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