On 18/06/14 10:16, Terry Guo wrote: > > >> -----Original Message----- >> From: Richard Earnshaw >> Sent: Wednesday, June 18, 2014 4:31 PM >> To: Terry Guo >> Cc: gcc-patches@gcc.gnu.org; Ramana Radhakrishnan >> Subject: Re: [Patch, GCC/Thumb-1]Mishandle the label type insn in function >> thumb1_reorg >> >> On 10/06/14 12:42, Terry Guo wrote: >>> Hi There, >>> >>> The thumb1_reorg function use macro INSN_CODE to find expected >> instructions. >>> But the macro INSN_CODE doesn’t work for label type instruction. The >>> INSN_CODE(label_insn) will return the label number. When we have a lot >> of >>> labels and current label_insn is the first insn of basic block, the >>> INSN_CODE(label_insn) could accidentally equal to >> CODE_FOR_cbranchsi4_insn >>> in this case. This leads to ICE due to SET_SRC(label_insn) in subsequent >>> code. In general we should skip all such improper insns. This is the purpose >>> of attached small patch. >>> >>> Some failures in recent gcc regression test on thumb1 target are caused by >>> this reason. So with this patch, all of them passed and no new failures. Is >>> it ok to trunk? >>> >>> BR, >>> Terry >>> >>> 2014-06-10 Terry Guo <terry....@arm.com> >>> >>> * config/arm/arm.c (thumb1_reorg): Move to next basic block if the >> head >>> of current basic block isn’t a proper insn. >>> >> >> I think you should just test that "insn != BB_HEAD (bb)". The loop >> immediately above this deals with the !NON-DEBUG insns, so the logic is >> confusing the way you've written it. >> >> R. >> > > Thanks for comments. The patch is updated and tested. No more ICE. Is this > one OK? > > BR, > Terry >
Yes, this is fine. R. > > thumb1-reorg-v3.txt > > > diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c > index 85d2114..463707e 100644 > --- a/gcc/config/arm/arm.c > +++ b/gcc/config/arm/arm.c > @@ -16946,7 +16946,8 @@ thumb1_reorg (void) > insn = PREV_INSN (insn); > > /* Find the last cbranchsi4_insn in basic block BB. */ > - if (INSN_CODE (insn) != CODE_FOR_cbranchsi4_insn) > + if (insn == BB_HEAD (bb) > + || INSN_CODE (insn) != CODE_FOR_cbranchsi4_insn) > continue; > > /* Get the register with which we are comparing. */ >
