From dbe1326573e878f4f9d4fc80ce1afcd0f7d84ec6 Mon Sep 17 00:00:00 2001 From: Eddie Hung Date: Mon, 8 Jul 2019 11:08:20 -0700 Subject: [PATCH] Parametric muxcover costs as per @daveshah1 --- techlibs/xilinx/synth_xilinx.cc | 30 ++++++++++++++---------------- 1 file changed, 14 insertions(+), 16 deletions(-) diff --git a/techlibs/xilinx/synth_xilinx.cc b/techlibs/xilinx/synth_xilinx.cc index c18c3918f..f43923afb 100644 --- a/techlibs/xilinx/synth_xilinx.cc +++ b/techlibs/xilinx/synth_xilinx.cc @@ -280,23 +280,21 @@ struct SynthXilinxPass : public ScriptPass } else if (widemux > 0) { run("simplemap t:$mux"); - std::string muxcover_args = " -nodecode"; + constexpr int cost_mux2 = 100; + std::string muxcover_args = stringf(" -nodecode -mux2=%d", cost_mux2); switch (widemux) { - // NB: Cost of mux2 is 100; mux8 should cost between 3 and 4 - // of those so that 4:1 muxes and below are implemented - // out of mux2s - case 5: muxcover_args += " -mux8=350 -mux16=400"; break; - case 6: muxcover_args += " -mux8=450 -mux16=500"; break; - case 7: muxcover_args += " -mux8=550 -mux16=600"; break; - case 8: muxcover_args += " -mux8=650 -mux16=700"; break; - case 9: muxcover_args += " -mux16=750"; break; - case 10: muxcover_args += " -mux16=850"; break; - case 11: muxcover_args += " -mux16=950"; break; - case 12: muxcover_args += " -mux16=1050"; break; - case 13: muxcover_args += " -mux16=1150"; break; - case 14: muxcover_args += " -mux16=1250"; break; - case 15: muxcover_args += " -mux16=1350"; break; - default: muxcover_args += " -mux16=1450"; break; + case 5: + case 6: + case 7: + case 8: muxcover_args += stringf(" -mux8=%d -mux16=%d", cost_mux2*(widemux-1)-1, cost_mux2*(widemux-1)); break; + case 9: + case 10: + case 11: + case 12: + case 13: + case 14: + case 15: + default: muxcover_args += stringf(" -mux16=%d", cost_mux2*(widemux-1)-1); break; } run("muxcover " + muxcover_args); } -- 2.30.2