c++ compilers

[jaespo]

In your experience, which c++ compiler generates the fastest code for 64 bit intel, for a bit-board engine that doesn't use memory management or the std:: library?

I suspect the answer is "it depends", or "it's close", but here are some choices:

1) gcc
2) Microsoft c++
3) clang/llvm
4) Intel c++

[bob]

In your experience, which c++ compiler generates the fastest code for 64 bit intel, for a bit-board engine that doesn't use memory management or the std:: library?

I suspect the answer is "it depends", or "it's close", but here are some choices:

1) gcc
2) Microsoft c++
3) clang/llvm
4) Intel c++

From my testing, Intel is best, but only for actual Intel processors. For AMD there was a bit of trickery going on that made the executable slower, intentionally.

[mar]

I would say intel and gcc are rougly on par but it really depends.
Then clang and last msc, but there are corner cases where a specific compiler can do better than the rest,
but only if you're writing something else than a chess engine.

Intel compiler on AMD:
Intel doesn't use SSE-optimized paths on non-Intel CPUs (the binary can be easily patched though).
I don't know why they still do that because they should have the edge regardless.

For a chess engine this only affects memset and memmove,
so I doubt it will have any noticeable impact unless you copy like crazy.

[jdart]

They are pretty much equal, in my experience. Intel C++ used to be better but current versions of gcc and MSVC are giving it decent competition. Intel still has some good auxiliary profiling and performance tools, though.

--Jon

[velmarin]

Intel is the best,
intrinsic including,
AMD also.

[vittyvirus]

They are pretty much equal, in my experience. Intel C++ used to be better but current versions of gcc and MSVC are giving it decent competition. Intel still has some good auxiliary profiling and performance tools, though.

--Jon

+1
Microsoft VC++ optimizes better than G++ for me.

[SMIRF]

How do you estimate Digital Mars C/C++?