X-Git-Url: https://svn.cri.ensmp.fr/git/pipstransfo.git/blobdiff_plain/8fa18c3e750daf84d0fa86291e62aa8a4fc63ba8..bd1ddc56ac00510ad44bc3652b86e8ef1ae064e7:/pipstransfo.tex diff --git a/pipstransfo.tex b/pipstransfo.tex index b3186bc..2f4f4ba 100644 --- a/pipstransfo.tex +++ b/pipstransfo.tex @@ -11,19 +11,16 @@ \newcommand\PIPS{PIPS\xspace} - \title{\PIPS~--- List of code transformations} - - \begin{document} - \chapter{Summary} \section{SGuelton} \begin{itemize} + % memory allocation alteration \item scalar renaming % loop transformations @@ -62,12 +59,13 @@ \item split update operator \item statement isolation \item strengh reduction -\end{itemize} +\end{itemize} \section{Teraops} \begin{itemize} + % memory allocation alteration \item scalar renaming \item scalar/array expansion @@ -116,6 +114,7 @@ \item if and loop elimination \item use-def elimination \item constant propagation + \end{itemize} \chapter{List of \PIPS transformations} @@ -124,11 +123,9 @@ \begin{description} -\item[scalar renaming]{is the process of renaming scalar variables to - suppress false data dependencies.} +\item[scalar renaming]{is the process of renaming scalar variables to suppress false data dependencies.} -\item[privatization]{is the process of detecting variables that are - private to a loop body, i.e.\ written first, then read.} +\item[privatization]{is the process of detecting variables that are private to a loop body, i.e.\ written first, then read.} \end{description} @@ -137,32 +134,19 @@ \begin{description} -\item[loop unrolling]{ - is a loop transformation. - Unrolling a loop by a factor of \(n\) consists in the substitution of a loop - body by itself, replicated \(n\) times. A prelude and/or postlude are - added to preserve the number of iteration.} +\item[loop unrolling]{is a loop transformation. +Unrolling a loop by a factor of \(n\) consists in the substitution of a loop body by itself, replicated \(n\) times. +A prelude and/or postlude are added to preserve the number of iteration.} -\item[loop fusion]{ - is a loop transformation that replaces two loops by a single loops whose - body is the concatenation of the bodies of the two initial loops.} +\item[loop fusion]{is a loop transformation that replaces two loops by a single loops whose body is the concatenation of the bodies of the two initial loops.} -\item[loop tiling]{ - is a loop nest transformation that changes the loop execution order - through a partitions of the iteration space into - chunks, so that the iteration is performed over each chunk and in the - chunks.} +\item[loop tiling]{is a loop nest transformation that changes the loop execution order through a partitions of the iteration space into chunks, so that the iteration is performed over each chunk and in the chunks.} -\item[loop interchange]{is a loop transformation that permutes two - loops from a loop nest.} +\item[loop interchange]{is a loop transformation that permutes two loops from a loop nest.} -\item[loop unswitching]{is a loop transformation that replaces a - loop containing a test independent from the loop execution by a test - containing the loop without the test in both true and false branch.} +\item[loop unswitching]{is a loop transformation that replaces a loop containing a test independent from the loop execution by a test containing the loop without the test in both true and false branch.} -\item[loop normalization]{is a loop transformation that changes - the loop initial increment value or the loop range to enforce certain values, - generally~1.} +\item[loop normalization]{is a loop transformation that changes the loop initial increment value or the loop range to enforce certain values, generally~1.} \end{description} @@ -172,114 +156,60 @@ \section{Dead code removal} - - - \begin{description} +\item[inlining]{is a function transformation. +Inlining a function \texttt{foo} in its caller \texttt{bar} consists in the substitution of the calls to \texttt{foo} in \texttt{bar} by the function body after replacement of the formal parameters by their effective parameters.} -\item[inlining]{ - is a function transformation. Inlining a function - \texttt{foo} in its caller \texttt{bar} consists in the substitution - of the calls to \texttt{foo} in \texttt{bar} by the function body - after replacement of the formal parameters by their effective - parameters. -} +\item[forward substitution]{is the process of replacing a reference read in an expression by the latest expression affected to it.} -\item[forward substitution]{ - is the process of replacing a reference read in an - expression by the latest expression affected to it.} +\item[reduction detection]{is an analysis that identifies statements that perform a reduction over a variable.} +\item[parallelism detection]{is a common name for analysis that detect if a loop can be run in parallel.} +\item[parallelism extraction]{is a common name for code transformations that modifies loop nest to make it legal to run them in parallel.} +\item[directive generation]{is a common name for code transformations that annotate the code with directives.} +\item[constant propagation]{is a pass that replaces a variable by its value when this value is known at compile time.} -\item[reduction detection]{ - is an analysis that identifies statements that perform a reduction over a - variable.} +\item[instruction selection]{is the process of mapping parts of the IR to machine instructions.} -\item[parallelism detection]{ - is a common name for analysis that detect if a loop can be run in parallel.} +\item[goto elimination]{is the process of replacing \texttt{goto} instructions by a hierarchical control flow graph.} -\item[parallelism extraction]{ - is a common name for code transformations that modifies loop nest to make it legal to - run them in parallel.} +\item[outlining]{is the process of extracting part of a function body into a new function and replacing it in the initial function by a function call.} -\item[directive generation]{ - is a common name for code transformations that annotate the code with directives.} +\item[common subexpression elimination]{is the process of replacing similar expressions by a variable that holds the result of their evaluation.} -\item[constant propagation]{ - is a pass that replaces a variable by its value when this value is - known at compile time.} +\item[statement isolation]{is the process of replacing all variables referenced in a statement by newly declared variables. +A prologue and an epilogue are added to copy old variable values to new variable, back and forth.} -\item[instruction selection]{ - is the process of mapping parts of the IR to machine instructions.} +\item[dead code elimination]{is the process of pruning from a function all the statements whose results are never used.} -\item[goto elimination]{ - is the process of replacing \texttt{goto} instructions by a hierarchical control flow - graph.} +\item[array linearization]{is the process of converting multidimensional array into unidimensional arrays, possibly with a conversion from array to pointer.} -\item[outlining]{ - is the process of extracting part of a function body into a new function - and replacing it in the initial function by a function call.} +\item[iteration clamping]{is a loop transformation that extends the loop range but guards the loop body with the former range.} -\item[common subexpression elimination]{ - is the process of replacing similar expressions by a variable that holds - the result of their evaluation.} +\item[flatten code]{is the process of pruning a function body from declaration blocks so that all declarations are made at the top level.} +\item[strength reduction]{is the process of replacing an operation by an operation of lower cost.} +\item[split update operator]{is the process of replacing an update operator by its expanded form.} -\item[statement isolation]{is the process of replacing all - variables referenced in a statement by newly declared variables. A - prologue - and an epilogue are added to copy old variable values to new variable, back - and forth.} +\item[n address code generation]{is the process of splitting complex expression in simpler ones that take at most \(n\) operands.} -\item[dead code elimination]{is the process of pruning from a - function all the statements whose results are - never used.} +\item[memory footprint reduction]{is the process of tiling a loop to make sure the iteration over the tile has a memory footprint bounded by a given value.} -\item[array linearization]{is the process of converting - multidimensional array into unidimensional arrays, possibly with a - conversion from array to pointer.} +\item[redundant load-store elimination]{is an inter procedural transformation that optimizes data transfers by delaying and merging them.} +\item[invariant code motion]{is a loop transformation that moves outside of the loop the code from its body that is independent from the iteration.} -\item[iteration clamping]{is a loop transformation that extends - the loop range but guards the loop body with the former range.} +\item[loop rerolling]{finds manually unrolled loop and replace them by their non-unrolled version.} -\item[flatten code]{is the process of pruning a function body from - declaration blocks so that all declarations are made at the top level.} - -\item[strength reduction]{is the process of replacing an operation - by an operation of lower cost.} - -\item[split update operator]{is the process of replacing an update - operator by its expanded form.} - -\item[n address code generation]{is the process of splitting - complex expression in simpler ones that take at most \(n\) operands.} - -\item[memory footprint reduction]{is the process of tiling a loop - to make sure the iteration over the tile has a memory footprint bounded by - a given value.} - -\item[redundant load-store elimination]{is an inter procedural transformation - that optimizes data transfers by delaying and merging them.} - -\item[invariant code motion]{is a loop transformation that moves outside - of the loop - the code from its body that is independent from the iteration.} - - - -\item[loop rerolling]{finds manually unrolled loop and replace - them by their non-unrolled version.} \end{description} - \nocite{*} \bibliographystyle{alpha} \bibliography{refs} - \end{document}