From caf2fa30258879006c88398ef4810039ae0e548c Mon Sep 17 00:00:00 2001
From: Takashi Kokubun <takashikkbn@gmail.com>
Date: Mon, 22 Sep 2025 15:29:50 -0700
Subject: [PATCH] ZJIT: Guard receiver class for CCallVariadic

---
 test/ruby/test_zjit.rb |  7 +++++++
 zjit/src/hir.rs        | 13 ++++++++++---
 2 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/test/ruby/test_zjit.rb b/test/ruby/test_zjit.rb
index f0109bda8b147c..c1e8cfa8059f08 100644
--- a/test/ruby/test_zjit.rb
+++ b/test/ruby/test_zjit.rb
@@ -470,6 +470,13 @@ def entry = test(a: 1, b: 2)
     }
   end
 
+  def test_send_ccall_variadic_with_different_receiver_classes
+    assert_compiles '[true, true]', %q{
+      def test(obj) = obj.start_with?("a")
+      [test("abc"), test(:abc)]
+    }, call_threshold: 2
+  end
+
   def test_forwardable_iseq
     assert_compiles '1', %q{
       def test(...) = 1
diff --git a/zjit/src/hir.rs b/zjit/src/hir.rs
index faf363e32a0bc6..136764f137b99b 100644
--- a/zjit/src/hir.rs
+++ b/zjit/src/hir.rs
@@ -2169,6 +2169,11 @@ impl Function {
                             state
                         });
 
+                        if let Some(profiled_type) = profiled_type {
+                            // Guard receiver class
+                            recv = fun.push_insn(block, Insn::GuardType { val: recv, guard_type: Type::from_profiled_type(profiled_type), state });
+                        }
+
                         let cfun = unsafe { get_mct_func(cfunc) }.cast();
                         let ccall = fun.push_insn(block, Insn::CCallVariadic {
                             cfun,
@@ -7131,9 +7136,10 @@ mod opt_tests {
           v4:StringExact[VALUE(0x1000)] = Const Value(VALUE(0x1000))
           v6:StringExact = StringCopy v4
           PatchPoint MethodRedefined(Object@0x1008, puts@0x1010, cme:0x1018)
-          v16:BasicObject = CCallVariadic puts@0x1040, v0, v6
+          v16:HeapObject[class_exact*:Object@VALUE(0x1008)] = GuardType v0, HeapObject[class_exact*:Object@VALUE(0x1008)]
+          v17:BasicObject = CCallVariadic puts@0x1040, v16, v6
           CheckInterrupts
-          Return v16
+          Return v17
         ");
     }
 
@@ -8515,7 +8521,8 @@ mod opt_tests {
           PatchPoint MethodRedefined(Set@0x1008, new@0x1010, cme:0x1018)
           v10:HeapObject = ObjectAlloc v34
           PatchPoint MethodRedefined(Set@0x1008, initialize@0x1040, cme:0x1048)
-          v39:BasicObject = CCallVariadic initialize@0x1070, v10
+          v39:HeapObject[class_exact:Set] = GuardType v10, HeapObject[class_exact:Set]
+          v40:BasicObject = CCallVariadic initialize@0x1070, v39
           CheckInterrupts
           CheckInterrupts
           Return v10