1. A computer system for speculatively executing instructions, comprising: means for grouping instructions related by data dependencies and control dependencies into a plurality of sets, each set including a plurality of instructions, said plurality of instruction of each set arranged in a normal execution order, said plurality of instructions include a store instruction followed in the normal execution order by a load instruction, said load instruction and said store instruction are related by said data dependencies if a validity of data used by said load instruction of said particular set is unresolvable; means for reordering the plurality of instructions of a particular set out of the normal execution order to accelerate execution of said plurality of instructions, said means for reordering further comprising means for moving said load instruction before said store instruction; means for executing said sets in parallel with one and another in a speculative state of the computer system before said data dependencies and control dependencies are resolved to generate speculative data; means for determining if said particular set is subject to an exception condition while executing in said speculative state; and means, responsive to detecting said exception condition, for repeating execution of the plurality of instructions of said particular set in a real state of the computer system to process said exception condition.