By default this command distributes and places all the spare cells evenly

By default this command distributes and places all

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By default, this command distributes and places all the spare cells evenly throughout the core area. You can specify the spare cells to place by using one of the following two methods: To place specific spare cells, use the -cells option. To place all the spare cells that belong to specific voltage areas, use the -voltage_areas option. You can specify an area within which to place the spare cells by using the -boundary option. 2. Legalize the spare cells by using the place_eco_cells –legalize_only –cells command. The following example places all spare cells within a specified boundary and legalizes them: icc2_shell> spread_spare_cells -boundary {{100 150} {650 500}} icc2_shell> place_eco_cells -legalize_only \ -cells [get_cells -hierarchical spares*]
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Chapter 11: ECO Flow Automatically Adding Spare Cells 11-10 IC Compiler™ II Implementation User Guide L-2016.03-SP4 IC Compiler™ II Implementation User Guide Version L-2016.03-SP4 Automatically Adding Spare Cells You can add and place spare cells to a legalized design by using the add_spare_cells command after you perform placement and optimization. When you use this command, you must specify the following information: A name prefix for the spare cells by using the -cell_name option The type and number of spare cells to insert by using one of the following two methods: Specify the library cells to use for the spare cell and the number of instances of each library cell by using the -lib_cell and -num_instances options For example, to insert 250 instances each of the AND2 and OR2 library cells, use the following command: icc2_shell> add_spare_cells -cell_name spare1 \ -lib_cell {AND2 OR2} -num_instances 250 Specify the library cells and a different number of instances for each library cell by using the -num_cells option For example, to insert 200 instances of the NAND2 library cell and 150 instances of the NOR2 library cell, use the following command: icc2_shell> add_spare_cells -cell_name spare2 \ -num_cells {NAND2 200 NOR 150} By default, the command distributes the spare cells evenly throughout the design. However, you can control the distribution of the spare cells by using one of the following three methods: To distribute the spare cells within a specific hierarchical block, use the -hier_cell option. When you use this option, the tool distributes the spare cells in a rectangular area that encloses all of the cells that belong to the specified hierarchical block. To distribute the spare cells within a specific bounding box, use the -boundary option. To distribute the spare cells within specific voltage areas, use the -voltage_areas option. The add_spare_cells command places spare cells, but does not legalize them. To legalize these cells, use the place_eco_cells -legalize_only -cells command.
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Chapter 11: ECO Flow Adding Programmable Spare Cells 11-11 IC Compiler™ II Implementation User Guide Version L-2016.03-SP4 The following example adds spare cells using the add_spare_cells command and legalizes them: icc2_shell> add_spare_cells -lib_cell {INV} -num_instances 400 \ -cell_name spares
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