Try out a PackedSimd WideningLoader

lewing · lewing · commit ca77dffa0974 · 2025-04-17T18:55:44.000-05:00
diff --git a/src/libraries/System.Private.CoreLib/src/System/Text/Ascii.Equality.cs b/src/libraries/System.Private.CoreLib/src/System/Text/Ascii.Equality.cs
@@ -522,6 +522,11 @@ public static Vector128<ushort> Load128(ref byte ptr)
                     Vector128<byte> vec = Vector128.CreateScalarUnsafe(Unsafe.ReadUnaligned<long>(ref ptr)).AsByte();
                     return Sse2.UnpackLow(vec, Vector128<byte>.Zero).AsUInt16();
                 }
+                else if (PackedSimd.IsSupported)
+                {
+                    Vector128<byte> vec = Vector128.CreateScalarUnsafe(Unsafe.ReadUnaligned<long>(ref ptr)).AsByte();
+                    return PackeSimd.ZeroExtendWideningLower(vec);
+                }
                 else
                 {
                     (Vector64<ushort> lower, Vector64<ushort> upper) = Vector64.Widen(Vector64.LoadUnsafe(ref ptr));

Original file line number	Diff line number	Diff line change
`@@ -522,6 +522,11 @@ public static Vector128<ushort> Load128(ref byte ptr)`
`522`	`522`	`Vector128<byte> vec = Vector128.CreateScalarUnsafe(Unsafe.ReadUnaligned<long>(ref ptr)).AsByte();`
`523`	`523`	`return Sse2.UnpackLow(vec, Vector128<byte>.Zero).AsUInt16();`
`524`	`524`	`}`
	`525`	`+ else if (PackedSimd.IsSupported)`
	`526`	`+ {`
	`527`	`+ Vector128<byte> vec = Vector128.CreateScalarUnsafe(Unsafe.ReadUnaligned<long>(ref ptr)).AsByte();`
	`528`	`+ return PackeSimd.ZeroExtendWideningLower(vec);`
	`529`	`+ }`
`525`	`530`	`else`
`526`	`531`	`{`
`527`	`532`	`(Vector64<ushort> lower, Vector64<ushort> upper) = Vector64.Widen(Vector64.LoadUnsafe(ref ptr));`