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// Copyright 2017 The Fuchsia 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 "syscall-entry.h"
#include "zircon-syscall-arm64.S"
#include <lib/syscalls/zx-syscall-numbers.h>
.cfi_sections .eh_frame, .debug_frame
// (vmar_handle: x0, addr: x1, len: x2, handle: x3)
syscall_entry_begin zx_vmar_unmap_handle_close_thread_exit
// Save the handle argument in a callee-saves register (x19).
// Callee-save that register so we can unwind in the error case.
// We only need to save x19, but we have to keep SP aligned to 16
// bytes, so we always push and pop registers in pairs.
push_regpair x19, x20
mov x19, x3
zircon_syscall ZX_SYS_vmar_unmap, zx_vmar_unmap, zx_vmar_unmap_handle_close_thread_exit
cbnz x0, .Lvmar_unmap_fail
// Now the stack is gone and we can never return!
mov x0, x19
zircon_syscall ZX_SYS_handle_close, zx_handle_close, zx_vmar_unmap_handle_close_thread_exit
cbnz x0, .Lhandle_close_fail
zircon_syscall ZX_SYS_thread_exit, zx_thread_exit, zx_vmar_unmap_handle_close_thread_exit
// It should be impossible to get here.
brk #1000
pop_regpair x19, x20
brk #1000
syscall_entry_end zx_vmar_unmap_handle_close_thread_exit