From 0ca397f087287307d13daac57f60c24c6f2a982e Mon Sep 17 00:00:00 2001 From: Eddie Hung Date: Tue, 20 Aug 2019 15:10:01 -0700 Subject: [PATCH] Deprecate `abc_scc_break` attribute --- README.md | 8 -------- 1 file changed, 8 deletions(-) diff --git a/README.md b/README.md index 56f428548..fe30348eb 100644 --- a/README.md +++ b/README.md @@ -409,14 +409,6 @@ Verilog Attributes and non-standard features blackbox or whitebox definition to a corresponding entry in a `abc9` box-file. -- The port attribute ``abc_scc_break`` indicates a module input port that will - be treated as a primary output during `abc9` techmapping. Doing so eliminates - the possibility of a strongly-connected component (i.e. a combinatorial loop) - existing. Typically, this is specified for sequential inputs on otherwise - combinatorial boxes -- for example, applying ``abc_scc_break`` onto the `D` - port of a LUTRAM cell prevents `abc9` from interpreting any `Q` -> `D` paths - as a combinatorial loop. - - The port attribute ``abc_carry`` marks the carry-in (if an input port) and carry-out (if output port) ports of a box. This information is necessary for `abc9` to preserve the integrity of carry-chains. Specifying this attribute -- 2.30.2