Fujitsu Corporation

Tadashi Nakahira

Masakazu Hayashi

Masatoshi Haraguchi

A compiling processing apparatus which compiles a program operating in a computer having a cache memory. This apparatus collects memory access data for the cache memory, analyzes confliction relationships between them, determines whether or not an instruction for confliction memory access data relocates, relocates the instruction if relocation is possible, and reduces the number of cache miss. Further, this apparatus recognizes memory access data in a continuous area, audits recognized memory access data alignment, generates an instruction of pair-load/pair-store, and reduces the number of memory accesses.

Compiling processing apparatus

The entire space of a loop is analyzed for dependencies between target array elements so that dependency ID's are assigned to the target array elements. Optimization is carried out on the basis of the dependency ID's. Dependency ID's covering dependency for an arbitrary turn of the loop are reassigned to the target array elements that have been subjected to optimization, whereupon a further optimization is carried out. An examination for identifying overlappings is carried out on the basis of the dependency ID assigned to the target array elements so that instruction scheduling is carried out.

Loop optimization compile processing method

An object of the present invention is to realize a compiling apparatus producing an object program which can be executed at a high speed. In a compiling apparatus according to the present invention, an aliasing address comparison instruction generating unit inserts a instruction to compare the two memory addresses of each pair of data expressions whose overlap is judged to be obscure, generates a plurality of paths defined by combinations of conditions whether or not memory addresses of data expressions of each pair overlap, and generates a instruction to branch to one of the paths according to a comparison result obtained by the instruction in an execution of a compiled program, and an optimization unit for respectively optimizing the paths. When the object program is executed, one path corresponding to a practical condition is selected from the plurality of paths, and only the selected path is executed.

Growing community of inventors

Kawasaki, Japan

Tadashi Nakahira