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Diffstat (limited to 'ChocolArm64/Decoders/DecoderHelper.cs')
-rw-r--r--ChocolArm64/Decoders/DecoderHelper.cs112
1 files changed, 0 insertions, 112 deletions
diff --git a/ChocolArm64/Decoders/DecoderHelper.cs b/ChocolArm64/Decoders/DecoderHelper.cs
deleted file mode 100644
index 2209472b..00000000
--- a/ChocolArm64/Decoders/DecoderHelper.cs
+++ /dev/null
@@ -1,112 +0,0 @@
-using System;
-
-namespace ChocolArm64.Decoders
-{
- static class DecoderHelper
- {
- public struct BitMask
- {
- public long WMask;
- public long TMask;
- public int Pos;
- public int Shift;
- public bool IsUndefined;
-
- public static BitMask Invalid => new BitMask { IsUndefined = true };
- }
-
- public static BitMask DecodeBitMask(int opCode, bool immediate)
- {
- int immS = (opCode >> 10) & 0x3f;
- int immR = (opCode >> 16) & 0x3f;
-
- int n = (opCode >> 22) & 1;
- int sf = (opCode >> 31) & 1;
-
- int length = BitUtils.HighestBitSet32((~immS & 0x3f) | (n << 6));
-
- if (length < 1 || (sf == 0 && n != 0))
- {
- return BitMask.Invalid;
- }
-
- int size = 1 << length;
-
- int levels = size - 1;
-
- int s = immS & levels;
- int r = immR & levels;
-
- if (immediate && s == levels)
- {
- return BitMask.Invalid;
- }
-
- long wMask = BitUtils.FillWithOnes(s + 1);
- long tMask = BitUtils.FillWithOnes(((s - r) & levels) + 1);
-
- if (r > 0)
- {
- wMask = BitUtils.RotateRight(wMask, r, size);
- wMask &= BitUtils.FillWithOnes(size);
- }
-
- return new BitMask()
- {
- WMask = BitUtils.Replicate(wMask, size),
- TMask = BitUtils.Replicate(tMask, size),
-
- Pos = immS,
- Shift = immR
- };
- }
-
- public static long DecodeImm8Float(long imm, int size)
- {
- int e = 0, f = 0;
-
- switch (size)
- {
- case 0: e = 8; f = 23; break;
- case 1: e = 11; f = 52; break;
-
- default: throw new ArgumentOutOfRangeException(nameof(size));
- }
-
- long value = (imm & 0x3f) << f - 4;
-
- long eBit = (imm >> 6) & 1;
- long sBit = (imm >> 7) & 1;
-
- if (eBit != 0)
- {
- value |= (1L << e - 3) - 1 << f + 2;
- }
-
- value |= (eBit ^ 1) << f + e - 1;
- value |= sBit << f + e;
-
- return value;
- }
-
- public static long DecodeImm24_2(int opCode)
- {
- return ((long)opCode << 40) >> 38;
- }
-
- public static long DecodeImm26_2(int opCode)
- {
- return ((long)opCode << 38) >> 36;
- }
-
- public static long DecodeImmS19_2(int opCode)
- {
- return (((long)opCode << 40) >> 43) & ~3;
- }
-
- public static long DecodeImmS14_2(int opCode)
- {
- return (((long)opCode << 45) >> 48) & ~3;
- }
- }
-} \ No newline at end of file