http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46878
--- Comment #20 from Jeffrey A. Law <law at redhat dot com> 2011-01-26 14:56:14 UTC --- -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 01/26/11 07:51, mikpe at it dot uu.se wrote: > http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46878 > > Mikael Pettersson <mikpe at it dot uu.se> changed: > > What |Removed |Added > ---------------------------------------------------------------------------- > CC| |mikpe at it dot uu.se > > --- Comment #19 from Mikael Pettersson <mikpe at it dot uu.se> 2011-01-26 > 14:50:28 UTC --- > (In reply to comment #18) >> Note we're seeing this failure on m68k as well and it's a regression. > > Could it be related to PR46856 (a HAVE_cc0 postreload regression from r162270 > that's breaking m68k-linux)? It's related in the sense that both are problems with cc0 targets, but I doubt the underlying root cause is the same. jeff -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) Comment: Using GnuPG with Fedora - http://enigmail.mozdev.org/ iQEcBAEBAgAGBQJNQDYBAAoJEBRtltQi2kC7r+cH/28xx5O9b7ll8SqYuNMwAIQP vJEStmdjxFEP84DOXd7WPPPyW4qwdEfy2ufFCgorX9MYbyNkxAYGcT96CQUX5jVU z/u+69tzrLwDwcNQ75tLb+THJVwiyUCIz52bNdXo2rHWKGy2yXM+97zdhnBmSNoA Vrr+bLnESl0WiDFxdwlSJALTAEXyRaj4iXR+LR8yN/ewt1bsTt4hIaMmyKcNLuV+ ASOnhFl4x/q+QoURdj9Fd8d2taLVGbKtCeZkPl4nktTp6NvQl4vGBeKgZkHNkZPU RITPyew6a3ISICFNeXlsDjbAnToJQcPoa187AcSlwOLCLdoES53B/qUEZdlZHDc= =uQnW -----END PGP SIGNATURE----- --- Comment #21 from Jeffrey A. Law <law at redhat dot com> 2011-01-26 15:23:15 UTC --- -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 01/25/11 16:42, dj at redhat dot com wrote: > http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46878 > > DJ Delorie <dj at redhat dot com> changed: > > What |Removed |Added > ---------------------------------------------------------------------------- > Attachment #23074|0 |1 > is obsolete| | > > --- Comment #16 from DJ Delorie <dj at redhat dot com> 2011-01-25 23:41:53 > UTC --- > Created attachment 23126 > --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=23126 > alternate patch 3 > > Another patch attempt. In this case, we add a check for the implied > dependency > created by a cc0 setter/user pair to insn_a_feeds_b() so that try_combine() > knows that the cc0 setter is needed if the user is needed. I think you're on the right track here. I want to look at it a bit more, but this might be "it". FWIW, this code was a relatively recent addition to combine to support four insn combinations and just happens to be the code I was concerned might not be cc0-safe. jeff -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) Comment: Using GnuPG with Fedora - http://enigmail.mozdev.org/ iQEcBAEBAgAGBQJNQDxTAAoJEBRtltQi2kC7DqEH/jTegxTzt00RTBmi9pfN77TY 4XdhGv8KZsiFsiEp+IsBdQWhY7xJ12nHwjrBGqz72hDDSoYMflrceIhYqhvPqs3E BzIGmsccr5s+LD/qBQi8bqENOxlADytFia8QpRn22s17v1VhLnk321pFHvS2552G RDASg+ZPnYwrQL9dSKNQ4DKN/W3sTSGe3wLjpSYlhUp4jZ3MjLCMhkLAWaRZ8tWi Q+SfJz5a9bX8sgGCG1Utio0kEhqLYzkgxvgNJoi04059WWuB6uwlsWGcjbd23UTA hjnPRFxpetJp4En7NCOW2eo+2AC97NM909aXwAnvJWUBezDSYZu8fhSbE1rQrjA= =lw6z -----END PGP SIGNATURE----- --- Comment #22 from Jeffrey A. Law <law at redhat dot com> 2011-01-26 16:40:32 UTC --- Patch attempt #3 is OK. Please keep an eye out for complains about cc0 targets not creating loop (dbra) insns. That's my only worry. I don't think it's going to be a problem, but I can't completely rule it out. Thanks for your patience, Jeff
