diff --git a/yjit/src/codegen.rs b/yjit/src/codegen.rs
index 6963aca48e..1d9955260b 100644
--- a/yjit/src/codegen.rs
+++ b/yjit/src/codegen.rs
@@ -7095,15 +7095,15 @@ fn gen_send_iseq(
     }
 
     match block_arg_type {
-        Some(Type::Nil) => {
+        Some(BlockArg::Nil) => {
             // We have a nil block arg, so let's pop it off the args
             asm.stack_pop(1);
         }
-        Some(Type::BlockParamProxy) => {
+        Some(BlockArg::BlockParamProxy) => {
             // We don't need the actual stack value
             asm.stack_pop(1);
         }
-        Some(Type::TProc) => {
+        Some(BlockArg::TProc) => {
             // Place the proc as the block handler. We do this early because
             // the block arg being at the top of the stack gets in the way of
             // rest param handling later. Also, since there are C calls that
@@ -7136,7 +7136,6 @@ fn gen_send_iseq(
         None => {
             // Nothing to do
         }
-        _ => unreachable!(),
     }
 
     if kw_splat {
@@ -7396,9 +7395,9 @@ fn gen_send_iseq(
     } else if let Some(captured_opnd) = captured_opnd {
         let ep_opnd = asm.load(Opnd::mem(64, captured_opnd, SIZEOF_VALUE_I32)); // captured->ep
         SpecVal::PrevEPOpnd(ep_opnd)
-    } else if let Some(Type::TProc) = block_arg_type {
+    } else if let Some(BlockArg::TProc) = block_arg_type {
         SpecVal::BlockHandler(Some(BlockHandler::AlreadySet))
-    } else if let Some(Type::BlockParamProxy) = block_arg_type {
+    } else if let Some(BlockArg::BlockParamProxy) = block_arg_type {
         SpecVal::BlockHandler(Some(BlockHandler::BlockParamProxy))
     } else {
         SpecVal::BlockHandler(block)
@@ -7942,12 +7941,22 @@ fn exit_if_has_rest_and_optional_and_block(asm: &mut Assembler, iseq_has_rest: b
     )
 }
 
+#[derive(Clone, Copy)]
+enum BlockArg {
+    Nil,
+    /// A special sentinel value indicating the block parameter should be read from
+    /// the current surrounding cfp
+    BlockParamProxy,
+    /// A proc object. Could be an instance of a subclass of ::rb_cProc
+    TProc,
+}
+
 #[must_use]
 fn exit_if_unsupported_block_arg_type(
     jit: &mut JITState,
     asm: &mut Assembler,
     supplying_block_arg: bool
-) -> Option<Option<Type>> {
+) -> Option<Option<BlockArg>> {
     let block_arg_type = if supplying_block_arg {
         asm.ctx.get_opnd_type(StackOpnd(0))
     } else {
@@ -7956,16 +7965,15 @@ fn exit_if_unsupported_block_arg_type(
     };
 
     match block_arg_type {
-        Type::Nil | Type::BlockParamProxy => {
-            // We'll handle this later
-            Some(Some(block_arg_type))
-        }
+        // We'll handle Nil and BlockParamProxy later
+        Type::Nil => Some(Some(BlockArg::Nil)),
+        Type::BlockParamProxy => Some(Some(BlockArg::BlockParamProxy)),
         _ if {
             let sample_block_arg = jit.peek_at_stack(&asm.ctx, 0);
             unsafe { rb_obj_is_proc(sample_block_arg) }.test()
         } => {
             // Speculate that we'll have a proc as the block arg
-            Some(Some(Type::TProc))
+            Some(Some(BlockArg::TProc))
         }
         _ => {
             gen_counter_incr(asm, Counter::send_iseq_block_arg_type);
diff --git a/yjit/src/core.rs b/yjit/src/core.rs
index 90e6490997..000e0c0be0 100644
--- a/yjit/src/core.rs
+++ b/yjit/src/core.rs
@@ -60,13 +60,11 @@ pub enum Type {
     TArray, // An object with the T_ARRAY flag set, possibly an rb_cArray
     THash, // An object with the T_HASH flag set, possibly an rb_cHash
 
-    TProc, // A proc object. Could be an instance of a subclass of ::rb_cProc
-
     BlockParamProxy, // A special sentinel value indicating the block parameter should be read from
                      // the current surrounding cfp
 
     // The context currently relies on types taking at most 4 bits (max value 15)
-    // to encode, so if we add any more, we will need to refactor the context,
+    // to encode, so if we add two more, we will need to refactor the context,
     // or we could remove HeapSymbol, which is currently unused.
 }
 
@@ -113,8 +111,6 @@ impl Type {
                 RUBY_T_ARRAY => Type::TArray,
                 RUBY_T_HASH => Type::THash,
                 RUBY_T_STRING => Type::TString,
-                #[cfg(not(test))]
-                RUBY_T_DATA if unsafe { rb_obj_is_proc(val).test() } => Type::TProc,
                 _ => Type::UnknownHeap,
             }
         }
@@ -159,7 +155,6 @@ impl Type {
             Type::TString => true,
             Type::CString => true,
             Type::BlockParamProxy => true,
-            Type::TProc => true,
             _ => false,
         }
     }
@@ -195,7 +190,6 @@ impl Type {
             Type::THash => Some(RUBY_T_HASH),
             Type::ImmSymbol | Type::HeapSymbol => Some(RUBY_T_SYMBOL),
             Type::TString | Type::CString => Some(RUBY_T_STRING),
-            Type::TProc => Some(RUBY_T_DATA),
             Type::Unknown | Type::UnknownImm | Type::UnknownHeap => None,
             Type::BlockParamProxy => None,
         }