CoreDSL to TableGen converter / code generator
JavaandMaven
must reside inside $PATH
generate_extension.sh invokes the Java code that does the conversion. It requires both the CoreDSL specification of an extension and the supplementary metadata in a YAML file. The CoreDSL file will typically include other CoreDSL definition files from the RISCV-CoreDSL-Extensions repository therefore it will be easiest to place the CoreDSL file in this directory. The repository has a sample extension s4e-mac.core_desc which together with the accompanying metadata s4e-mac-extension.yaml is used in the following walkthrough.
Sample use:
./generate_extension.sh ../RISCV-CoreDSL-Extensions/s4e-mac.core_desc ../RISCV-CoreDSL-Extensions/s4e-mac-extension.yaml
This generates the index file extensions.yaml and a directory containing code fragments s4emac. If it fails (typically by throwing an exception) then try running with the "-v" switch for clues, check that instructions are described in the metadata, spelled identically, etc.
To add the extension to LLVM a patch file must be created and merged into the source. This requires the accompanying llvm repository which has been ornamented with comments specifying the insertion points for the code fragments, then:
- From the base of the LLVM source tree generate the patch file by passing the index
extensions.yamlthroughinject_extensions.py:
cd ../llvm
../CoreDSL2TableGen/inject_extensions.py ../CoreDSL2TableGen/extensions.yaml > s4e-mac.patch
- Merge the patch:
git am s4e-mac.patch
- Re-build LLVM (the overall extensible-compiler README has further guidance)
To patch LLVM again, for example after modifying the input CoreDSL, it is necessary to remove the existing patch. This can be conveniently done by dropping the commit that merged it, e.g.
git reset --hard HEAD~1
Written in Xtend (Java-derived language for Xtext, used by Eclipse to describe languages), compiles to JAR files for execution. The JAR files are rebuilt by a Maven script:
mvn package
This research is partially funded by the German Federal Ministry of Education and Research (BMBF) within the project Scale4Edge (grant number 16ME0465).