Instructions missing for augmentedAddition and augmentedSubtraction

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RISC-V Instruction Set Manual

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Instructions missing for augmentedAddition and augmentedSubtraction #482

Open marioxcc opened 4 years ago

marioxcc commented 4 years ago

IEEE 754-2019 includes 3 new recommended operations to speed-up multi-word arithmetic and reproducible summations (e.g.: linear algebra libraries): augmentedAddition, augmentedSubtraction and augmentedMultiplication. The later can be multiplied with FMA. The first 2 require each an additional instruction for efficient implementation. See “Augmented Arithmetic Operations Proposed for IEEE 754-2018”.

aswaterman commented 4 years ago

We agree instructions for these operations should be considered as part of an eventual new floating-point extension.