JP3085309B2 - Debug system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Overview] Regarding a debug system for debugging a variable assigned to a register / area, a register / area assigned to a variable and an entity of the variable is generated and stored as debug information in advance, and debugging is performed. The purpose is to change the value of the corresponding register / area by referring to this at the point of interruption sometimes, so that the user can perform correct debugging without being conscious of the actual location of the variable by optimization. The information of the registers / areas fixedly assigned to the variables by optimization and the registers / areas assigned to the entity of the variables only at a specific time is generated and stored as debug information in advance, and the instruction sequence in which the source program is expanded during debugging is stored. At the interrupted position, refer to the debug information above to access the register / area assigned to the variable and the entity of the variable. And configure it for debugging.

[Industrial applications]

The present invention relates to a debug system for debugging variables assigned to registers / areas.

[Problems to be solved by conventional technology and invention]

Conventionally, when debugging a variable that allocates registers in addition to an area only at a specific time due to optimization, since only fixed areas or registers were conscious,
There is a problem that variables cannot be debugged correctly for variables to which registers are assigned locally. For example, as shown in FIG. 4, when the execution of the program is interrupted at the position of the arrow in statement 3 and the value of the variable A is to be changed by the function of the debugger, the area allocated to the variable A Even if the value of only A is changed, at this time, the result of the variable A is temporarily allocated by optimization to the register reg1 as shown in the figure, so that the result cannot be reflected in the statement result. There was a problem that debugging was not possible.

According to the present invention, a register / region allocated to a variable and an entity of the variable is generated and stored in advance as debug information, and the value of the register / region is changed by referring to the register / region at a break point during debugging. The purpose is to enable users to perform correct debugging without being conscious of the actual location of variables through optimization.

[Means to solve the problem]

 FIG. 1 shows a principle configuration diagram of the present invention.

In FIG. 1, a source program 1 is a program before development to be debugged.

The expanded instruction sequence 2 is an instruction sequence obtained by expanding the source program 1 and is a machine language program to be debugged.

The debug information 3 is information in which registers / areas fixedly allocated to variables by optimization and registers / areas allocated to the substance of variables only at a specific time are generated and stored in advance. Here, only the registers allocated to the entity of the variable only at a specific time (for example, the time from statement 2 to statement 3) are shown.

[Action]

According to the present invention, as shown in FIG.
Is stored, and at the interrupted position of the instruction sequence 2 in which the source program 1 has been expanded at the time of debugging, the debug information 3 is referenced to find a register / region allocated to the variable and the entity of the variable, and access these. I'm trying to debug.

Therefore, when trying to change the value of a variable by interrupting the execution of a program using a debugger, the value of the corresponding register / area is changed by referring to the stored debug information 3. Thus, correct debugging can be performed without the user being aware of the actual location of the variable due to optimization.

Embodiment Next, the configuration and operation of an embodiment of the present invention will be sequentially described in detail with reference to FIG. 1 to FIG.

In FIG. 1, a source program 1 is a program before development to be debugged, and a statement 1 (A =
1), sentence 2 (B = 2), and sentence 3 (C = A + B).

The expanded instruction sequence 2 is an instruction sequence obtained by expanding the source program 1.
This is a machine language instruction sequence obtained by expanding sentence 3 as illustrated. For example, statement 1 (a source program that assigns A = 1, 1 to variable A) is loaded as LOAD reg1,1 (1) STORE reg1, A・ ・ ・ ・ ・ ・ ・ ・ ・ (2) Here, (1) is an instruction sequence for loading 1 into the register reg1, and (2) is an instruction sequence for storing the contents of the register reg1 in the area allocated to the variable A. Hereinafter, sentences 2 and 3 are similarly expanded.

The debug information 3 is information in which registers / areas fixedly assigned to variables by optimization at the time of translation and registers / areas assigned to entities of variables only at specific times are generated and stored in advance. Here, as shown in the figure, information that A has been assigned to reg1 for sentences 2 to 3 and information (not shown) that A and B have been respectively assigned to areas are generated and stored. Therefore, statement 3
When trying to change the value of the variable A when interrupted at the position indicated by the arrow with
Register in which the contents of the area and the substance of the variable A exist
By changing both of the contents of g1, you can debug correctly.

 FIG. 2 shows an example of debug information according to the present invention.

FIG. 2A shows a source program 1 and an expanded instruction sequence 2 of the source program 1.

 FIG. 2B shows the debug information 3.

The data information includes variable names, variable attributes, register / area allocation information, and the like corresponding to the statements 1, 2, and 3 in FIG.

The statement information includes, in the order of statement 1, statement 2, statement 3 in FIG. 2 (a), the line number on the source program 1, the offset address of the expanded instruction string 2, and the like.

The register allocation information has information indicating that the allocation destination of the variable is locally changed. Here, "A is the register reg1
2 to 3 ”means that the substance of variable A is stored in register reg1 in statement 2.
It is the information that is assigned from to.
The fixed assignment of the variable A to the area is held by data information.

Next, in the order shown in the flowchart of FIG.
The operation of the configuration of the embodiment of the present invention will be specifically described with reference to the drawings.

In FIG. 3, it is checked which sentence is currently interrupted from the sentence information. For example, in the case where the program is interrupted at the position described as “interrupted” in FIG. 2 (a), it is determined from the information of the statement in the debug information 3 that the program is interrupted at the beginning of the sentence (specifically, FIG. 2 (b)). Specifically, a sentence including the offset address of the interruption point is found as sentence 3).

Checks whether the substance of the variable is in the register from the register allocation information. For example, referring to the register allocation information in FIG. 2 (b), it is checked whether variables A and B are allocated to the registers. As a result, it is found that the variable A is allocated to the register reg1 by the statement 3 which is currently suspended. Prove. Therefore, since it is determined that the variable A is assigned to the register, the contents of the register (register reg1) are changed and the contents of the area are changed. on the other hand,
Since it has been determined that the variable B has not been allocated to the register, only the contents of the area are changed.

As described above, when it is determined that the substance of the variable is temporarily allocated to the register by referring to the debug information 3 at the break point at the time of debugging, the contents of the determined register and the fixed allocation are performed. By changing both of the areas, it is possible to correctly change the contents of the variables and debug.

〔The invention's effect〕

As described above, according to the present invention, when the execution of a program is interrupted using a debugger and the value of a variable is to be changed, the stored debug information 3 is referred to and fixed to the variable. The user is conscious of the location of the variable entity by optimization because it employs a configuration that accesses both the register / area temporarily allocated and the register / area temporarily allocated to the entity of the variable. Not
Correct debugging can be easily performed.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the principle of the present invention, FIG. 2 is an example of debug information according to the present invention, FIG. 3 is a flowchart for explaining the operation of the present invention, and FIG. In the figure, 1 is a source program, 2 is an expanded instruction sequence,
3 represents debug information.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G06F 11 / 28,9 / 44

Claims (1)

(57) [Claims] 1. A debugging system for debugging a program, comprising: storage means for storing debug information including register allocation information indicating to which register each variable is allocated to which register in the program; Detecting means for detecting at which position the interrupt is interrupted; and when changing the contents of the variable area by debugging, when it is determined that the variable register is allocated to the variable register at the interrupted position based on the register allocation information, Debugging means for changing the contents of the variable area together with the contents of the register.