From 846f12aa2e0070727ace559817139bfffe50abce Mon Sep 17 00:00:00 2001
From: Madeleine Masser-Frye <51804758+mmasserfrye@users.noreply.github.com>
Date: Wed, 6 Jul 2022 00:08:59 +0000
Subject: [PATCH] new priority onehot module for better area/time

---
 pipelined/src/generic/priorityonehot.sv | 10 ++++++----
 synthDC/Makefile                        |  6 +++---
 synthDC/scripts/synth.tcl               |  3 ++-
 3 files changed, 11 insertions(+), 8 deletions(-)

diff --git a/pipelined/src/generic/priorityonehot.sv b/pipelined/src/generic/priorityonehot.sv
index bf9d041b..e2c79cd6 100644
--- a/pipelined/src/generic/priorityonehot.sv
+++ b/pipelined/src/generic/priorityonehot.sv
@@ -39,9 +39,11 @@ module priorityonehot #(parameter N = 8) (
   input  logic  [N-1:0] a,
   output logic  [N-1:0] y
 );
-  logic [N-1:0] nolower;
 
-  // create thermometer code mask
-  prioritythermometer #(N) maskgen(.a({a[N-2:0], 1'b0}), .y(nolower));
-  assign y = a & nolower;
+  genvar i;
+  assign y[0] = a[0];
+  for (i=1; i<N; i++) begin:poh
+    assign y[i] = a[i] & ~|a[i-1:0];
+  end
+
 endmodule
diff --git a/synthDC/Makefile b/synthDC/Makefile
index 611dcfef..115302ec 100755
--- a/synthDC/Makefile
+++ b/synthDC/Makefile
@@ -5,8 +5,8 @@ NAME := synth
 
 # defaults
 export DESIGN ?= wallypipelinedcore
-export FREQ ?= 3402
-export CONFIG ?= rv32e
+export FREQ ?= 3000
+export CONFIG ?= rv32gc
 # sky130 and sky90 presently supported
 export TECH ?= tsmc28
 # MAXCORES allows parallel compilation, which is faster but less CPU-efficient
@@ -14,7 +14,7 @@ export TECH ?= tsmc28
 export MAXCORES ?= 4
 # MAXOPT turns on flattening, boundary optimization, and retiming
 # The output netlist is hard to interpret, but significantly better PPA
-export MAXOPT ?= 0
+export MAXOPT ?= 1
 export DRIVE ?= FLOP
 
 time := $(shell date +%F-%H-%M)
diff --git a/synthDC/scripts/synth.tcl b/synthDC/scripts/synth.tcl
index 4d444682..dc6001f3 100755
--- a/synthDC/scripts/synth.tcl
+++ b/synthDC/scripts/synth.tcl
@@ -102,7 +102,8 @@ set_critical_range [expr $my_period*0.05] $current_design
 
 # Partitioning - flatten or hierarchically synthesize
 if { $maxopt == 1 } {
-    ungroup -all -flatten -simple_names
+    ungroup -all -simple_names
+    # -flatten 
 }
 
 # Set input pins except clock