On 15/01/14 15:59, Terry Guo wrote: > > >> -----Original Message----- >> From: Richard Earnshaw >> Sent: Wednesday, January 15, 2014 10:30 PM >> To: Terry Guo >> Cc: gcc-patches@gcc.gnu.org >> Subject: Re: [GCC, ARM] Backport trunk fix to 4.8 branch to properly > handle >> rtx of ARM PLD instruction >> >> On 15/01/14 12:37, Terry Guo wrote: >>> >>> >>>> -----Original Message----- >>>> From: Terry Guo [mailto:terry....@arm.com] >>>> Sent: Wednesday, January 15, 2014 8:21 PM >>>> To: Richard Earnshaw >>>> Cc: gcc-patches@gcc.gnu.org >>>> Subject: RE: [GCC, ARM] Backport trunk fix to 4.8 branch to properly >>> handle >>>> rtx of ARM PLD instruction >>>> >>>>> >>>>> Preferably, particularly since you haven't supplied a testcase. >>>>> >>>>> R. >>>> >>>> Bug is reported at http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59826. >>>> I >>> shall >>>> update the patch to include the test case. >>>> >>>> BR, >>>> Terry >>> >>> Here is updated patch along with test case. Is it OK? >>> >> >> I'm rather concerned about the complexity of this patch as a backport. >> Furthermore, part of the problem is that the preload insn is misclassified > as >> an alu_reg operation, which it clearly isn't. >> >> Instead of doing this, please could you try a simpler patch that simply >> reclassifies the "type" of preload as "load1". This would break the >> alu->load/store dependency and thereby avoid the trigger of the problem >> >> R. > > Thanks Richard and you are right. What you said should be the root cause for > this issue. I will implement another patch for trunk to correctly classify > the preload instruction into load1, and then back port to 4.8 branch. > Therefore please consider my request in this thread discarded. >
Trunk has already reclassified it this way. R.
