On Fri, 25 Jul 2014, Jeff Law wrote: > On 07/24/14 03:35, Richard Biener wrote: > > > > The following fixes one of the most annoying parts of non-working -ftrapv, > > namely that we only support >= word_mode trappings (quite annoying on > > 64bit archs where 'int' is not handled). At least on x86_64 libgcc > > has all the libfuncs available for SImode so the following patch > > arranges for them to be used. RFC because I don't know whether > > they are there by accident... (and thus the patch adds a requirement > > that is not met by other targets - but a link error is better than > > -ftrapv failure?) > > > > The testcase relies on fork() to be able to capture both inline > > and out-of-line trapv sequences. dg-require-fork is unused but > > present, so I use it. I suppose we can restrict the testcase > > to a few targets manually as well - not sure, any preferences? > > > > At least the obvious testcase from PR52478 now works (until > > you hit constant folding ... see PR61893 I just opened). > > > > Bootstrap and regtest running on x86_64-unknown-linux-gnu, ok > > for trunk? > > > > Thanks, > > Richard. > > > > > > 2014-07-24 Richard Biener <rguent...@suse.de> > > > > PR middle-end/52478 > > * optabs.c (gen_int_libfunc): For -ftrapv libfuncs make > > sure to register SImode ones, not only >= word_mode ones. > > * expr.c (expand_expr_real_2): When expanding -ftrapv > > binops do not use OPTAB_LIB_WIDEN. > > > > * gcc.dg/torture/ftrapv-1.c: New testcase. > I'm certainly comfortable requiring more bits in libgcc (which are often going > to be there anyway) to get -ftrapv to work. > > I'd be a little worried the testcase won't work on simulated targets. Perhaps > limit it to native only? I'd consider this is relatively minor issue and not > enough to hold up the patch.
We'd have the simulator effective target to fix that, but I see no runtime related disabling of simulator targets elsewhere so I went ahead and committed the patch without any change. Richard.
