From 2e70aee3a563ca6c78c75be1922c9f657a3fc40a Mon Sep 17 00:00:00 2001
From: Yann Herklotz <git@yannherklotz.com>
Date: Wed, 14 Apr 2021 00:03:47 +0100
Subject: Some small fixes

---
 introduction.tex | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

(limited to 'introduction.tex')

diff --git a/introduction.tex b/introduction.tex
index ab13d6c..30ad118 100644
--- a/introduction.tex
+++ b/introduction.tex
@@ -34,7 +34,7 @@ For example, the translation validation for Catapult C~\cite{mentor20_catap_high
 Our position is that none of the above workarounds are necessary if the HLS tool can simply be trusted to work correctly.
 
 \paragraph{Our solution}
-We have designed a new HLS tool in the Coq theorem prover \JW{I think Coq is so standard that it doesn't need a citation (like you don't cite the C programming language, for instance).}~\cite{bertot04_inter_theor_provin_progr_devel} and proved that any output it produces always has the same behaviour as its input. Our tool, called \vericert{},\ifANONYMOUS\footnote{Tool name has been changed for blind review.}\fi{} is automatically extracted to an OCaml program from Coq, which ensures that the object of the proof is the same as the implementation of the tool. \vericert{} is built by extending the \compcert{} verified C compiler~\cite{leroy09_formal_verif_realis_compil} with a new hardware-specific intermediate language and a Verilog back end. It supports all C constructs except for case statements, function pointers, recursive function calls, integers larger than 32 bits, floats, and global variables.
+We have designed a new HLS tool in the Coq theorem prover and proved that any output it produces always has the same behaviour as its input. Our tool, called \vericert{},\ifANONYMOUS\footnote{Tool name has been changed for blind review.}\fi{} is automatically extracted to an OCaml program from Coq, which ensures that the object of the proof is the same as the implementation of the tool. \vericert{} is built by extending the \compcert{} verified C compiler~\cite{leroy09_formal_verif_realis_compil} with a new hardware-specific intermediate language and a Verilog back end. It supports all C constructs except for case statements, function pointers, recursive function calls, integers larger than 32 bits, floats, and global variables.
 
 \paragraph{Contributions and Outline}
 The contributions of this paper are as follows:
@@ -42,10 +42,10 @@ The contributions of this paper are as follows:
 \begin{itemize}
   \item We present \vericert{}, the first mechanically verified HLS tool that compiles C to Verilog. In Section~\ref{sec:design}, we describe the design of \vericert{}.
   \item We state the correctness theorem of \vericert{} with respect to an existing semantics for Verilog due to \citet{loow19_proof_trans_veril_devel_hol}. In Section~\ref{sec:verilog}, we describe how we lightly extended this semantics to make it suitable as an HLS target.
-  \item In Section~\ref{sec:proof}, we describe how we proved the correctness theorem. The proof follows standard \compcert{} techniques -- forward simulations, intermediate specifications, and determinism results -- but we encountered several challenges peculiar to our hardware-oriented setting. \JW{This sentence seems pretty good to me; is it up-to-date with the latest `challenges' you've faced?} These include handling discrepancies between byte- and word-addressable memories, different handling of unsigned comparisons between C and Verilog, and correctly mapping CompCert's memory model onto a finite Verilog array.
-  \item In Section~\ref{sec:evaluation}, we evaluate \vericert{} on the \polybench{} benchmark suite~\cite{polybench}, and compare the performance of our generated hardware against an existing, unverified HLS tool called \legup{}~\cite{canis11_legup}. We show that \JW{Following needs updating with new figures.} \vericert{} generates hardware that is \slowdownOrig$\times$ slower (\slowdownDiv$\times$ slower in the absence of division) and \areaIncr$\times$ larger than that generated by \legup{}. We intend to bridge this performance gap in the future by introducing (and verifying) HLS optimisations of our own, such as scheduling and memory analysis.
+  \item In Section~\ref{sec:proof}, we describe how we proved the correctness theorem. The proof follows standard \compcert{} techniques -- forward simulations, intermediate specifications, and determinism results -- but we encountered several challenges peculiar to our hardware-oriented setting.  These include handling discrepancies between byte- and word-addressable memories, different handling of unsigned comparisons between C and Verilog, correctly mapping CompCert's memory model onto a finite Verilog array and finally correctly rearranging memory reads and writes so that these behave properly as a RAM in hardware.
+  \item In Section~\ref{sec:evaluation}, we evaluate \vericert{} on the \polybench{} benchmark suite~\cite{polybench}, and compare the performance of our generated hardware against an existing, unverified HLS tool called \legup{}~\cite{canis11_legup}. We show that \vericert{} generates hardware that is \slowdownOrig$\times$ slower (\slowdownDiv$\times$ slower in the absence of division) and \areaIncr$\times$ larger than that generated by \legup{}. We intend to bridge this performance gap in the future by introducing (and verifying) HLS optimisations of our own, such as scheduling and memory analysis.
 \end{itemize}
-
+%\JW{This sentence seems pretty good to me; is it up-to-date with the latest `challenges' you've faced?}
 \vericert{} is fully open source and available online.
 
 \begin{center}
-- 
cgit 

