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compiler idiom

A pattern of instructions that a compiler always uses for one C++ construct, so recognizing the pattern tells you the construct.

A compiler idiom is a recurring instruction sequence characteristic of a source construct under a given compiler and optimization level: rotated loops, bounds check plus jump table for switch, vptr load plus indirect call for a virtual call, multiply-high plus shifts for division by a constant, setcc/cset for a bool, cmov/csel for a select, rep movsb or vector moves for an inlined memcpy.

See also

multiply-high strength reduction
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