add test for symbol visibility of #[naked] functions

Author: folkertdev

tests/run-make/naked-symbol-visibility/a_rust_dylib.rs

@@ -0,0 +1,74 @@
+#![feature(naked_functions, asm_const, linkage)]
+#![crate_type = "dylib"]
+
+use std::arch::asm;
+
+pub trait TraitWithConst {
+    const COUNT: u32;
+}
+
+struct Test;
+
+impl TraitWithConst for Test {
+    const COUNT: u32 = 1;
+}
+
+#[no_mangle]
+fn entry() {
+    private_vanilla_rust_function_from_rust_dylib();
+    private_naked_rust_function_from_rust_dylib();
+
+    public_vanilla_generic_function_from_rust_dylib::<Test>();
+    public_naked_generic_function_from_rust_dylib::<Test>();
+}
+
+extern "C" fn private_vanilla_rust_function_from_rust_dylib() -> u32 {
+    42
+}
+
+#[no_mangle]
+pub extern "C" fn public_vanilla_rust_function_from_rust_dylib() -> u32 {
+    42
+}
+
+pub extern "C" fn public_vanilla_generic_function_from_rust_dylib<T: TraitWithConst>() -> u32 {
+    T::COUNT
+}
+
+#[linkage = "weak"]
+extern "C" fn vanilla_weak_linkage() -> u32 {
+    42
+}
+
+#[linkage = "external"]
+extern "C" fn vanilla_external_linkage() -> u32 {
+    42
+}
+
+#[naked]
+extern "C" fn private_naked_rust_function_from_rust_dylib() -> u32 {
+    unsafe { asm!("mov rax, 42", "ret", options(noreturn)) }
+}
+
+#[naked]
+#[no_mangle]
+pub extern "C" fn public_naked_rust_function_from_rust_dylib() -> u32 {
+    unsafe { asm!("mov rax, 42", "ret", options(noreturn)) }
+}
+
+#[naked]
+pub extern "C" fn public_naked_generic_function_from_rust_dylib<T: TraitWithConst>() -> u32 {
+    unsafe { asm!("mov rax, {}", "ret", const T::COUNT, options(noreturn)) }
+}
+
+#[naked]
+#[linkage = "weak"]
+extern "C" fn naked_weak_linkage() -> u32 {
+    unsafe { asm!("mov rax, 42", "ret", options(noreturn)) }
+}
+
+#[naked]
+#[linkage = "external"]
+extern "C" fn naked_external_linkage() -> u32 {
+    unsafe { asm!("mov rax, 42", "ret", options(noreturn)) }
+}

tests/run-make/naked-symbol-visibility/rmake.rs

@@ -0,0 +1,63 @@
+// @only-x86_64
+use run_make_support::{dynamic_lib_name, llvm_readobj, regex, rustc};
+
+fn main() {
+    let rdylib_name = dynamic_lib_name("a_rust_dylib");
+    rustc().arg("-Zshare-generics=no").input("a_rust_dylib.rs").run();
+
+    // check vanilla symbols
+    not_exported(&rdylib_name, "private_vanilla_rust_function_from_rust_dylib");
+    global_function(&rdylib_name, "public_vanilla_rust_function_from_rust_dylib");
+    not_exported(&rdylib_name, "public_vanilla_generic_function_from_rust_dylib");
+
+    weak_function(&rdylib_name, "vanilla_weak_linkage");
+    global_function(&rdylib_name, "vanilla_external_linkage");
+
+    // naked should mirror vanilla
+    not_exported(&rdylib_name, "private_naked_rust_function_from_rust_dylib");
+    global_function(&rdylib_name, "public_naked_rust_function_from_rust_dylib");
+    not_exported(&rdylib_name, "public_naked_generic_function_from_rust_dylib");
+
+    weak_function(&rdylib_name, "naked_weak_linkage");
+    global_function(&rdylib_name, "naked_external_linkage");
+
+    // share generics should expose the generic functions
+    rustc().arg("-Zshare-generics=yes").input("a_rust_dylib.rs").run();
+    global_function(&rdylib_name, "public_vanilla_generic_function_from_rust_dylib");
+    global_function(&rdylib_name, "public_naked_generic_function_from_rust_dylib");
+}
+
+#[track_caller]
+fn global_function(path: &str, symbol_name: &str) {
+    let lines = find_dynamic_symbol(path, symbol_name);
+    let [line] = lines.as_slice() else {
+        panic!("symbol {symbol_name} occurs {} times", lines.len())
+    };
+
+    assert!(line.contains("FUNC"), "`{symbol_name}` is not a function");
+    assert!(line.contains("GLOBAL"), "`{symbol_name}` is not marked as global");
+}
+
+#[track_caller]
+fn weak_function(path: &str, symbol_name: &str) {
+    let lines = find_dynamic_symbol(path, symbol_name);
+    let [line] = lines.as_slice() else {
+        panic!("symbol {symbol_name} occurs {} times", lines.len())
+    };
+
+    assert!(line.contains("FUNC"), "`{symbol_name}` is not a function");
+    assert!(line.contains("WEAK"), "`{symbol_name}` is not marked as weak");
+}
+
+#[track_caller]
+fn not_exported(path: &str, symbol_name: &str) {
+    assert_eq!(find_dynamic_symbol(path, symbol_name).len(), 0)
+}
+
+fn find_dynamic_symbol<'a>(path: &str, symbol_name: &str) -> Vec<String> {
+    let out = llvm_readobj().arg("--dyn-symbols").input(path).run().stdout_utf8();
+    out.lines()
+        .filter(|&line| !line.contains("__imp_") && line.contains(symbol_name))
+        .map(|line| line.to_string())
+        .collect()
+}