Tweaks

jamescourtney · Nov 17, 2024 · 2ad57fb · 2ad57fb
1 parent 4987cd7
commit 2ad57fb
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Showing 2 changed files with 17 additions and 5 deletions.
diff --git a/src/Benchmarks/Benchmark/Program.cs b/src/Benchmarks/Benchmark/Program.cs
@@ -58,14 +58,14 @@ public static void Main(string[] args)
 #else
                 .WithRuntime(CoreRuntime.Core80)
 #endif
-                ;
+            ;
 
             // job = job.WithEnvironmentVariable(new EnvironmentVariable("DOTNET_TieredPGO", "0"));
 
             var config = DefaultConfig.Instance
                  .AddColumn(new[] { StatisticColumn.P25, StatisticColumn.P95 })
                  .AddDiagnoser(MemoryDiagnoser.Default)
-                 .AddJob(job);
+                 .AddJob(job.DontEnforcePowerPlan());
 
             summaries.Add(BenchmarkRunner.Run(typeof(FBBench.FBSerializeBench), config));
             summaries.Add(BenchmarkRunner.Run(typeof(FBBench.FBDeserializeBench), config));

diff --git a/src/FlatSharp.Runtime/IO/SerializationTarget/BigSpan.cs b/src/FlatSharp.Runtime/IO/SerializationTarget/BigSpan.cs
@@ -214,7 +214,8 @@ public long WriteAndProvisionString(
         int maxItems = encoding.GetMaxByteCount(value.Length) + 1;
         long stringStartOffset = context.AllocateVector(sizeof(byte), maxItems, sizeof(byte));
 
-        Span<byte> destination = this.ToSpan(stringStartOffset + sizeof(uint), maxItems);
+        BigSpan scopedThis = this.Slice(stringStartOffset, maxItems + sizeof(uint));
+        Span<byte> destination = scopedThis.ToSpan(sizeof(uint), maxItems);
 
 #if NETSTANDARD2_0
         int length = value.Length;
@@ -227,10 +228,10 @@ public long WriteAndProvisionString(
 #endif
 
         // null teriminator
-        this[stringStartOffset + bytesWritten + sizeof(uint)] = 0;
+        scopedThis.WriteUnalignedUnsafe<byte>(sizeof(uint) + bytesWritten, 0);
 
         // write length
-        this.WriteInt(stringStartOffset, bytesWritten);
+        scopedThis.WriteUnalignedUnsafe<int>(0, bytesWritten);
 
         // give back unused space. Account for null terminator.
         context.Offset -= maxItems - (bytesWritten + 1);
@@ -262,8 +263,19 @@ private void WriteUnaligned<T>(long offset, T value)
         where T : unmanaged
     {
         CheckAlignment(offset, Unsafe.SizeOf<T>());
+        var slice = this.ToSpan(offset, Unsafe.SizeOf<T>());
+        this.WriteUnalignedUnsafe(offset, value);
+    }
+
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    private void WriteUnalignedUnsafe<T>(long offset, T value)
+    {
+#if NET7_0_OR_GREATER
+        Unsafe.WriteUnaligned(ref Unsafe.Add(ref this.value, (IntPtr)offset), value);
+#else
         var slice = this.ToSpan(offset, Unsafe.SizeOf<T>());
         Unsafe.WriteUnaligned(ref slice[0], value);
+#endif
     }
 
     private static double ReverseEndianness(double value)