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Also present is unusual (variable-bit-length) byte load and store instructions that use ''byte pointers'' for memory operands: in modern terminology these are bit-field insert and extract. In addition to a word address, the bit length (S) and the bit offset (P) of the byte from which to load or into which to store are specified. These instructions can specify a byte size of 0-36, but a byte may not straddle a word boundary.{{sfn|pdp10|pages=2{{hyp}}85-2{{hyp}}89|loc=Byte manipulation|}} The string manipulation,{{sfn|pdp10|pages=2{{hyp}}91-2{{hyp}}99|loc=2.12 String Manipulation|}} BCD/binary conversion,{{sfn|pdp10|pages=2{{hyp}}98-2{{hyp}}103|loc=2.13 Decimal Conversion|}} and string editing{{sfn|pdp10|pages=2{{hyp}}104-2{{hyp}}112|loc=2.14 String Editing|}} instructions in later models use byte pointers and have the same restrictions.
==GE600 series==
The [[GE600 series]] and its successors had Gray-to-binary conversion, which [[Gray_code#Converting_to_and_from_Gray_code|requires costly recursion]]: converting a 64-bit Gray code to binary would require execution of hundreds of instructions. Binary-to-Gray is simply {{code|x^(x>>1)}} and does not justify a dedicated instruction. Gray coding has significant [[Gray_code#History_and_practical_application|practical applications]]
=== ARM ===
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