Variable tracking technique: a single-pass method to determine data dependence

This paper presents a new data dependence checking technique called the variable tracking technique (VTT). It is a single-pass data dependence checking method which locates dependent statements in a serial computer program. VTT produces a schedule which lists the operations in the source code in groups. The list of operations in a particular group can be executed concurrently. The user is not required to provide a profile of the program to the compiler, hence VTT is suitable for applications which automate the process of exploiting parallelism. Here we describe the use of this technique in gacc, a parallelising compiler, which compiles C functions to field programmable gate array (FPGA) circuits. The results presented in this paper show that VTT has been instrumental in gaining improved performance from a parallelising compiler which automates the process of executing the computational intensive portion of the program in hardware