[dev.cc] runtime: convert freebsd to Go

It builds.
Don't know if it works, but it's a lot closer than having everything in C.

LGTM=r
R=r
CC=golang-codereviews
https://codereview.appspot.com/168590043

1 files changed, 17 insertions, 0 deletions

diff --git a/src/runtime/os_freebsd_arm.go b/src/runtime/os_freebsd_arm.go
new file mode 100644
index 000000000..e049cbf9a
--- /dev/null
+++ b/src/runtime/os_freebsd_arm.go
@@ -0,0 +1,17 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+func checkgoarm() {
+	// TODO(minux)
+}
+
+//go:nosplit
+func cputicks() int64 {
+	// Currently cputicks() is used in blocking profiler and to seed runtime·fastrand1().
+	// runtime·nanotime() is a poor approximation of CPU ticks that is enough for the profiler.
+	// TODO: need more entropy to better seed fastrand1.
+	return nanotime()
+}