mirrors/yosys
3
0
Fork 0
mirror of https://github.com/YosysHQ/yosys synced 2025-07-31 00:13:18 +00:00
Code Activity

proc_rmdead: use explicit pattern set when there are no wildcards

Browse source 
If width of a case expression was large, explicit patterns could cause
the existing logic to take an extremely long time, or exhaust the
maximum size of the underlying set. For cases where all of the patterns
are fully defined and there are no constants in the case expression,
this change uses a simple set to track which patterns have been seen.
This commit is contained in:
Zachary Snow 2021-07-28 17:34:24 -04:00 • committed by Zachary Snow
parent 4fec3a85cd
commit c016f6a423
4 changed files with 386 additions and 2 deletions
Download patch file Download diff file Expand all files Collapse all files

46
tests/proc/rmdead.v Normal file
View file

@ -0,0 +1,46 @@
module top (
input wire signed x,
output reg [31:0] y
);
wire signed fail = ~x;
always @*
case (x)
1'b0: y = 0;
1'b1: y = 1;
default: y = fail;
endcase
always @*
case (x)
2'sb00: y = 0;
2'sb00: y = fail;
endcase
always @*
case (x)
2'sb00: y = 0;
default: y = fail;
2'sb01: y = 1;
2'sb10: y = 2;
2'sb11: y = 3;
2'sb00: y = fail;
2'sb01: y = fail;
2'sb10: y = fail;
2'sb11: y = fail;
endcase
always @*
case ({x, x})
2'b00: y = 0;
2'b01: y = 1;
2'b10: y = 2;
2'b11: y = 3;
default: y = fail;
2'b00: y = fail;
2'b01: y = fail;
2'b10: y = fail;
2'b11: y = fail;
endcase
endmodule

4
tests/proc/rmdead.ys Normal file
View file

@ -0,0 +1,4 @@
read_verilog rmdead.v
proc
opt_clean
select -assert-count 0 w:fail

273
tests/simple/case_large.v Normal file
View file

@ -0,0 +1,273 @@
module top (
input wire [127:0] x,
output reg [31:0] y
);
localparam A = 32'hDEAD_BEEF;
localparam B = 32'h0BAD_0B01;
localparam C = 32'hC001_D00D;
localparam D = 32'h1234_5678;
always @*
case (x)
{C,A,D,B}: y = 142;
{C,A,D,A}: y = 141;
{D,D,A,A}: y = 241;
{A,C,C,D}: y = 44;
{A,A,A,C}: y = 3;
{A,B,A,C}: y = 19;
{A,D,C,C}: y = 59;
{A,A,C,C}: y = 11;
{D,C,B,B}: y = 230;
{A,A,D,D}: y = 16;
{A,C,A,A}: y = 33;
{A,D,D,D}: y = 64;
{D,B,C,B}: y = 218;
{A,C,B,D}: y = 40;
{C,A,B,B}: y = 134;
{A,C,C,C}: y = 43;
{D,A,D,D}: y = 208;
{A,B,C,A}: y = 25;
{B,A,B,B}: y = 70;
{A,C,B,B}: y = 38;
{C,C,C,B}: y = 170;
{C,D,A,C}: y = 179;
{B,C,D,B}: y = 110;
{A,D,A,C}: y = 51;
{C,C,B,B}: y = 166;
{D,D,D,B}: y = 254;
{C,A,D,C}: y = 143;
{C,D,D,B}: y = 190;
{C,B,A,A}: y = 145;
{C,B,A,C}: y = 147;
{B,C,C,B}: y = 106;
{C,D,C,A}: y = 185;
{C,D,B,D}: y = 184;
{D,D,D,D}: y = 256;
{D,C,C,C}: y = 235;
{D,C,D,B}: y = 238;
{A,B,D,C}: y = 31;
{A,C,A,D}: y = 36;
{C,B,C,B}: y = 154;
{A,B,A,A}: y = 17;
{C,B,B,A}: y = 149;
{B,B,D,C}: y = 95;
{B,D,C,B}: y = 122;
{D,B,A,A}: y = 209;
{B,A,B,A}: y = 69;
{B,A,D,A}: y = 77;
{A,B,B,B}: y = 22;
{C,C,C,C}: y = 171;
{C,A,C,B}: y = 138;
{B,A,D,D}: y = 80;
{C,D,D,C}: y = 191;
{B,A,A,C}: y = 67;
{D,C,D,C}: y = 239;
{C,D,D,D}: y = 192;
{C,D,B,B}: y = 182;
{B,B,A,C}: y = 83;
{D,A,A,D}: y = 196;
{A,C,C,B}: y = 42;
{B,C,A,A}: y = 97;
{A,D,B,A}: y = 53;
{D,D,B,C}: y = 247;
{A,A,C,A}: y = 9;
{D,A,C,B}: y = 202;
{A,C,B,C}: y = 39;
{B,C,B,A}: y = 101;
{B,B,B,C}: y = 87;
{C,B,A,B}: y = 146;
{B,D,A,D}: y = 116;
{A,B,D,D}: y = 32;
{B,A,B,C}: y = 71;
{C,A,A,A}: y = 129;
{B,A,D,C}: y = 79;
{B,A,C,B}: y = 74;
{B,B,D,B}: y = 94;
{B,B,C,C}: y = 91;
{D,C,C,A}: y = 233;
{C,A,B,A}: y = 133;
{D,A,B,A}: y = 197;
{D,B,B,D}: y = 216;
{C,C,A,C}: y = 163;
{D,D,B,A}: y = 245;
{B,A,D,B}: y = 78;
{A,B,C,D}: y = 28;
{C,C,C,D}: y = 172;
{D,C,A,D}: y = 228;
{A,C,D,A}: y = 45;
{B,D,C,C}: y = 123;
{C,B,A,D}: y = 148;
{B,D,B,B}: y = 118;
{A,D,A,B}: y = 50;
{C,B,B,C}: y = 151;
{A,A,A,A}: y = 1;
{A,A,B,B}: y = 6;
{B,B,B,B}: y = 86;
{A,D,A,A}: y = 49;
{A,A,A,B}: y = 2;
{B,D,D,A}: y = 125;
{C,C,D,B}: y = 174;
{D,A,D,B}: y = 206;
{D,D,B,D}: y = 248;
{A,A,A,D}: y = 4;
{B,A,A,B}: y = 66;
{B,C,C,A}: y = 105;
{B,C,C,C}: y = 107;
{D,D,D,C}: y = 255;
{B,C,D,D}: y = 112;
{A,D,B,C}: y = 55;
{C,C,C,A}: y = 169;
{C,D,B,C}: y = 183;
{A,A,B,D}: y = 8;
{D,C,B,A}: y = 229;
{C,B,D,A}: y = 157;
{A,D,D,C}: y = 63;
{D,A,D,A}: y = 205;
{A,A,B,C}: y = 7;
{A,C,A,B}: y = 34;
{C,B,D,C}: y = 159;
{C,C,D,D}: y = 176;
{D,D,D,A}: y = 253;
{A,B,B,D}: y = 24;
{B,B,C,A}: y = 89;
{B,D,C,A}: y = 121;
{A,B,C,C}: y = 27;
{A,A,D,C}: y = 15;
{A,B,B,A}: y = 21;
{A,D,A,D}: y = 52;
{D,D,C,C}: y = 251;
{C,D,A,B}: y = 178;
{A,A,D,B}: y = 14;
{D,B,D,B}: y = 222;
{A,C,C,A}: y = 41;
{D,D,A,C}: y = 243;
{A,C,D,B}: y = 46;
{B,B,B,D}: y = 88;
{D,B,B,B}: y = 214;
{C,C,B,D}: y = 168;
{A,D,D,A}: y = 61;
{D,A,C,C}: y = 203;
{D,C,A,C}: y = 227;
{C,D,C,D}: y = 188;
{D,B,D,D}: y = 224;
{A,C,D,C}: y = 47;
{B,A,B,D}: y = 72;
{A,B,B,C}: y = 23;
{C,C,D,A}: y = 173;
{D,B,C,C}: y = 219;
{D,B,C,A}: y = 217;
{A,D,C,D}: y = 60;
{B,B,D,A}: y = 93;
{A,D,C,A}: y = 57;
{C,C,A,A}: y = 161;
{C,B,B,D}: y = 152;
{B,B,B,A}: y = 85;
{B,D,A,A}: y = 113;
{D,C,D,A}: y = 237;
{B,C,B,C}: y = 103;
{A,B,C,B}: y = 26;
{C,D,A,D}: y = 180;
{A,D,B,D}: y = 56;
{D,C,A,B}: y = 226;
{D,B,B,C}: y = 215;
{D,A,B,C}: y = 199;
{B,D,A,C}: y = 115;
{C,B,C,D}: y = 156;
{B,D,D,B}: y = 126;
{D,D,C,B}: y = 250;
{D,C,C,D}: y = 236;
{B,C,B,D}: y = 104;
{C,B,C,A}: y = 153;
{C,B,B,B}: y = 150;
{C,D,C,B}: y = 186;
{C,D,C,C}: y = 187;
{A,D,B,B}: y = 54;
{D,C,C,B}: y = 234;
{C,B,D,D}: y = 160;
{A,B,A,D}: y = 20;
{C,C,B,A}: y = 165;
{C,D,D,A}: y = 189;
{C,C,D,C}: y = 175;
{D,B,D,C}: y = 223;
{B,C,A,B}: y = 98;
{C,C,A,B}: y = 162;
{B,C,D,A}: y = 109;
{D,A,B,D}: y = 200;
{B,D,C,D}: y = 124;
{D,D,C,A}: y = 249;
{B,A,C,C}: y = 75;
{A,A,C,B}: y = 10;
{C,A,B,D}: y = 136;
{B,B,C,D}: y = 92;
{D,D,C,D}: y = 252;
{B,C,A,D}: y = 100;
{C,A,C,C}: y = 139;
{C,A,C,D}: y = 140;
{D,C,A,A}: y = 225;
{A,D,C,B}: y = 58;
{D,B,C,D}: y = 220;
{D,C,B,D}: y = 232;
{B,A,C,D}: y = 76;
{B,B,D,D}: y = 96;
{D,D,B,B}: y = 246;
{C,D,A,A}: y = 177;
{D,D,A,B}: y = 242;
{A,A,D,A}: y = 13;
{B,B,A,D}: y = 84;
{B,C,D,C}: y = 111;
{D,A,A,B}: y = 194;
{C,A,B,C}: y = 135;
{D,A,A,C}: y = 195;
{B,B,A,B}: y = 82;
{D,C,D,D}: y = 240;
{B,C,C,D}: y = 108;
{D,B,A,C}: y = 211;
{A,C,D,D}: y = 48;
{D,A,A,A}: y = 193;
{C,A,A,B}: y = 130;
{D,B,A,D}: y = 212;
{D,A,B,B}: y = 198;
{A,C,B,A}: y = 37;
{B,D,B,D}: y = 120;
{C,C,B,C}: y = 167;
{D,B,A,B}: y = 210;
{A,B,A,B}: y = 18;
{B,C,B,B}: y = 102;
{B,B,A,A}: y = 81;
{D,D,A,D}: y = 244;
{A,B,D,B}: y = 30;
{A,C,A,C}: y = 35;
{A,A,C,D}: y = 12;
{B,D,B,C}: y = 119;
{B,C,A,C}: y = 99;
{D,A,C,A}: y = 201;
{B,A,A,D}: y = 68;
{C,A,A,D}: y = 132;
{B,A,C,A}: y = 73;
{C,C,A,D}: y = 164;
{B,D,B,A}: y = 117;
{A,D,D,B}: y = 62;
{B,D,D,C}: y = 127;
{A,B,D,A}: y = 29;
{C,D,B,A}: y = 181;
{B,B,C,B}: y = 90;
{B,D,A,B}: y = 114;
{B,D,D,D}: y = 128;
{C,A,C,A}: y = 137;
{A,A,B,A}: y = 5;
{C,A,D,D}: y = 144;
{D,C,B,C}: y = 231;
{D,A,C,D}: y = 204;
{C,A,A,C}: y = 131;
{C,B,D,B}: y = 158;
{B,A,A,A}: y = 65;
{D,A,D,C}: y = 207;
{D,B,B,A}: y = 213;
{D,B,D,A}: y = 221;
{C,B,C,C}: y = 155;
default: y = 0;
endcase
endmodule