On Nov 12, 2009, at 10:25 AM, Edward O'Callaghan wrote:> No, its up to them which backend they want to use. > Sounds like they think that GCC is super quick compared to LLVM. Looks > like another fud fart out of google to me.Actually, after chatting with Ian about it, it's more of a case of the FAQ being poorly worded than them being anti-LLVM. If you read it closely, it says that LLVM was too slow for 6g, which is their ultra-fast, non-optimizing implementation based on the Plan9 compilers. In this case, the assertion that LLVM is slow is correct: it's definitely slower than a non-optimizing compiler. They then later implemented an optimizing implementation, which they based on GCC because they had a team member (Ian) who is a GCC expert. On the positive side, Ian seemed very positive and even encouraging that his GCCGo frontend might be retargettable from GCC to LLVM, so I wouldn't rule it out as a possibility if some interested community members stepped up to do it. --Owen -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20091112/556dafb6/attachment.html> -------------- next part -------------- A non-text attachment was scrubbed... Name: smime.p7s Type: application/pkcs7-signature Size: 2620 bytes Desc: not available URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20091112/556dafb6/attachment.bin>
On Thursday 12 November 2009 18:59:51 Owen Anderson wrote:> On Nov 12, 2009, at 10:25 AM, Edward O'Callaghan wrote: > > No, its up to them which backend they want to use. > > Sounds like they think that GCC is super quick compared to LLVM. Looks > > like another fud fart out of google to me. > > Actually, after chatting with Ian about it, it's more of a case of the FAQ > being poorly worded than them being anti-LLVM. > > If you read it closely, it says that LLVM was too slow for 6g, which is > their ultra-fast, non-optimizing implementation based on the Plan9 > compilers.Indeed: "We also considered using LLVM for 6g but we felt it was too large and slow to meet our performance goals." - http://golang.org/doc/go_faq.html#Implementation> In this case, the assertion that LLVM is slow is correct: it's > definitely slower than a non-optimizing compiler.I'm *very* surprised by this and will test it myself... -- Dr Jon Harrop, Flying Frog Consultancy Ltd. http://www.ffconsultancy.com/?e
On Nov 19, 2009, at 10:25 AM, Jon Harrop wrote:> > >> In this case, the assertion that LLVM is slow is correct: it's >> definitely slower than a non-optimizing compiler. > > I'm *very* surprised by this and will test it myself...Compared to a compiler in the same category as PCC, whose pinnacle of optimization is doing register allocation? I'm not surprised at all. --Owen -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20091119/e9914c0b/attachment.html> -------------- next part -------------- A non-text attachment was scrubbed... Name: smime.p7s Type: application/pkcs7-signature Size: 2620 bytes Desc: not available URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20091119/e9914c0b/attachment.bin>