runtime: android/arm64 support

Not all tests passing yet, but a good chunk are.

Change-Id: I5daebaeabf3aecb380674ece8830a86751a8d139
Reviewed-on: https://go-review.googlesource.com/16458
Reviewed-by: Rahul Chaudhry <rahulchaudhry@google.com>
Reviewed-by: David Crawshaw <crawshaw@golang.org>

src/runtime/defs_linux_arm64.go

@@ -87,6 +87,10 @@ const (
 	_EPOLL_CTL_ADD = 0x1
 	_EPOLL_CTL_DEL = 0x2
 	_EPOLL_CTL_MOD = 0x3
+
+	_AF_UNIX    = 0x1
+	_F_SETFL    = 0x4
+	_SOCK_DGRAM = 0x2
 )
 
 type timespec struct {
@@ -167,6 +171,11 @@ type sigcontext struct {
 	__reserved [4096]byte
 }
 
+type sockaddr_un struct {
+	family uint16
+	path   [108]byte
+}
+
 type ucontext struct {
 	uc_flags    uint64
 	uc_link     *ucontext

src/runtime/rt0_android_arm64.s

@@ -0,0 +1,13 @@
+// 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 _rt0_arm64_android(SB),NOSPLIT,$-8
+	MOVD	$_rt0_arm64_linux(SB), R4
+	B	(R4)
+
+TEXT _rt0_arm64_android_lib(SB),NOSPLIT,$-8
+	MOVD	$_rt0_arm64_linux_lib(SB), R4
+	B	(R4)

src/runtime/sys_linux_arm64.s

@@ -43,6 +43,9 @@
 #define SYS_epoll_ctl		21
 #define SYS_epoll_pwait		22
 #define SYS_clock_gettime	113
+#define SYS_faccessat		48
+#define SYS_socket		198
+#define SYS_connect		203
 
 TEXT runtime·exit(SB),NOSPLIT,$-8-4
 	MOVW	code+0(FP), R0
@@ -445,3 +448,33 @@ TEXT runtime·closeonexec(SB),NOSPLIT,$-8
 	MOVD	$SYS_fcntl, R8
 	SVC
 	RET
+
+// int access(const char *name, int mode)
+TEXT runtime·access(SB),NOSPLIT,$0-20
+	MOVD	$AT_FDCWD, R0
+	MOVD	name+0(FP), R1
+	MOVW	mode+8(FP), R2
+	MOVD	$SYS_faccessat, R8
+	SVC
+	MOVW	R0, ret+16(FP)
+	RET
+
+// int connect(int fd, const struct sockaddr *addr, socklen_t len)
+TEXT runtime·connect(SB),NOSPLIT,$0-28
+	MOVW	fd+0(FP), R0
+	MOVD	addr+8(FP), R1
+	MOVW	len+16(FP), R2
+	MOVD	$SYS_connect, R8
+	SVC
+	MOVW	R0, ret+24(FP)
+	RET
+
+// int socket(int domain, int typ, int prot)
+TEXT runtime·socket(SB),NOSPLIT,$0-20
+	MOVW	domain+0(FP), R0
+	MOVW	typ+4(FP), R1
+	MOVW	prot+8(FP), R2
+	MOVD	$SYS_socket, R8
+	SVC
+	MOVW	R0, ret+16(FP)
+	RET

src/runtime/tls_arm64.h

@@ -2,7 +2,13 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+#ifdef GOOS_android
+#define TLS_linux
+#endif
 #ifdef GOOS_linux
+#define TLS_linux
+#endif
+#ifdef TLS_linux
 #define TPIDR TPIDR_EL0
 #define MRS_TPIDR_R0 WORD $0xd53bd040 // MRS TPIDR_EL0, R0
 #endif