Patent ID: 9569188
Date: 2017-02-14
CPC Classifications: G06F

Claim:
1. A method of compiling source code to reduce run-time execution of vector element reverse operations, the method comprising: identifying, by a compiler, a first loop and a second loop in a computer program, wherein the first loop is embedded within the second loop; identifying, by the compiler, at least one vector element reverse operation within the first loop; analyzing, by the compiler, a dataflow graph containing that at least one vector element reverse operation within the first loop, including determining whether all vector operations in a portion of the dataflow graph including the first loop are lane-insensitive and determining whether all vector operations in the portion of the dataflow graph containing the first loop are lane-adjustable; and responsive to the analysis, replacing, by the compiler, the vector element reverse operations from the first loop by placing the vector element reverse operations inside the second loop; moving, by the compiler and within the second loop, a plurality of vector element reverse operations to the perimeter of the first loop; and for each pair of vector element reverse operations moved to the perimeter of the first loop in which a result of one of the vector element reverse operations in the pair is the source of the other vector element reverse operation in the pair: removing at least one of the vector element reverse operations in the pair.