On Tue, 20 May 2014, Richard Earnshaw wrote: > PR 61208 is a wrong code bug in Thumb2 where we can generate out of > range branches due to incorrect instruction size calculations. It's > mostly gone latent on 4.9 and trunk (though could still happen at -O0 > where splitting is done during final instruction generation). > > Complicating things slightly is the fact that prior to 4.9 we had a > single alternative that was emitted statically; we now use an > insn_and_split (hence the reduced impact on 4.9). That means different > patches are needed: one for 4.9 and trunk; another for 4.8 and earlier. > > I've tried to minimize the 4.8 version as much as possible to reduce the > risk. It seems simplest to just provide a new alternative for use with > Thumb2 that has the correct length. Consequently there are two versions > of this patch attached. One for 4.7 and 4.8, the other for 4.9 and trunk. > > PR target/61208 > * arm.md (arm_cmpdi_unsigned): Fix length calculation for Thumb2. > > Testing of the backport version on 4.8 is OK, the trunk version is > ongoing, though I've smoke tested it. > > Richi, is the backport version OK to go into 4.8?
Please wait until after 4.8.3 is released (the bug is not marked as regression and has no known-to-work versions filled in). Richard.
