2. The module generating apparatus according to claim 1 , wherein the macroblocking analyzing unit appends, to a number identifying a variable for a statement in each block, a virtual portion representing a number unique in the statement, the virtual portion being appended as the appendant information and to express the number for identifying the variable by a combination of a lower portion representing a number unique in the source code entirely and an upper portion made up of the virtual portion.
2. The module generating apparatus according to claim 1 , wherein the macroblocking analyzing unit appends, to a number identifying a variable for a statement in each block, a virtual portion representing a number unique in the statement, the virtual portion being appended as the appendant information and to express the number for identifying the variable by a combination of a lower portion representing a number unique in the source code entirely and an upper portion made up of the virtual portion. 3. The module generating apparatus according to claim 2 , wherein the identical portion merging/restructuring unit performs comparison between nodes in the ancestor block and between nodes in the descendant block by identifying a variable based on the virtual portion.