YJIT: Try cfg!(target_feature = "lse")

configure.ac

@@ -3761,27 +3761,10 @@ AS_CASE(["${YJIT_SUPPORT}"],
     ])
 
     AS_IF([test -n "${CARGO_BUILD_ARGS}"], [
-        AC_CHECK_TOOL(CARGO, [cargo], [no])
-        AS_IF([test x"$CARGO" = "xno"],
-            AC_MSG_ERROR([cargo is required. Installation instructions available at https://www.rust-lang.org/tools/install])
-        ])
-
-        # Insn::IncrCounter uses ldaddal, which works only on ARMv8.1+.
-        AC_CACHE_CHECK(yjit stats are broken, rb_cv_broken_yjit_stats, [
-            AC_RUN_IFELSE(
-                [AC_LANG_PROGRAM([[]], [[
-                    @%:@ifdef __aarch64__
-                        asm volatile(".arch armv8-a+lse\n"
-                                     "ldaddal xzr, xzr, @<:@sp@:>@");
-                    @%:@endif
-                ]])],
-                [rb_cv_broken_yjit_stats=no],
-                [rb_cv_broken_yjit_stats=yes],
-                [rb_cv_broken_yjit_stats=yes]
-            )
-        ])
-        AS_IF([test "$rb_cv_broken_yjit_stats" = yes], [AC_DEFINE(BROKEN_YJIT_STATS, 1)])
-    )
+             AC_CHECK_TOOL(CARGO, [cargo], [no])
+             AS_IF([test x"$CARGO" = "xno"],
+                AC_MSG_ERROR([cargo is required. Installation instructions available at https://www.rust-lang.org/tools/install])
+             ]))
 
     YJIT_LIBS="yjit/target/${rb_rust_target_subdir}/libyjit.a"
     YJIT_OBJ='yjit.$(OBJEXT)'

yjit.c

@@ -998,16 +998,6 @@ rb_yjit_invalidate_all_method_lookup_assumptions(void)
     // method caches, so we do nothing here for now.
 }
 
-bool
-rb_yjit_stats_supported(void)
-{
-#if defined(BROKEN_YJIT_STATS)
-    return false;
-#else
-    return true;
-#endif
-}
-
 // Primitives used by yjit.rb
 VALUE rb_yjit_stats_enabled_p(rb_execution_context_t *ec, VALUE self);
 VALUE rb_yjit_trace_exit_locations_enabled_p(rb_execution_context_t *ec, VALUE self);

yjit/bindgen/src/main.rs

@@ -275,7 +275,6 @@ fn main() {
         .allowlist_function("rb_ENCODING_GET")
         .allowlist_function("rb_yjit_exit_locations_dict")
         .allowlist_function("rb_yjit_icache_invalidate")
-        .allowlist_function("rb_yjit_stats_supported")
 
         // from vm_sync.h
         .allowlist_function("rb_vm_barrier")

yjit/src/cruby_bindings.inc.rs

@@ -1296,6 +1296,3 @@ extern "C" {
         line: ::std::os::raw::c_int,
     );
 }
-extern "C" {
-    pub fn rb_yjit_stats_supported() -> bool;
-}

yjit/src/options.rs

@@ -1,5 +1,4 @@
 use std::ffi::CStr;
-use crate::cruby::rb_yjit_stats_supported;
 
 // Command-line options
 #[derive(Clone, PartialEq, Eq, Debug)]
@@ -154,7 +153,7 @@ pub fn parse_option(str_ptr: *const std::os::raw::c_char) -> Option<()> {
         ("no-type-prop", "") => unsafe { OPTIONS.no_type_prop = true },
 
         ("stats", "") => {
-            if unsafe { !rb_yjit_stats_supported() } {
+            if cfg!(target_arch = "aarch64") && !cfg!(target_feature = "lse") {
                 eprintln!("Your processor does not support --yjit-stats. Aborting.");
                 std::process::exit(1);
             }