Basic Integration Usage (<em>CMake</em>)

Code

include/vecscatter.h defined two different code generation targets: a) for use with tiled code b) more importantly, for use with bricked code. The detailed usage are shown with defintions #tile(...) and #brick(...), correspondingly.

For examples see Line 34 in weak/main.cpp using the brick version. One constant expanded version of this call is as follows:

brick("../stencils/mpi7pt.py", "AVX512", (8,8,8), (8), b);

brick

#define brick(...)

Inject stencil code for brick datalayout.

Definition: vecscatter.h:62

Code generation

The code generator, codegen/vecscatter, will run C/C++ preprocessor that can resolve all preprocessor defines and expanded into vecscatter pragma by the preprocessor. The code generator will then scan the processed code and look for #pragma vecscatter to generate the code.

In CMake this code generation step is achieved by simply calling VSTARGET:

VSTARGET(N3MPI main.cpp main-out.cpp)

This defines a code generation target with name N3MPI.

This CMake call uses information defined by include_directories, CMAKE_CXX_FLAGS, and any custom options in ${NAME}_COMPILE_OPTIONS.

The preprocessor to use can be customized by setting variable VS_PREPROCESSOR, who uses cpp as the default.

Compile

The main-out.cpp in the argument to VSTARGET is the code generated output. This is also captured by cmake variable ${VSTARGET_${NAME}_OUTPUT}.

Advanced Integration (<em>Make</em>)

To compile with Make is just as simple. The source code doesn't needs to be changed.

However, the work done with VSTARGET needs to be written as explicit targets in Make.

Vecscatter target

This target calls the code generator by running codegen/vecscatter. The first two arguments are the input and output filename. The other options can be querried by running codegen/vecscatter -h.

main-out.cpp:main.cpp

$(CODEGEN) main.cpp main-out.cpp -- -march=native -O2 -I../include -D../stencils

main-out.cpp can thus be used as normal.