79 lines
2.1 KiB
Text
79 lines
2.1 KiB
Text
.TL
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The design and implementation of
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the EM Global Optimizer
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.AU
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H.E. Bal
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.AI
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Vrije Universiteit
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Wiskundig Seminarium, Amsterdam
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.AB
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The EM Global Optimizer is part of the Amsterdam Compiler Kit,
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a toolkit for making retargetable compilers.
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It optimizes the intermediate code common to all compilers of
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the toolkit (EM),
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so it can be used for all programming languages and
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all processors supported by the kit.
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.PP
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The optimizer is based on well-understood concepts like
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control flow analysis and data flow analysis.
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It performs the following optimizations:
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Inline Substitution, Strength Reduction, Common Subexpression Elimination,
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Stack Pollution, Cross Jumping, Branch Optimization, Copy Propagation,
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Constant Propagation, Dead Code Elimination and Register Allocation.
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.PP
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This report describes the design of the optimizer and several
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of its implementation issues.
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.AE
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.bp
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.NH 1
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Introduction
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.PP
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.FS
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This work was supported by the
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Stichting Technische Wetenschappen (STW)
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under grant VWI00.0001.
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.FE
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The EM Global Optimizer is part of a software toolkit
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for making production-quality retargetable compilers.
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This toolkit,
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called the Amsterdam Compiler Kit
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.[
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tanenbaum toolkit rapport
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.]
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.[
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tanenbaum toolkit cacm
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.]
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runs under the Unix*
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.FS
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*Unix is a Trademark of Bell Laboratories
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.FE
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operating system.
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.sp 0
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The main design philosophy of the toolkit is to use
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a language- and machine-independent
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intermediate code, called EM.
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.[
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keizer architecture
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.]
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The basic compilation process can be split up into
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two parts.
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A language-specific front end translates the source program into EM.
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A machine-specific back end transforms EM to assembly code
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of the target machine.
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.PP
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The global optimizer is an optional phase of the
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compilation process, and can be used to obtain
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machine code of a higher quality.
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The optimizer transforms EM-code to better EM-code,
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so it comes between the front end and the back end.
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It can be used with any combination of languages
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and machines, as far as they are supported by
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the compiler kit.
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.PP
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This report describes the design of the
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global optimizer and several of its
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implementation issues.
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Measurements can be found in.
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.[
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bal tanenbaum global
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.]
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