Add Type freezing paper.

Author: Pavel-Durov

softdev.bib

@@ -3333,3 +3333,12 @@ @article{yanovski21ghostcell
   year={2021},
   month = Aug,
 }
+
+@inproceedings{cheng20typefreezing,
+    title = "Type freezing: exploiting attribute type monomorphism in tracing {JIT} compilers",
+    author = "Cheng, Lin and Ilbeyi, Berkin and Bolz-Tereick, Carl Friedrich and Batten, Christopher",
+    year = 2020,
+    isbn = {9781450370479},
+    month = Feb,
+    booktitle = "CGO"
+}