JP2626549B2 - Horizontal microprogram optimization method and apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for optimizing a horizontal microprogram, and more particularly to a method for reducing the number of steps of a microprogram by merging some microsteps in a subroutine with the microsteps that call them. The present invention relates to a horizontal microprogram optimizing device capable of reduction.

[0002]

2. Description of the Related Art In general, designers of horizontal microprograms including subroutines regard logically coherent processes as subroutines, and request data required in the subroutines in the subroutines. A subroutine is designed by a combination of several microsteps, and a microprogram is coded to call the subroutine at a necessary place in a main routine. In general, the coded microprogram itself is mounted on the information processing device.

[0003]

The advantage of the horizontal microprogram is that a large number of gates can be controlled in one microstep, so that the number of processing steps is smaller than that of the vertical microprogram. .
That is, one microstep of the horizontal microprogram is divided into a plurality of fields, one field instructs reading of data used in a subsequent microstep, another field instructs transfer between registers, In another field, it is possible to generate a branch address by determining the operation result in the previous microstep. For this reason, microprogram designers
We strive to use as many fields as possible and use as few steps as possible for coding, but in the case of microprograms that include subroutines, we code logically coherent processes as subroutines as described above. Therefore, the above advantages of the horizontal microprogram may not be fully utilized. In other words, in a subroutine considered as a logically coherent process by the designer, there is a microinstruction that can be set in the empty field because there is a space in the field of the calling microstep. This is because in such a case, the number of microsteps of the subroutine can be reduced.

The present invention has been proposed in view of such circumstances, and an object of the present invention is to merge a part of microsteps in a subroutine into a microstep of a calling subroutine so that the steps of the entire microprogram can be performed. It is an object of the present invention to provide a horizontal type microprogram optimizing method and its device capable of reducing the number.

[0005]

In order to achieve the above object, the horizontal microprogram optimizing method of the present invention achieves at least one or more subroutines in a subroutine included in a horizontal microprogram to be optimized. When N microsteps can be merged into the same number of microsteps at all points in the main routine where the subroutine is called, the N microsteps from the head of the subroutine are replaced by the subroutine. Is merged into the same number of microsteps at all points in the main routine, and a subroutine in which the N microsteps are removed from the head of the subroutine is generated and replaced with the original subroutine. The horizontal microprogram optimization of the present invention Subroutine detecting means for detecting a subroutine from a horizontal microprogram to be optimized, and a maximum number of microsteps from the beginning of the subroutine detected by the subroutine detecting means, Merging possibility checking means for checking whether merging is possible into the same number of microsteps at all places where a subroutine is called; and the number of the maximum number of merge steps determined by the merging possibility checking means from the top of the subroutine Merging means for merging the microsteps into the same number of microsteps at all places where the subroutine is called in the main routine, and a subroutine in which the maximum number of microsteps are removed from the head of the subroutine is generated. Said And a subroutine replacement means for replacing the subroutines.

[0006]

In the horizontal microprogram optimizing apparatus according to the present invention, the subroutine detecting means detects a subroutine from the horizontal microprogram to be optimized, and the merging possibility checking means determines whether or not the detected subroutine is included in the detected subroutine. Check if the maximum number of microsteps from the beginning can be merged into the same number of microsteps at all points where the subroutine is called in the main routine, and if the maximum number of merge steps is 1 or more, merge Means for merging the microsteps from the head of the subroutine for the maximum number of merge steps into the same number of microsteps at all points in the main routine where the subroutine is called;
Subroutine replacement means generates a subroutine in which microsteps corresponding to the maximum number of merge steps are removed from the head of the subroutine, and replaces the original subroutine.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described in detail with reference to the drawings.

Referring to FIG. 1, a horizontal microprogram optimizing apparatus 1 according to one embodiment of the present invention inputs a horizontal microprogram to be optimized stored in a storage device 2 such as a floppy disk medium. , A horizontal microprogram in which some of the microsteps in the subroutine included in the substeps are merged with the microsteps of the caller, and output to the storage device 3 such as a floppy disk medium. , A work area 12, a subroutine detecting means 13, a merging possibility checking means 14, a merging means 15, a subroutine replacing means 16, an output means 17, and a command file 18.

The horizontal microprogram to be optimized, which is stored in the storage device 2, is created by coding of a designer, and is mounted on an information processing device either alone or linked to another microprogram. It has an object module format that can be used.

The input means 11 of the horizontal microprogram optimizing device 1 is a means for inputting a horizontal microprogram to be optimized from the storage device 2 and developing it in the work area 12.

[0011] The subroutine detecting means 13 comprises a work area 1
2 is a means for performing processing such as detecting a subroutine from the horizontal microprogram held in the second microprogram 2. An example of the processing is shown in FIG.

The merging possibility checking means 14 merges the maximum number of microsteps from the beginning of the subroutine detected by the subroutine detecting means 13 into the same number of microsteps at all places in the main routine where the subroutine is called. This is a means for checking whether or not it is possible. The merging possibility checking means 14 is capable of physically merging the microsteps from the head of the subroutine into the same number of microsteps of the calling side for each call location in the main routine that calls the same subroutine, and The maximum number of microsteps in which the merged microsteps do not violate the preset restrictions on the use of microinstructions is determined, and the minimum value of the number of microsteps determined for each call location is determined as the maximum number of merge steps. And

The determination as to whether or not a certain micro step of a subroutine can be physically merged with a certain micro step of the calling side is performed as follows.

As described above, each microstep of the horizontal microprogram is composed of a plurality of fields. Now, for convenience of explanation, each microstep is shown in FIG.
As shown in (a), the field is composed of five fields F1 to F5, of which the field F5 is a setting field of a microinstruction indicating the address of the next microstep to be branched, and the remaining four fields F1 to F5. F
For example, it is assumed that a microinstruction or the like for instructing reading or writing of data from the memory is set in No. 4.

In the case of a microprogram having such a configuration, the condition under which a certain microstep of a subroutine can be physically merged with one microstep at a certain place from which the substep is called is determined by each microstep. That is, at least one of the same fields other than the field F5 is an empty field. Here, the microinstruction may be set in both microsteps in the field F5 because the field F5 is a branch microinstruction of the same type except for the next address, and is stored in the field F5 of the merged microstep. This is because it is sufficient to leave one branch microinstruction corresponding to the branch destination.

Therefore, a certain micro step of the subroutine is performed as shown in FIG.
The microinstruction is set only in F5 (the shaded portion indicates that the microinstruction is set), and a certain microstep at the call location is only in fields F2 and F5 as shown in FIG. In the case where a microinstruction is set, the physical instruction can be merged as shown in FIG. On the other hand, as shown in FIG.
If the micro instruction is set to any of
It cannot be physically merged with the microstep of (b).

The determination as to whether or not the merged microstep does not violate a preset restriction on the use of microinstructions is performed as follows.

In general, there are the following types of restrictions on the use of microprograms. Restriction on prohibition of simultaneous operation For example, when an A microinstruction is described in one field, B field is written in another field of the same microstep.
The restriction is that micro instructions must not be described. Restriction on guaranteeing simultaneous operation For example, when a C microinstruction is described in one field, D field is written in another field of the same microstep.
The restriction is that microinstructions must be described. Restrictions on guaranteeing pre-operation For example, when an E microinstruction is described in a certain field of a certain step, an F microinstruction must be described in a certain field of the microstep up to the immediately preceding microstep. The restriction is that it must be done. Restriction on guarantee of post operation For example, if a G microinstruction is described in a certain field of a certain step, and any one of H, I and J microinstructions is described in the same field of a certain subsequent step Is a constraint that a K microinstruction must be described in a certain field of the microstep between them.

Since such a constraint exists for a microprogram, a command for detecting each constraint violation is transmitted, for example, to IF (field F1 = "A") THEN (IF (field F2 = "B") THEN (TRUE) ELSE (restriction violation) with a file stored in the format ELSE (TRUE) for each microstep of the coded microprogram Conventionally, tools that apply all commands in a file and check for constraint violations regarding the use of microprograms have been proposed.

In the horizontal microprogram optimizing apparatus 1 of the present embodiment, the command file held by such a tool is used as it is as a command file 18 and the merged microsteps are stored in the command file 18. All commands are applied to determine if the merge has violated any restrictions on microprogram usage.

It should be noted that the horizontal microprogram stored in the storage device 2 is checked for a constraint violation relating to the use of the microprogram by the tool described above, and if there is no constraint violation, the microstep is merged. Since it is considered that the restrictions that may be violated by the above are limited to the above, the command file 18 in FIG. 1 may store only the command for checking the restriction violation regarding the above.

FIG. 4 shows an example of the processing of the merging possibility checking means 14, and FIG. 5 shows a state where a plurality of commands C1 to Cn are registered in the command file 18.

Next, when the merging possibility checking unit 14 determines that the subroutine detected by the subroutine detecting unit 13 can be merged, the merging unit 15 shown in FIG. This is a means for merging the microsteps from the head of the subroutine for the number of steps into the microsteps for the same number in all places where the subroutine is called in the main routine. This is a means for generating a subroutine in which the micro steps corresponding to the maximum number of merge steps have been removed and replacing the original subroutine, and an example of these processes is shown in FIG. The output unit 17 is a unit that reads out the horizontal microprogram on which the merge processing and the replacement processing have been completed from the work area 12 and outputs the read horizontal microprogram to the storage device 3.

The detailed functions of each part of the horizontal microprogram optimizing apparatus 1 of this embodiment will be described below with reference to the drawings.

The input means 11 of the horizontal type microprogram optimizing device 1 reads out the horizontal type microprogram to be optimized from the storage device 2, expands it in the work area 12, and activates the subroutine detecting means 13.

When activated, the subroutine detecting means 13 starts the processing shown in FIG. First, one subroutine S is searched from the horizontal microprogram stored in the work area 12 (S1). Then, the found subroutine S is notified to the merging possibility checking means 14 (S2), and a notification indicating that there is no merging possibility is issued from the merging possibility checking means 14, or a notice of completion of the replacing process is issued from the subroutine replacing means 16. (S3, S4). If any notification is given, the next subroutine S is searched from the horizontal microprogram in the work area 12 (S5). If found, the process returns to step S2 to repeat the above-mentioned processing. If not found (NO in S6) ),
That is, when the processing for all the subroutines in the horizontal microprogram is completed, the output unit 17 is started (S7), the optimized horizontal microprogram is output to the storage device 3, and the processing is terminated.

Each time the subroutine S is notified from the subroutine detecting means 13, the merging possibility checking means 14
The processing shown in FIG. 4 is executed. First, the subroutine S
Is initialized to 0 (S11), and the horizontal microprogram in the work area 12 is searched sequentially from the top to find one subroutine S calling point (S12). Then, if found (YES in S13), the value of the variable i is incremented by one to "1" (S14), the variable n for managing the number of merge steps is initialized to 1, and the call location found this time is managed as Si ( S15).

First, a total of 2 microsteps of 1 microstep at the head of the subroutine S and 1 microstep at the call location Si are extracted (S1).
6) Then, whether or not the extracted two steps can be physically merged into one step is checked by the above-described method (S1).
7) If physical merging is possible, all the commands C1 to Cn stored in the command file 18 as shown in FIG. A check is made to see if there is a violation (S19). If the restriction on the use of the microinstruction is not violated, the variable n is incremented by 1 to “2” (S21), and the process returns to step S16.

Therefore, next, a total of 4 microsteps of 2 microsteps at the head of the subroutine S, one microstep at the call location Si and one microstep immediately before it are extracted (S16). It is checked by the above-described method whether or not the four microsteps thus obtained can be physically merged into two microsteps (S1).
7). The method of merging here is, for example, the subroutine S
.. Are composed of a first microstep 71, a second microstep 72, a third microstep 73,... As shown in FIG. .., The subroutine S
Is replaced by a micro step 82
And the second micro step 72 is merged with the micro step 81. Then, if the commands can be physically merged, all commands C1 to Cn stored in the command file 18 are further merged into 2
It is applied to all the microsteps to check whether or not the constraint on the use of the microinstruction is violated (S19). If not, the variable n is incremented by +1.
To "3" (S21), and the process returns to step S16.

The above processing is continued until physical merging is not possible or a constraint violation regarding the use of microinstruction is detected, and it is determined in S18 in FIG. Is determined to have violated the constraint on the use of the microinstruction, the variable n
Is 1 (YES in S22), the subroutine S
Are not mergeable at all, the subroutine detecting means 13 is notified of the merge impossibility (S23), and the process is terminated. On the other hand,
If n is not 1, the value of n−1, that is, the maximum number of merge steps at the call location Si is held in the variable ni (S24), and the process returns to step S12.

Returning to step S12, another location calling the subroutine S is searched for, and if found, the same processing as described above is performed on that location. Also, if there is no longer a place where the subroutine S is called (NO in S13), the minimum ni of the maximum number of merge steps for each call place held in each variable ni is replaced with the subroutine S The maximum number of merge steps n _MIN is notified to the merging means 15 together with the variable i, the subroutine S and each Si (S2
5), end the processing. Therefore, for example, if there are five places where the subroutine S is called, and the maximum number of merge steps is 2, 2, 3, 2, 1 respectively, the maximum number of merge steps n _MIN is 1, which means that the merge means 15
Will be notified.

The merging means 15 receives the notification of n _MIN , i, S, Si from the merging possibility checking means 14 every time the
The processing shown in is performed. First, a variable j is initialized to 1 (S31), and n _MIN microsteps from the beginning of the subroutine S are actually merged into n _MIN microsteps of a certain call location Sj determined by the variable j ( S33). Then, the variable j is incremented by 1 (S34), and the same merging is performed for the next call location Sj. When the merging for all the call locations is completed (YES in S32), the subroutine replacing means 16
Start

The subroutine substitution means 16 is activated, the remainder except for the beginning of the n _{MI N-number} of microsteps from a subroutine S as a new subroutine S _MAX (S
35), replacing the subroutine S to the subroutine S _MAX (S36). Then, the end of the replacement process is notified to the subroutine detecting means 13 (S37).

FIG. 8 shows a configuration example of the horizontal microprogram before optimization, and FIG. 9 shows a configuration example of the horizontal microprogram after optimization. In FIG. 8, the subroutine S is composed of five microsteps 101 to 105, and microinstructions f11 and f51 are set in the first and fifth fields of the first microstep 101, respectively. The third and fourth fields are empty fields. Also, second-
In the fifth microstep, the microinstruction is set only in the shaded field. On the other hand, on the main routine side, there are three places where the subroutine S is called, and the first call place, microstep 2
In 01, a microinstruction is set only in the second, third, and fifth fields, and in a microstep 202 immediately before the microinstruction, a microinstruction is set only in the first, second, and fifth fields. Microstep 3, the second call location
01, a microinstruction is set only in the second, third, and fifth fields.
Microinstructions are set in only the? 5 fields.
Microstep 4, the last third call point
In 01, a microinstruction is set only in the second, fourth, and fifth fields. In a microstep 402 immediately before the microinstruction, a microinstruction is set in only the first, second, and fifth fields.

For the horizontal microprogram as shown in FIG. 8, the merging possibility checking means 14 of FIG. 1 sets the maximum number of merge steps n _MIN to “1” for the subroutine S.
Is determined, the merging means 15 merges the microstep 102 at the head of the subroutine S with the microsteps 201, 301, and 401 of the main routine, and merges the microsteps 201 ′, 201 ′ as shown in FIG.
301 ′, 401 ′, and subroutine replacement means 1
6 is the first microstep 10 from the subroutine S
A subroutine S 'as shown in FIG. 9 excluding 1 is generated and replaced with the original subroutine S. This enables a reduction of one microstep.

[0036]

As described above, according to the present invention, a part of microsteps in a subroutine included in a horizontal microprogram is merged with a microstep of its calling source in a main routine. The horizontal microprogram coded by the above can be reduced in the number of steps, the number of steps is smaller, and therefore, the effect of obtaining an optimized horizontal microprogram excellent in performance can be obtained. is there.

Further, the designer does not need to proceed with the coding work while considering whether or not some of the microsteps in the subroutine can be merged with the calling microstep. You can concentrate on coding of micro-programs, and you can work on coding efficiently.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of one embodiment of a horizontal microprogram optimizing device of the present invention.

FIG. 2 is a flowchart illustrating a processing example of a subroutine detecting unit.

FIG. 3 is an explanatory diagram of a method of checking whether or not the merging possibility checking means can physically merge;

FIG. 4 is a flowchart illustrating a processing example of a merging possibility checking unit;

FIG. 5 is a diagram showing an example of the contents of a command file.

FIG. 6 is a flowchart illustrating a processing example of a merging unit and a subroutine replacing unit.

FIG. 7 is an explanatory diagram of a method of merging a plurality of micro steps in a subroutine into the same number of micro steps in a main routine.

FIG. 8 is a diagram illustrating an example of a horizontal microprogram before optimization.

FIG. 9 is a diagram showing an example of a horizontal microprogram after optimization.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Horizontal-type microprogram optimizing device 11 ... Input means 12 ... Work area 13 ... Subroutine detection means 14 ... Merge possibility inspection means 15 ... Merge means 16 ... Subroutine replacement means 17 ... Output means 18 ... Command file 2, 3 ... Storage device

 ──────────────────────────────────────────────────続 き Continued on the front page (56) References IEEE TRANS. ON COM PUTERS, VOL C-20, NO. 7, PP. 783-794, JULY 1971, R.A. L. KLEIR AND C.I. V. RAMAMOORTHY, "OPTIM IZATION STRATEGIES FOR MICROPROGRAM S". IEEE TRANS. ON COM PUTERS, VOL C-23, NO. 8, PP. 791-801, AUGUST 1974, C.I. V. RAMAMOORTHY AND M. TSUCHIYA, "A HIGH-LEVEL LANGUA GE FOR HORIZONTAL MICROPROGRAMMING".

Claims (3)

(57) [Claims] 1. A horizontal microprogram optimizing method for inputting a horizontal microprogram to be optimized and generating an optimized horizontal microprogram, comprising: a horizontal microprogram to be optimized. N micro steps from the beginning of the subroutine included in
If it is possible to merge into the same number of microsteps at all points where the subroutine is called in the main routine, the N
The number of microsteps is merged with the same number of microsteps at all points in the main routine that calls the subroutine, and a subroutine in which the N microsteps are removed from the head of the subroutine is generated. A horizontal microprogram optimizing method characterized by replacing the original subroutine. 2. A horizontal microprogram optimizing device for inputting a horizontal microprogram to be optimized and outputting an optimized horizontal microprogram, comprising: a horizontal microprogram to be optimized. Subroutine detecting means for detecting a subroutine from a subroutine, and the maximum number of microsteps from the beginning of the subroutine detected by the subroutine detecting means can be merged into the same number of microsteps at all points in the main routine where the subroutine is called Means for checking whether the subroutines are the same or not, and the microsteps from the head of the subroutine for the maximum number of merge steps obtained by the merging possibility checking means are all locations in the main routine where the subroutine is called. Microsteps at And a subroutine replacement means for generating a subroutine in which the maximum number of microsteps are removed from the head of the subroutine and replacing the subroutine with the subroutine. Program optimization device. 3. The merging possibility checking means is capable of physically merging the microsteps from the head of the subroutine into the same number of microsteps of the calling side for each call location in the main routine that calls the subroutine. To find the maximum number of microsteps in which the merged microsteps do not violate the preset restrictions on the use of microinstructions, and to determine the minimum value of the obtained number of microsteps as the maximum number of merge steps The horizontal type microprogram optimizing device according to claim 2, characterized in that: