Code generation method and information processing apparatus

A code generation method, executed by a computer, for generating, from a first code, a specific instruction for performing a same type of operation on different data in parallel by combining two or more instructions included in the first code, and generating a second code including the specific instruction, the code generation comprising:

• generating first and second operation trees representing a dependency relationship among instructions included in the first code, computing a first operation sequence by arranging operations specified by instructions of the first operation tree in an order that matches a structure of the first operation tree, and computing a second operation sequence by arranging operations specified by instructions of the second operation tree in an order that matches a structure of the second operation tree;
• computing one or more longest operation subsequences of operation subsequences common to the first and second operation sequences, which appear by deleting one or more operations from one or both of the first and second operation sequences;
• and
• evaluating, for each of two or more longest operation subsequences, when computed, utilization of computing resources used for executing combinations of instructions of the first and second operation trees corresponding to operations included in said each longest operation subsequence, and selecting a combination pattern of instructions indicated by one of the two or more longest operation subsequences based on results of the evaluating.

An information processing apparatus comprising:

• a storage unit configured to store a first code, and a second code including a specific instruction for performing a same type of operation on different data in parallel;
• and
• a processor configured to generate the second code from the first code by combining two or more instructions included in the first code,
• wherein the processor generates first and second operation trees representing a dependency relationship among instructions included in the first code, computes a first operation sequence by arranging operations specified by instructions of the first operation tree in an order that matches a structure of the first operation tree, and computes a second operation sequence by arranging operations specified by instructions of the second operation tree in an order that matches a structure of the second operation tree,
• computes one or more longest operation subsequences of operation subsequences common to the first and second operation sequences, which appear by deleting one or more operations from one or both of the first and second operation sequences, and
• evaluates, for each of two or more longest operation subsequences, when computed, utilization of computing resources used for executing combinations of instructions of the first and second operation trees corresponding to operations included in said each longest operation subsequence, and selects a combination pattern of instructions indicated by one of the two or more longest operation subsequences based on results of the evaluating.