syscall: new files for plan_arm support

Implementation closely follows plan9_386 version.

Change-Id: Ifb76e001fb5664e6a23541cf4768d7f11b2be68b
Reviewed-on: https://go-review.googlesource.com/18967Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

src/syscall/asm_plan9_arm.s

+// Copyright 2009 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"
+
+#define SYS_SEEK 39	/* from zsysnum_plan9.go */
+
+// System call support for plan9 on arm
+
+TEXT	sysresult<>(SB),NOSPLIT,$12
+	MOVW	$runtime·emptystring+0(SB), R2
+	CMP		$-1, R0
+	B.NE	ok
+	MOVW	R1, save-4(SP)
+	BL		runtime·errstr(SB)
+	MOVW	save-4(SP), R1
+	MOVW	$err-12(SP), R2
+ok:
+	MOVM.IA	(R2), [R3-R4]
+	MOVM.IA	[R3-R4], (R1)
+	RET
+	
+//func Syscall(trap, a1, a2, a3 uintptr) (r1, r2 uintptr, err ErrorString)
+TEXT	·Syscall(SB),NOSPLIT,$0
+	BL		runtime·entersyscall(SB)
+	MOVW	trap+0(FP), R0	// syscall num
+	MOVM.IA.W	(R13),[R1-R2]	// pop LR and caller's LR
+	SWI		0
+	MOVM.DB.W	[R1-R2],(R13)	// push LR and caller's LR
+	MOVW	$0, R2
+	MOVW	$r1+16(FP), R1
+	MOVM.IA.W	[R0,R2], (R1)
+	BL		sysresult<>(SB)
+	BL		runtime·exitsyscall(SB)
+	RET
+
+//func Syscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err ErrorString)
+// Actually Syscall5 but the rest of the code expects it to be named Syscall6.
+TEXT	·Syscall6(SB),NOSPLIT,$0
+	BL		runtime·entersyscall(SB)
+	MOVW	trap+0(FP), R0	// syscall num
+	MOVM.IA.W	(R13),[R1-R2]	// pop LR and caller's LR
+	SWI		0
+	MOVM.DB.W	[R1-R2],(R13)	// push LR and caller's LR
+	MOVW	$0, R1
+	MOVW	$r1+28(FP), R1
+	MOVM.IA.W	[R0,R2], (R1)
+	BL		sysresult<>(SB)
+	BL		runtime·exitsyscall(SB)
+	RET
+
+//func RawSyscall(trap, a1, a2, a3 uintptr) (r1, r2, err uintptr)
+TEXT ·RawSyscall(SB),NOSPLIT,$0
+	MOVW	trap+0(FP), R0	// syscall num
+	MOVM.IA.W	(R13),[R1]		// pop caller's LR
+	SWI		0
+	MOVM.DB.W	[R1],(R13)		// push caller's LR
+	MOVW	R0, r1+16(FP)
+	MOVW	R0, r2+20(FP)
+	MOVW	R0, err+24(FP)
+	RET
+
+//func RawSyscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, err uintptr)
+// Actually RawSyscall5 but the rest of the code expects it to be named RawSyscall6.
+TEXT	·RawSyscall6(SB),NOSPLIT,$0
+	MOVW	trap+0(FP), R0	// syscall num
+	MOVM.IA.W	(R13),[R1]		// pop caller's LR
+	SWI		0
+	MOVM.DB.W	[R1],(R13)		// push caller's LR
+	MOVW	R0, r1+28(FP)
+	MOVW	R0, r2+32(FP)
+	MOVW	R0, err+36(FP)
+	RET
+
+//func seek(placeholder uintptr, fd int, offset int64, whence int) (newoffset int64, err string)
+TEXT ·seek(SB),NOSPLIT,$0
+	MOVW	$newoffset_lo+20(FP), R5
+	MOVW	R5, placeholder+0(FP)	//placeholder = dest for return value
+	MOVW	$SYS_SEEK, R0		// syscall num
+	MOVM.IA.W	(R13),[R1]		// pop LR
+	SWI		0
+	MOVM.DB.W	[R1],(R13)		// push LR
+	CMP		$-1, R0
+	MOVW.EQ	R0, 0(R5)
+	MOVW.EQ	R0, 4(R5)
+	MOVW	$err+28(FP), R1
+	BL		sysresult<>(SB)
+	RET
+
+//func exit(code int)
+// Import runtime·exit for cleanly exiting.
+TEXT ·exit(SB),NOSPLIT,$4
+	MOVW	code+0(FP), R0
+	MOVW	R0, e-4(SP)
+	BL		runtime·exit(SB)
+	RET

src/syscall/zsyscall_plan9_arm.go

+// mksyscall.pl -l32 -plan9 syscall_plan9.go
+// MACHINE GENERATED BY THE COMMAND ABOVE; DO NOT EDIT
+
+// +build arm,plan9
+
+package syscall
+
+import "unsafe"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func fd2path(fd int, buf []byte) (err error) {
+	var _p0 unsafe.Pointer
+	if len(buf) > 0 {
+		_p0 = unsafe.Pointer(&buf[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_FD2PATH, uintptr(fd), uintptr(_p0), uintptr(len(buf)))
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func pipe(p *[2]int32) (err error) {
+	r0, _, e1 := Syscall(SYS_PIPE, uintptr(unsafe.Pointer(p)), 0, 0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func await(s []byte) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(s) > 0 {
+		_p0 = unsafe.Pointer(&s[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_AWAIT, uintptr(_p0), uintptr(len(s)), 0)
+	n = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func open(path string, mode int) (fd int, err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall(SYS_OPEN, uintptr(unsafe.Pointer(_p0)), uintptr(mode), 0)
+	use(unsafe.Pointer(_p0))
+	fd = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func create(path string, mode int, perm uint32) (fd int, err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall(SYS_CREATE, uintptr(unsafe.Pointer(_p0)), uintptr(mode), uintptr(perm))
+	use(unsafe.Pointer(_p0))
+	fd = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func remove(path string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall(SYS_REMOVE, uintptr(unsafe.Pointer(_p0)), 0, 0)
+	use(unsafe.Pointer(_p0))
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func stat(path string, edir []byte) (n int, err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	var _p1 unsafe.Pointer
+	if len(edir) > 0 {
+		_p1 = unsafe.Pointer(&edir[0])
+	} else {
+		_p1 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_STAT, uintptr(unsafe.Pointer(_p0)), uintptr(_p1), uintptr(len(edir)))
+	use(unsafe.Pointer(_p0))
+	n = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func bind(name string, old string, flag int) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(name)
+	if err != nil {
+		return
+	}
+	var _p1 *byte
+	_p1, err = BytePtrFromString(old)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall(SYS_BIND, uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(_p1)), uintptr(flag))
+	use(unsafe.Pointer(_p0))
+	use(unsafe.Pointer(_p1))
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func mount(fd int, afd int, old string, flag int, aname string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(old)
+	if err != nil {
+		return
+	}
+	var _p1 *byte
+	_p1, err = BytePtrFromString(aname)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall6(SYS_MOUNT, uintptr(fd), uintptr(afd), uintptr(unsafe.Pointer(_p0)), uintptr(flag), uintptr(unsafe.Pointer(_p1)), 0)
+	use(unsafe.Pointer(_p0))
+	use(unsafe.Pointer(_p1))
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func wstat(path string, edir []byte) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	var _p1 unsafe.Pointer
+	if len(edir) > 0 {
+		_p1 = unsafe.Pointer(&edir[0])
+	} else {
+		_p1 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_WSTAT, uintptr(unsafe.Pointer(_p0)), uintptr(_p1), uintptr(len(edir)))
+	use(unsafe.Pointer(_p0))
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func chdir(path string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall(SYS_CHDIR, uintptr(unsafe.Pointer(_p0)), 0, 0)
+	use(unsafe.Pointer(_p0))
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Dup(oldfd int, newfd int) (fd int, err error) {
+	r0, _, e1 := Syscall(SYS_DUP, uintptr(oldfd), uintptr(newfd), 0)
+	fd = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Pread(fd int, p []byte, offset int64) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(p) > 0 {
+		_p0 = unsafe.Pointer(&p[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall6(SYS_PREAD, uintptr(fd), uintptr(_p0), uintptr(len(p)), uintptr(offset), uintptr(offset>>32), 0)
+	n = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Pwrite(fd int, p []byte, offset int64) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(p) > 0 {
+		_p0 = unsafe.Pointer(&p[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall6(SYS_PWRITE, uintptr(fd), uintptr(_p0), uintptr(len(p)), uintptr(offset), uintptr(offset>>32), 0)
+	n = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Close(fd int) (err error) {
+	r0, _, e1 := Syscall(SYS_CLOSE, uintptr(fd), 0, 0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Fstat(fd int, edir []byte) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(edir) > 0 {
+		_p0 = unsafe.Pointer(&edir[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_FSTAT, uintptr(fd), uintptr(_p0), uintptr(len(edir)))
+	n = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Fwstat(fd int, edir []byte) (err error) {
+	var _p0 unsafe.Pointer
+	if len(edir) > 0 {
+		_p0 = unsafe.Pointer(&edir[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_FWSTAT, uintptr(fd), uintptr(_p0), uintptr(len(edir)))
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}