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31.10 Variables (supersedes IEEE 1364-2001 section 26.6.8)</div>
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NOTES </p>
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1) A var select is a word selected from a variable array. </p>
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2) The boolean property vpiArray shall be TRUE if the variable handle references an array of variables, and FALSE otherwise. If the variable is an array, iterate on vpiVarSelect to obtain handles to each variable in the array. </p>
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3) To obtain the members of a union and structure, see the relations in Section 31.21 </p>
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4) The range relation is valid only when vpiArray is true. When applied to array vars this relation returns only unpacked ranges. When applied to logic and bit variables, it returns only the packed ranges. </p>
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5) vpi_handle (vpiIndex, var_select_handle) shall return the index of a var select in a 1-dimensional array. vpi_iterate (vpiIndex, var_select_handle) shall return the set of indices for a var select in a multidimensional array, starting with the index for the var select and working outward </p>
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6) vpiLeftRange and vpiRightRange shall only apply if vpiMultiArray is not true, i.e. if the array is not multi-dimensional. </p>
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7) A variable handle of type vpiArrayVar represents an unpacked array. The range iterator for array vars returns only the unpacked ranges for the array. </p>
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8) If the variable has an initialization expression, the expression can be obtained from vpi_handle(vpiExpr, ar_handle) </p>
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9) vpiSize for a variable array shall return the number of variables in the array. For non-array variables, it shall return the size of the variable in bits. For unpacked structures and unions the size returned indicates the number of fields in the structure or union. </p>
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10) vpiSize for a var select shall return the number of bits in the var select. This applies only for packed var select. </p>
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11) Variables whose boolean property vpiArray is TRUE do not have a value property. </p>
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12) vpiBit iterator applies only for logic, bit, packed struct, and packed union variables. </p>
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13) vpi_handle(vpiIndex, var_bit_handle) shall return the bit index for the variable bit. vpi_iterate(vpiIndex, var_bit_handle) shall return the set of indices for a multidimensional variable bit select, starting with the index for the bit and working outwards </p>
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14) cbSizeChange will be applicable only for dynamic and associative arrays. If both value and size change, the size change callback will be invoked first. This callback fires after size change occurs and before any value changes for that variable. The value in the callback is new size of the array. </p>
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15) The property vpiRandType, returns the current randomization type for the variable, which can be one of vpiRand, vpiRandC, and vpiNotRand. </p>
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16) vpiIsRandomized is a property to determine whether a random variable is currently active for randomization. </p>
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17) When the vpiMember property is true, it indicates that the variable is a member of a parent struct or union variable. See also relations in Section 31.21 </p>
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18) If a variable is an element of an array, the vpiIndex iterator will return the indexing expressions that select that specific variable out of the array. </p>
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19) Note that: </p>
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logic var == reg </p>
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var bit var == reg bit </p>
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array var == reg array </p>
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20) The properties vpiScalar and vpiVector are applicable only to packed struct vars, packed union vars, bit vars and logic vars. These properties return false for all other objects.</p></div>
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