Program compilation and optimization

An optimization method for optimizing a program to increase processing efficiency comprises the steps of:

• establishing a basic block that includes a Try node for examining, in an object program, a command that may cause an exception process to determine whether an exception process has occurred, and a Catch node for performing an inherent process when an exception process has occurred;
• performing optimization of said object program wherein said basic block is established;
• examining said optimized object program to determine whether a difference in content exists between said command that may cause an exception process and a location whereat said exception process is performed;
• and
• generating in said Catch node of said basic block when a difference exists, a compensation code for compensating for said difference, and a code for, after said compensation code has been obtained, moving program control to said location whereat said exception process is performed.

An optimization method for optimizing a program to increase processing efficiency comprising the steps of:

• dividing code, in an object program, that may cause an exception process into code for determining whether an exception process has occurred and code for actually causing an exception process;
• specifying said code obtained at said division step as branches of a control flow graph;
• designing said control flow graph so that when an exception process occurs, program control is shifted to said code that actually caused said exception process;
• and
• performing said optimization process for said object program that has been modified.

A computer executable program comprising:

• a function for examining a command, in said computer program, that may cause an exception process, to determine whether an exception process has occurred;
• a function for running an exception process;
• and
• a function for, when an exception process has occurred, shifting program control to a portion whereat said exception process is run, and for, when a difference in content exists between the point of origin of said exception process and said portion whereat said exception process is run, compensating for said difference before program control is shifted to said portion whereat said exception process is run.

A program transmission apparatus comprising:

• storage means for storing a program that permits a computer to perform
• a process for preparing a basic block that includes a portion for examining a command, in an object program, that may cause an exception process, in order to determine whether an exception process has occurred, and that includes a command for, when an exception process has occurred, moving program control to a portion whereat said exception process is performed, and
• a process for, when a difference in content exists between the point of origin of said exception process and said portion whereat said exception process is performed, generating in said basic block compensation code for compensating for said difference;
• and
• transmission means for reading said program from said storage means and for transmitting said program.