Many language theoreticians have taken great efforts in designing higher-level programming languages that are more elegant and more expressive than conventional languages. However, few of these new languages have been implemented very efficiently. The result is that most software engineers still prefer to use conventional languages, even though the new higherlevel languages offer a better and simpler programming model. This dissertation concentrates on improving the performance of programs written in Standard ML (SML)---a statically typed functional language---on today's RISC machines. SML poses tough challenges to efficient implementations: very frequent function calls, polymorphic types, recursive data structures, higher-order functions, and first-class continuations. This dissertation presents the design and evaluation of several new compilation techniques that meet these challenges by taking advantage of some of the higher-level language features in SML. Type-directed compilation ...

. Inline function expansion is an optimization that may improve program performance by removing calling sequences and enlarging the scope of other optimizations. Unfortunately it also has the drawback of enlarging programs. This might impair executable programs performance. In order to get rid of this annoying effect, we present, an easy to implement, inlining optimization that minimizes code size growth by combining a compile-time algorithm deciding when expansion should occur with different expansion frameworks describing how they should be performed. We present the experimental measures that have driven the design of inline function expansion. We conclude with measurements showing that our optimization succeeds in producing faster codes while avoiding code size increase. Keywords: Compilation, Optimization, Inlining, Functional languages. 1 Introduction Inline function expansion (henceforth "inlining") replaces a function invocation with a modified copy of the function body. Studi...

We describe a type system and typed semantics that use a hierarchy of monads to describe and delimit a variety of effects, including non-termination, exceptions, and state, in a call-by-value functional language. The type system and semantics can be used to organize and justify avariety of optimizing transformations in the presence of effects. In addition, we describe a simple monad inferencing algorithm that computes the minimum effect for each subexpression of a program, and provides more accurate effects information than local syntactic methods.