CFI: Enable KCFI testing of run-pass tests

This enables KCFI-based testing for all the CFI run-pass tests in the
suite today. We can add the test header on top of in-flight CFI tests
once they land.

It also enables KCFI as a sanitizer for x86_64 and aarch64 Linux to make
this possible. The sanitizer should likely be available for all aarch64,
x86_64, and riscv targets, but that isn't critical for initial testing.

Author: maurer

compiler/rustc_target/src/spec/targets/aarch64_unknown_linux_gnu.rs

@@ -19,6 +19,7 @@ pub fn target() -> Target {
             stack_probes: StackProbeType::Inline,
             supported_sanitizers: SanitizerSet::ADDRESS
                 | SanitizerSet::CFI
+                | SanitizerSet::KCFI
                 | SanitizerSet::LEAK
                 | SanitizerSet::MEMORY
                 | SanitizerSet::MEMTAG

compiler/rustc_target/src/spec/targets/x86_64_unknown_linux_gnu.rs

@@ -10,6 +10,7 @@ pub fn target() -> Target {
     base.static_position_independent_executables = true;
     base.supported_sanitizers = SanitizerSet::ADDRESS
         | SanitizerSet::CFI
+        | SanitizerSet::KCFI
         | SanitizerSet::DATAFLOW
         | SanitizerSet::LEAK
         | SanitizerSet::MEMORY

src/tools/compiletest/src/header.rs

@@ -826,6 +826,7 @@ const KNOWN_DIRECTIVE_NAMES: &[&str] = &[
     "needs-sanitizer-cfi",
     "needs-sanitizer-dataflow",
     "needs-sanitizer-hwaddress",
+    "needs-sanitizer-kcfi",
     "needs-sanitizer-leak",
     "needs-sanitizer-memory",
     "needs-sanitizer-memtag",

tests/ui/sanitizer/cfi-closure-fn-ptr-cast.rs

@@ -5,11 +5,15 @@
 //
 // This checks that the reified function pointer will have the expected alias set at its call-site.
 
-//@ needs-sanitizer-cfi
+//@ revisions: cfi kcfi
 // FIXME(#122848) Remove only-linux once OSX CFI binaries work
 //@ only-linux
-//@ compile-flags: --crate-type=bin -Cprefer-dynamic=off -Clto -Zsanitizer=cfi
-//@ compile-flags: -C target-feature=-crt-static -C codegen-units=1 -C opt-level=0
+//@ [cfi] needs-sanitizer-cfi
+//@ [kcfi] needs-sanitizer-kcfi
+//@ compile-flags: -C target-feature=-crt-static
+//@ [cfi] compile-flags: -C codegen-units=1 -C lto -C prefer-dynamic=off -C opt-level=0
+//@ [cfi] compile-flags: -Z sanitizer=cfi
+//@ [kcfi] compile-flags: -Z sanitizer=kcfi
 //@ run-pass
 
 pub fn main() {

tests/ui/sanitizer/cfi-complex-receiver.rs

@@ -2,11 +2,15 @@
 // * Arc<dyn Foo> as for custom receivers
 // * &dyn Bar<T=Baz> for type constraints
 
-//@ needs-sanitizer-cfi
+//@ revisions: cfi kcfi
 // FIXME(#122848) Remove only-linux once OSX CFI binaries work
 //@ only-linux
-//@ compile-flags: --crate-type=bin -Cprefer-dynamic=off -Clto -Zsanitizer=cfi
-//@ compile-flags: -C target-feature=-crt-static -C codegen-units=1 -C opt-level=0
+//@ [cfi] needs-sanitizer-cfi
+//@ [kcfi] needs-sanitizer-kcfi
+//@ compile-flags: -C target-feature=-crt-static
+//@ [cfi] compile-flags: -C codegen-units=1 -C lto -C prefer-dynamic=off -C opt-level=0
+//@ [cfi] compile-flags: -Z sanitizer=cfi
+//@ [kcfi] compile-flags: -Z sanitizer=kcfi
 //@ run-pass
 
 use std::sync::Arc;

tests/ui/sanitizer/cfi-self-ref.rs

@@ -1,10 +1,14 @@
 // Check that encoding self-referential types works with #[repr(transparent)]
 
-//@ needs-sanitizer-cfi
+//@ revisions: cfi kcfi
 // FIXME(#122848) Remove only-linux once OSX CFI binaries work
 //@ only-linux
-//@ compile-flags: --crate-type=bin -Cprefer-dynamic=off -Clto -Zsanitizer=cfi
-//@ compile-flags: -C target-feature=-crt-static -C codegen-units=1 -C opt-level=0
+//@ [cfi] needs-sanitizer-cfi
+//@ [kcfi] needs-sanitizer-kcfi
+//@ compile-flags: -C target-feature=-crt-static
+//@ [cfi] compile-flags: -C codegen-units=1 -C lto -C prefer-dynamic=off -C opt-level=0
+//@ [cfi] compile-flags: -Z sanitizer=cfi
+//@ [kcfi] compile-flags: -Z sanitizer=kcfi
 //@ run-pass
 
 use std::marker::PhantomData;

tests/ui/sanitizer/cfi-virtual-auto.rs

@@ -1,10 +1,14 @@
 // Tests that calling a trait object method on a trait object with additional auto traits works.
 
-//@ needs-sanitizer-cfi
+//@ revisions: cfi kcfi
 // FIXME(#122848) Remove only-linux once OSX CFI binaries work
 //@ only-linux
-//@ compile-flags: --crate-type=bin -Cprefer-dynamic=off -Clto -Zsanitizer=cfi
-//@ compile-flags: -C target-feature=-crt-static -C codegen-units=1 -C opt-level=0
+//@ [cfi] needs-sanitizer-cfi
+//@ [kcfi] needs-sanitizer-kcfi
+//@ compile-flags: -C target-feature=-crt-static
+//@ [cfi] compile-flags: -C codegen-units=1 -C lto -C prefer-dynamic=off -C opt-level=0
+//@ [cfi] compile-flags: -Z sanitizer=cfi
+//@ [kcfi] compile-flags: -Z sanitizer=kcfi
 //@ run-pass
 
 trait Foo {