Rosenzweig: Reverse-engineering the Mali G78

Alyssa Rosenzweig goesinto the details of the reverse-engineering of the Mali "Valhall" GPUinstruction set.

Valhall linearizes Bifrost, removing the Very Long Instruction Wordmechanisms of its predecessors. Valhall replaces the compiler'sstatic scheduling with hardware dynamic scheduling, tradingadditional control hardware for higher average performance. Thatmeans padding with no operation" instructions is no longerrequired, which may decrease code size, promising betterinstruction cache use.

A document describing the instruction set has been released, along with anassembler and disassembler.