Am 27.10.2018 um 18:21 schrieb Ben Grasset: > On Sat, Oct 27, 2018 at 8:47 AM Jonas Maebe <jo...@freepascal.org > <mailto:jo...@freepascal.org>> wrote: > > On 27/10/18 05:45, Ben Grasset wrote: > > > > You also need "opt" if you want to perform full optimizations (or just > use clang, which a.o. combines the functionality of llc and opt). > > There's one more problem I forgot to mention in my first post, and it is > probably a deal breaker for the original bounty: LLVM does not support > Borland's fastcall calling convention for i386. So you would need to add > support for Borland fastcall on i386 to LLVM if it has to support > existing i386 inline assembly routines written for FPC/Delphi. > > Finally, adding support for 32 bit targets in FPC's LLVM backend would > also require some work due to how FPC's code generator is structured, > and due to the fact that need to have two code generators in a single > binary (the native one to support the generation of entry and exit code > for pure inline assembler routines, and the LLVM one for the rest). > > > LLC (at least now) statically links the necessary parts of LLVM and works > independently of Opt, with a simpler set of > command line options (it just has overall O1, O2, and O3 flags.) > > As far as the point about assembly on 32 bit, while it does seem like that > would be a problem for the bounty > requirements, would it really be the end of the world in a more general > sense? I can't imagine people who are still > using 32-bit-hardware and writing 32-bit applications would complain if the > LLVM backend was not available for 32-bit. > > Anyways though, I do think code gen improvements for FPC, LLVM or not, are > likely going to be a lot more widely helpful > than just rewriting exception handling....
If you read the whole thread, LLVM needs a rewritten exception handling as well. Further, a quick test of table based exception handling on bansi1 (which is mainly a memory manager test) gives: standard exception handling: fpctrunk\tests\bench>pp11 bansi1 -O3 fpctrunk\tests\bench>bansi1 Test 1: 1000000 done in 0.537 sec Test 2: 1000000 done in 0.535 sec Test 3: 1000000 done in 0.587 sec SEH based exception handling: fpctrunk\tests\bench>pp11 bansi1 -O3 fpctrunk\tests\bench>bansi1 Test 1: 1000000 done in 0.456 sec Test 2: 1000000 done in 0.457 sec Test 3: 1000000 done in 0.446 sec _______________________________________________ fpc-devel maillist - fpc-devel@lists.freepascal.org http://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-devel
