From 898950caf1a7bc9b6c41e74bbfac9591724f307c Mon Sep 17 00:00:00 2001
From: Andre Richter <andre.o.richter@gmail.com>
Date: Thu, 9 Aug 2018 22:04:55 +0200
Subject: [PATCH] targets: aarch64: Add bare-metal aarch64 target

A generic AArch64 target that can be used for writing bare-metal code
for 64-bit ARM architectures.
---
 .../spec/aarch64_unknown_none.rs              | 46 +++++++++++++++++++
 src/librustc_target/spec/mod.rs               |  2 +
 2 files changed, 48 insertions(+)
 create mode 100644 src/librustc_target/spec/aarch64_unknown_none.rs

diff --git a/src/librustc_target/spec/aarch64_unknown_none.rs b/src/librustc_target/spec/aarch64_unknown_none.rs
new file mode 100644
index 0000000000000..cfba0614adcd6
--- /dev/null
+++ b/src/librustc_target/spec/aarch64_unknown_none.rs
@@ -0,0 +1,46 @@
+// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// Generic AArch64 target for bare-metal code
+//
+// Can be used in conjunction with the `target-feature` and
+// `target-cpu` compiler flags to opt-in more hardware-specific
+// features.
+//
+// For example, `-C target-cpu=cortex-a53`.
+
+use super::{LldFlavor, LinkerFlavor, Target, TargetOptions, PanicStrategy};
+
+pub fn target() -> Result<Target, String> {
+    let opts = TargetOptions {
+        linker: Some("rust-lld".to_owned()),
+        executables: true,
+        relocation_model: "static".to_string(),
+        disable_redzone: true,
+        linker_is_gnu: true,
+        max_atomic_width: Some(128),
+        panic_strategy: PanicStrategy::Abort,
+        abi_blacklist: super::arm_base::abi_blacklist(),
+        .. Default::default()
+    };
+    Ok(Target {
+        llvm_target: "aarch64-unknown-none".to_string(),
+        target_endian: "little".to_string(),
+        target_pointer_width: "64".to_string(),
+        target_c_int_width: "32".to_string(),
+        target_os: "none".to_string(),
+        target_env: "".to_string(),
+        target_vendor: "".to_string(),
+        data_layout: "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128".to_string(),
+        arch: "aarch64".to_string(),
+        linker_flavor: LinkerFlavor::Lld(LldFlavor::Ld),
+        options: opts,
+    })
+}
diff --git a/src/librustc_target/spec/mod.rs b/src/librustc_target/spec/mod.rs
index 6faab77d7709f..8fc1f6ac4a581 100644
--- a/src/librustc_target/spec/mod.rs
+++ b/src/librustc_target/spec/mod.rs
@@ -379,6 +379,8 @@ supported_targets! {
     ("x86_64-unknown-hermit", x86_64_unknown_hermit),
 
     ("riscv32imac-unknown-none-elf", riscv32imac_unknown_none_elf),
+
+    ("aarch64-unknown-none", aarch64_unknown_none),
 }
 
 /// Everything `rustc` knows about how to compile for a specific target.