On 2016-07-20 11:04, Ramana Radhakrishnan wrote: > On Wed, Jul 20, 2016 at 10:56 AM, Aurelien Jarno <aurel...@aurel32.net> wrote: > > On 2016-07-20 10:10, Ramana Radhakrishnan wrote: > >> On Wed, Jul 20, 2016 at 8:48 AM, Aurelien Jarno <aurel...@aurel32.net> > >> wrote: > >> > On ARM soft-float, the float to double conversion doesn't convert a sNaN > >> > to qNaN as the IEEE Std 754 standard mandates: > >> > > >> > "Under default exception handling, any operation signaling an invalid > >> > operation exception and for which a floating-point result is to be > >> > delivered shall deliver a quiet NaN." > >> > > >> > Given the soft float ARM code ignores exceptions and always provides a > >> > result, a float to double conversion of a signaling NaN should return a > >> > quiet NaN. Fix this in extendsfdf2. > >> > > >> > gcc/ChangeLog: > >> > > >> > PR target/59833 > >> > * config/arm/ieee754-df.S (extendsfdf2): Convert sNaN to qNaN. > >> > > >> > gcc/testsuite/ChangeLog: > >> > > >> > * gcc.dg/pr59833.c: New testcase. > >> > >> > >> Ok - assuming this was tested appropriately with no regressions. > > > > Given it only touches arm code, I only tested it on arm and I have seen > > no regression. That said I wouldn't be surprised if the new testcase > > fails on some other architectures. > > I was assuming you tested it on ARM :) In this case given the change > is only in the backend I would have expected this patch to have been > tested for soft-float ARM or an appropriate multilib. Saying what > configuration the patch was tested on is useful for the audit trail. > For e.g. it's no use testing this patch on armhf ( i.e. > --with-float=hard --with-fpu=vfpv3/neon --with-arch=armv7-a) as by > default the test would never generate the call to the library function > but I'm sure you know all that anyway.
Indeed I should have given more details. I tested it on a Debian armel machine, and I configured GCC the same way as the Debian package, that is using --with-arch=armv4t --with-float=soft. I built it once with the new test but without the fix and a second time with both the test and the fix. I have verified that the test fails in the first case and pass in the second case. > I don't know if this would pass or fail on other architectures - if it > fails it indicates a bug in their ports and for them to fix up as > appropriate. > > > > > > Also I have done the copyright assignment for GCC, but I do not have SVN > > write access. Could someone please commit this for me? > > I will take care of it. Thanks again for following up on the patch. Thanks! Aurelien -- Aurelien Jarno GPG: 4096R/1DDD8C9B aurel...@aurel32.net http://www.aurel32.net
