add --yjit-dump-iseqs param (https://github.com/Shopify/ruby/pull/332)

1 files changed, 35 insertions, 0 deletions

diff --git a/yjit/src/utils.rs b/yjit/src/utils.rs
index 02fbce47d8..ade573b8da 100644
--- a/yjit/src/utils.rs
+++ b/yjit/src/utils.rs
@@ -71,6 +71,41 @@ macro_rules! offset_of {
 #[allow(unused)]
 pub(crate) use offset_of;
 
+// Convert a CRuby UTF-8-encoded RSTRING into a Rust string.
+// This should work fine on ASCII strings and anything else
+// that is considered legal UTF-8, including embedded nulls.
+fn ruby_str_to_rust(v: VALUE) -> String {
+    // Make sure the CRuby encoding is UTF-8 compatible
+    let encoding = unsafe { rb_ENCODING_GET(v) } as u32;
+    assert!(encoding == RUBY_ENCINDEX_ASCII_8BIT || encoding == RUBY_ENCINDEX_UTF_8 || encoding == RUBY_ENCINDEX_US_ASCII);
+
+    let str_ptr = unsafe { rb_RSTRING_PTR(v) } as *mut u8;
+    let str_len: usize = unsafe { rb_RSTRING_LEN(v) }.try_into().unwrap();
+    let str_slice: &[u8] = unsafe { slice::from_raw_parts(str_ptr, str_len) };
+    String::from_utf8(str_slice.to_vec()).unwrap() // does utf8 validation
+}
+
+// Location is the file defining the method, colon, method name.
+// Filenames are sometimes internal strings supplied to eval,
+// so be careful with them.
+pub fn iseq_get_location(iseq: IseqPtr) -> String {
+    let iseq_path = unsafe { rb_iseq_path(iseq) };
+    let iseq_method = unsafe { rb_iseq_method_name(iseq) };
+
+    let mut s = if iseq_path == Qnil {
+        "None".to_string()
+    } else {
+        ruby_str_to_rust(iseq_path)
+    };
+    s.push_str(":");
+    if iseq_method == Qnil {
+        s.push_str("None");
+    } else {
+        s.push_str(& ruby_str_to_rust(iseq_method));
+    }
+    s
+}
+
 #[cfg(test)]
 mod tests {
     #[test]