1 files changed, 13 insertions, 1 deletions
diff --git a/zjit/src/asm/mod.rs b/zjit/src/asm/mod.rs
index a7f2705af1..0b571f9aff 100644
--- a/zjit/src/asm/mod.rs
+++ b/zjit/src/asm/mod.rs
@@ -1,5 +1,5 @@
 use std::collections::BTreeMap;
-//use std::fmt;
+use std::fmt;
 use std::rc::Rc;
 use std::cell::RefCell;
 use std::mem;
@@ -260,6 +260,18 @@ impl CodeBlock {
     }
 }
 
+/// Produce hex string output from the bytes in a code block
+impl fmt::LowerHex for CodeBlock {
+    fn fmt(&self, fmtr: &mut fmt::Formatter) -> fmt::Result {
+        for pos in 0..self.write_pos {
+            let mem_block = &*self.mem_block.borrow();
+            let byte = unsafe { mem_block.start_ptr().raw_ptr(mem_block).add(pos).read() };
+            fmtr.write_fmt(format_args!("{:02x}", byte))?;
+        }
+        Ok(())
+    }
+}
+
 #[cfg(test)]
 impl CodeBlock {
     /// Stubbed CodeBlock for testing. Can't execute generated code.