Revamp samples and benchmarks

[jrhemstad]

• Created benchmarks/ to hold libcu++ benchmarks
• Moved benchmark.cu/.cpp from samples/ to benchmarks (renamed to concurrency_host/device, but this can be changed)
• Overhauled the old CMakeList.txt for building the benchmarks to use more modern cmake
• Add CMakeList.txt to samples/ to build the existing samples

[jrhemstad]

@griwes I completed everything I planned for this PR. The rtc_example is compiling, but I can't get it to actually run. It fails at runtime with the error:

/usr/include/features.h(367): catastrophic error: cannot open source file "sys/cdefs.h"

1 catastrophic error detected in the compilation of "trie.cu".

I know very little about NVRTC, so I don't know how to resolve this. I suspect it is choking on some dependent include file.

[wmaxey]

@griwes I completed everything I planned for this PR. The rtc_example is compiling, but I can't get it to actually run. It fails at runtime with the error:

/usr/include/features.h(367): catastrophic error: cannot open source file "sys/cdefs.h"

1 catastrophic error detected in the compilation of "trie.cu".

I know very little about NVRTC, so I don't know how to resolve this. I suspect it is choking on some dependent include file.

It looks like NVRTC started looking through system includes. I'm not sure where /usr/include/features would have been included.

[jrhemstad]

@griwes @wmaxey resolved the nvrtc issue. Seemed to be a problem of just using CUDA 10.2. I updated the Cmake to only build the rtc example if the CUDA version is >10.2.

This should be good to go now.

[jrhemstad]

@griwes can you re-review?

[brycelelbach]

Hey Jake, can we rename samples to examples, to match the style in Thrust/CUB?

This also means the top-level README.md in the repo (which is really a symlink to docs/readme.md) will need to update its link.

Also, can you change the extension on the files to .cu? This helps with syntax highlighting, etc.

Also I added the concurrent hash table example.

[jrhemstad]

Also, can you change the extension on the files to .cu? This helps with syntax highlighting, etc.

You want the host only examples to be .cu?

[ogiroux]

I'm good with the nature of these changes. I don't have any additional changes to request.

[jrhemstad]

@brycelelbach I add the concurrent_hash_table.cu to the CMakeLists.txt and renamed samples -> examples.

[griwes]

LGTM.