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E.10.3.2 Part selects</div>
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logic. Array slices are not supported for unpacked arrays. Additionally, 64-bit wide part select can be read as a single value of type unsigned long long. </p>
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Functions for part selects only allow access (read/write) to a narrow subrange of up to 32 bits. A canonical representation shall be used for such narrow vectors. If the specified range of part select is not fully contained within the normalized range of an array, the behavior is undetermined. </p>
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For the convenience, bit type part selects are returned as a function result. In addition to a general function for narrow part selects (<= 32-bits), there are two specialized functions for 32 and 64 bits. </p><div class="Element170">
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<div class="Element13"><div class="Element12" id="code01095"><pre class="Element12">/*
* functions for part select
*
* a narrow (<=32 bits) part select is copied between
* the implementation representation and a single chunk of
* canonical representation
* Normalized ranges and indexing [n-1:0] are used for both arrays:
* the array in the implementation representation and the canonical array.
*
* s=source, d=destination, i=starting bit index, w=width
* like for variable part selects; limitations: w <= 32
*
* In part select operations, the data is copied to or from the
* canonical representation part (’chunk’) designated by range [w-1:0]
* and the implementation representation part designated by range [w+i-1:i].
*/</pre></div></div>
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NOTE—For the sake of symmetry, a canonical representation (i.e., an array) is used both for bit and logic, although a simpler int can be used for bit-part selects (<= 32-bits): </p><div class="Element170">
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<div class="Element13"><div class="Element12" id="code01096"><pre class="Element12">/* canonical <-- actual */
void svGetPartSelectBit(svBitVec32* d, const svBitPackedArrRef s, int i,
int w);
svBitVec32 svGetBits(const svBitPackedArrRef s, int i, int w);
svBitVec32 svGet32Bits(const svBitPackedArrRef s, int i); // 32-bits
unsigned long long svGet64Bits(const svBitPackedArrRef s, int i); // 64-bits
void svGetPartSelectLogic(svLogicVec32* d, const svLogicPackedArrRef s, int i,
int w);
/* actual <-- canonical */
void svPutPartSelectBit(svBitPackedArrRef d, const svBitVec32 s, int i,
int w);
void svPutPartSelectLogic(svLogicPackedArrRef d, const svLogicVec32 s, int i,
int w);</pre></div></div>
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