the definitive tun offloads branch (#1704)

overlay/checksum/export_amd64_test.go

@@ -0,0 +1,11 @@
+package checksum
+
+// archImpls exposes every hand-written implementation on this architecture
+// so the tests exercise them directly, independent of what the public
+// Checksum dispatches to on the running CPU. Without this, running the
+// suite on a non-AVX2 machine compared gvisor against itself and left the
+// assembly untested — silently. available=false makes the test skip loudly
+// instead.
+var archImpls = []archImpl{
+	{name: "avx2", fn: checksumAVX2, available: hasAVX2},
+}