From adf29c9a986cb3510b9ddd55e0738b18076f41ad Mon Sep 17 00:00:00 2001
From: Maxime Chevalier-Boisvert <maxime.chevalierboisvert@shopify.com>
Date: Mon, 29 Jan 2024 10:36:34 -0500
Subject: [PATCH] YJIT: add asm comment when we clear local types (#9713)

Small PR to add a comment when we clear local variable types,
so we can be aware that it's happening when looking at the disasm.
---
 yjit/src/backend/ir.rs |  7 +++++++
 yjit/src/codegen.rs    | 10 +++++-----
 2 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/yjit/src/backend/ir.rs b/yjit/src/backend/ir.rs
index 303026d830..3dae4b6f7c 100644
--- a/yjit/src/backend/ir.rs
+++ b/yjit/src/backend/ir.rs
@@ -1173,6 +1173,13 @@ impl Assembler
         }
     }
 
+    /// Erase local variable type information
+    /// eg: because of a call we can't track
+    pub fn clear_local_types(&mut self) {
+        asm_comment!(self, "clear local variable types");
+        self.ctx.clear_local_types();
+    }
+
     /// Spill all live stack temps from registers to the stack
     pub fn spill_temps(&mut self) {
         // Forget registers above the stack top
diff --git a/yjit/src/codegen.rs b/yjit/src/codegen.rs
index a8c77b8d01..cb979b247b 100644
--- a/yjit/src/codegen.rs
+++ b/yjit/src/codegen.rs
@@ -356,7 +356,7 @@ fn jit_prepare_routine_call(
 
     // In case the routine calls Ruby methods, it can set local variables
     // through Kernel#binding and other means.
-    asm.ctx.clear_local_types();
+    asm.clear_local_types();
 }
 
 /// Record the current codeblock write position for rewriting into a jump into
@@ -5892,7 +5892,7 @@ fn gen_send_cfunc(
     asm.store(ec_cfp_opnd, CFP);
 
     // cfunc calls may corrupt types
-    asm.ctx.clear_local_types();
+    asm.clear_local_types();
 
     // Note: the return block of gen_send_iseq() has ctx->sp_offset == 1
     // which allows for sharing the same successor.
@@ -6951,7 +6951,7 @@ fn gen_send_iseq(
     callee_ctx.upgrade_opnd_type(SelfOpnd, recv_type);
 
     // The callee might change locals through Kernel#binding and other means.
-    asm.ctx.clear_local_types();
+    asm.clear_local_types();
 
     // Pop arguments and receiver in return context and
     // mark it as a continuation of gen_leave()
@@ -8012,7 +8012,7 @@ fn gen_invokeblock_specialized(
         asm.mov(stack_ret, ret);
 
         // cfunc calls may corrupt types
-        asm.ctx.clear_local_types();
+        asm.clear_local_types();
 
         // Share the successor with other chains
         jump_to_next_insn(jit, asm, ocb);
@@ -8170,7 +8170,7 @@ fn gen_invokesuper_specialized(
     jit.assume_method_lookup_stable(asm, ocb, cme);
 
     // Method calls may corrupt types
-    asm.ctx.clear_local_types();
+    asm.clear_local_types();
 
     match cme_def_type {
         VM_METHOD_TYPE_ISEQ => {