Program optimization

A compiler for converting the source code for a program written in a programming language into machine language and for optimizing said program comprising:

• a graph generator for analyzing a target program and for generating a graph showing the dependencies of operations in said program;
• a graph editing unit for editing said graph and for reducing order restrictions imposed on said operations due to the occurrence of an exception;
• and
• a code reproduction unit for generating program code that reflects said dependencies of said operations of said edited graph;
• wherein said graph editing unit detects an exception generative instruction, which may generate an exception, and an exception generation detection instruction, which branches a process to an exception process when an exception occurrence condition is detected and an exception has occurred, divides said detected exception generation detection instruction into a first instruction, which detects said exception occurrence condition, and a second instruction, which branches said process to said exception process when said exception occurrence condition is detected, and establishes a dependency among the instructions, so that the process is shifted from said first instruction in said graph to said second instruction when said exception occurrence condition is detected, or so that the process is shifted from said first instruction to said exception generative instruction when an exception occurrence condition is not detected.

A compiler for converting the source code for a program written in a programming language into machine language and for optimizing the program comprising:

• an intermediate code generator for converting said source code into editable intermediate code;
• an optimization unit for optimizing said intermediate code;
• and
• a machine language code generator for using said obtained intermediate code to generate machine language code,
• wherein said optimization unit analyzes said intermediate code for said program, transforms said program, within a predetermined range, so that an exception generative instruction that may generate an exception is executed before other instructions, establishes dependencies among the instructions of said program, so that, when an exception has been generated by said exception generative instruction, following the execution of said exception generative instruction the execution of instructions is inhibited, and converts an area in said program, within a predetermined range, so that the occurrence of an exception is detected when an exception is generated by at least one of multiple exception generative instructions, and a process is shifted to a corresponding exception process.

A computer system comprising:

• an input device for receiving a source code of a program;
• a compiler for converting said program and converting said program into a machine language code;
• and
• a processor for executing said machine language code of said program,
• wherein said compiler analyzes said program, detects an exception generative instruction, which may generate an exception, and an exception generation detection instruction, which branches a process to an exception process when an exception occurrence condition is detected and an exception has occurred, divides said detected exception generation detection instruction into a first instruction, which detects said exception occurrence condition, and a second instruction, which branches said process to said exception process when said exception occurrence condition is detected, and establishes a dependency among the instructions, so that the process is shifted from said first instruction to said second instruction when said exception occurrence condition is detected, or so that the process is shifted from said first instruction to said exception generative instruction when an exception occurrence condition is not detected.

A storage medium on which input means of a computer stores a computer-readable program that permits said computer to perform:

• a process for analyzing said program, and detecting an exception generative instruction, which may generate an exception, and an exception generation detection instruction, which branches a process to an exception process when an exception occurrence condition is detected and an exception has occurred;
• a process for dividing said detected exception generation detection instruction into a first instruction, which detects said exception occurrence condition, and a second instruction, which branches said process to said exception process when said exception occurrence condition is detected;
• and
• a process for establishing a dependency among the instructions, so that the process is shifted from said first instruction to said second instruction when said exception occurrence condition is detected, or so that the process is shifted from said first instruction to said exception generative instruction when an exception occurrence condition is not detected.

A program transmission apparatus comprising:

• storage means for storing a program that permits said computer to perform
• a process for analyzing said program, and detecting an exception generative instruction, which may generate an exception, and an exception generation detection instruction, which branches a process to an exception process when an exception occurrence condition is detected and an exception has occurred,
• a process for dividing said detected exception generation detection instruction into a first instruction, which detects said exception occurrence condition, and a second instruction, which branches said process to said exception process when said exception occurrence condition is detected, and
• a process for establishing a dependency among the instructions, so that the process is shifted from said first instruction to said second instruction when said exception occurrence condition is detected, or so that the process is shifted from said first instruction to said exception generative instruction when an exception occurrence condition is not detected;
• and
• transmission means for reading said program from said storage means and transmitting said program.