Added tvOS as a backend

Author: simlay

src/librustc_target/spec/aarch64_apple_tvos.rs

@@ -0,0 +1,25 @@
+use super::apple_tvos_base::{opts, Arch};
+use crate::spec::{LinkerFlavor, Target, TargetOptions, TargetResult};
+
+pub fn target() -> TargetResult {
+    let base = opts(Arch::Arm64)?;
+    Ok(Target {
+        llvm_target: "arm64-apple-tvos".to_string(),
+        target_endian: "little".to_string(),
+        target_pointer_width: "64".to_string(),
+        target_c_int_width: "32".to_string(),
+        data_layout: "e-m:o-i64:64-i128:128-n32:64-S128".to_string(),
+        arch: "aarch64".to_string(),
+        target_os: "tvos".to_string(),
+        target_env: String::new(),
+        target_vendor: "apple".to_string(),
+        linker_flavor: LinkerFlavor::Gcc,
+        options: TargetOptions {
+            features: "+neon,+fp-armv8,+cyclone".to_string(),
+            eliminate_frame_pointer: false,
+            max_atomic_width: Some(128),
+            abi_blacklist: super::arm_base::abi_blacklist(),
+            ..base
+        },
+    })
+}

src/librustc_target/spec/apple_tvos_base.rs

@@ -0,0 +1,123 @@
+use crate::spec::{LinkArgs, LinkerFlavor, TargetOptions};
+use std::env;
+use std::io;
+use std::path::Path;
+use std::process::Command;
+
+use Arch::*;
+
+#[allow(non_camel_case_types)]
+#[derive(Copy, Clone)]
+pub enum Arch {
+    Arm64,
+    X86_64,
+}
+
+impl Arch {
+    pub fn to_string(self) -> &'static str {
+        match self {
+            Arm64 => "arm64",
+            X86_64 => "x86_64",
+        }
+    }
+}
+
+pub fn get_sdk_root(sdk_name: &str) -> Result<String, String> {
+    // Following what clang does
+    // (https://github.com/llvm/llvm-project/blob/
+    // 296a80102a9b72c3eda80558fb78a3ed8849b341/clang/lib/Driver/ToolChains/Darwin.cpp#L1661-L1678)
+    // to allow the SDK path to be set. (For clang, xcrun sets
+    // SDKROOT; for rustc, the user or build system can set it, or we
+    // can fall back to checking for xcrun on PATH.)
+    if let Some(sdkroot) = env::var("SDKROOT").ok() {
+        let p = Path::new(&sdkroot);
+        match sdk_name {
+            // Ignore `SDKROOT` if it's clearly set for the wrong platform.
+            "appletvos"
+                if sdkroot.contains("TVSimulator.platform")
+                    || sdkroot.contains("MacOSX.platform") =>
+            {
+                ()
+            }
+            "appletvsimulator"
+                if sdkroot.contains("TVOS.platform") || sdkroot.contains("MacOSX.platform") =>
+            {
+                ()
+            }
+            // Ignore `SDKROOT` if it's not a valid path.
+            _ if !p.is_absolute() || p == Path::new("/") || !p.exists() => (),
+            _ => return Ok(sdkroot),
+        }
+    }
+    let res =
+        Command::new("xcrun").arg("--show-sdk-path").arg("-sdk").arg(sdk_name).output().and_then(
+            |output| {
+                if output.status.success() {
+                    Ok(String::from_utf8(output.stdout).unwrap())
+                } else {
+                    let error = String::from_utf8(output.stderr);
+                    let error = format!("process exit with error: {}", error.unwrap());
+                    Err(io::Error::new(io::ErrorKind::Other, &error[..]))
+                }
+            },
+        );
+
+    match res {
+        Ok(output) => Ok(output.trim().to_string()),
+        Err(e) => Err(format!("failed to get {} SDK path: {}", sdk_name, e)),
+    }
+}
+
+fn build_pre_link_args(arch: Arch) -> Result<LinkArgs, String> {
+    let sdk_name = match arch {
+        Arm64 => "appletvos",
+        X86_64 => "appletvsimulator",
+    };
+
+    let arch_name = arch.to_string();
+
+    let sdk_root = get_sdk_root(sdk_name)?;
+
+    let mut args = LinkArgs::new();
+    args.insert(
+        LinkerFlavor::Gcc,
+        vec![
+            "-arch".to_string(),
+            arch_name.to_string(),
+            "-isysroot".to_string(),
+            sdk_root.clone(),
+            "-Wl,-syslibroot".to_string(),
+            sdk_root,
+        ],
+    );
+
+    Ok(args)
+}
+
+fn target_cpu(arch: Arch) -> String {
+    match arch {
+        Arm64 => "cyclone",
+        X86_64 => "core2",
+    }
+    .to_string()
+}
+
+fn link_env_remove(arch: Arch) -> Vec<String> {
+    match arch {
+        Arm64 | X86_64 => vec!["MACOSX_DEPLOYMENT_TARGET".to_string()],
+    }
+}
+
+pub fn opts(arch: Arch) -> Result<TargetOptions, String> {
+    let pre_link_args = build_pre_link_args(arch)?;
+    Ok(TargetOptions {
+        cpu: target_cpu(arch),
+        dynamic_linking: false,
+        executables: true,
+        pre_link_args,
+        link_env_remove: link_env_remove(arch),
+        has_elf_tls: false,
+        eliminate_frame_pointer: false,
+        ..super::apple_base::opts()
+    })
+}

src/librustc_target/spec/mod.rs

@@ -48,6 +48,7 @@ pub mod abi;
 mod android_base;
 mod apple_base;
 mod apple_ios_base;
+mod apple_tvos_base;
 mod arm_base;
 mod cloudabi_base;
 mod dragonfly_base;
@@ -434,6 +435,8 @@ supported_targets! {
     ("armv7-apple-ios", armv7_apple_ios),
     ("armv7s-apple-ios", armv7s_apple_ios),
     ("x86_64-apple-ios-macabi", x86_64_apple_ios_macabi),
+    ("aarch64-apple-tvos", aarch64_apple_tvos),
+    ("x86_64-apple-tvos", x86_64_apple_tvos),
 
     ("armebv7r-none-eabi", armebv7r_none_eabi),
     ("armebv7r-none-eabihf", armebv7r_none_eabihf),

src/librustc_target/spec/x86_64_apple_tvos.rs

@@ -0,0 +1,19 @@
+use super::apple_tvos_base::{opts, Arch};
+use crate::spec::{LinkerFlavor, Target, TargetOptions, TargetResult};
+
+pub fn target() -> TargetResult {
+    let base = opts(Arch::X86_64)?;
+    Ok(Target {
+        llvm_target: "x86_64-apple-tvos".to_string(),
+        target_endian: "little".to_string(),
+        target_pointer_width: "64".to_string(),
+        target_c_int_width: "32".to_string(),
+        data_layout: "e-m:o-i64:64-f80:128-n8:16:32:64-S128".to_string(),
+        arch: "x86_64".to_string(),
+        target_os: "tvos".to_string(),
+        target_env: String::new(),
+        target_vendor: "apple".to_string(),
+        linker_flavor: LinkerFlavor::Gcc,
+        options: TargetOptions { max_atomic_width: Some(64), stack_probes: true, ..base },
+    })
+}