From 3e16f75bc6f490cada2b9c4e9b4962a66b1e8008 Mon Sep 17 00:00:00 2001
From: Keith Rothman <537074+litghost@users.noreply.github.com>
Date: Fri, 1 Mar 2019 14:41:21 -0800
Subject: [PATCH] Revert FF models to include IS_x_INVERTED parameters.

Signed-off-by: Keith Rothman <537074+litghost@users.noreply.github.com>
---
 techlibs/xilinx/cells_sim.v | 40 +++++++++++++++++++++++++++++++------
 1 file changed, 34 insertions(+), 6 deletions(-)

diff --git a/techlibs/xilinx/cells_sim.v b/techlibs/xilinx/cells_sim.v
index 787b37cc8..ff5ff0726 100644
--- a/techlibs/xilinx/cells_sim.v
+++ b/techlibs/xilinx/cells_sim.v
@@ -147,26 +147,54 @@ endmodule
 
 module FDRE (output reg Q, input C, CE, D, R);
   parameter [0:0] INIT = 1'b0;
+  parameter [0:0] IS_C_INVERTED = 1'b0;
+  parameter [0:0] IS_D_INVERTED = 1'b0;
+  parameter [0:0] IS_R_INVERTED = 1'b0;
   initial Q <= INIT;
-  always @(posedge C) if (R) Q <= 1'b0; else if(CE) Q <= D;
+  generate case (|IS_C_INVERTED)
+    1'b0: always @(posedge C) if (R == !IS_R_INVERTED) Q <= 1'b0; else if (CE) Q <= D ^ IS_D_INVERTED;
+    1'b1: always @(negedge C) if (R == !IS_R_INVERTED) Q <= 1'b0; else if (CE) Q <= D ^ IS_D_INVERTED;
+  endcase endgenerate
 endmodule
 
 module FDSE (output reg Q, input C, CE, D, S);
-  parameter [0:0] INIT = 1'b1;
+  parameter [0:0] INIT = 1'b0;
+  parameter [0:0] IS_C_INVERTED = 1'b0;
+  parameter [0:0] IS_D_INVERTED = 1'b0;
+  parameter [0:0] IS_S_INVERTED = 1'b0;
   initial Q <= INIT;
-  always @(posedge C) if (S) Q <= 1'b1; else if(CE) Q <= D;
+  generate case (|IS_C_INVERTED)
+    1'b0: always @(posedge C) if (S == !IS_S_INVERTED) Q <= 1'b1; else if (CE) Q <= D ^ IS_D_INVERTED;
+    1'b1: always @(negedge C) if (S == !IS_S_INVERTED) Q <= 1'b1; else if (CE) Q <= D ^ IS_D_INVERTED;
+  endcase endgenerate
 endmodule
 
 module FDCE (output reg Q, input C, CE, D, CLR);
   parameter [0:0] INIT = 1'b0;
+  parameter [0:0] IS_C_INVERTED = 1'b0;
+  parameter [0:0] IS_D_INVERTED = 1'b0;
+  parameter [0:0] IS_CLR_INVERTED = 1'b0;
   initial Q <= INIT;
-  always @(posedge C, posedge CLR) if (CLR) Q <= 1'b0; else if (CE) Q <= D;
+  generate case ({|IS_C_INVERTED, |IS_CLR_INVERTED})
+    2'b00: always @(posedge C, posedge CLR) if ( CLR) Q <= 1'b0; else if (CE) Q <= D ^ IS_D_INVERTED;
+    2'b01: always @(posedge C, negedge CLR) if (!CLR) Q <= 1'b0; else if (CE) Q <= D ^ IS_D_INVERTED;
+    2'b10: always @(negedge C, posedge CLR) if ( CLR) Q <= 1'b0; else if (CE) Q <= D ^ IS_D_INVERTED;
+    2'b11: always @(negedge C, negedge CLR) if (!CLR) Q <= 1'b0; else if (CE) Q <= D ^ IS_D_INVERTED;
+  endcase endgenerate
 endmodule
 
 module FDPE (output reg Q, input C, CE, D, PRE);
-  parameter [0:0] INIT = 1'b1;
+  parameter [0:0] INIT = 1'b0;
+  parameter [0:0] IS_C_INVERTED = 1'b0;
+  parameter [0:0] IS_D_INVERTED = 1'b0;
+  parameter [0:0] IS_PRE_INVERTED = 1'b0;
   initial Q <= INIT;
-  always @(negedge C, posedge PRE) if (PRE) Q <= 1'b1; else if (CE) Q <= D;
+  generate case ({|IS_C_INVERTED, |IS_PRE_INVERTED})
+    2'b00: always @(posedge C, posedge PRE) if ( PRE) Q <= 1'b1; else if (CE) Q <= D ^ IS_D_INVERTED;
+    2'b01: always @(posedge C, negedge PRE) if (!PRE) Q <= 1'b1; else if (CE) Q <= D ^ IS_D_INVERTED;
+    2'b10: always @(negedge C, posedge PRE) if ( PRE) Q <= 1'b1; else if (CE) Q <= D ^ IS_D_INVERTED;
+    2'b11: always @(negedge C, negedge PRE) if (!PRE) Q <= 1'b1; else if (CE) Q <= D ^ IS_D_INVERTED;
+  endcase endgenerate
 endmodule
 
 module FDRE_1 (output reg Q, input C, CE, D, R);
-- 
2.30.2