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20.4.3 Wildcard specification of coverage point bins</div>
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By default, a value or transition bin definition can specify 4-state values. When a bin definition includes an X or Z, it indicates that the bin count should only be incremented when the sampled value has an X or Z in the same bit positions, i.e., the comparison is done using ===. The wildcard bins definition causes all X, Z, or ? to be treated as wildcards for 0 or 1 (similar to the =?= operator). For example: </p><div class="Element170">
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<div class="Element13"><div class="Element12" id="code00891"><pre class="Element12">wildcard bins g12_16 = { 4’b11?? };</pre></div></div>
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The count of bin g12_16 is incremented when the sampled variable is between 12 and 16: </p><div class="Element170">
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<div class="Element13"><div class="Element12" id="code00892"><pre class="Element12">1100 1101 1110 1111</pre></div></div>
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Similarly, transition bins can define wildcard bins. For example: </p><div class="Element170">
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<div class="Element13"><div class="Element12" id="code00893"><pre class="Element12">wildcard bins T0_3 = (2’b0x => 2’b1x);</pre></div></div>
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The count of transition bin T0_3 is incremented for the following transitions (as if by (0,1=>2,3)): </p><div class="Element170">
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<div class="Element13"><div class="Element12" id="code00894"><pre class="Element12">00 => 10 00 => 11 01 => 10 01 => 11</pre></div></div>
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A wildcard bin definition only consider 2-state values; sampled values containing X or Z are excluded. Thus, the range of values covered by a wildcard bin is established by replacing every wildcard digit by 0 to compute the low bound and 1 to compute the high bound.</p></div>
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