[llgo] Roll gofrontend forward

Switch gofrontend to using go.googlesource.com, and
update to 81eb6a3f425b2158c67ee32c0cc973a72ce9d6be.

There are various changes required to update to the
go 1.5 runtime:

typemap.go is changed to accommodate the change in representation for equal/hash algorithms, and the removal of the zero value/type.
CMakeLists.txt is updated to add the build tree to the package search path, so internal packages, which are not installed, are found.
various files changes due to removal of __go_new_nopointers; the same change as in D11863, but with NoUnwindAttribute added to the added runtime functions which are called with "callOnly".
minor cleanups in ssa.go while investigating issues with unwinding/panic handling.

Differential Revisision: http://reviews.llvm.org/D15188

llvm-svn: 263536

1 files changed, 15 insertions, 0 deletions

diff --git a/llgo/third_party/gofrontend/libgo/go/reflect/example_test.go b/llgo/third_party/gofrontend/libgo/go/reflect/example_test.go
index cca28eeece8..8ebf9765b8d 100644
--- a/llgo/third_party/gofrontend/libgo/go/reflect/example_test.go
+++ b/llgo/third_party/gofrontend/libgo/go/reflect/example_test.go
@@ -6,6 +6,8 @@ package reflect_test
 
 import (
 	"fmt"
+	"io"
+	"os"
 	"reflect"
 )
 
@@ -64,3 +66,16 @@ func ExampleStructTag() {
 	// Output:
 	// blue gopher
 }
+
+func ExampleTypeOf() {
+	// As interface types are only used for static typing, a
+	// common idiom to find the reflection Type for an interface
+	// type Foo is to use a *Foo value.
+	writerType := reflect.TypeOf((*io.Writer)(nil)).Elem()
+
+	fileType := reflect.TypeOf((*os.File)(nil))
+	fmt.Println(fileType.Implements(writerType))
+
+	// Output:
+	// true
+}