Add new rustc target for x86_64 machines that can target the iphonesimulator

compiler/rustc_target/src/spec/apple_sdk_base.rs

@@ -14,14 +14,15 @@ pub enum Arch {
     X86_64,
     X86_64_macabi,
     Arm64_macabi,
+    X86_64_sim,
     Arm64_sim,
 }
 
 fn target_abi(arch: Arch) -> &'static str {
     match arch {
         Armv7 | Armv7k | Armv7s | Arm64 | Arm64_32 | I386 | X86_64 => "",
         X86_64_macabi | Arm64_macabi => "macabi",
-        Arm64_sim => "sim",
+        X86_64_sim | Arm64_sim => "sim",
     }
 }
 
@@ -36,13 +37,14 @@ fn target_cpu(arch: Arch) -> &'static str {
         X86_64 => "core2",
         X86_64_macabi => "core2",
         Arm64_macabi => "apple-a12",
+        X86_64_sim => "core2",
         Arm64_sim => "apple-a12",
     }
 }
 
 fn link_env_remove(arch: Arch) -> Cow<'static, [Cow<'static, str>]> {
     match arch {
-        Armv7 | Armv7k | Armv7s | Arm64 | Arm64_32 | I386 | X86_64 | Arm64_sim => {
+        Armv7 | Armv7k | Armv7s | Arm64 | Arm64_32 | I386 | X86_64 | X86_64_sim | Arm64_sim => {
             cvs!["MACOSX_DEPLOYMENT_TARGET"]
         }
         X86_64_macabi | Arm64_macabi => cvs!["IPHONEOS_DEPLOYMENT_TARGET"],

compiler/rustc_target/src/spec/mod.rs

@@ -926,6 +926,7 @@ supported_targets! {
     ("armv7s-apple-ios", armv7s_apple_ios),
     ("x86_64-apple-ios-macabi", x86_64_apple_ios_macabi),
     ("aarch64-apple-ios-macabi", aarch64_apple_ios_macabi),
+    ("x86_64-apple-ios-sim", x86_64_apple_ios_sim),
     ("aarch64-apple-ios-sim", aarch64_apple_ios_sim),
     ("aarch64-apple-tvos", aarch64_apple_tvos),
     ("x86_64-apple-tvos", x86_64_apple_tvos),

compiler/rustc_target/src/spec/x86_64_apple_ios_sim.rs

@@ -0,0 +1,26 @@
+use super::apple_sdk_base::{opts, Arch};
+use crate::spec::{StackProbeType, Target, TargetOptions};
+
+pub fn target() -> Target {
+    let base = opts("ios", Arch::X86_64_sim);
+
+    // Clang automatically chooses a more specific target based on
+    // IPHONEOS_DEPLOYMENT_TARGET.
+    // This is required for the simulator target to pick the right
+    // MACH-O commands, so we do too.
+    let arch = "x86_64";
+    let llvm_target = super::apple_base::ios_sim_llvm_target(arch);
+
+    Target {
+        llvm_target: llvm_target.into(),
+        pointer_width: 64,
+        data_layout: "e-m:o-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128".into(),
+        arch: "x86_64".into(),
+        options: TargetOptions {
+            max_atomic_width: Some(64),
+            // don't use probe-stack=inline-asm until rust#83139 and rust#84667 are resolved
+            stack_probes: StackProbeType::Call,
+            ..base
+        },
+    }
+}

src/doc/rustc/src/platform-support.md

@@ -124,6 +124,7 @@ target | std | notes
 -------|:---:|-------
 `aarch64-apple-ios` | ✓ | ARM64 iOS
 [`aarch64-apple-ios-sim`](platform-support/aarch64-apple-ios-sim.md) | ✓ | Apple iOS Simulator on ARM64
+`x86_64-apple-ios-sim` | ✓ | Apple iOS Simulator on X86_64
 `aarch64-fuchsia` | ✓ | ARM64 Fuchsia
 `aarch64-linux-android` | ✓ | ARM64 Android
 `aarch64-unknown-none-softfloat` | * | Bare ARM64, softfloat