ZJIT: Resolve alias in reduce_send_to_ccall (#15947)

Just minor fix to resolve aliases in `reduce_send_to_ccall`.

2 files changed, 38 insertions, 3 deletions

diff --git a/zjit/src/hir.rs b/zjit/src/hir.rs
index 18649b9800..2aa74dce8b 100644
--- a/zjit/src/hir.rs
+++ b/zjit/src/hir.rs
@@ -3782,15 +3782,18 @@ impl Function {
             };
 
             // Do method lookup
-            let cme: *const rb_callable_method_entry_struct = unsafe { rb_callable_method_entry(recv_class, method_id) };
+            let mut cme: *const rb_callable_method_entry_struct = unsafe { rb_callable_method_entry(recv_class, method_id) };
             if cme.is_null() {
                 fun.set_dynamic_send_reason(send_insn_id, SendNotOptimizedMethodType(MethodType::Null));
                 return Err(());
             }
 
             // Filter for C methods
-            // TODO(max): Handle VM_METHOD_TYPE_ALIAS
-            let def_type = unsafe { get_cme_def_type(cme) };
+            let mut def_type = unsafe { get_cme_def_type(cme) };
+            while def_type == VM_METHOD_TYPE_ALIAS {
+                cme = unsafe { rb_aliased_callable_method_entry(cme) };
+                def_type = unsafe { get_cme_def_type(cme) };
+            }
             if def_type != VM_METHOD_TYPE_CFUNC {
                 return Err(());
             }
diff --git a/zjit/src/hir/opt_tests.rs b/zjit/src/hir/opt_tests.rs
index dcfcc1e136..0110af3f2c 100644
--- a/zjit/src/hir/opt_tests.rs
+++ b/zjit/src/hir/opt_tests.rs
@@ -832,6 +832,38 @@ mod hir_opt_tests {
     }
 
     #[test]
+    fn test_optimize_send_to_aliased_cfunc_from_module() {
+        eval("
+            class C
+              include Enumerable
+              def each; yield 1; end
+              alias bar map
+            end
+            def test(o) = o.bar { |x| x }
+            test C.new; test C.new
+        ");
+        assert_snapshot!(hir_string("test"), @r"
+        fn test@<compiled>:7:
+        bb0():
+          EntryPoint interpreter
+          v1:BasicObject = LoadSelf
+          v2:BasicObject = GetLocal :o, l0, SP@4
+          Jump bb2(v1, v2)
+        bb1(v5:BasicObject, v6:BasicObject):
+          EntryPoint JIT(0)
+          Jump bb2(v5, v6)
+        bb2(v8:BasicObject, v9:BasicObject):
+          PatchPoint NoSingletonClass(C@0x1000)
+          PatchPoint MethodRedefined(C@0x1000, bar@0x1008, cme:0x1010)
+          v23:HeapObject[class_exact:C] = GuardType v9, HeapObject[class_exact:C]
+          v24:BasicObject = CCallWithFrame v23, :Enumerable#bar@0x1038, block=0x1040
+          v15:BasicObject = GetLocal :o, l0, EP@3
+          CheckInterrupts
+          Return v24
+        ");
+    }
+
+    #[test]
     fn test_optimize_nonexistent_top_level_call() {
         eval("
             def foo