Many modern embedded applications, such as mobile
communication or multi-media, pose high requirements on the computing
performance of the underlying system architecture as well as on the
power consumption. Contemporary processor architectures based on Very
Long Instruction Word (VLIW) can satisfy these requirements by
intensely exploiting
instruction-level parallelism and thus simultaneously increasing
computation speed and reducing power consumption. Unfortunately, many
applications possess an unsatisfactory performance, nonetheless. This
is because the code generation of traditional compilers is not suited
to exploit the specific characteristics and irregularities of VLIW
architectures efficiently.
To improve the code performance an indirect code generation is proposed in this
thesis for VLIW architectures to translate the efficient compiled assembly code
for RISC architectures into the target VLIW assembly. The indirect approach
consists of three steps: 1) efficient compilation of the source code for an
arbitrary RISC architecture supported by a traditional optimizing compiler; 2)
a "pre-processing" step to further optimize the RISC assembly and translate it
into a RISC-like assembly that is already closely related to the target VLIW
architecture using a static binary translator; 3) a ”post-processing” step as
target specific compiler back-end with VLIW specific optimizations. This
indirect code generation approach enables the exploitation of the architectural
benefits of VLIW processors while the highly efficient optimizations of
traditional RISC compiler techniques can be obtained simultaneously without
compromising each other.
Furthermore, the importance of joint software and hardware design is well-known
to achieve high system efficiency. Therefore, an additional algorithm is
proposed within the scope of this thesis that is intended to support the
hardware exploration of the target VLIW architecture. A fuzzy control system
(based on fuzzy set theory) is used to find an optimal application-specific
processor configuration with respect to the necessary degree of parallelism.
Different code- as well as hardware-specific performance parameters are
considered by the optimization algorithm in the step. To prove the quality of
the proposed indirect code generation and hardware exploration, a low-power
scalar VLIW processor is implemented in this thesis based on Synchronous
Transfer Architecture (STA). This architecture exhibits special irregular
characteristics, and is thus well suited as candidate for this
prove-of-concept.
Xiaoyan Jia
Assembler Benchmark Codegenerierung Energieeinsparung Fuzzy-Regelsystem Hardwareentwurf Leistungssteigerung Optimierender Compiler RISC VLIW-Architektur