Promote aarch64-apple-darwin to Tier 1

Per rust-lang/rfcs#3671.

Author: evieluvsrainbows

src/bootstrap/src/core/build_steps/llvm.rs

@@ -194,6 +194,7 @@ pub(crate) fn is_ci_llvm_available(config: &Config, asserts: bool) -> bool {
     let supported_platforms = [
         // tier 1
         ("aarch64-unknown-linux-gnu", false),
+        ("aarch64-apple-darwin", false),
         ("i686-pc-windows-gnu", false),
         ("i686-pc-windows-msvc", false),
         ("i686-unknown-linux-gnu", false),
@@ -202,7 +203,6 @@ pub(crate) fn is_ci_llvm_available(config: &Config, asserts: bool) -> bool {
         ("x86_64-pc-windows-gnu", true),
         ("x86_64-pc-windows-msvc", true),
         // tier 2 with host tools
-        ("aarch64-apple-darwin", false),
         ("aarch64-pc-windows-msvc", false),
         ("aarch64-unknown-linux-musl", false),
         ("arm-unknown-linux-gnueabi", false),

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

@@ -33,6 +33,7 @@ All tier 1 targets with host tools support the full standard library.
 target | notes
 -------|-------
 `aarch64-unknown-linux-gnu` | ARM64 Linux (kernel 4.1, glibc 2.17+)
+[`aarch64-apple-darwin`](platform-support/apple-darwin.md) | ARM64 macOS (11.0+, Big Sur+)
 `i686-pc-windows-gnu` | 32-bit MinGW (Windows 10+, Windows Server 2016+) [^x86_32-floats-return-ABI]
 `i686-pc-windows-msvc` | 32-bit MSVC (Windows 10+, Windows Server 2016+) [^x86_32-floats-return-ABI]
 `i686-unknown-linux-gnu` | 32-bit Linux (kernel 3.2+, glibc 2.17+) [^x86_32-floats-return-ABI]
@@ -86,7 +87,6 @@ so Rustup may install the documentation for a similar tier 1 target instead.
 
 target | notes
 -------|-------
-[`aarch64-apple-darwin`](platform-support/apple-darwin.md) | ARM64 macOS (11.0+, Big Sur+)
 `aarch64-pc-windows-msvc` | ARM64 Windows MSVC
 `aarch64-unknown-linux-musl` | ARM64 Linux with musl 1.2.3
 `arm-unknown-linux-gnueabi` | Armv6 Linux (kernel 3.2, glibc 2.17)

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

@@ -5,9 +5,6 @@ Apple macOS targets.
 **Tier: 1**
 
 - `x86_64-apple-darwin`: macOS on 64-bit x86.
-
-**Tier: 2 (with Host Tools)**
-
 - `aarch64-apple-darwin`: macOS on ARM64 (M1-family or later Apple Silicon CPUs).
 
 ## Target maintainers

src/tools/miri/README.md

@@ -212,7 +212,6 @@ degree documented below):
 - All Rust [Tier 1 targets](https://doc.rust-lang.org/rustc/platform-support.html) are supported by
   Miri. They are all checked on Miri's CI, and some (at least one per OS) are even checked on every
   Rust PR, so the shipped Miri should always work on these targets.
-- `aarch64-apple-darwin` is supported.
 - `s390x-unknown-linux-gnu` is supported as our "big-endian target of choice".
 - For every other target with OS `linux`, `macos`, or `windows`, Miri should generally work, but we
   make no promises and we don't run tests for such targets.

src/tools/miri/ci/ci.sh

@@ -137,7 +137,7 @@ case $HOST_TARGET in
     MANY_SEEDS=16 TEST_TARGET=x86_64-pc-windows-gnu run_tests
     ;;
   aarch64-apple-darwin)
-    # Host (tier 2)
+    # Host
     GC_STRESS=1 MIR_OPT=1 MANY_SEEDS=64 TEST_BENCH=1 CARGO_MIRI_ENV=1 run_tests
     # Extra tier 1
     MANY_SEEDS=64 TEST_TARGET=i686-pc-windows-gnu run_tests