JPH0157375B2 - - Google Patents

Description

[Detailed Description of the Invention] (1) Technical Field of the Invention The present invention relates to an execution control method for a functional machine, particularly in a machine that processes a functional language such as Lisp, in which functions are executed one by one each time a user instructs the machine to execute a function. Steps for evaluating and outputting the situation
In addition to making it possible to easily switch between the mode and the normal mode that is executed continuously,
The present invention relates to an execution control method for functional machines that prevents a decrease in efficiency during normal mode.

(2) Technical background For example, in a computer that processes a functional language such as Lisp used for list processing, an interpreter directly interprets and executes a source program written in a functional language. be done.
Therefore, the user can interactively run and debug programs while talking to the computer. When testing a program, instead of executing the programmed functions one after the other, each function is evaluated one by one each time the user instructs the user to write the name of the function to be evaluated. A function is enabled to notify the user of argument values, return values, detected error information, etc., and to respond to user inquiries regarding the environment, such as the values of global variables.

(3) Prior art and problems FIG. 1 is an explanatory diagram of the operation cycle of a general interpreter, and FIG. 2 is an explanatory diagram of the processing of a conventional step control routine.

As shown in FIG. 1, generally the interpreter 1 is
A function of a program 2 created in a functional language is recursively evaluated and executed. That is, the type of function to be evaluated next is checked in process 3 shown in FIG. 1, the argument is evaluated in process 4, and
After the function is activated or evaluated in process 5, the process returns to process 3 and the process for the next function is repeated in the same way.

A program 2 consisting of a function group consisting of a plurality of functions is normally continuously evaluated and executed by the interpreter 1. However, at the program development stage, if the program is executed continuously, the location of the bug becomes unknown, so it is necessary to check the program while executing it step by step. Therefore, in conventional functional language interpreters,
For example, a dayrail point is provided at point A shown in FIG. 1, and a step control routine 6 as shown in FIG. 2 is inserted at point A, so that the operation of each function can be checked.

That is, after the function type is checked in the process 3 shown in FIG. 1, it is first determined whether the mode is in step mode or not in the step control routine 6 shown in FIG. If it is during debugging, etc., the step mode is displayed in a predetermined storage area. When the step mode is not in effect, control is immediately passed to the illustrated process 4 in FIG. A judgment will be made as to whether Only when the function is defined by the user, a prompt, that is, a message prompting the user to respond, is output to the display or printer, and an instruction from the user is awaited. Examples of instructions from the user include executing the next function and reporting its status, querying the current environment (e.g., the value of a global variable), and changing the execution mode (e.g., canceling step mode). There are things,
When an instruction is received from the user, the instruction is executed, and then control is transferred to process 3 shown in FIG. 1. Therefore, the user can be involved in program execution on a function-by-function basis.

However, according to the above-mentioned conventional system, the interpreter 1 is required to perform the step control routine 6 shown in FIG.
Therefore, even in normal non-step mode, the software always dynamically determines whether or not the current step mode is active. Therefore, there was a problem in that the efficiency in the non-step mode was reduced. In particular, in the case of a high-level language machine using an interpreter, the efficiency of the interpreter itself directly affects the overall performance.

(4) Purpose of the Invention The present invention aims to solve the above-mentioned problems, and without degrading the performance of the interpreter during normal operation.
It is intended to support step mode processing.

(5) Structure of the Invention Therefore, the present invention provides a means for generating a micro-level interrupt only when in the step mode, for example at point A in FIG. The control is then transferred to the step mode processing section. That is, the execution control method of the functional machine of the present invention is as follows.
In a functional machine in which an interpreter interprets and executes a functional language, a control area is provided for the microinstructions executed by the interpreter to indicate whether step exceptions are accepted, and a normal mode is used to continuously process the functional language. Or a mode instruction section that instructs the step mode for interactive processing, and if the control area of the microinstruction is in a state where step exceptions can be accepted when the mode instruction section indicates the step mode, an interrupt is generated. a step control word that interactively determines the level of the step operation to be processed; and a step control word that is activated by the exception detection section and executes the step operation according to the contents of the step control word. It is characterized by having a mode processing section.

Embodiments will be described below with reference to the drawings.

(6) Embodiment of the invention FIG. 3 shows the configuration of an embodiment of the invention. 1 in the diagram
is the interpreter, 10 is the microinstruction execution control unit, 11 is the microinstruction register, 12 is the general exception (EXP) bit, and 3 is the step exception (SEXP).
bit, 14 is a step flag used for mode indication, 15 and 16 are AND gates,
17 is an OR gate, 18 is a sequence control section,
19 is a microprogram counter, 20 is a decoder, 21 is a control storage (CS),
22 represents a step control word, and 23 represents a step mode processing section.

In FIG. 3, an interpreter 1 interprets and executes a functional language using a microprogram based on microinstructions stored in a CS 21. The microinstruction execution control unit 10 is a control unit that sequentially fetches and executes these microinstructions. The microinstructions stored in CS21 are
The microinstruction register 11 is read from an address normally determined by the value of the microprogram counter 19. Each microinstruction has an exception to the general execution sequence.
In addition to the EXP bit 12 which is a control area indicating whether or not to accept a step exception, a field is provided which is a SEXP bit 13 which is a control area indicating whether or not a step exception is accepted. Note that depending on the processing content of the interpreter 1, the EXP bit 12 and the SEXP bit 13 may be used in the same control area. In this embodiment, a case will be explained in which the SEXP bit 13 is provided separately.

The step flag 14 is a mode indicating section that indicates a normal mode for continuous processing of a functional language or a step mode for interactive processing, and is formed of, for example, a flip-flop. In step mode, it is set to "1". The step flag 14 is set or reset by a program or by turning on/off a switch from the operation panel.

The sequence control unit 18 is a logic for controlling the execution sequence of the microprogram, and is configured to determine the next sequence to be executed, and the decoder 20 selects the address thereof.

Step control word 22 indicates the level of step operation to be interactively processed in step mode. It is provided in a specific register or a predetermined location on the main memory. The user can arbitrarily set a desired value before starting the interpreter 1 or while the interpreter 1 is running. Step control word 22
By turning on/off each bit A, B,...C of
For example, whether or not to perform step operations for all functions, whether to perform step operations only for user-defined functions, whether or not to perform step operations only for functions for which trace is specified in the function name atom header, or It is possible to give instructions such as whether or not to perform step operations for all functions. In functional languages, nesting of function calls is often used, and a user-defined function calls many other functions, so the user can use the step control word 22.
By appropriately operating , it is possible to select only the necessary locations to enter the step operation. The step mode processing section 23 executes a step operation according to the contents of the step control word 22.

Next, the control operation of the microinstruction execution control section 10 will be explained.

Among the microinstructions of the interpreter 1, the SEXP bit 13 for the microinstruction corresponding to the position of point A in FIG. 1 is set to be on in advance when the interpreter 1 is created. The user is
When testing a program written in a functional language, the step control word 22 indicates at what level the step operation is to be executed, and the step flag 14 is set. So, when you start the interpreter, interpreter 1
After checking the function type to be evaluated next, the microinstruction whose SEXP bit 13 is on will be loaded into the microinstruction register 13.

The information on SEXP bit 13 is input to AND gate 15 along with the output signal of step flag 14. Both are turned on now, so
The output of AND gate 15 is also turned on, and the OR gate is turned on.
The occurrence of the exceptional condition is transmitted to the sequence control unit 18 via the gate 17. The mechanism in this respect is similar to the mechanism that generates input/output interrupts, and for example, when an exception condition signal such as an input/output interrupt request signal is output,
When the EXP bit 12 is turned on, the output of the AND gate 16 is also turned on, similar to the control in which the occurrence of an exception condition is transmitted via the OR gate 17. The sequence control unit 18 outputs a selection signal for selecting an exception analysis routine address to the decoder 20 instead of selecting the micro program counter 19. Next, the microinstruction for the exception analysis routine is read from the CS 21 to the microinstruction register 11. The exception analysis routine confirms that the step flag 14 is set and starts the step mode processing section 23.

The step mode processing section 23 refers to the step control word 22 and determines the step operation. When a step operation is started, a prompt is output, an instruction from the user is waited for, and the user's instruction is processed interactively.

According to the present invention, the user can set, for example, in the step control word 22 in advance a step operation only for user-defined functions or a step operation only for functions specified to be traced in the function name atom header. When the interpreter 1 reaches the function that you want to trace step by step and prompts you for an instruction by step operation, set new step operation instructions for all functions in the user-defined function in the step control word 22. It is also easy to trace the inside of the function in detail. The step control word 22 may be configured so that the interpreter 1 automatically resets the step operation instruction bit for all functions within the user-defined function when returning from the user-defined function, or when the user no longer needs the step operation. It is also possible to issue a reset instruction when the reset occurs.

When step flag 14 is off, that is, in normal mode, the microinstruction
The output of the AND gate 15 is always "0" regardless of whether the SEXP bit 13 is on or off. Therefore, a program written in a functional language is processed continuously by the interpreter 1 according to the normal execution order.

(7) Effects of the Invention As explained above, according to the present invention, by using a micro-level interrupt mechanism, there is no need for the interpreter to determine by software whether or not to enter a step operation for each function. This prevents the performance of the interpreter from deteriorating, especially in normal mode. Furthermore, in the step mode, the user can freely specify the level of the step operation, allowing efficient debugging and the like. Switching between step mode and normal mode can also be easily performed.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of the operation cycle of a general interpreter, FIG. 2 is an explanatory diagram of the processing of a conventional step control routine, and FIG. 3 is a diagram showing the configuration of an embodiment of the present invention. In the figure, 1 is an interpreter, 10 is a microinstruction execution control unit, 11 is a microinstruction register, and 13
14 is a step exception bit, 14 is a step flag, 18 is a sequence control section, 22 is a step control word, and 23 is a step mode processing section.

Claims (1)

[Claims] 1. In a functional machine where an interpreter interprets and executes a functional language, a control area is provided to indicate whether or not to accept step exceptions in the microinstructions executed by the interpreter, and a normal machine that processes the functional language continuously. mode or a step mode for interactive processing, and a mode instruction section that indicates a step mode to be processed interactively, and a mode instruction section that indicates the step mode and interrupts if the control area of the microinstruction is in a state where step exceptions can be accepted. an exception detection unit that generates an exception, a step control word that interactively determines the level of the step operation to be processed, and a step that is activated by the exception detection unit and executes the step operation according to the contents of the step control word. - An execution control method for a functional machine characterized by having a mode processing section.