1 files changed, 55 insertions, 0 deletions
diff --git a/library/stdarch/crates/stdarch-test/src/wasm.rs b/library/stdarch/crates/stdarch-test/src/wasm.rs
new file mode 100644
index 00000000000..bf411c12148
--- /dev/null
+++ b/library/stdarch/crates/stdarch-test/src/wasm.rs
@@ -0,0 +1,55 @@
+//! Disassembly calling function for `wasm32` targets.
+
+use crate::Function;
+use std::collections::HashSet;
+
+pub(crate) fn disassemble_myself() -> HashSet<Function> {
+    // Use `std::env::args` to find the path to our executable. Assume the
+    // environment is configured such that we can read that file. Read it and
+    // use the `wasmprinter` crate to transform the binary to text, then search
+    // the text for appropriately named functions.
+    let me = std::env::args()
+        .next()
+        .expect("failed to find current wasm file");
+    let output = wasmprinter::print_file(&me).unwrap();
+
+    let mut ret: HashSet<Function> = HashSet::new();
+    let mut lines = output.lines().map(|s| s.trim());
+    while let Some(line) = lines.next() {
+        // If this isn't a function, we don't care about it.
+        if !line.starts_with("(func ") {
+            continue;
+        }
+
+        let mut function = Function {
+            name: String::new(),
+            instrs: Vec::new(),
+        };
+
+        // Empty functions will end in `))` so there's nothing to do, otherwise
+        // we'll have a bunch of following lines which are instructions.
+        //
+        // Lines that have an imbalanced `)` mark the end of a function.
+        if !line.ends_with("))") {
+            while let Some(line) = lines.next() {
+                function.instrs.push(line.to_string());
+                if !line.starts_with("(") && line.ends_with(")") {
+                    break;
+                }
+            }
+        }
+        // The second element here split on whitespace should be the name of
+        // the function, skipping the type/params/results
+        function.name = line.split_whitespace().nth(1).unwrap().to_string();
+        if function.name.starts_with("$") {
+            function.name = function.name[1..].to_string()
+        }
+
+        if !function.name.contains("stdarch_test_shim") {
+            continue;
+        }
+
+        assert!(ret.insert(function));
+    }
+    return ret;
+}