Lower Arm64Call relocations in cranelift-object

[bjorn3]

At least TLS support and better 128bit int support will also be necessary for cg_clif to work on AArch64.

Depends on gimli-rs/object#322

[bjorn3]

The mini_core_hello_world example runs with this PR in combination with the following patch:

diff --git a/example/mini_core.rs b/example/mini_core.rs
index c4834c80..aeec532d 100644
--- a/example/mini_core.rs
+++ b/example/mini_core.rs
@@ -285,9 +285,11 @@ fn ne(&self, other: &u64) -> bool {
 }
 
 impl PartialEq for u128 {
+    #[inline]
     fn eq(&self, other: &u128) -> bool {
         (*self) == (*other)
     }
+    #[inline]
     fn ne(&self, other: &u128) -> bool {
         (*self) != (*other)
     }
@@ -620,11 +622,3 @@ struct PanicLocation {
     column: u32,
 }
 
-#[no_mangle]
-#[cfg(not(windows))]
-pub fn get_tls() -> u8 {
-    #[thread_local]
-    static A: u8 = 42;
-
-    A
-}
diff --git a/example/mini_core_hello_world.rs b/example/mini_core_hello_world.rs
index 6570f2bf..895f6a2e 100644
--- a/example/mini_core_hello_world.rs
+++ b/example/mini_core_hello_world.rs
@@ -287,37 +287,12 @@ struct ExternTypeWrapper {
     assert_eq!(repeat[0], Some(42));
     assert_eq!(repeat[1], Some(42));
 
-    from_decimal_string();
-
-    #[cfg(not(any(jit, windows)))]
-    test_tls();
-
-    #[cfg(all(not(jit), target_os = "linux"))]
-    unsafe {
-        global_asm_test();
-    }
-
     // Both statics have a reference that points to the same anonymous allocation.
     static REF1: &u8 = &42;
     static REF2: &u8 = REF1;
     assert_eq!(*REF1, *REF2);
 }
 
-#[cfg(all(not(jit), target_os = "linux"))]
-extern "C" {
-    fn global_asm_test();
-}
-
-#[cfg(all(not(jit), target_os = "linux"))]
-global_asm! {
-    "
-    .global global_asm_test
-    global_asm_test:
-    // comment that would normally be removed by LLVM
-    ret
-    "
-}
-
 #[repr(C)]
 enum c_void {
     _1,
diff --git a/src/lib.rs b/src/lib.rs
index cfc5902c..c154fde3 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -288,7 +288,7 @@ fn build_isa(sess: &Session, backend_config: &BackendConfig) -> Box<dyn isa::Tar
                 cranelift_codegen::isa::lookup_variant(target_triple, variant).unwrap();
             // Don't use "haswell" as the default, as it implies `has_lzcnt`.
             // macOS CI is still at Ivy Bridge EP, so `lzcnt` is interpreted as `bsr`.
-            builder.enable("nehalem").unwrap();
+            //builder.enable("nehalem").unwrap();
             builder
         }
     };

[cfallin]

Thanks!

[cfallin]

CI failures are curious -- the particular relocation enum value seems to be missing in some builds. Old pinned version, or Cargo feature dependency maybe?

[bjorn3]

The CI failure is because gimli-rs/object#322 needs to be merged first.

[cfallin]

Ah, sorry, missed that it was still pending. Thanks!

[bjorn3]

Object released a new version with the change. CI passed.