A new speculative addition architecture suitable for two´s complement operations

Existing architectures for speculative addition are all based on the assumption that operands have uniformly distributed bits, which is rarely verified in real applications. As a consequence, they may be disadvantageous for real-world workloads, although in principle faster than standard adders. To address this limitation, we introduce a new architecture based on an innovative technique for speculative global carry evaluation. The proposed architecture solves the main drawback of existing schemes and, evaluated on real-world benchmarks, it exhibits an interesting performance improvement with respect to both standard adders and alternative architectures for speculative addition.