runtime/internal/atomic: unify sys_*_arm.s on non-linux

Updates #23778.

Change-Id: I80e57a15b6e3bbc2e25ea186399ff0e360fc5c21
Reviewed-on: https://go-review.googlesource.com/93635
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>

src/runtime/internal/atomic/sys_darwin_arm.s

-// Copyright 2015 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.
-
-#include "textflag.h"
-
-TEXT runtime∕internal∕atomic·Cas(SB),NOSPLIT,$0
-	B	runtime∕internal∕atomic·armcas(SB)
-
-TEXT runtime∕internal∕atomic·Casp1(SB),NOSPLIT,$0
-	B	runtime∕internal∕atomic·Cas(SB)

src/runtime/internal/atomic/sys_nacl_arm.s

-// Copyright 2015 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.
-
-#include "textflag.h"
-
-// This is only valid for ARMv6+, however, NaCl/ARM is only defined
-// for ARMv7A anyway.
-TEXT runtime∕internal∕atomic·Cas(SB),NOSPLIT,$0
-	B	runtime∕internal∕atomic·armcas(SB)
-
-TEXT runtime∕internal∕atomic·Casp1(SB),NOSPLIT,$0
-	B	runtime∕internal∕atomic·Cas(SB)

src/runtime/internal/atomic/sys_netbsd_arm.s

-// Copyright 2015 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.
-
-#include "textflag.h"
-
-// TODO(minux): this is only valid for ARMv6+
-// bool Armcas(int32 *val, int32 old, int32 new)
-// Atomically:
-//	if(*val == old){
-//		*val = new;
-//		return 1;
-//	}else
-//		return 0;
-TEXT runtime∕internal∕atomic·Cas(SB),NOSPLIT,$0
-	B	runtime∕internal∕atomic·armcas(SB)
-
-TEXT runtime∕internal∕atomic·Casp1(SB),NOSPLIT,$0
-	B	runtime∕internal∕atomic·Cas(SB)
-
-

src/runtime/internal/atomic/sys_freebsd_arm.s → src/runtime/internal/atomic/sys_nonlinux_arm.s

@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build !linux,arm
+
 #include "textflag.h"
 
 // TODO(minux): this is only valid for ARMv6+
@@ -12,8 +14,8 @@
 //		return 1;
 //	}else
 //		return 0;
-TEXT runtime∕internal∕atomic·Cas(SB),NOSPLIT,$0
-	B	runtime∕internal∕atomic·armcas(SB)
+TEXT	·Cas(SB),NOSPLIT,$0
+	JMP	·armcas(SB)
 
-TEXT runtime∕internal∕atomic·Casp1(SB),NOSPLIT,$0
-	B	runtime∕internal∕atomic·Cas(SB)
+TEXT	·Casp1(SB),NOSPLIT,$0
+	JMP	·Cas(SB)

src/runtime/internal/atomic/sys_openbsd_arm.s

-// Copyright 2015 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.
-
-#include "textflag.h"
-
-TEXT runtime∕internal∕atomic·Cas(SB),NOSPLIT,$0
-	B	runtime∕internal∕atomic·armcas(SB)
-
-TEXT runtime∕internal∕atomic·Casp1(SB),NOSPLIT,$0
-	B	runtime∕internal∕atomic·Cas(SB)

src/runtime/internal/atomic/sys_plan9_arm.s

-// Copyright 2015 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.
-
-#include "textflag.h"
-
-TEXT runtime∕internal∕atomic·Cas(SB),NOSPLIT,$0
-	B	runtime∕internal∕atomic·armcas(SB)
-
-TEXT runtime∕internal∕atomic·Casp1(SB),NOSPLIT,$0
-	B	runtime∕internal∕atomic·Cas(SB)