DocumentCode :
754635
Title :
NTUplace3: An Analytical Placer for Large-Scale Mixed-Size Designs With Preplaced Blocks and Density Constraints
Author :
Chen, Tung-Chieh ; Jiang, Zhe-Wei ; Hsu, Tien-Chang ; Chen, Hsin-Chen ; Chang, Yao-Wen
Author_Institution :
Grad. Inst. of Electron. Eng., Nat. Taiwan Univ., Taipei
Volume :
27
Issue :
7
fYear :
2008
fDate :
7/1/2008 12:00:00 AM
Firstpage :
1228
Lastpage :
1240
Abstract :
In addition to wirelength, modern placers need to consider various constraints such as preplaced blocks and density. We propose a high-quality analytical placement algorithm considering wirelength, preplaced blocks, and density based on the log-sum-exp wirelength model proposed by Naylor and the multilevel framework. To handle preplaced blocks, we use a two-stage smoothing technique, i.e., Gaussian smoothing followed by level smoothing, to facilitate block spreading during global placement (GP). The density is controlled by white-space reallocation using partitioning and cut-line shifting during GP and cell sliding during detailed placement. We further use the conjugate gradient method with dynamic step-size control to speed up the GP and macro shifting to find better macro positions. Experimental results show that our placer obtains very high-quality results.
Keywords :
conjugate gradient methods; integrated circuit design; smoothing circuits; NTUplace3; analytical placer; block spreading; cell sliding; conjugate gradient method; cut-line shifting; density constraint; dynamic step-size control; global placement; high-quality analytical placement algorithm; large-scale mixed-size design; log-sum-exp wirelength model; partitioning; two-stage smoothing; white-space reallocation; Algorithm design and analysis; Digital integrated circuits; Gradient methods; Intellectual property; Large-scale systems; Routing; Sliding mode control; Smoothing methods; Transistors; White spaces; Legalization (LG); physical design; placement;
fLanguage :
English
Journal_Title :
Computer-Aided Design of Integrated Circuits and Systems, IEEE Transactions on
Publisher :
ieee
ISSN :
0278-0070
Type :
jour
DOI :
10.1109/TCAD.2008.923063
Filename :
4544855
Link To Document :
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