runtime: add s390x support (modified files only)

Change-Id: Ib79ad4a890994ad64edb1feb79bd242d26b5b08a
Reviewed-on: https://go-review.googlesource.com/20945
Reviewed-by: Minux Ma <minux@golang.org>
Run-TryBot: Michael Munday <munday@ca.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

src/runtime/cgocall.go

@@ -246,8 +246,8 @@ func cgocallbackg1() {
 	case "386":
 		// On 386, stack frame is three words, plus caller PC.
 		cb = (*args)(unsafe.Pointer(sp + 4*sys.PtrSize))
-	case "ppc64", "ppc64le":
+	case "ppc64", "ppc64le", "s390x":
-		// On ppc64, the callback arguments are in the arguments area of
+		// On ppc64 and s390x, the callback arguments are in the arguments area of
 		// cgocallback's stack frame. The stack looks like this:
 		// +--------------------+------------------------------+
 		// |                    | ...                          |
@@ -300,7 +300,7 @@ func unwindm(restore *bool) {
 	switch GOARCH {
 	default:
 		throw("unwindm not implemented")
-	case "386", "amd64", "arm", "ppc64", "ppc64le":
+	case "386", "amd64", "arm", "ppc64", "ppc64le", "s390x":
 		sched.sp = *(*uintptr)(unsafe.Pointer(sched.sp + sys.MinFrameSize))
 	case "arm64":
 		sched.sp = *(*uintptr)(unsafe.Pointer(sched.sp + 16))

src/runtime/extern.go

@@ -227,5 +227,5 @@ func Version() string {
 const GOOS string = sys.TheGoos
 
 // GOARCH is the running program's architecture target:
-// 386, amd64, or arm.
+// 386, amd64, arm, or s390x.
 const GOARCH string = sys.TheGoarch

src/runtime/gcinfo_test.go

@@ -144,7 +144,7 @@ func infoBigStruct() []byte {
 			typeScalar, typeScalar, typeScalar, typeScalar, // t int; y uint16; u uint64
 			typePointer, typeScalar, // i string
 		}
-	case "arm64", "amd64", "mips64", "mips64le", "ppc64", "ppc64le":
+	case "arm64", "amd64", "mips64", "mips64le", "ppc64", "ppc64le", "s390x":
 		return []byte{
 			typePointer,                        // q *int
 			typeScalar, typeScalar, typeScalar, // w byte; e [17]byte

src/runtime/hash64.go

@@ -6,7 +6,7 @@
 //   xxhash: https://code.google.com/p/xxhash/
 // cityhash: https://code.google.com/p/cityhash/
 
-// +build amd64 amd64p32 arm64 mips64 mips64le ppc64 ppc64le
+// +build amd64 amd64p32 arm64 mips64 mips64le ppc64 ppc64le s390x
 
 package runtime
 

src/runtime/noasm.go

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// Routines that are implemented in assembly in asm_{amd64,386,arm,arm64,ppc64x}.s
+// Routines that are implemented in assembly in asm_{amd64,386,arm,arm64,ppc64x,s390x}.s
 
 // +build mips64 mips64le
 

src/runtime/os1_linux_generic.go

@@ -4,6 +4,7 @@
 
 // +build !mips64
 // +build !mips64le
+// +build !s390x
 // +build linux
 
 package runtime

src/runtime/os2_linux_generic.go

@@ -4,6 +4,7 @@
 
 // +build !mips64
 // +build !mips64le
+// +build !s390x
 // +build linux
 
 package runtime

src/runtime/runtime-gdb_test.go

@@ -104,7 +104,7 @@ func TestGdbPython(t *testing.T) {
 	// stack frames on RISC architectures.
 	canBackTrace := false
 	switch runtime.GOARCH {
-	case "amd64", "386", "ppc64", "ppc64le", "arm", "arm64", "mips64", "mips64le":
+	case "amd64", "386", "ppc64", "ppc64le", "arm", "arm64", "mips64", "mips64le", "s390x":
 		canBackTrace = true
 		args = append(args,
 			"-ex", "echo BEGIN goroutine 2 bt\n",

src/runtime/unaligned1.go

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build 386 amd64 amd64p32 arm64 ppc64 ppc64le
+// +build 386 amd64 amd64p32 arm64 ppc64 ppc64le s390x
 
 package runtime