30 results about "Assignment" patented technology

The invention discloses an interprocedural static slice extracting method based on an idUCf quinary structure. The extracting method comprises the following steps: expressing static slices in a procedure according the type of variables and the positions of the static slices, and establishing an expression; according to the assignment values of the variables, performing backward type searching in the expression; extracting the static slices of which the variable values are equal to the assignment values. The extracting method disclosed by the invention can increase the utilization ratio of computer spaces and times, and improves the extracting efficiency of the slices.

Methods and systems are provided for reducing the number of copies in execution of routines written in a procedural language using assignment-by-value semantics. During routine assembly, each statement in a routine is classified as either copy-sensitive or non-copy-sensitive, depending on the operations that the statement contains. During routine execution, a lazy copy strategy is used to determine when a variable should be copied: copying is not performed on variable assignments, but is delayed until the variable is used in a copy-sensitive statement. If a variable is never used in a copy-sensitive statement, it will not be copied, thus saving computation time and storage.

The invention discloses a method for realizing definite software operating time in a single task operating environment, which is characterized by comprising the following steps of: (1) programming a function meeting requirements by using a conventional programming method; (2) dividing external input, external output and algorithm of the function definitely; (3) establishing a local variable for the external output; (4) finding out all switch statements in the function; (5) establishing local variables for the external output of all the switch statements; (6) cutting the programs of all the switch statements out of the switch statements, and modifying the output of the switch statements into the local variables of the output of the switch statements; (7) in the switch statements, adding the local variables of the output of the switch statements to an assignment statement output by a switch statement operation result and an assignment statement for a global variable; (8) adding the switch statement operation result to follow-up program operation; (9) assigning the local variable of the external output to the external output; and finally (10) modifying functions called in the program. The invention can ensure that the operating time of the same function is definite without change when outputs and routes are different.

An extracting unit randomly extracts a block from among the blocks of instruction strings constituting the byte code of a first program and, at the time of execution of the first program, extracts the blocks which are invariably executed before the randomly-extracted block. A dividing unit randomly divides, into a plurality of blocks, the instruction strings constituting the byte code of a second program which enables detection of tampering of the first program. An inserting unit inserts the plurality of blocks, which are obtained by division by the dividing unit, at different positions in the block extracted by the extracting unit, while maintaining the execution sequence written in the second program.