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-rw-r--r--src/test/assembly/x86_64-naked-fn-no-cet-prolog.rs24
1 files changed, 24 insertions, 0 deletions
diff --git a/src/test/assembly/x86_64-naked-fn-no-cet-prolog.rs b/src/test/assembly/x86_64-naked-fn-no-cet-prolog.rs
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+++ b/src/test/assembly/x86_64-naked-fn-no-cet-prolog.rs
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+// compile-flags: -C no-prepopulate-passes -Zcf-protection=full
+// assembly-output: emit-asm
+// needs-asm-support
+// only-x86_64
+
+#![crate_type = "lib"]
+#![feature(naked_functions)]
+use std::arch::asm;
+
+// The problem at hand: Rust has adopted a fairly strict meaning for "naked functions",
+// meaning "no prologue whatsoever, no, really, not one instruction."
+// Unfortunately, x86's control-flow enforcement, specifically indirect branch protection,
+// works by using an instruction for each possible landing site,
+// and LLVM implements this via making sure of that.
+#[no_mangle]
+#[naked]
+pub unsafe extern "sysv64" fn will_halt() -> ! {
+ // CHECK-NOT: endbr{{32|64}}
+ // CHECK: hlt
+ asm!("hlt", options(noreturn))
+}
+
+// what about aarch64?
+// "branch-protection"=false