3 ms·
Assuming the FORTRAN77 was optimized for hardware circa a period when FORTRAN77 wasn't considered an ancient language, is it still optimized on modern hardware?
by cbd1984 12y ago
Assuming the FORTRAN77 was optimized for hardware circa a period when FORTRAN77 wasn't considered an ancient language, is it still optimized on modern hardware? Because it seems the vast increase in the relative importance of cache alone, not to mention the great changes in cache sizes, would make some optimizations fairly pessimal these days. (For example, loop unrolling blowing out I-cache.)
- colechristensen 12y agoLanguages aren't optimized, compilers are, and fortran compilers commercial and free are released regularly.
- cbd1984 12y ago> Languages aren't optimized, compilers are Actually, specific pieces of code get optimized, and compilers that can "undo" optimizations put in to the source code by hand are so rare I daresay they don't exist.
- brorfred 12y agoThe intel compiler is considered to generate runtimes that runs about twice as fast as runtimes from gfortran. Haven't seen any recent tests of CLANG/LLVM yet. The statement that compilers, not languages, are optimized generally holds true for Fortran.
- gnufx 12y ago"Considered" maybe, but not measured in practice. Of course you need equivalent optimizations to generate similar code -- Intel even defaults to incorrect optimizations. GCC is also substantially more reliable in my experience watching users who insist on using Intel on HPC systems without actually measuring anything. Of course compilers are relevant, but Fortran has long presented optimization possibilities that aren't typically available in other languages, like not passing by reference.