JPS60542A - Program tracing device - Google Patents

Abstract

PURPOSE:To perform a program tracing process at a high speed, by appointing the writing in and reading out from a memory under an endless condition by one point by means of a counter and connecting the memory with a data bus through a gate. CONSTITUTION:When the address alphaAB of a program tracing device 10 is transmitted to an address bus (AB) 11 from a computer 9, a decoder 20 detects this and makes a signal 41 high level. When a strobe signal (SBT) 14 successively becomes high level, an AND gate 40 is turned on and, since a read/write signal (R/W) 13 is low level, another AND gate 60 is turned on. When the AND gate 60 is turned on, a gate 80 is opened and data are transmitted to a memory 90 from a data bus (DB) 12. A counter 30 indicates a memory writing point and increases the writing point one by one whenever the writing is made. Thus the counter 30 appoints endlessly the writing point in the memory. Since the R/W13 is high level when data are read out from the memory 90, an AND gate 50 is turned on and the data of the memory 90 are sent to the computer 9 through a gate 70 and DB12.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a program tracing device that provides troubleshooting information to an inspector by tracing the execution progress of a program.

[R scene of invention]

FIG. 1 shows a typical operating system process for interrupts. Figure 1 shows the flow of processing from when an interrupt occurs while task 8 is being executed, task A is suspended, the operating system is started, and task A is restarted after servicing the interrupt. show.

The operating system first executes a program trace process 100 to record interrupt information. The interrupt information requires at least the following information and spans multiple words.

l) Interruption factor 11) Task interruption point m>computer status information +V) Contents of various registers and counters (block 5100 of the flowchart in FIG. 1).

It also executes program trace processing to record task return information when the operating system returns to a task. Task return information also spans multiple words.
(Block A 120).

The information recorded by these program trace processes is information necessary for tracing the progress of computer processing. In particular, it is impossible to trace interrupts that occur at any time and at any location without this information.

However, the program trace processing time occupies 40% of the total processing time in the operating system, and is a cause of automatic head increase. In order to reduce overhead, there is a sense of security in speeding up program trace processing.

Figure 2 shows branch processing often used in programs. Second
In the figure, when the system conditions 200 are A, B, and C, processes are executed for A, B, and C, respectively. That is, at the time of 210,220, at the time of B, at the time of 230.240, at the time of C,
250, 260° flowchart is shown. System conditions may be A, B, or C.
To trace the progress of computer processing, it is necessary to record branch information.

In addition to branching, the important points of the program are jumps,
These include subroutine calls and returns from subroutines. To fully trace the progress of a computer's processing,
It is necessary to record all information when passing through these important points. However, since executing the program trace process increases the processing time of the computer, it has been impossible to execute the program trace process except for particularly important points in programs that require high-speed processing.

In order to perform tracing completely, it is necessary to simplify the program tracing process and shorten the processing time.

Next, general program tracing processing will be explained with reference to FIGS. 3 and 4. FIG. 3 shows the area and FIG. 4 shows the processing flow.

The recording area is divided by a starting address α of the recording area and a final address γ of the recording area, and recording is performed sequentially from the starting address α. Next, the address for recording is recording address β.

In the program trace processing, first, it is checked whether the number of words in the remaining area is greater than or equal to the number of recorded words (block 300 in the flowchart of FIG. 4).

If the number of words in the remaining area is less than the number of recorded words, the remaining area is cleared to zero.Block A 310
), sets the start address α of the recording area to the recording address β (block A 320 ).

Information is recorded sequentially from the recording address β for the necessary number of words (block A 330 ).

Finally, add the recorded address by the number of recorded words (
Block cup 340).

The above is the processing content of program trace, and the preprocessing (block A300°310.3
20) accounts for approximately 50%, and recording processing (block A 33)
0) accounts for approximately 30%, and post-processing (block A 340
) account for approximately 20%.

Therefore, a reduction in preprocessing time leads to a reduction in program trace processing time.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a program tracing device for performing high-speed program tracing processing for endlessly recording information when a program passes the 1'9 point or interrupt information when an interrupt occurs.

[Summary of the invention]

A feature of the present invention is that in program trace processing, information recording differs depending on each piece of information (interrupt information, branch information, jump information, subroutine call information, subroutine return information, etc.), so it provides versatility. The goal is to perform software processing, convert all remaining processing to hardware, and execute it at high speed with simple hardware.

[Embodiment of the Invention] Hereinafter, an embodiment of the present invention will be described with reference to FIGS.

FIG. 5 shows a circuit diagram of one embodiment of the present invention. The glogram tracing device 10 has a γ' dress path 11 (hereinafter A
It is connected to the computer 9 by a data bus 112 (hereinafter referred to as DB), a read/write signal 13 (hereinafter referred to as R/W), and a strobe signal 14 (hereinafter referred to as STB).

The program trace device 1o includes a decoder 20, a counter 30, an AND gate 40, 50, 60, a gate 70,
80. It is composed of a memory 9o.

In the figure, 31 is a bus, and 51 is a signal.

FIG. 6 shows a time chart when data is written from the computer 9 to the memory 9o, and the operation of the program tracing device 1° will be explained using this time chart. A
When the address αmB of the program trace device 1o is transmitted on the BII, the decoder 20 detects the address αmB and sets the signal 21 to the 1H level.Subsequently, the 5T
When B14 goes to ``HH level, AND gate 4o goes to O.
N, the signal 41 becomes ``(level''. Since R/W 13 is at 1L level, ND game) 60 turns ON,
When the signal 61 becomes @H level, the gate 80 turns on.
DATA is transmitted to the memory 90 via the DB12-+gate 8o→bus 81. The count value β of the counter 30 indicates the data writing point of the memory 90. 2
, DAI is written to point one person B. When the 5TB14 reaches the ``''LL level, the signal 41 goes to the ``''LL level, and at the same time the write operation to the memory 90 is completed, the contents of the counter are incremented by +1.

FIG. 7 shows the relationship between the areas of the memory 90 and count values. The capacity of the memory 90 and the count range of the counter 30D have the same size, and the counter value '09 of the counter 30 (the initial value of the counter) corresponds to the initial point of the memory 90, and the count value - maximum'' (the final value of the counter) ) corresponds to the final point. Count 1 indicates the convolution into the memory and the read point. When the count value exceeds the maximum value, the counter 3o carries over and the count value returns to 10''.

FIG. 8 shows a time chart when reading data from the memory 90. Since the R/W 13 is at ``HH level'' during reading, the AND gate 50 is turned on and the signal 51 becomes 1.
At "H level", DA'l'A' is transmitted to the computer via bus 81 → gate 70 → DB12.

FIG. 9 shows another embodiment of the invention. The program is executed in the direction of larger addresses while updating the addresses. Therefore, program tracing can be easily performed. However, if an address is skipped due to a jump or the like, program trace processing is required. In this embodiment, when an address jumps, the jump destination address is automatically recorded.

Next, the operation of this embodiment will be explained. The program trace device ioo has AB, DB, and R/W.

The STB is connected to the g meter 91 by a signal 150.

The signal 150 is sent after the computer 91 executes the jump process, and when the computer 91 sends the jump destination address on AB, the jump destination address is transferred from AB → gate 800 → bus 810.
The data is recorded in the memory 900 through the process. According to this embodiment, information is automatically written into the memory 900 without the computer 91 performing information writing processing, so that the load on the computer 91 is lightened.

In the figure, 300 is a counter, 400, 450° 500.6
00 is an AND gate, 700,800 is a gate, 310
is a bus, and 410, 510, and 610 are signals.

〔Effect of the invention〕

According to the present invention, program trace processing time is reduced compared to conventional methods.

[Brief explanation of drawings]

1 and 2 are flowcharts of the conventional method, FIG. 3 is a recording area diagram, FIG. 4 is a flowchart of conventional information recording processing, FIG. 5 is a circuit diagram of an embodiment of the present invention, and FIG. 6 ,
Figure 8 is a time chart explaining the operation of Figure 5;
This figure is a memory area diagram, and FIG. 9 is a circuit diagram of another embodiment of the present invention. 9... Computer, 20... Decoder, 30... Counter, 40.50.60... AND gate, 70.
80... No. 1 Kunihaya 2 Ward 5th I No. 6 Pregnancy 7 Kuniyoshi δ Kouhachi λ31 βA ・βHAB, +l

Claims (1)

[Claims] 1. In a program trace device that endlessly records information when important points of a program are passed or interrupt information when an interrupt occurs, there is a memory that records the information, and each time writing or reading to this memory is executed. a counter that specifies one point in the memory endlessly by incrementing by one and returning to the initial value when the final value is reached; a gate that connects the memory and an external data bus; and a gate that detects an address. A program trace device comprising: a decoder for controlling the memory; a circuit for controlling the memory, the counter, and the gate.