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-\documentclass[hyperref={pdfpagelabels=false}]{beamer}
-
-%\setbeameroption{show notes}
-
-\mode<presentation>
-{
- %\useinnertheme{echt}
- %\useinnertheme{proef}
- \usetheme{recore}
- \setbeamercovered{transparent}
-%\setbeamertemplate{footline}[frame number]
-}
-
-\usepackage[english]{babel}
-\usepackage[latin1]{inputenc}
-\usepackage{times}
-\usepackage[T1]{fontenc}
-\usepackage{acronym}
-\usepackage{tikz}
-\usepackage{multimedia}
-\usepackage{subfigure}
-\usepackage{booktabs}
-% Can use a tiny fontsize
-\usepackage{fancyvrb}
-
-
-%\usepackage{pgfpages}
-%\pgfpagesuselayout{4 on 1}[a4paper,border shrink=5mm]
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-%For handouts, use the following two lines:
-%\usepackage{pgfpages}
-%\pgfpagesuselayout{2 on 1}[a4paper,border shrink=5mm]
-
-
-\title
-{MontiumC Transforming}
-
-\author {Matthijs Kooijman}
-
-\institute[Recore Systems and University of Twente]
-{
- \inst{}%
- Recore Systems
- \and
- \inst{}%
- Faculty of Electrical Engineering, Mathematics and Computer Science\\
- University of Twente
- }
-
-\begin{document}
-
-\begin{frame}
- \titlepage
-\end{frame}
-
-\begin{frame}{Contents}
- \tableofcontents
-\end{frame}
-
-\section{Introduction}
- \begin{frame}{Montium Tile Processor}
- \begin{itemize}
- \item Explicitely parallel processor
- \item Multilevel reconfiguration
- \item Separate memory addressing units
- \item Data oriented, limited control flow
- \item Redesign on the way
- \end{itemize}
- \end{frame}
-
- \begin{frame}{MontiumC}
- \begin{itemize}
- \item Subset of C
- \item Operations on data using MontiumC API
- \item Compilable by gcc (as C++)
- \item Under constant improvement
- \end{itemize}
- \end{frame}
-
- \begin{frame}{Low Level Virtual Machine (LLVM)}
- \begin{itemize}
- \item Compiler framework.
- \item Provides:
- \begin{itemize}
- \item C Frontend
- \item Intermediate representation (LLVM IR)
- \item Transformation passes
- \item Native codegenerators
- \item JIT compilation
- \end{itemize}
- \item Very modular
- \end{itemize}
- \end{frame}
-
- \begin{frame}{Compiling MontiumC}
- \pgfdeclareimage[width=\textwidth]{Compiling}{images/Compiling}
- \pgfuseimage{Compiling}
- \begin{itemize}
- \item Focus: montiumccfe and transformations
- \end{itemize}
- \end{frame}
-
-\section{Tasks}
-
- \subsection{Original tasks}
- \begin{frame}{Original tasks}
- \begin{itemize}
- \item Select LLVM transformations
- \item Improve and add transformations
- \item Provide debugging information
- \end{itemize}
- \end{frame}
-
- \subsection{Extra tasks}
- \begin{frame}{Extra tasks}
- \begin{itemize}
- \item What is MontiumC?
- \item What is Montium IR?
- \item Reconfigurable binaries
- \end{itemize}
- \end{frame}
-
- \begin{frame}{What is MontiumC?}
- \note{Two angles: What do we want, and what do we support.}
- \begin{itemize}
- \item Status: Specification is ongoing
- \item Challenges:
- \begin{itemize}
- \item Clang is nontransparent
- \note[item]{Clang --- A lot of special cases}
- \item C is complex
- \note[item]{Complex C --- A lot of corner cases}
- \item C is limited
- \note[item]{Limited C --- Need to use annotations, limited amount of types}
- \item Assembly vs. High level
- \note[item]{Tradeoffs -- Code size vs compiler complexity, clarity
- vs control, clarity vs determinism}
- \end{itemize}
- \end{itemize}
- \end{frame}
-
- \begin{frame}[containsverbatim]
- \begin{columns}
- \begin{column}{0.5\textwidth}
- Low level
- \begin{Verbatim}[fontsize=\tiny]
-mem input;
-mem output;
-word factor;
-
-void run(void) {
- factor = from_int(2);
- input = alloc_mem(P0M0);
- output = alloc_mem(P0M1);
- set_base(input, 0);
- set_offset(input, 0);
- set_base(output, -1);
- set_offset(output, -1);
-
- next_cycle();
- word in = read_mem(input);
- word out = p0o0(imul(ra1(in), rc1(factor)))
- add_offset(input, 1);
- add_offset(output, 1);
- init_loop(LC1, 8);
- do {
- write_mem(output, out);
- in = read_mem(input);
- out = p0m0(imul(ra1(in), rc1(factor)))
- add_offset(input, 1);
- add_offset(output, 1);
- } while(loop_next(LC1));
-
- write_mem(output, out);
-\end{Verbatim}
- \end{column}
- \begin{column}{0.5\textwidth}
- High level
- \begin{Verbatim}[fontsize=\tiny]
-P0M0 int input[10];
-P0M1 int output[10];
-
-void run(void) {
- for (int i=0; i<10; ++i)
- output[i] = input[i] * 2;
-}
- \end{Verbatim}
- \end{column}
- \end{columns}
- \end{frame}
- \note{} % Empty filler note page
-
- \begin{frame}{What is Montium IR?}
- \begin{itemize}
- \item Status: Initial version
- \item Challenges:
- \begin{itemize}
- \item Backend is a fast moving target
- \item Corner cases
- \note[item]{Corner case --- global constants}
- \item Hardware dependencies
- \note[item]{Hardware --- Limited number of conditionals possible}
- \end{itemize}
- \end{itemize}
- \end{frame}
-
- \begin{frame}{Selecting LLVM transformations}
- \begin{itemize}
- \item Status: Done
- \item Challenges:
- \begin{itemize}
- \item LLVM Passes assume a lot
- \note[item]{Assumptions --- Immediates are not free}
- \item Montium has specific constraints
- \note[item]{Constraint --- Implicit cycle boundaries and ordering}
- \end{itemize}
- \end{itemize}
- \end{frame}
-
- \begin{frame}{Improving / adding transformations}
- \begin{itemize}
- \item Status: Ongoing
- \item Challenges:
- \begin{itemize}
- \item Staying generic
- \note[item]{Generic --- LLVM maintained passes are a lot easier}
- \item New LLVM features
- \note[item]{Features --- Multiple return values, inlining and
- annotation attributes}
- \end{itemize}
- \end{itemize}
- \end{frame}
-
- \begin{frame}{Debugging information}
- \begin{itemize}
- \item Status: Not started
- \item Challenges:
- \begin{itemize}
- \item Not much LLVM support yet
- \note[item]{LLVM support --- New in clang/backend, no support in
- transformations yet.}
- \item Transformations
- \note[item]{Transformations --- Global arguments, argument addition,
- removal, etc.}
- \end{itemize}
- \end{itemize}
- \end{frame}
-
- \begin{frame}{Reconfigurable binaries}
- \begin{itemize}
- \item Status: Recently started
- \item Challenges:
- \begin{itemize}
- \item Tracking variables
- \note[item]{Tracking --- Through all steps of the process}
- \item Loss of optimizations
- \note[item]{Optimizations --- Hard to encode constraints}
- \item Mostly a backend problem
- \end{itemize}
- \end{itemize}
- \end{frame}
-
-\section{Work process}
- \begin{frame}{Working at Recore}
- \begin{itemize}
- \item Smart people
- \item Fast communication
- \note[item]{Communication --- Mixed teams, easy to "listen in".}
- \item Constructive brainstorming
- \note[item]{Brainstorming --- Evaluating different ideas and approaches.}
- \end{itemize}
- \end{frame}
-
- \begin{frame}{Working with LLVM}
- \begin{itemize}
- \item Large community
- \note[item]{Community --- Companies involved, a lot of full time
- developers.}
- \item Great support
- \note[item]{Support --- mailing list, bug reports solved within 1/2 days.}
- \item Slightly conflicting goals
- \note[item]{Goals --- LLVM aims mainly at "regular" architectures.}
- \end{itemize}
- \end{frame}
-
-\section{Conclusions}
- \begin{frame}{Conclusions}
- \begin{itemize}
- \item LLVM is very suitable
- \item Defining the problem is harder than solving it
- \item Three months is short!
- \end{itemize}
- \end{frame}
-
-\end{document}