X-Git-Url: https://git.stderr.nl/gitweb?a=blobdiff_plain;f=Report%2FMain%2FContext%2FMontiumC.tex;h=e9eb3bfe30383eb3d9b3f5760f882a0377e66675;hb=0ac3f8b7cfb60e71b9f95dc8bf1752e1e971685f;hp=35f1e60c61dbddc7380a8417fb270aae07213ac4;hpb=3f56dcfc5a48f15edc20515946e817e031d2a85a;p=matthijs%2Fprojects%2Finternship.git diff --git a/Report/Main/Context/MontiumC.tex b/Report/Main/Context/MontiumC.tex index 35f1e60..e9eb3bf 100644 --- a/Report/Main/Context/MontiumC.tex +++ b/Report/Main/Context/MontiumC.tex @@ -1,2 +1,51 @@ \section{MontiumC} -This section will describe MontiumC and the montium programming workflow. +\label{MontiumC} +Since having just a piece of hardware is not enough, we also need some way to +program the Montium. To this end, the MontiumC language was created. The +MontiumC language is a language very similar to C. It allows very fine grained +control over the Montium through a set of functions that can be called (where +the function called determines the operation mapped on the Montium). + +MontiumC is, on one hand, a strict subset of C. Every MontiumC program is +therefore a valid C program as well. This is one of the strong points of +MontiumC: By using a normal C compiler, a MontiumC program can be functionally +simulated on normal hardware. + +On the other hand, MontiumC defines a number of special functions which are +mapped onto the Montium ALU when compiling with the Montium-specific +backend. When compiling with a normal C compiler, these functions are +implemented by a library implemented in C. + +Figure \ref{CompilingMontiumC} shows the flow for compiling a MontiumC program +into a Montium binary file, which can be loaded directly onto a Montium. The +process is roughly divided into two parts (each of which corresponds to a +different program in the compiler suite): The frontend and the backend. + +The frontend takes in a MontiumC program and turns it into a lower level +description of the program (the Montium intermediate representation). +The frontend is responsible for mapping higher level C constructs onto +simpler instructions, for canonicalizing and simplifying the code. These +canonicalizations and simplifications ensure that the backend can be +kept simpler and does not have to deal with all the complexities of the +original program. + +The frontend is again divided into two pieces, the first of which +transforms C code into an intermediate representation (called LLVM IR). +For the first part the Clang compiler, part of the LLVM project, is used +mostly unmodified. See section \ref{LLVM} for an overview of the LLVM +project. The second part transforms this intermediate representation +into a simpler form, which is more suitable for mapping onto the Montium +hardware by the backend. The output of this transformation is again in +the the same format, but with a lot of additional constraints. This +extra constrained format is referred to as Montium IR. + +The backend, in turn, takes in this reduced description of the program and +transforms this into a valid Montium binary. To do this, it must find an ALU +configuration to execute a given set of operations, trace values to allocate +them to registers, generate instructions for the adress generation units, etc. + +\begin{figure} +\epsfig{file=Img/Compiling.ps, width=\textwidth} +\caption{MontiumC compilation flow} +\label{CompilingMontiumC} +\end{figure}