1 */
public static ExtendType DecodeRegExtend(Bits op)
{
switch (op)
{
default:
case Bits bits when bits == "000":
return ExtendType.ExtendType_UXTB;
case Bits bits when bits == "001":
return ExtendType.ExtendType_UXTH;
case Bits bits when bits == "010":
return ExtendType.ExtendType_UXTW;
case Bits bits when bits == "011":
return ExtendType.ExtendType_UXTX;
case Bits bits when bits == "100":
return ExtendType.ExtendType_SXTB;
case Bits bits when bits == "101":
return ExtendType.ExtendType_SXTH;
case Bits bits when bits == "110":
return ExtendType.ExtendType_SXTW;
case Bits bits when bits == "111":
return ExtendType.ExtendType_SXTX;
}
}
/* #impl-aarch64.ExtendReg.3 */
public static Bits ExtendReg(int N, int reg, ExtendType type, int shift)
{
/* assert shift >= 0 && shift <= 4; */
Bits val = X(N, reg);
bool unsigned;
int len;
switch (type)
{
default:
case ExtendType.ExtendType_SXTB:
unsigned = false; len = 8;
break;
case ExtendType.ExtendType_SXTH:
unsigned = false; len = 16;
break;
case ExtendType.ExtendType_SXTW:
unsigned = false; len = 32;
break;
case ExtendType.ExtendType_SXTX:
unsigned = false; len = 64;
break;
case ExtendType.ExtendType_UXTB:
unsigned = true; len = 8;
break;
case ExtendType.ExtendType_UXTH:
unsigned = true; len = 16;
break;
case ExtendType.ExtendType_UXTW:
unsigned = true; len = 32;
break;
case ExtendType.ExtendType_UXTX:
unsigned = true; len = 64;
break;
}
// Note the extended width of the intermediate value and
// that sign extension occurs from bit <len+shift-1>, not
// from bit <len-1>. This is equivalent to the instruction
// [SU]BFIZ Rtmp, Rreg, #shift, #len
// It may also be seen as a sign/zero extend followed by a shift:
// LSL(Extend(val<len-1:0>, N, unsigned), shift);
len = Min(len, N - shift);
return Extend(Bits.Concat(val[len - 1, 0], Zeros(shift)), N, unsigned);
}
// #ExtendType
public enum ExtendType {ExtendType_SXTB, ExtendType_SXTH, ExtendType_SXTW, ExtendType_SXTX,
ExtendType_UXTB, ExtendType_UXTH, ExtendType_UXTW, ExtendType_UXTX};
#endregion
#region "instrs/integer/bitmasks/"
/* #impl-aarch64.DecodeBitMasks.4 */
public static (Bits, Bits) DecodeBitMasks(int M, bool immN, Bits imms, Bits immr, bool immediate)
{
Bits tmask, wmask;
Bits tmask_and, wmask_and;
Bits tmask_or, wmask_or;
Bits levels;
// Compute log2 of element size
// 2^len must be in range [2, M]
int len = HighestSetBit(Bits.Concat(immN, NOT(imms)));
/* if len < 1 then ReservedValue(); */
/* assert M >= (1 << len); */
// Determine S, R and S - R parameters
levels = ZeroExtend(Ones(len), 6);
// For logical immediates an all-ones value of S is reserved
// since it would generate a useless all-ones result (many times)
/* if immediate && (imms AND levels) == levels then ReservedValue(); */
BigInteger S = UInt(AND(imms, levels));
BigInteger R = UInt(AND(immr, levels));
BigInteger diff = S - R; // 6-bit subtract with borrow
// Compute "top mask"
tmask_and = OR(diff.SubBigInteger(5, 0), NOT(levels));
tmask_or = AND(diff.SubBigInteger(5, 0), levels);
tmask = Ones(64);
tmask = OR(AND(tmask, Replicate(Bits.Concat(Replicate(tmask_and[0], 1), Ones( 1)), 32)), Replicate(Bits.Concat(Zeros( 1), Replicate(tmask_or[0], 1)), 32));
tmask = OR(AND(tmask, Replicate(Bits.Concat(Replicate(tmask_and[1], 2), Ones( 2)), 16)), Replicate(Bits.Concat(Zeros( 2), Replicate(tmask_or[1], 2)), 16));
tmask = OR(AND(tmask, Replicate(Bits.Concat(Replicate(tmask_and[2], 4), Ones( 4)), 8)), Replicate(Bits.Concat(Zeros( 4), Replicate(tmask_or[2], 4)), 8));
tmask = OR(AND(tmask, Replicate(Bits.Concat(Replicate(tmask_and[3], 8), Ones( 8)), 4)), Replicate(Bits.Concat(Zeros( 8), Replicate(tmask_or[3], 8)), 4));
tmask = OR(AND(tmask, Replicate(Bits.Concat(Replicate(tmask_and[4], 16), Ones(16)), 2)), Replicate(Bits.Concat(Zeros(16), Replicate(tmask_or[4], 16)), 2));
tmask = OR(AND(tmask, Replicate(Bits.Concat(Replicate(tmask_and[5], 32), Ones(32)), 1)), Replicate(Bits.Concat(Zeros(32), Replicate(tmask_or[5], 32)), 1));
// Compute "wraparound mask"
wmask_and = OR(immr, NOT(levels));
wmask_or = AND(immr, levels);
wmask = Zeros(64);
wmask = OR(AND(wmask, Replicate(Bits.Concat(Ones( 1), Replicate(wmask_and[0], 1)), 32)), Replicate(Bits.Concat(Replicate(wmask_or[0], 1), Zeros( 1)), 32));
wmask = OR(AND(wmask, Replicate(Bits.Concat(Ones( 2), Replicate(wmask_and[1], 2)), 16)), Replicate(Bits.Concat(Replicate(wmask_or[1], 2), Zeros( 2)), 16));
wmask = OR(AND(wmask, Replicate(Bits.Concat(Ones( 4), Replicate(wmask_and[2], 4)), 8)), Replicate(Bits.Concat(Replicate(wmask_or[2], 4), Zeros( 4)), 8));
wmask = OR(AND(wmask, Replicate(Bits.Concat(Ones( 8), Replicate(wmask_and[3], 8)), 4)), Replicate(Bits.Concat(Replicate(wmask_or[3], 8), Zeros( 8)), 4));
wmask = OR(AND(wmask, Replicate(Bits.Concat(Ones(16), Replicate(wmask_and[4], 16)), 2)), Replicate(Bits.Concat(Replicate(wmask_or[4], 16), Zeros(16)), 2));
wmask = OR(AND(wmask, Replicate(Bits.Concat(Ones(32), Replicate(wmask_and[5], 32)), 1)), Replicate(Bits.Concat(Replicate(wmask_or[5], 32), Zeros(32)), 1));
if (diff.SubBigInteger(6)) // borrow from S - R
{
wmask = AND(wmask, tmask);
}
else
{
wmask = OR(wmask, tmask);
}
return (wmask[M - 1, 0], tmask[M - 1, 0]);
}
#endregion
#region "instrs/integer/shiftreg/"
/* #impl-aarch64.DecodeShift.1 */
public static ShiftType DecodeShift(Bits op)
{
switch (op)
{
default:
case Bits bits when bits == "00":
return ShiftType.ShiftType_LSL;
case Bits bits when bits == "01":
return ShiftType.ShiftType_LSR;
case Bits bits when bits == "10":
return ShiftType.ShiftType_ASR;
case Bits bits when bits == "11":
return ShiftType.ShiftType_ROR;
}
}
/* #impl-aarch64.ShiftReg.3 */
public static Bits ShiftReg(int N, int reg, ShiftType type, int amount)
{
Bits result = X(N, reg);
switch (type)
{
default:
case ShiftType.ShiftType_LSL:
result = LSL(result, amount);
break;
case ShiftType.ShiftType_LSR:
result = LSR(result, amount);
break;
case ShiftType.ShiftType_ASR:
result = ASR(result, amount);
break;
case ShiftType.ShiftType_ROR:
result = ROR(result, amount);
break;
}
return result;
}
// #ShiftType
public enum ShiftType {ShiftType_LSL, ShiftType_LSR, ShiftType_ASR, ShiftType_ROR};
#endregion
#region "instrs/vector/reduce/reduceop/"
public static Bits Reduce(ReduceOp op, Bits input, int esize)
{
int N = input.Count;
int half;
Bits hi;
Bits lo;
Bits result = new Bits(esize);
if (N == esize)
{
return new Bits(input);
}
half = N / 2;
hi = Reduce(op, input[N - 1, half], esize);
lo = Reduce(op, input[half - 1, 0], esize);
switch (op)
{
case ReduceOp.ReduceOp_FMINNUM:
/* result = FPMinNum(lo, hi, FPCR); */
break;
case ReduceOp.ReduceOp_FMAXNUM:
/* result = FPMaxNum(lo, hi, FPCR); */
break;
case ReduceOp.ReduceOp_FMIN:
/* result = FPMin(lo, hi, FPCR); */
break;
case ReduceOp.ReduceOp_FMAX:
/* result = FPMax(lo, hi, FPCR); */
break;
case ReduceOp.ReduceOp_FADD:
/* result = FPAdd(lo, hi, FPCR); */
break;
default:
case ReduceOp.ReduceOp_ADD:
result = lo + hi;
break;
}
return result;
}
public enum ReduceOp {ReduceOp_FMINNUM, ReduceOp_FMAXNUM,
ReduceOp_FMIN, ReduceOp_FMAX,
ReduceOp_FADD, ReduceOp_ADD};
#endregion
}
internal static class Shared
{
static Shared()
{
_R = new Bits[31];
for (int i = 0; i <= 30; i++)
{
_R[i] = new Bits(64, false);
}
_V = new Bits[32];
for (int i = 0; i <= 31; i++)
{
_V[i] = new Bits(128, false);
}
SP_EL0 = new Bits(64, false);
SP_EL1 = new Bits(64, false);
FPSR = new Bits(32, false); // FIXME: Temporary solution.
PSTATE.N = false;
PSTATE.Z = false;
PSTATE.C = false;
PSTATE.V = false;
PSTATE.EL = EL1;
PSTATE.SP = true;
}
#region "functions/common/"
/* */
public static Bits AND(Bits x, Bits y)
{
return x.And(y);
}
// #impl-shared.ASR.2
public static Bits ASR(Bits x, int shift)
{
int N = x.Count;
/* assert shift >= 0; */
Bits result;
if (shift == 0)
{
result = new Bits(x);
}
else
{
(result, _) = ASR_C(x, shift);
}
return result;
}
// #impl-shared.ASR_C.2
public static (Bits, bool) ASR_C(Bits x, int shift)
{
int N = x.Count;
/* assert shift > 0; */
Bits extended_x = SignExtend(x, shift + N);
Bits result = extended_x[shift + N - 1, shift];
bool carry_out = extended_x[shift - 1];
return (result, carry_out);
}
// #impl-shared.Abs.1
public static BigInteger Abs(BigInteger x)
{
return (x >= 0 ? x : -x);
}
// #impl-shared.CountLeadingSignBits.1
public static int CountLeadingSignBits(Bits x)
{
int N = x.Count;
return CountLeadingZeroBits(EOR(x[N - 1, 1], x[N - 2, 0]));
}
// #impl-shared.CountLeadingZeroBits.1
public static int CountLeadingZeroBits(Bits x)
{
int N = x.Count;
return (N - 1 - HighestSetBit(x));
}
// #impl-shared.Elem.read.3
public static Bits Elem(/*in */Bits vector, int e, int size)
{
/* int N = vector.Count; */
/* assert e >= 0 && (e+1)*size <= N; */
return vector[e * size + size - 1, e * size];
}
// #impl-shared.Elem.write.3
public static void Elem(/*out */Bits vector, int e, int size, Bits value)
{
/* int N = vector.Count; */
/* assert e >= 0 && (e+1)*size <= N; */
vector[(e + 1) * size - 1, e * size] = value;
}
/* */
public static Bits EOR(Bits x, Bits y)
{
return x.Xor(y);
}
// #impl-shared.Extend.3
public static Bits Extend(Bits x, int N, bool unsigned)
{
if (unsigned)
{
return ZeroExtend(x, N);
}
else
{
return SignExtend(x, N);
}
}
/* #impl-shared.Extend.2 */
public static Bits Extend(int N, Bits x, bool unsigned)
{
return Extend(x, N, unsigned);
}
// #impl-shared.HighestSetBit.1
public static int HighestSetBit(Bits x)
{
int N = x.Count;
for (int i = N - 1; i >= 0; i--)
{
if (x[i])
{
return i;
}
}
return -1;
}
// #impl-shared.Int.2
public static BigInteger Int(Bits x, bool unsigned)
{
return (unsigned ? UInt(x) : SInt(x));
}
// #impl-shared.IsOnes.1
public static bool IsOnes(Bits x)
{
int N = x.Count;
return (x == Ones(N));
}
// #impl-shared.IsZero.1
public static bool IsZero(Bits x)
{
int N = x.Count;
return (x == Zeros(N));
}
// #impl-shared.IsZeroBit.1
public static bool IsZeroBit(Bits x)
{
return IsZero(x);
}
// #impl-shared.LSL.2
public static Bits LSL(Bits x, int shift)
{
int N = x.Count;
/* assert shift >= 0; */
Bits result;
if (shift == 0)
{
result = new Bits(x);
}
else
{
(result, _) = LSL_C(x, shift);
}
return result;
}
// #impl-shared.LSL_C.2
public static (Bits, bool) LSL_C(Bits x, int shift)
{
int N = x.Count;
/* assert shift > 0; */
Bits extended_x = Bits.Concat(x, Zeros(shift));
Bits result = extended_x[N - 1, 0];
bool carry_out = extended_x[N];
return (result, carry_out);
}
// #impl-shared.LSR.2
public static Bits LSR(Bits x, int shift)
{
int N = x.Count;
/* assert shift >= 0; */
Bits result;
if (shift == 0)
{
result = new Bits(x);
}
else
{
(result, _) = LSR_C(x, shift);
}
return result;
}
// #impl-shared.LSR_C.2
public static (Bits, bool) LSR_C(Bits x, int shift)
{
int N = x.Count;
/* assert shift > 0; */
Bits extended_x = ZeroExtend(x, shift + N);
Bits result = extended_x[shift + N - 1, shift];
bool carry_out = extended_x[shift - 1];
return (result, carry_out);
}
// #impl-shared.Min.2
public static int Min(int a, int b)
{
if (a <= b)
{
return a;
}
else
{
return b;
}
}
/* #impl-shared.NOT.1 */
public static Bits NOT(Bits x)
{
return x.Not();
}
// #impl-shared.Ones.1
public static Bits Ones(int N)
{
return Replicate(true, N);
}
/* */
public static Bits OR(Bits x, Bits y)
{
return x.Or(y);
}
/* */
public static decimal Real(BigInteger value)
{
return (decimal)value;
}
// #impl-shared.ROR.2
public static Bits ROR(Bits x, int shift)
{
/* assert shift >= 0; */
Bits result;
if (shift == 0)
{
result = new Bits(x);
}
else
{
(result, _) = ROR_C(x, shift);
}
return result;
}
// #impl-shared.ROR_C.2
public static (Bits, bool) ROR_C(Bits x, int shift)
{
int N = x.Count;
/* assert shift != 0; */
int m = shift % N;
Bits result = OR(LSR(x, m), LSL(x, N - m));
bool carry_out = result[N - 1];
return (result, carry_out);
}
/* #impl-shared.Replicate.1 */
public static Bits Replicate(int N, Bits x)
{
int M = x.Count;
/* assert N MOD M == 0; */
return Replicate(x, N / M);
}
/* #impl-shared.Replicate.2 */
public static Bits Replicate(Bits x, int N)
{
int M = x.Count;
bool[] dst = new bool[M * N];
for (int i = 0; i < N; i++)
{
x.CopyTo(dst, i * M);
}
return new Bits(dst);
}
/* #impl-shared.RoundDown.1 */
public static BigInteger RoundDown(decimal x)
{
return (BigInteger)Decimal.Floor(x);
}
// #impl-shared.RoundTowardsZero.1
public static BigInteger RoundTowardsZero(decimal x)
{
if (x == 0.0m)
{
return (BigInteger)0m;
}
else if (x >= 0.0m)
{
return RoundDown(x);
}
else
{
return RoundUp(x);
}
}
/* #impl-shared.RoundUp.1 */
public static BigInteger RoundUp(decimal x)
{
return (BigInteger)Decimal.Ceiling(x);
}
// #impl-shared.SInt.1
public static BigInteger SInt(Bits x)
{
int N = x.Count;
BigInteger result = 0;
for (int i = 0; i <= N - 1; i++)
{
if (x[i])
{
result = result + BigInteger.Pow(2, i);
}
}
if (x[N - 1])
{
result = result - BigInteger.Pow(2, N);
}
return result;
}
// #impl-shared.SignExtend.2
public static Bits SignExtend(Bits x, int N)
{
int M = x.Count;
/* assert N >= M; */
return Bits.Concat(Replicate(x[M - 1], N - M), x);
}
/* #impl-shared.SignExtend.1 */
public static Bits SignExtend(int N, Bits x)
{
return SignExtend(x, N);
}
// #impl-shared.UInt.1
public static BigInteger UInt(Bits x)
{
int N = x.Count;
BigInteger result = 0;
for (int i = 0; i <= N - 1; i++)
{
if (x[i])
{
result = result + BigInteger.Pow(2, i);
}
}
return result;
}
// #impl-shared.ZeroExtend.2
public static Bits ZeroExtend(Bits x, int N)
{
int M = x.Count;
/* assert N >= M; */
return Bits.Concat(Zeros(N - M), x);
}
/* #impl-shared.ZeroExtend.1 */
public static Bits ZeroExtend(int N, Bits x)
{
return ZeroExtend(x, N);
}
// #impl-shared.Zeros.1
/* #impl-shared.Zeros.0 */
public static Bits Zeros(int N)
{
return Replicate(false, N);
}
#endregion
#region "functions/crc/"
// #impl-shared.BitReverse.1
public static Bits BitReverse(Bits data)
{
int N = data.Count;
Bits result = new Bits(N);
for (int i = 0; i <= N - 1; i++)
{
result[N - i - 1] = data[i];
}
return result;
}
// #impl-shared.Poly32Mod2.2
public static Bits Poly32Mod2(Bits _data, Bits poly)
{
int N = _data.Count;
/* assert N > 32; */
Bits data = new Bits(_data);
for (int i = N - 1; i >= 32; i--)
{
if (data[i])
{
data[i - 1, 0] = EOR(data[i - 1, 0], Bits.Concat(poly, Zeros(i - 32)));
}
}
return data[31, 0];
}
#endregion
#region "functions/integer/"
/* #impl-shared.AddWithCarry.3 */
public static (Bits, Bits) AddWithCarry(int N, Bits x, Bits y, bool carry_in)
{
BigInteger unsigned_sum = UInt(x) + UInt(y) + UInt(carry_in);
BigInteger signed_sum = SInt(x) + SInt(y) + UInt(carry_in);
Bits result = unsigned_sum.SubBigInteger(N - 1, 0); // same value as signed_sum<N-1:0>
bool n = result[N - 1];
bool z = IsZero(result);
bool c = !(UInt(result) == unsigned_sum);
bool v = !(SInt(result) == signed_sum);
return (result, Bits.Concat(n, z, c, v));
}
#endregion
#region "functions/registers/"
public static readonly Bits[] _R;
public static readonly Bits[] _V;
public static Bits SP_EL0;
public static Bits SP_EL1;
public static Bits FPSR; // FIXME: Temporary solution.
#endregion
#region "functions/system/"
// #impl-shared.ConditionHolds.1
public static bool ConditionHolds(Bits cond)
{
bool result;
// Evaluate base condition.
switch (cond[3, 1])
{
case Bits bits when bits == "000":
result = (PSTATE.Z == true); // EQ or NE
break;
case Bits bits when bits == "001":
result = (PSTATE.C == true); // CS or CC
break;
case Bits bits when bits == "010":
result = (PSTATE.N == true); // MI or PL
break;
case Bits bits when bits == "011":
result = (PSTATE.V == true); // VS or VC
break;
case Bits bits when bits == "100":
result = (PSTATE.C == true && PSTATE.Z == false); // HI or LS
break;
case Bits bits when bits == "101":
result = (PSTATE.N == PSTATE.V); // GE or LT
break;
case Bits bits when bits == "110":
result = (PSTATE.N == PSTATE.V && PSTATE.Z == false); // GT or LE
break;
default:
case Bits bits when bits == "111":
result = true; // AL
break;
}
// Condition flag values in the set '111x' indicate always true
// Otherwise, invert condition if necessary.
if (cond[0] == true && cond != "1111")
{
result = !result;
}
return result;
}
// #EL3
public static readonly Bits EL3 = "11";
// #EL2
public static readonly Bits EL2 = "10";
// #EL1
public static readonly Bits EL1 = "01";
// #EL0
public static readonly Bits EL0 = "00";
/* #impl-shared.HaveEL.1 */
public static bool HaveEL(Bits el)
{
if (el == EL1 || el == EL0)
{
return true; // EL1 and EL0 must exist
}
/* return boolean IMPLEMENTATION_DEFINED; */
return false;
}
public static ProcState PSTATE;
/* #ProcState */
internal struct ProcState
{
public void NZCV(Bits nzcv) // ASL: ".<,,,>".
{
N = nzcv[3];
Z = nzcv[2];
C = nzcv[1];
V = nzcv[0];
}
public void NZCV(bool n, bool z, bool c, bool v) // ASL: ".<,,,>".
{
N = n;
Z = z;
C = c;
V = v;
}
public bool N; // Negative condition flag
public bool Z; // Zero condition flag
public bool C; // Carry condition flag
public bool V; // oVerflow condition flag
public Bits EL; // Exception Level
public bool SP; // Stack pointer select: 0=SP0, 1=SPx [AArch64 only]
}
#endregion
#region "functions/vector/"
// #impl-shared.SatQ.3
public static (Bits, bool) SatQ(BigInteger i, int N, bool unsigned)
{
(Bits result, bool sat) = (unsigned ? UnsignedSatQ(i, N) : SignedSatQ(i, N));
return (result, sat);
}
// #impl-shared.SignedSatQ.2
public static (Bits, bool) SignedSatQ(BigInteger i, int N)
{
BigInteger result;
bool saturated;
if (i > BigInteger.Pow(2, N - 1) - 1)
{
result = BigInteger.Pow(2, N - 1) - 1;
saturated = true;
}
else if (i < -(BigInteger.Pow(2, N - 1)))
{
result = -(BigInteger.Pow(2, N - 1));
saturated = true;
}
else
{
result = i;
saturated = false;
}
return (result.SubBigInteger(N - 1, 0), saturated);
}
// #impl-shared.UnsignedSatQ.2
public static (Bits, bool) UnsignedSatQ(BigInteger i, int N)
{
BigInteger result;
bool saturated;
if (i > BigInteger.Pow(2, N) - 1)
{
result = BigInteger.Pow(2, N) - 1;
saturated = true;
}
else if (i < 0)
{
result = 0;
saturated = true;
}
else
{
result = i;
saturated = false;
}
return (result.SubBigInteger(N - 1, 0), saturated);
}
#endregion
}
}