Add function call support for OSX

Implements missing functionality in gdbserial to enable function calls
on OSX.

.travis.yml

@@ -7,9 +7,9 @@ os:
 
 go:
   - tip
+  - 1.11.x
   - 1.10.x
   - 1.9.x
-  - 1.8.x
 
 matrix:
   allow_failures:

pkg/proc/gdbserial/gdbserver.go

@@ -1189,8 +1189,9 @@ func (t *Thread) Registers(floatingPoint bool) (proc.Registers, error) {
 }
 
 func (t *Thread) RestoreRegisters(regs proc.SavedRegisters) error {
-	//TODO(aarzilli): implement
-	return errors.New("not implemented")
+	gdbregs := regs.(*gdbRegisters)
+	t.regs = *gdbregs
+	return t.writeRegisters()
 }
 
 func (t *Thread) Arch() proc.Arch {
@@ -1345,6 +1346,18 @@ func (t *Thread) writeSomeRegisters(regNames ...string) error {
 	return nil
 }
 
+func (t *Thread) writeRegisters() error {
+	if t.p.gcmdok {
+		return t.p.conn.writeRegisters(t.strID, t.regs.buf)
+	}
+	for _, r := range t.regs.regs {
+		if err := t.p.conn.writeRegister(t.strID, r.regnum, r.value); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
 func (t *Thread) readSomeRegisters(regNames ...string) error {
 	if t.p.gcmdok {
 		return t.p.conn.readRegisters(t.strID, t.regs.buf)

pkg/proc/test/support.go

@@ -250,7 +250,7 @@ func MustSupportFunctionCalls(t *testing.T, testBackend string) {
 	if !goversion.VersionAfterOrEqual(runtime.Version(), 1, 11) {
 		t.Skip("this version of Go does not support function calls")
 	}
-	if runtime.GOOS != "linux" || testBackend != "native" {
+	if runtime.GOOS == "windows" {
 		t.Skip("this backend does not support function calls")
 	}
 }