1995-11-29
1998-08-18
Voeltz, Emanuel Todd
395588, G06F 945
Patent
active
057970130
ABSTRACT:
A compiler facilitates efficient unrolling of loops and enables the elimination of extra branches from the loops, including the elimination of conditional branches from unrolled loops with early exits. Unrolling also enhances other optimizations, such as prefetch, scalar replacement, and instruction scheduling. The unroll factor is calculated to determine the amount of loop expansion and the optimum location to place compensation code to complete the original loop count, i.e. before or after the unrolled loop. The compiler is applicable, for example, to modern RISC architectures, where the latency of memory references and branches is higher than that of integer and floating point arithmetic instructions.
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Mahadevan Uma
Shah Lacky
Chaki Kakali
Hewlett--Packard Company
Todd Voeltz Emanuel
LandOfFree
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