DAEDAL provides LLVM tools for Decoupled Access Execute. It is currently being developed at Uppsala University.
- Clone this repository to your local machine
- Compile DAEDAL by running make
There are several pre-defined levels of indirection and granularity, as well as compilation target.
- Indirection indicates the maximum numver of indirections that should be considered for data prefetch. All loads with an indirection lower or equal to this number will be turned into prefetches.
- Granularity indicates the number of iterations that should be prefetched and consumed at a time
- Target can be choosen from: DAE, CAE and ORIGINAL, where DAE is Decoupled Access-Execute applied with both indirections and granularities, CAE is coupled Access-Execute applied with only granularities and ORIGINAL is default compiled without any transformations.
Changes of settings can be done under:
$(path to daedal)/sources/common/DAE/Makefile.targets
Variables INDIR_COUNT and GRAN_COUNT can be changed in #line.8 and #line.9 respectively.
Targets can be modified at #line.24.
To illustrate the usage of DAEDAL, we provide one example benchmark which can be found at:
$(path to daedal)/sources/myBenchmark
- In order to build binaries, change $(path to daedal)/sources/common/Makefile.environment to contain the correct path to DAEDAL:
COMPILER_LIB=$(path to daedal)/daedal/compiler/build/projects-build/lib
LLVM_BIN=$(path to daedal)/daedal/compiler/build/llvm-build/bin/
- Run make in $(path to daedal)/sources (parallel make is allowed):
make
The flow of generated output files from TARGET=DAE goes as follows (which can also be observed from Makefile.defaults):
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all .c/.cpp/.cc files get compiled to generate their respective .ll files
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all .ll files are used to generate .stats.ll files which are used for purpose of observations on executable runtime statistics (access/execute times)
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all .stats.ll files are used to mark hot loops for transformation and output .marked.ll files
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all .marked.ll files are used to chunck marked loops and output .gran.ll files
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two global files DAE-header.ll and Globals.ll are genarated (once only). They contain the value that should be used for granulairty. For each granularity DAEDAL will create a copy and replace the granularity with the current one. This copy will then be linked into the final benchmark.
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based on INDIR_COUNT setting, for each indirection Y,
6.1) based on GRAN_COUNT settings, for each granularity X .gran.ll files are used for loop extraction and output .granX**.extract.ll** files
6.1.a) remove redundant prefetches from .granX**.extract.ll** file and output .granX**.indirY.dae.ll** file
6.1.b) Apply pretches on __kernel__ marked functions from .granX**.indirY.dae.ll** file and output .granX**.indirY.dae.O3.ll** file
6.1.c) Global information from DAE-header.ll and Globals.ll are attached together and a new file .granX**.indirY.dae.GV_DAE.ll** is created
6.1.d) with files from 6.1.b) and 6.1.c), an executable file .granX**.indirY.dae** then gets generated
The flow of generated output files for TARGET=CAE is analogous but simpler by skipping steps 6.1.a) and 6.1.b) from above, in step 6.1.d) files are from 6.1) and 6.1.c).
$(path to daedal)/sources/myBenchmark/bin/log.txt
Feel free to try the example benchmark and change/extend to your own applications.
- Copy the myBenchmark directory and replace the sources with your application's source.
- Change the Makefile in your new benchmark directory to use the correct sources, compiler flags, and name:
$(path to daedal)/sources/myBenchmark/src/Makefile
- Change the source Makefile in order to build your benchmark. Add the name of the directory of your benchmark to the list in here:
$(path to daedal)/sources/Makefile
- Mark the loop to transform (using a vectorize pragma). See an example here:
$(path to daedal)/sources/myBenchmark/src/small_benchmark.cpp
- You should be ready to compile your own benchmark now!
More detailed information on DAEDAL can be found in Multiversioned decoupled access-execute: the key to energy-efficient compilation of general-purpose programs. Compiler Construction, March 17-18, 2016: 121-131.
For more information please visit our website.
Please contact us at contact@etascale.com