On Sun, Aug 2, 2020 at 12:02 PM Roger Sayle <ro...@nextmovesoftware.com> wrote: > > > The following patch avoids simplifying x-0.0 to x when -fsignaling-nans is > specified, > which resolves PR rtl-optimization 61494. Indeed, running the test program > attached > to that PR now reports no failures. Alas reducing that validation program > to a portable > test for the GCC testsuite is a challenge that I plan to leave to a > volunteer. The fix > itself is a trivial one-liner, so it's curious that the compiler has been > broken for so long. > Hopefully folks agree that correctness is more important than testability > (but both > are desirable). > > The following patch has been tested on x86_64-pc-linux-gnu with a "make > bootstrap" > and "make -k check" with no new regressions. > Ok for mainline?
Heh, and I thought we do no FP math simplifications on RTL ... OK. Thanks, Richard. > 2020-08-02 Roger Sayle <ro...@nextmovesoftware.com> > > gcc/ChangeLog > PR rtl-optimization/61494 > * simplify-rtx.c (simplify_binary_operation_1) [MINUS]: Don't > simplify x - 0.0 with -fsignaling-nans. > > Thanks in advance, > Roger > -- > Roger Sayle > NextMove Software > Cambridge, UK >
