The Trimaran Project
In 1998, Hewlett-Packard established the Trimaran project, which was completed as part of a consortium of three different universities' computing departments. HP released directly to the universities compiler information, especially as it related to HP-UX, around the EPIC concepts and asked them to develop a new compiler based on its precepts. The release of this research compiler that is billed as an academic “infrastructure” was aimed at enabling universities to develop compiler technology for EPIC.
Compilers have always been a crucial part in making PA-RISC work as well as it has. However, the move into the EPIC architecture and meeting the challenges of object-oriented code quickly made HP realize that compilers were immensely more important. Because of this, HP predicted that the time spent releasing the compiler for testing would pay off 5 years in the future—it was very much correct in that prediction.
In addition to HP's own lab work, the Itanium architecture has benefited from 4 years of development and testing done on these campuses. By any standards, the testing has been rigorous and thorough. In fact, an estimated 100 million lines of code have been run through the compilers in development across HP-UX, Windows, and Linux—creating a compiler with unmatched maturity in the development cycle that is ready for prime time in the new EPIC architecture.
One of the major benefits of working directly with Intel is that Hewlett-Packard gained more experience working with compilers. Instead of working with a single operating system and creating applications for it, HP was able to release over 100 different applications in three different operating systems.
The current HP-UX compilers are extremely mature for this point in the development cycle of a new architecture. They also come with many of the qualities that make them ideal for work in the EPIC world:
Ability to vary parameters such as the instruction width.
An emulator that can execute code for detailed simulations performance.
A source-level environment.
A code generator.
Full support for predication and speculation.
A suite of optimization modules, enabling tasks such as loop unrolling and global scheduling.
It's predicted that the up and coming Itanium processors will alter and reshape cooperation between the hardware and the compiler. EPIC architecture itself will contain a large number of execution units. The compiler will organize instructions into specific data streams that can be simultaneously executed. Because of this, compilers that comprise the specific qualities that the Trimaran project put forward will be very much in the driver's seat when it comes to the Itanium processors' ultimate performance.