[11] | 1 | # Generic script file for creating the next state relation of a system. |
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| 2 | |
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| 3 | # Author: Rajeev K. Ranjan |
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| 4 | |
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| 5 | # Usage: |
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| 6 | # After reading in the design using one of |
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| 7 | # "read_blif, read_blif_mv, or read_verilog" commands, |
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| 8 | # on VIS prompt type: |
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| 9 | # source script_generic.simple |
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| 10 | # |
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| 11 | # Trouble shooting: |
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| 12 | # i) Invoke the script exactly the way prescribed (no option to "source") |
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| 13 | # ii) The script tries to create a file in the current directory. Make sure |
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| 14 | # that the directory is writable by you. |
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| 15 | |
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| 16 | ### Script starts here ################################################# |
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| 17 | |
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| 18 | # Get rid of the aliases for the commands used in this file |
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| 19 | |
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| 20 | unalias flatten_hierarchy |
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| 21 | unalias static_order |
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| 22 | unalias build_partition_mdds |
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| 23 | unalias print_img_info |
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| 24 | unalias compute_reach |
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| 25 | unalias dynamic_var_ordering |
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| 26 | unalias write_order |
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| 27 | |
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| 28 | # flatten the hierarchy |
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| 29 | flatten_hierarchy |
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| 30 | |
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| 31 | # Variable ordering, assuming the default has taken care of the best |
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| 32 | # setting. |
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| 33 | |
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| 34 | static_order |
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| 35 | |
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| 36 | # Build the next state functions. Use the frontier method such that in |
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| 37 | # case of very large examples, we can create intermediate variables |
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| 38 | # and have a handle on the BDD size. |
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| 39 | |
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| 40 | # We do not want next state functions to have more than 5000 nodes. |
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| 41 | |
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| 42 | set partition_threshold 5000 |
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| 43 | build_partition_mdds frontier |
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| 44 | |
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| 45 | # Next create the next state relation, create clusters and |
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| 46 | # order them. |
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| 47 | |
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| 48 | # Use the method published in IWLS 95. |
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| 49 | # And set the appropriate parameters |
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| 50 | |
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| 51 | set image_method iwls95 |
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| 52 | |
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| 53 | # Make clusters of no larger than 5000 |
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| 54 | |
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| 55 | set image_cluster_size 5000 |
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| 56 | |
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| 57 | # This command is a clumsy way to create the next state relations. |
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| 58 | |
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| 59 | print_img_info |
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| 60 | |
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| 61 | # Invoke the sifting operation to reduce the BDD size |
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| 62 | |
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| 63 | dynamic_var_ordering -f sift |
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| 64 | |
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| 65 | # Save the ordering in a file, to be used later (using a unique name). |
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| 66 | |
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| 67 | write_order __vis.order |
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| 68 | |
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| 69 | # Restart the computation |
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| 70 | |
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| 71 | flatten_hierarchy |
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| 72 | |
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| 73 | # Use the variable ordering obtained after reordering. |
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| 74 | |
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| 75 | static_order -s input_and_latch __vis.order |
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| 76 | |
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| 77 | build_partition_mdds frontier |
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| 78 | |
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| 79 | # This command is a clumsy way to create the next state relations. |
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| 80 | |
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| 81 | print_img_info |
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