From 8aad5f45d57ca5e2e51176c9d6aa22583b6cf91d Mon Sep 17 00:00:00 2001
From: Mike Leany <55358344+mikeleany@users.noreply.github.com>
Date: Fri, 17 Sep 2021 23:03:59 -0600
Subject: [PATCH] Add new target: `x86_64-unknown-none-elf`

---
 compiler/rustc_target/src/spec/mod.rs         |  2 ++
 .../src/spec/x86_64_unknown_none_elf.rs       | 29 +++++++++++++++++++
 2 files changed, 31 insertions(+)
 create mode 100644 compiler/rustc_target/src/spec/x86_64_unknown_none_elf.rs

diff --git a/compiler/rustc_target/src/spec/mod.rs b/compiler/rustc_target/src/spec/mod.rs
index ff5dfa3f746..4b357b3cca1 100644
--- a/compiler/rustc_target/src/spec/mod.rs
+++ b/compiler/rustc_target/src/spec/mod.rs
@@ -954,6 +954,8 @@ fn $module() {
     ("armv6k-nintendo-3ds", armv6k_nintendo_3ds),
 
     ("armv7-unknown-linux-uclibceabihf", armv7_unknown_linux_uclibceabihf),
+
+    ("x86_64-unknown-none-elf", x86_64_unknown_none_elf),
 }
 
 /// Warnings encountered when parsing the target `json`.
diff --git a/compiler/rustc_target/src/spec/x86_64_unknown_none_elf.rs b/compiler/rustc_target/src/spec/x86_64_unknown_none_elf.rs
new file mode 100644
index 00000000000..2086a1a8d5b
--- /dev/null
+++ b/compiler/rustc_target/src/spec/x86_64_unknown_none_elf.rs
@@ -0,0 +1,29 @@
+// Generic AArch64 target for bare-metal code - Floating point disabled
+//
+// 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::{LinkerFlavor, LldFlavor, PanicStrategy, Target, TargetOptions};
+
+pub fn target() -> Target {
+    let opts = TargetOptions {
+        abi: "softfloat".to_string(),
+        linker_flavor: LinkerFlavor::Lld(LldFlavor::Ld),
+        linker: Some("rust-lld".to_owned()),
+        features: "-mmx,-sse,+soft-float".to_string(),
+        executables: true,
+        disable_redzone: true,
+        panic_strategy: PanicStrategy::Abort,
+        ..Default::default()
+    };
+    Target {
+        llvm_target: "x86_64-unknown-none-elf".to_string(),
+        pointer_width: 64,
+        data_layout: "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128".to_string(),
+        arch: "x86_64".to_string(),
+        options: opts,
+    }
+}