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Add some spacing

This commit is contained in:
Eddie Hung 2019-07-10 12:32:33 -07:00
parent 521971e32e
commit 58bb84e5b2
1 changed files with 9 additions and 9 deletions
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18
techlibs/xilinx/cells_map.v
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@ -220,15 +220,15 @@ module \$__XILINX_SHIFTX (A, B, Y);
// This has the effect of more effectively utilising the hard mux;
// take for example a 5:1 multiplexer, currently this would map as:
//
// A[0] \___ __ A[0] \__ __
// A[4] / \| \ whereas the more A[1] / \| \
// A[1] _____| | obvious mapping A[2] \___| |
// A[2] _____| |-- of MSBs to hard A[3] / | |__
// A[3]______| | resources would A[4] ____| |
// |__/ lead to: 1'bx ____| |
// || |__/
// || ||
// B[1:0] B[1:2]
// A[0] \___ __ A[0] \__ __
// A[4] / \| \ whereas the more A[1] / \| \
// A[1] _____| | obvious mapping A[2] \___| |
// A[2] _____| |-- of MSBs to hard A[3] / | |__
// A[3]______| | resources would A[4] ____| |
// |__/ lead to: 1'bx ____| |
// || |__/
// || ||
// B[1:0] B[1:2]
//
// Expectation would be that the 'forward' mapping (right) is more
// area efficient (consider a 9:1 multiplexer using 2x4:1 multiplexers