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| author | Eddie Hung <eddie@fpgeh.com> | 2019-07-08 11:08:20 -0700 |
|---|---|---|
| committer | Eddie Hung <eddie@fpgeh.com> | 2019-07-08 11:08:20 -0700 |
| commit | dbe1326573e878f4f9d4fc80ce1afcd0f7d84ec6 (patch) | |
| tree | 816abf008f57e20979720f6b292c5835ad5fb824 /techlibs | |
| parent | eb19abbb448900645e733f39831ff5b0a6f2e0db (diff) | |
| download | yosys-dbe1326573e878f4f9d4fc80ce1afcd0f7d84ec6.tar.gz yosys-dbe1326573e878f4f9d4fc80ce1afcd0f7d84ec6.tar.bz2 yosys-dbe1326573e878f4f9d4fc80ce1afcd0f7d84ec6.zip | |
Parametric muxcover costs as per @daveshah1
Diffstat (limited to 'techlibs')
| -rw-r--r-- | techlibs/xilinx/synth_xilinx.cc | 30 |
1 files 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); } |