Merge pull request #2077 from YosysHQ/eddie/abc9_dff_improve

abc9: -dff improvements

1 files changed, 53 insertions, 4 deletions

diff --git a/tests/arch/xilinx/abc9_dff.ys b/tests/arch/xilinx/abc9_dff.ys
index fd343969b..210e87477 100644
--- a/tests/arch/xilinx/abc9_dff.ys
+++ b/tests/arch/xilinx/abc9_dff.ys
@@ -50,10 +50,10 @@ FDCE_1 /*#(.INIT(1))*/ fd7(.C(C), .CE(1'b0), .D(D), .CLR(1'b0), .Q(Q[6]));
 FDPE_1 #(.INIT(1)) fd8(.C(C), .CE(1'b0), .D(D), .PRE(1'b0), .Q(Q[7]));
 endmodule
 EOT
-logger -expect warning "Module '\$paramod\\FDRE\\INIT=1' contains a \$dff cell .*" 1
-logger -expect warning "Module '\$paramod\\FDRE_1\\INIT=1' contains a \$dff cell .*" 1
-logger -expect warning "Module 'FDSE' contains a \$dff cell .*" 1
-logger -expect warning "Module '\$paramod\\FDSE_1\\INIT=1' contains a \$dff cell .*" 1
+logger -expect warning "Whitebox '\$paramod\\FDRE\\INIT=1' with \(\* abc9_flop \*\) contains a \$dff cell with non-zero initial state -- this is not supported for ABC9 sequential synthesis. Treating as a blackbox\." 1
+logger -expect warning "Whitebox '\$paramod\\FDRE_1\\INIT=1' with \(\* abc9_flop \*\) contains a \$dff cell with non-zero initial state -- this is not supported for ABC9 sequential synthesis. Treating as a blackbox\." 1
+logger -expect warning "Whitebox 'FDSE' with \(\* abc9_flop \*\) contains a \$dff cell with non-zero initial state -- this is not supported for ABC9 sequential synthesis. Treating as a blackbox\." 1
+logger -expect warning "Whitebox '\$paramod\\FDSE_1\\INIT=1' with \(\* abc9_flop \*\) contains a \$dff cell with non-zero initial state -- this is not supported for ABC9 sequential synthesis. Treating as a blackbox\." 1
 equiv_opt -assert -multiclock -map +/xilinx/cells_sim.v synth_xilinx -abc9 -dff -noiopad -noclkbuf
 design -load postopt
 select -assert-count 8 t:FD*
@@ -82,4 +82,53 @@ select -assert-count 1 t:FDPE
 select -assert-count 2 t:INV
 select -assert-count 0 t:FD* t:INV %% t:* %D
 
+
+design -reset
+read_verilog <<EOT
+module top(input clk, input d, output q);
+reg r;
+always @(posedge clk) begin
+r <= d;
+end
+assign q = ~r;
+endmodule
+EOT
+proc
+equiv_opt -assert -multiclock -map +/xilinx/cells_sim.v synth_xilinx -abc9 -dff -noiopad -noclkbuf
+design -load postopt
+select -assert-count 1 t:FDRE %co w:r %i
+
+
+design -reset
+read_verilog <<EOT
+module top(input clk, input a, b, output reg q1, output q2);
+reg r;
+always @(posedge clk) begin
+    q1 <= a | b;
+    r <= ~(~a & ~b);
+end
+assign q2 = r;
+endmodule
+EOT
+proc
+equiv_opt -assert -multiclock -map +/xilinx/cells_sim.v synth_xilinx -abc9 -dff -noiopad -noclkbuf
+design -load postopt
+select -assert-count 1 t:FDRE %co %a w:r %i
+
+
+design -reset
+read_verilog <<EOT
+module top(input clk, input a, b, output o);
+reg r1, r2;
+always @(posedge clk) begin
+    r1 <= a | b;
+    r2 <= ~(~a & ~b);
+end
+assign o = r1 | r2;
+endmodule
+EOT
+proc
+equiv_opt -assert -multiclock -map +/xilinx/cells_sim.v synth_xilinx -abc9 -dff -noiopad -noclkbuf
+
+
 logger -expect-no-warnings