refactor(tvix/eval): enhance debug output for bytecode dumps

This adds addresses of thunk and closure chunks to the debug output
displayed when dumping bytecode.

This makes it possible to see in the dump which thunks are referenced
by constants in other thunks.

Change-Id: I2c98de5227e7cb415666cd3134c947a56979dc80
Reviewed-on: https://cl.tvl.fyi/c/depot/+/8137
Autosubmit: tazjin <tazjin@tvl.su>
Reviewed-by: flokli <flokli@flokli.de>
Tested-by: BuildkiteCI

tvix/eval/src/chunk.rs

@@ -143,7 +143,15 @@ impl Chunk {
         }
 
         match self[idx] {
-            OpCode::OpConstant(idx) => writeln!(writer, "OpConstant({}@{})", self[idx], idx.0),
+            OpCode::OpConstant(idx) => {
+                let val_str = match &self[idx] {
+                    Value::Thunk(t) => t.debug_repr(),
+                    Value::Closure(c) => format!("closure({:p})", c.lambda),
+                    val => format!("{}", val),
+                };
+
+                writeln!(writer, "OpConstant({}@{})", val_str, idx.0)
+            }
             op => writeln!(writer, "{:?}", op),
         }?;