Use "in" instead of "ref" for read-only SpanHelper methods

src/LibHac/Common/Buffer.cs

@@ -34,7 +34,7 @@ namespace LibHac.Common
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public static implicit operator ReadOnlySpan<byte>(in Buffer16 value)
         {
-            return SpanHelpers.AsReadOnlyByteSpan(ref Unsafe.AsRef(in value));
+            return SpanHelpers.AsReadOnlyByteSpan(in value);
         }
 
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
@@ -57,7 +57,7 @@ namespace LibHac.Common
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public readonly ReadOnlySpan<T> AsReadOnlySpan<T>() where T : unmanaged
         {
-            return SpanHelpers.AsReadOnlySpan<Buffer16, T>(ref Unsafe.AsRef(in this));
+            return SpanHelpers.AsReadOnlySpan<Buffer16, T>(in this);
         }
 
         public override string ToString()
@@ -93,7 +93,7 @@ namespace LibHac.Common
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public static implicit operator ReadOnlySpan<byte>(in Buffer32 value)
         {
-            return SpanHelpers.AsReadOnlyByteSpan(ref Unsafe.AsRef(in value));
+            return SpanHelpers.AsReadOnlyByteSpan(in value);
         }
 
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
@@ -116,7 +116,7 @@ namespace LibHac.Common
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public readonly ReadOnlySpan<T> AsReadOnlySpan<T>() where T : unmanaged
         {
-            return SpanHelpers.AsReadOnlySpan<Buffer32, T>(ref Unsafe.AsRef(in this));
+            return SpanHelpers.AsReadOnlySpan<Buffer32, T>(in this);
         }
 
         public override string ToString()

src/LibHac/Common/SpanHelpers.cs

@@ -33,29 +33,29 @@ namespace LibHac.Common
         }
 
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static ReadOnlySpan<T> CreateReadOnlySpan<T>(ref T reference, int length)
+        public static ReadOnlySpan<T> CreateReadOnlySpan<T>(in T reference, int length)
         {
-            return MemoryMarshal.CreateReadOnlySpan(ref reference, length);
+            return MemoryMarshal.CreateReadOnlySpan(ref Unsafe.AsRef(in reference), length);
         }
 
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static ReadOnlySpan<T> AsReadOnlySpan<T>(ref T reference) where T : unmanaged
+        public static ReadOnlySpan<T> AsReadOnlySpan<T>(in T reference) where T : unmanaged
         {
-            return CreateReadOnlySpan(ref reference, 1);
+            return CreateReadOnlySpan(in reference, 1);
         }
 
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static ReadOnlySpan<TSpan> AsReadOnlySpan<TStruct, TSpan>(ref TStruct reference)
+        public static ReadOnlySpan<TSpan> AsReadOnlySpan<TStruct, TSpan>(in TStruct reference)
             where TStruct : unmanaged where TSpan : unmanaged
         {
-            return CreateReadOnlySpan(ref Unsafe.As<TStruct, TSpan>(ref reference),
+            return CreateReadOnlySpan(in Unsafe.As<TStruct, TSpan>(ref Unsafe.AsRef(in reference)),
                 Unsafe.SizeOf<TStruct>() / Unsafe.SizeOf<TSpan>());
         }
 
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static ReadOnlySpan<byte> AsReadOnlyByteSpan<T>(ref T reference) where T : unmanaged
+        public static ReadOnlySpan<byte> AsReadOnlyByteSpan<T>(in T reference) where T : unmanaged
         {
-            return CreateReadOnlySpan(ref Unsafe.As<T, byte>(ref reference), Unsafe.SizeOf<T>());
+            return CreateReadOnlySpan(in Unsafe.As<T, byte>(ref Unsafe.AsRef(in reference)), Unsafe.SizeOf<T>());
         }
 
         // All AsStruct methods do bounds checks on the input

src/LibHac/Diag/Assert.cs

@@ -1,4 +1,5 @@
-using System.Diagnostics;
+using System;
+using System.Diagnostics;
 using System.Diagnostics.CodeAnalysis;
 
 namespace LibHac.Diag
@@ -42,5 +43,21 @@ namespace LibHac.Diag
                 throw new LibHacException($"Value {value} is not in the range {lowerInclusive} to {upperExclusive}");
             }
         }
+
+        public static void Equal<T>(T value1, T value2) where T : IEquatable<T>
+        {
+            if (!value1.Equals(value2))
+            {
+                throw new LibHacException($"Values were not equal: {value1}, {value2}");
+            }
+        }
+
+        public static void NotEqual<T>(T value1, T value2) where T : IEquatable<T>
+        {
+            if (value1.Equals(value2))
+            {
+                throw new LibHacException($"Values should not be equal: {value1}, {value2}");
+            }
+        }
     }
 }

src/LibHac/FsSystem/FsPath.cs

@@ -33,7 +33,7 @@ namespace LibHac.FsSystem
         }
 
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static implicit operator U8Span(in FsPath value) => new U8Span(SpanHelpers.AsReadOnlyByteSpan(ref Unsafe.AsRef(in value)));
+        public static implicit operator U8Span(in FsPath value) => new U8Span(SpanHelpers.AsReadOnlyByteSpan(in value));
 
         public override string ToString() => StringUtils.Utf8ZToString(Str);
     }

src/LibHac/Sm/ServiceManager.cs

@@ -76,7 +76,7 @@ namespace LibHac.Sm
             int nameLen;
             for (nameLen = 1; nameLen < Unsafe.SizeOf<ServiceName>(); nameLen++)
             {
-                if (SpanHelpers.AsReadOnlyByteSpan(ref name)[nameLen] == 0)
+                if (SpanHelpers.AsReadOnlyByteSpan(in name)[nameLen] == 0)
                 {
                     break;
                 }
@@ -85,7 +85,7 @@ namespace LibHac.Sm
             // Names must be all-zero after they end.
             for (; nameLen < Unsafe.SizeOf<ServiceName>(); nameLen++)
             {
-                if (SpanHelpers.AsReadOnlyByteSpan(ref name)[nameLen] != 0)
+                if (SpanHelpers.AsReadOnlyByteSpan(in name)[nameLen] != 0)
                 {
                     return ResultSm.InvalidServiceName.Log();
                 }

src/LibHac/Sm/ServiceName.cs

@@ -37,7 +37,7 @@ namespace LibHac.Sm
         public override string ToString()
         {
             ulong name = Name;
-            return StringUtils.Utf8ZToString(SpanHelpers.AsReadOnlyByteSpan(ref name));
+            return StringUtils.Utf8ZToString(SpanHelpers.AsReadOnlyByteSpan(in name));
         }
     }
 }

src/hactoolnet/ProcessNax0.cs

@@ -60,7 +60,7 @@ namespace hactoolnet
             AesXtsFileHeader header = xtsFile.Header;
             uint magic = header.Magic;
 
-            PrintItem(sb, colLen, "    Magic:", Utilities.GetUtf8String(SpanHelpers.AsReadOnlyByteSpan(ref magic)));
+            PrintItem(sb, colLen, "    Magic:", Utilities.GetUtf8String(SpanHelpers.AsReadOnlyByteSpan(in magic)));
             PrintItem(sb, colLen, "    Content Type:", GetContentType(contentType));
             PrintItem(sb, colLen, "    Content Size:", $"{header.Size:x12}");
             PrintItem(sb, colLen, "    Header HMAC:", header.Signature);