This thesis addresses two ubiquitous trends in the embedded system world - the increasing importance of design turnaround time as a design metric, and the move towards closing the design productivity gap. Adopting the right choice of design approach has been recognised as an integral part of the design flow in order to meet desired characteristics such as increasing software content, satisfying the growing complexities of an application, reusing off-the-shelf components, and exploring design metrics tradeoff, which closes the design productivity gap. The importance of design turnaround time is motivated by the intensive competition between manufacturers, especially makers of mainstream electronic consumer products, who shrinks the product life cycle and requires faster time-to-market to maximise economic benefits. This thesis presents a suite of design automation methodologies to automatically design embedded systems for an application in the state-of-the-art design approach - the extensible processor platform. These design automation methodologies systematise the extensible processor platform???s design flow, with particular emphasis on solving four challenging design problems: i) code segment identification; ii) instruction generation; iii) architectural customisation selection; and iv) processor evaluation. Our suite of design automation methodologies includes: i) a semi-automatic design system - to design an extensible processor that maximises the application performance while satisfying the area constraint. By specifying a fitting function to identify suitable code segments within an application, a two-level hierarchy selection algorithm is used to first select a predefined processor and then select the right instruction, and a performance estimator is used to estimate an application's performance; ii) a tool to match instructions - to automatically match the pre-designed instructions with computationally intensive code segments, reducing verification time and effort; iii) an instructions estimation model - to estimate the area overhead, latency, power consumption of extensible instructions, exploring larger design space; and iv) an instructions generation tool - to generate new extensible instructions that maximises the speedup while minimising power dissipation. A number of techniques such as system decomposition, combinational equivalence checking and regression analysis etc., have been heavily relied upon in the creation of the final design system. This thesis shows results at every stage to demonstrate the efficacy of our design methodologies in the creation of extensible processors. The methodologies and results presented in this thesis demonstrate that automating the design process for an extensible processor platform results in significant performance increase - on average, an increase of 4.74x (up to 15.71x) compared to the original base processor. Our system achieves significant design turnaround time savings (2.5% of the full simulation time for the entire design space) with majority Pareto points obtained (91% on average), and can lead to fewer and faster design iterations. Our instruction matching tool is 7.3x faster on average compared to the best known approaches to the problem (partial simulations). Our estimation model has a mean absolute error as small as 3.4% (6.7% max.) for area overhead, 5.9% (9.4% max.) for latency, and 4.2% (7.2% max.) for power consumption, compared to estimation through the time consuming synthesis and simulation steps using commercial tools. Finally, the instruction generation tool reduces energy consumption by a further 5.8% on average (up to 17.7%) compared to extensible instructions generated by previous approaches.

This thesis addresses two ubiquitous trends in the embedded system world - the increasing importance of design turnaround time as a design metric, and the move towards closing the design productivity gap. Adopting the right choice of design approach has been recognised as an integral part of the design flow in order to meet desired characteristics such as increasing software content, satisfying the growing complexities of an application, reusing off-the-shelf components, and exploring design metrics tradeoff, which closes the design productivity gap. The importance of design turnaround time is motivated by the intensive competition between manufacturers, especially makers of mainstream electronic consumer products, who shrinks the product life cycle and requires faster time-to-market to maximise economic benefits. This thesis presents a suite of design automation methodologies to automatically design embedded systems for an application in the state-of-the-art design approach - the extensible processor platform. These design automation methodologies systematise the extensible processor platform???s design flow, with particular emphasis on solving four challenging design problems: i) code segment identification; ii) instruction generation; iii) architectural customisation selection; and iv) processor evaluation. Our suite of design automation methodologies includes: i) a semi-automatic design system - to design an extensible processor that maximises the application performance while satisfying the area constraint. By specifying a fitting function to identify suitable code segments within an application, a two-level hierarchy selection algorithm is used to first select a predefined processor and then select the right instruction, and a performance estimator is used to estimate an application's performance; ii) a tool to match instructions - to automatically match the pre-designed instructions with computationally intensive code segments, reducing verification time and effort; iii) an instructions estimation model - to estimate the area overhead, latency, power consumption of extensible instructions, exploring larger design space; and iv) an instructions generation tool - to generate new extensible instructions that maximises the speedup while minimising power dissipation. A number of techniques such as system decomposition, combinational equivalence checking and regression analysis etc., have been heavily relied upon in the creation of the final design system. This thesis shows results at every stage to demonstrate the efficacy of our design methodologies in the creation of extensible processors. The methodologies and results presented in this thesis demonstrate that automating the design process for an extensible processor platform results in significant performance increase - on average, an increase of 4.74x (up to 15.71x) compared to the original base processor. Our system achieves significant design turnaround time savings (2.5% of the full simulation time for the entire design space) with majority Pareto points obtained (91% on average), and can lead to fewer and faster design iterations. Our instruction matching tool is 7.3x faster on average compared to the best known approaches to the problem (partial simulations). Our estimation model has a mean absolute error as small as 3.4% (6.7% max.) for area overhead, 5.9% (9.4% max.) for latency, and 4.2% (7.2% max.) for power consumption, compared to estimation through the time consuming synthesis and simulation steps using commercial tools. Finally, the instruction generation tool reduces energy consumption by a further 5.8% on average (up to 17.7%) compared to extensible instructions generated by previous approaches.