JPS63204340A - Circuit for measuring covering rate of program - Google Patents

Abstract

PURPOSE:To estimate the detail operation of a microprogram, by providing a pass memory and a count value arithmetic circuit, and storing the number of times of passing of each address of the microprogram. CONSTITUTION:A pass memory 103, after being cleared to all 0s at the time of starting up, stores a counted value which represents the number of times of passing in an address corresponding to each address of a memory 101 for storing the microprogram. The count value arithmetic circuit 104 reads out the counted value of the address from the pass memory 103 by the readout address of the memory 101 for storing the microprogram held in an address register 102, and adds (1) on the value, and rewrites an added value on the same address again. In such a way, it is possible to find the number of times of passing of a microinstruction with the same address by analyzing the value of the pass memory, and to estimate the detail operation of the microprogram.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a microprogram-controlled information processing device.

[Conventional technology]

Most of the information processing devices currently in operation are controlled by microprograms.

Conventionally, there are few techniques for measuring the coverage rate of microprograms, and even if there were, there would be a flag with an initial value of "On" for each address in the memory for storing microprograms, and when a microinstruction is executed, the The idea was to set the flag corresponding to the address to ``1''.

[Problem that the invention seeks to solve]

The conventional information processing device described above only sets the flag associated with the 7th address of the executed microinstruction to '1', so the address of the executed microinstruction can be recognized, but the microinstruction at the same address It is not known how many times an instruction has been executed, and therefore the detailed operation of the microprogram cannot be estimated just by looking at the flag states.

[Means for solving problems]

The microprogram coverage measurement circuit of the present invention reads a path memory addressed by the contents of an address register that holds a read address of a program storage memory, and reads the path memory according to the contents of the address register, updates the value, and then updates the path memory to the same address as the address register. It has a count value arithmetic circuit for writing into.

[For production]

Therefore, you can find out how many times a microinstruction at the same address has been executed by analyzing the path memory value.
Detailed operations of microprograms can be estimated.

〔Example〕

Next, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a diagram showing the configuration of one embodiment of the microprogram coverage measurement circuit of the present invention. To simplify the explanation, subroutines will not be used. The address calculation circuit 105 adds t'' to the address of the address register 102 and sends it to the selector 107.
Holds the next address written in the microinstruction read from 01. Selector 10? is one address calculation circuit l
O5 and the address from the next address register 10B are selected and sent to the address register 102. Pass memory 1
03 is cleared to all 0s at system start-up, and then a count value indicating the number of times the address has been passed is stored in an address corresponding to each address in the microprogram storage memory 101. The count value calculation circuit 104 reads the path memory 1 based on the read address of the microprogram storage memory 101 held in the address register 102.
Read the count value of that address from 03 and set 1 to it.
Add ″′ and write the added value back to the same address.

FIG. 2 is a timing chart of the circuit of FIG. After the count value a is read from the 7th address A of the path memory 103 indicated by the address register 102, it is added by l and written to the same address A. After the count value a is read from the primary address A+1, it is added by l. same address A+
After the count value C is written to 1 and read from the next address A+2, it is written to the same address A+2 to which l is added.

In this way, the number of times each address of the microprogram has been passed is stored in the path memory 103 at an address relative to the above address.

[Effects of the Invention] - As explained above, the present invention provides a path memory and a count value calculation circuit, and stores the number of times each address of the microprogram has been passed for each of the seven addresses, thereby making it possible to cover the entire microprogram. In addition to being able to measure the rate, by analyzing the count value of each address, it is possible to determine the number of times each of multiple sequences in a microprogram is executed and estimate the detailed behavior of the microprogram. There is an effect that can be achieved.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the configuration of an embodiment of the microprogram coverage measurement circuit of the present invention, and FIG. 2 is a timing chart showing how the number of times each address of the microprogram is passed is counted up. 101...Memory for storing microprograms,
102...Address register, 103...
...Pass memory. 104... Count value calculation circuit, 105---
---Address calculation circuit, lOB...Next address register, 10? ······selector.

Claims (1)

[Claims] A microprogram-controlled information processing device comprising: a path memory that is addressed by the contents of an address register that holds a read address of a microprogram storage memory; A microprogram coverage measurement circuit having a count value calculation circuit that updates and writes to the same address.