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When RTL designers define the hierarchy of a system, they exploit their knowledge about the conceptual abstractions devised during the design and the functional interactions between the logical components. This valuable information is often lost during physical synthesis. This paper proposes HiDaP, a novel multi-level algorithm that uses RTL information and analytical methods for the macro placement problem of modern designs dominated by multi-cycle connection pipelines. By taking advantage of the hierarchy tree, the netlist is divided into blocks containing macros and standard cells, and their dataflow affinity is inferred considering the register latency and flow width of their interaction. The layout is represented using slicing structures and generated with a top-down algorithm capable of handling blocks with both hard and soft components. An adaptive multi-objective cost function is used to simultaneously minimize wirelength, timing, overlap and distance to preferred locations, which can be user-defined or generated by analytic methods (spectral and force-directed). These techniques have been applied to a set of large industrial circuits and compared against state-of-theart commercial and academic placers, and also to handcrafted floorplans generated by expert back-end engineers. The proposed approach outperforms previous algorithmic methods and can produce solutions with better wirelength and timing than the best handcrafted floorplans. Post-routing layouts are almost brought to timing closure and DRC cleanness with minimal engineer modification, showing that the generated floorplans provide an excellent starting point for the physical design flow and contribute to reduce turn-around time significantly. This work has been partially supported by a grant from Inphi Corporation and funds from the Spanish Ministry for Economy and Competitiveness and the European Union (FEDER funds) under grant TIN2017-86727-C2-1-R, and the Generalitat de Catalunya (2017 SGR 786).

Elasticity is a paradigm that tolerates the variations in computation and communication delays. By applying elastic transformations that allow varying the original timing, circuits can be optimized beyond the conventional rigid transformations that do not modify the external timing. Pipelining is one of the classical techniques to improve the throughput of a circuit. This article reveals how elasticity can be effectively and practically used to derive pipelined circuits by using correct-by-construction transformations that can be fully automated. Two designs, one of them industrial, are used to demonstrate how the area-performance trade-off can be explored using elasticity.

Design automation has been one of the main propellers of the semiconductor industry with logic synthesis being one of the core technologies in this field. This article reviews the evolution of logic synthesis until the advent of techniques for automatic pipelining based on elastic timing, either synchronous or asynchronous. The emergence of these techniques can enable a productive interaction with tools that can do microarchitectural exploration of complex designs.