US 5,862,384 A · Compiler optimizer that moves loop invariant expressions

Abstract

A compiler optimizing device provided with an optimizing section comprising an update variable control table to control the update variables to be changed in relation to the functions contained in the loop invariant expression, an update variable extraction section to extract the update variables for each function contained in the loop invariant expression for registration to the update variable control table, an update variable review section to register the variables which are, when a certain function in the loop invariant expression calls another function, updated by the called function to the update variable control table as the update variables of the calling function, and a reference loop invariant expression transfer section to transfer the loop invariant expressions out of the loop based on the update variables recognized in access with the update variable control table.

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Claims12

Dependent claims

A compiler optimizing device having a lexical analysis means to decompose a source program into lexical units, a syntactic analysis means for syntactic analysis upon receipt of lexical analysis result, an optimizing means to optimize a code by transferring loop invariant expressions, and a code generation means to generate an object code upon receipt of optimization result,

said optimizing means further comprising:
an update variable control means for controlling update variables to be changed in relation to functions contained in said loop invariant expression;
an update variable extraction means for extracting the updated variables of each function contained in said loop invariant expression and registering them to said update variable control means;
an update variable review means for registering variables updated by called function when a certain function in loop invariant calls another function to said update variable control means as the update variables of calling function;
a reference loop invariant expression transfer means for extracting the loop invariant expressions based on the update variables it recognized by accessing said update variable control means and transfers them out of the loop.

2 more elements

A compiler optimization method comprising the steps of:

a lexical analysis step for to decomposing the source program into lexical units;
a syntactic analysis step for syntactic analysis upon receipt of the lexical analysis result;
an optimizing step for optimizing the code by transferring the loop invariant expressions and a code generation means to generate the object code upon receipt of the optimization result;
wherein said optimizing step further comprising:
a first step for extracting the update variables of each function contained in the loop invariant expression to register to an update change control means for controlling the update variables to be changed in relation to the functions contained in the loop invariant expressions;
a second step to register the variables updated by the called function when a certain function in the loop invariant expression calls another function to said update variable control means as the update variables of the calling function;
and
a third step to extract the loop invariant expression based on the update variables recognized in access to said update variable control means and to transfer them out of the loop.

5 more elements

Dependencies are inferred from the claim text.

Description16,656 words

Summary5,384 words

#1. Field of the Invention

#The present invention relates to an optimizing device for code optimization in the compiler and particularly relates to a compiler optimizing device which makes optimization by transfer of the loop invariant expressions and the method therefor.

#2. Description of the Related Art

Brief description of the drawings32 figures

#The present invention will be understood more fully from the detailed description given herebelow and from the accompanying drawings of the preferred embodiment of the invention, which, however, should not be taken to be limitative to the invention, but are for explanation and understanding only.

#In the drawings:

#FIG. 1 is a block diagram to show the configuration of a compiler optimizing device according to an embodiment of the present invention;

Detailed description10,386 words

#The preferred embodiment of the present invention will be discussed hereinafter in detail with reference to the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. It will be obvious, however, to those skilled in the art that the present invention may be practiced without these specific details. In other instance, well-known structures are not shown in detail in order to unnecessary obscure the present invention.

#FIG. 1 is a block diagram to show the configuration of a compiler optimizing device according to an embodiment of the present invention. As shown in the figure, an optimizing device of this embodiment comprises a lexical analysis section 10 which decomposes the source program into lexical units, a syntactic analysis section 20 which, upon receipt of the lexical analysis result, makes syntactic analysis, an optimizing section 30 which optimizes the code by transferring the loop invariant expressions, and a code generation section 70 which, upon receipt of the optimization result, generates the object code.

#The optimizing section 30 is, as shown in the figure, provided with an update variable extraction section 40, an update variable review section 50, a reference loop invariant expression transfer section 60 and an update variable control table 300.

Facts

Application

08/783,061Filed 15 Jan 1997

Priority

JP 8-00590817 Jan 1996

Granted

19 Jan 1999

Term ended

15 Jan 2017

Estimated · how

20 years from earliest known nonprovisional domestic filing. Maintenance-fee lapses, terminal disclaimers and statutory extensions have not been checked. The continuity chain may be incomplete; this is not an enforceability determination. Patent term adjustment is unavailable; no adjustment was added.

Classification2 codes

G06F 8/443
Encoding: optimisation
G06F
Computing and data processing

Description16,656 words

Summary5,384 words

#1. Field of the Invention

#2. Description of the Related Art

Brief description of the drawings32 figures

#In the drawings:

#FIG. 1 is a block diagram to show the configuration of a compiler optimizing device according to an embodiment of the present invention;

Detailed description10,386 words

Compiler optimizer that moves loop invariant expressions

Life of this patent

Compiler optimizer that moves loop invariant expressions

Life of this patent

Life of this patent

Abstract

Drawings

Drawings

Claims12

Description16,656 words

Drawings

Classification2 codes

Life of this patent

Description16,656 words