1 files changed, 53 insertions, 0 deletions
diff --git a/examples/dump-bytecode.rs b/examples/dump-bytecode.rs
new file mode 100644
index 0000000..912da41
--- /dev/null
+++ b/examples/dump-bytecode.rs
@@ -0,0 +1,53 @@
+use eyre::{Result, bail};
+use std::io::Read;
+use std::path::Path;
+use tinywasm::parser::Parser;
+use tinywasm::types::{ExternalKind, ImportKind};
+
+fn read_input(path: &str) -> Result<Vec<u8>> {
+    if path == "-" {
+        let mut source = String::new();
+        std::io::stdin().read_to_string(&mut source)?;
+        return Ok(wat::parse_str(source)?);
+    }
+
+    let bytes = std::fs::read(path)?;
+    let is_wasm = Path::new(path).extension().and_then(|s| s.to_str()) == Some("wasm");
+    if is_wasm { Ok(bytes) } else { Ok(wat::parse_bytes(&bytes)?.into_owned()) }
+}
+
+fn main() -> Result<()> {
+    let args = std::env::args().collect::<Vec<_>>();
+    if args.len() != 2 {
+        bail!("usage: cargo run --example dump-bytecode -- <module.wat|module.wasm|->")
+    }
+
+    let wasm = read_input(&args[1])?;
+    let module = Parser::new().parse_module_bytes(&wasm)?;
+
+    let imported_func_count =
+        module.imports.iter().filter(|import| matches!(import.kind, ImportKind::Function(_))).count() as u32;
+
+    for (func_idx, func) in module.funcs.iter().enumerate() {
+        let global_idx = imported_func_count + func_idx as u32;
+        let exports = module
+            .exports
+            .iter()
+            .filter(|export| export.kind == ExternalKind::Func && export.index == global_idx)
+            .map(|export| export.name.as_ref())
+            .collect::<Vec<_>>();
+
+        if exports.is_empty() {
+            println!("func[{func_idx}] global={global_idx}");
+        } else {
+            println!("func[{func_idx}] global={global_idx} exports={exports:?}");
+        }
+
+        for (ip, instr) in func.instructions.iter().enumerate() {
+            println!("  {ip:04}: {instr:?}");
+        }
+        println!();
+    }
+
+    Ok(())
+}