Rollup merge of #128700 - Oneirical:i-ffind-these-tests-quite-simdple, r=jieyouxu

Migrate `simd-ffi` `run-make` test to rmake

Part of #121876 and the associated [Google Summer of Code project](https://blog.rust-lang.org/2024/05/01/gsoc-2024-selected-projects.html).

try-job: x86_64-msvc
try-job: x86_64-mingw
try-job: i686-msvc
try-job: armhf-gnu
try-job: test-various
try-job: aarch64-apple
try-job: x86_64-gnu-llvm-17

Author: tgross35

src/tools/tidy/src/allowed_run_make_makefiles.txt

@@ -26,7 +26,6 @@ run-make/redundant-libs/Makefile
 run-make/remap-path-prefix-dwarf/Makefile
 run-make/reproducible-build/Makefile
 run-make/rlib-format-packed-bundled-libs/Makefile
-run-make/simd-ffi/Makefile
 run-make/split-debuginfo/Makefile
 run-make/staticlib-dylib-linkage/Makefile
 run-make/symbol-mangling-hashed/Makefile

tests/run-make/simd-ffi/Makefile

@@ -0,0 +1,63 @@
+// Using SIMD types in a program with foreign-function interfaces used to result in an ICE
+// (internal compiler error). Since this was fixed in #21233, it should be checked that
+// compilation of SIMD and FFI together should be successful on all the most common
+// architectures.
+// Note that this test does not check linking or binary execution.
+// See https://github.com/rust-lang/rust/pull/21233
+
+use run_make_support::{llvm_components_contain, rustc};
+
+fn main() {
+    let mut targets = Vec::new();
+    // arm-specific targets.
+    if llvm_components_contain("arm") {
+        targets.append(&mut vec![
+            "arm-linux-androideabi".to_owned(),
+            "arm-unknown-linux-gnueabihf".to_owned(),
+            "arm-unknown-linux-gnueabi".to_owned(),
+        ]);
+    }
+    let mut x86_archs = Vec::new();
+    if llvm_components_contain("x86") {
+        x86_archs.append(&mut vec!["i686", "x86_64"]);
+    }
+    // Linux has all x86 targets, plus aarch64 and mips.
+    let mut extra_targets = x86_archs.clone();
+    if llvm_components_contain("aarch64") {
+        extra_targets.push("aarch64");
+    }
+    if llvm_components_contain("mips") {
+        extra_targets.append(&mut vec!["mips", "mipsel"]);
+    }
+
+    for target in extra_targets {
+        let linux = format!("{target}-unknown-linux-gnu");
+        targets.push(linux);
+    }
+
+    // Windows and Darwin (OSX) only receive x86 targets.
+    let extra_targets = x86_archs.clone();
+    for target in extra_targets {
+        let windows = format!("{target}-pc-windows-gnu");
+        let darwin = format!("{target}-apple-darwin");
+        targets.push(windows);
+        targets.push(darwin);
+    }
+
+    for target in targets {
+        // compile the rust file to the given target, but only to asm and IR
+        // form, to avoid having to have an appropriate linker.
+        //
+        // we need some features because the integer SIMD instructions are not
+        // enabled by-default for i686 and ARM; these features will be invalid
+        // on some platforms, but LLVM just prints a warning so that's fine for
+        // now.
+        rustc()
+            .target(&target)
+            .emit("llvm-ir,asm")
+            .input("simd.rs")
+            .arg("-Ctarget-feature=+neon,+sse")
+            .arg(&format!("-Cextra-filename=-{target}"))
+            .run();
+    }
+}