Hat is a programmer’s tool for generating a trace of a computation of a Haskell 98 program and viewing such a trace in various different ways. Applications include program comprehension and debugging. A new version of Hat uses a stand-alone program transformation to produce self-tracing Haskell programs. The transformation is small and works with any Haskell 98 compiler that implements the stan...

SUMMARY We extend the well-known interval analysis method so that it can be used to gather global flow information for individual array elements. Data dependences between all array accesses in different basic blocks, different iterations of the same loop, and across different loops are computed and represented as labelled arcs in a program flow graph. This approach results in a uniform treatmen...

We introduce symbiotic expressions, a method for algebraic simplification within a compiler, in lieu of an SMT solver, such as Yices or the Omega Calculator. Symbiotic expressions are compiler-generated expressions, temporarily injected into a program's abstract syntax tree (AST). The compiler's normal optimizations interpret and simplify those expressions, making their results available for th...

A compiler source language and internal organization are described, which utilize program block structure to provide a virtual memory capability for linked-list hie.rarchically structured data. A nonprocedural source language notation is introduced, resembling conventional mathematical set notation, for describing the search and selection of the members of subsets of ordered sets. An algorithm ...

The construction of safety-critical real-time applications requires predictable computer platforms that enable a safe and tight static analysis of those systems. The worst-case performance and the availability of tight bounds on the worst-case execution time (WCET) of the tasks of the applications are of central importance in such systems. The compiler tool-chain plays an integral part in a rea...

This paper presents an overview of a parallelizing compiler to automatically generate eecient code for large-scale parallel architec-tures from sequential input programs. This research focuses on loop-level parallelism in dense matrix computations. We illustrate the basic techniques the compiler uses by describing the entire compilation process for a simple example. Our compiler is organized in...

In the eld of real-time systems, accurate estimates of the worst-case execution time of programs are required for real-time modelling and veri cation, scheduling analysis, feasibility analysis, and dimensioning of the system hardware. At present, such estimates are produced by measuring program runs on inputs which are believed to produce long execution times. Unfortunately, such measurements p...

Performing worst case execution time WCET analysis on machine code with program path annota tion provided at high level source code level requires the transformation of path annotations from the source code level to assembly object code level This path information transformation can be done outside or in tegrated into the compiler during code compilation The rst approach is easier to implement ...

This paper proposes solutions to two important problems with parallel programming environments that were not previously addressed. The rst issue is that current compilers are typically black-box tools with which the user has little interaction. Information gathered by the compiler, although potentially very meaningful for the user, is often inaccessible or hard to decipher. Second, compilation ...

Trace based compilation is a technique used in managed language runtimes to detect and compile frequently executed program paths. The goal is reduced compilation time and improved code quality since only “hot” parts of methods are ever compiled. Trace compilation is well suited for interpreter based runtime environments because the control flow of an application program is highly visible and re...