System Verilog Assertions - dynamic delays

Ben cohen provided the code for dynamic delays in verification academy forum.

I have just pasted it here...

Link :

https://verificationacademy.com/forums/systemverilog/sva-package-dynamic-and-range-delays-and-repeats

 Code :

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// Ben Cohen December 13, 2018 package sva_delay_repeat_range_pkg; // int d1, d2; // bit a, b, c=1'b1; // sequence q_s; a ##1 c; endsequence // sequence my_sequence; e ##1 d[->1]; endsequence //---------------------------------------------------------------- // ****** DYNAMIC DELAY ##d1 ********** // Application: $rose(a) |-> q_dynamic_delay(d1) ##0 my_sequence; sequence q_dynamic_delay(count); int v; (1, v=count) ##0 first_match((1, v=v-1'b1) [*0:$] ##1 v<=0); endsequence //---------------------------------------------------------------- // ****** DYNAMIC DELAY RANGE ##[d1:d2] ********** //##[d1:d2] ##0 b; // NO sequence followng the "b" // $rose(a) |-> q_dynamic_delay_range(d1, d2, b)) // and b[->1] ##1 my_sequence; // $rose(a) ##0 q_dynamic_delay_range(d1, d2, b) |-> my_sequence; sequence q_dynamic_delay_range(int d1, d2, bit b); int v1, vdiff; (1, v1=d1, vdiff=d2-d1) ##0 q_dynamic_delay(v1) ##0 first_match((1, vdiff=vdiff - 1)[*0:$] ##1 (b || vdiff<=0)) ##0 b; endsequence //---------------------------------------------------------------- // ****** DYNAMIC REPEAT q_s[*d1] ********** // Application: $rose(a) |-> q_dynamic_repeat(q_s, d1) ##1 my_sequence; sequence q_dynamic_repeat(q_s, count); int v=count; (1, v=count) ##0 first_match((q_s, v=v-1'b1) [*1:$] ##0 v<=0); endsequence //---------------------------------------------------------------- // ****** DYNAMIC REPEAT RANGE q_s[*d1:d2] ********** // Application: $rose(a) |-> (q_dynamic_repeat_range(q_s, d1, d2, b) // and b[->1] ##1 my_sequence // use the same "b" // $rose(a) ##1 q_dynamic_repeat_range(q_s, d1, d2, b) |-> my_sequence; sequence q_dynamic_repeat_range(sequence q_s, int r1, r2, bit b); int v, diff; (1, v=r1, diff=r2-r1) ##0 q_dynamic_repeat(q_s, v) ##1 // repeat to r1 first_match((q_s, diff=diff-1'b1) [*0:$] ##1 (b || diff<=0 )) ##0 b; endsequence endpackage import uvm_pkg::*; `include "uvm_macros.svh" import sva_delay_repeat_range_pkg::*; module top; timeunit 1ns; timeprecision 100ps; bit clk, a, b, c=1, w; int d1=2, d2=5; sequence q_s; a ##1 c; endsequence sequence my_sequence; a ##1 w[->1]; endsequence default clocking @(posedge clk); endclocking initial forever #10 clk=!clk; // ****** DYNAMIC DELAY ##d1 ********** // Application: $rose(a) |-> q_dynamic_delay(d1) ##0 my_sequence; ap_dyn_delay: assert property(@ (posedge clk) $rose(a) |-> q_dynamic_delay(d1) ##0 my_sequence); ap_fix_delay: assert property(@ (posedge clk) $rose(a) |-> ##2 my_sequence); // ****** DYNAMIC DELAY RANGE ##[d1:d2] ********** //##[d1:d2] ##0 b; // NO sequence followng the "b" // $rose(a) |-> q_dynamic_delay_range(d1, d2, b)) // and b[->1] ##1 my_sequence; // $rose(a) ##0 q_dynamic_delay_range(d1, d2, b) |-> my_sequence; ap_dly_rng: assert property(@ (posedge clk) $rose(a) |-> q_dynamic_delay_range(d1, d2, b) and b[->1] ##1 my_sequence); ap_2to5: assert property(@ (posedge clk) $rose(a) |->(##[2:5] b) and b[->1] ##1 my_sequence); ap_dly_rng_antc: assert property(@ (posedge clk) $rose(a) ##0 q_dynamic_delay_range(d1, d2, b) |-> my_sequence); ap_2to5_antc: assert property(@ (posedge clk) $rose(a) ##0 first_match(##[2:5] b) |-> my_sequence); //------------------------------------------------------------------ // ****** DYNAMIC REPEAT q_s[*d1] ********** // Application: $rose(a) |-> q_dynamic_repeat(q_s, d1) ##1 my_sequence; ap_rpt: assert property(@ (posedge clk) $rose(a)|-> q_dynamic_repeat(q_s, d1) ##1 my_sequence); ap_rpt2: assert property(@ (posedge clk) $rose(a)|-> q_s[*2] ##1 my_sequence); // ****** DYNAMIC REPEAT RANGE q_s[*d1:d2] ********** // Application: $rose(a) |-> (q_dynamic_repeat_range(q_s, d1, d2, b) // and b[->1] ##1 my_sequence // use the same "b" // $rose(a) ##1 (q_dynamic_repeat_range(q_s, d1, d2, b) |-> my_sequence; ap_rpt_rng: assert property(@ (posedge clk) $rose(a) |-> q_dynamic_repeat_range(q_s, d1, d2, b) and b[->1] ##1 my_sequence); ap_rpt_2to5: assert property(@ (posedge clk) $rose(a) |-> first_match(q_s[*2:5] ##1 b) and b[->1] ##1 my_sequence); ap_rpt_rng_antc: assert property(@ (posedge clk) $rose(a) ##1 q_dynamic_repeat_range(q_s, d1, d2, b) |-> my_sequence); ap_rpt_2to5_antc: assert property(@ (posedge clk) $rose(a) ##1 first_match(q_s[*2:5] ##1 b) |-> my_sequence); initial begin repeat(1000) begin @(posedge clk); #2; if (!randomize(a, b, c, w) with { a dist {1'b1:=1, 1'b0:=1}; b dist {1'b1:=1, 1'b0:=1}; c dist {1'b1:=1, 1'b0:=1}; w dist {1'b1:=1, 1'b0:=1}; }) `uvm_error("MYERR", "randomize error"); end #1; repeat(1500) begin @(posedge clk); #2; if (!randomize(a, b, c, w) with { a dist {1'b1:=1, 1'b0:=2}; b dist {1'b1:=3, 1'b0:=2}; c dist {1'b1:=1, 1'b0:=1}; w dist {1'b1:=3, 1'b0:=1}; }) `uvm_error("MYERR", "randomize error"); end $stop; end endmodule