[mono][jit] Add some barriers to the delegate invoke code.

Re: dotnet#81123.

Author: vargaz

src/mono/mono/mini/mini-arm64.c

@@ -168,14 +168,16 @@ get_delegate_invoke_impl (gboolean has_target, gboolean param_count, guint32 *co
 	MINI_BEGIN_CODEGEN ();
 
 	if (has_target) {
-		start = code = mono_global_codeman_reserve (12);
+		int size = 16;
+		start = code = mono_global_codeman_reserve (size);
 
 		/* Replace the this argument with the target */
+		arm_dmb (code, ARM_DMB_ISHLD);
 		arm_ldrx (code, ARMREG_IP0, ARMREG_R0, MONO_STRUCT_OFFSET (MonoDelegate, method_ptr));
 		arm_ldrx (code, ARMREG_R0, ARMREG_R0, MONO_STRUCT_OFFSET (MonoDelegate, target));
 		code = mono_arm_emit_brx (code, ARMREG_IP0);
 
-		g_assert ((code - start) <= 12);
+		g_assert ((code - start) <= size);
 	} else {
 		int size, i;
 

src/mono/mono/mini/mini-trampolines.c

@@ -1122,6 +1122,8 @@ mono_delegate_trampoline (host_mgreg_t *regs, guint8 *code, gpointer *arg, guint
 		code = (guint8 *)mini_add_method_trampoline (m, code, mono_method_needs_static_rgctx_invoke (m, FALSE), FALSE);
 	}
 
+	mono_memory_barrier ();
+
 	delegate->invoke_impl = mono_get_addr_from_ftnptr (code);
 	if (enable_caching && !callvirt && tramp_info->method) {
 		tramp_info->method_ptr = delegate->method_ptr;