Given that clasp is a Common Lisp - that passes 97%+ of CL ANSI tests on par with other CL implementations like SBCL - then answer is obviously yes. You need t

Given that clasp is a Common Lisp - that passes 97%+ of CL ANSI tests on par with other CL implementations like SBCL - then answer is obviously yes. You need to go into more detail about why you think llvm would make a difference. Common Lisp is usually compiled to native code and the compiler is - unlike most other languages that compile to native code - exposed and available at runtime. When you program interactively in a natively-compiled Common Lisp implementation like clasp or SBCL or ClozureCL, your code is compiled to native code on the spot. You can even customize the code generation via compiler macros. LLVM is just another compiler backend that can slot in so in that regard, conceptually it's seamless.