Re: Make FMA code cope with redundant negates (PR89956)

2019-04-04 Thread Jeff Law
On 4/4/19 4:43 AM, Richard Sandiford wrote: > This patch fixes a case in which, due to forced missed optimisations > in earlier passes, we have: > > _1 = a * b > _2 = -_1 > _3 = -_1 > _4 = _2 + _3 > > and treated _4 as two FNMA candidates, once via _2 and once via _3. > > Tested

Make FMA code cope with redundant negates (PR89956)

2019-04-04 Thread Richard Sandiford
This patch fixes a case in which, due to forced missed optimisations in earlier passes, we have: _1 = a * b _2 = -_1 _3 = -_1 _4 = _2 + _3 and treated _4 as two FNMA candidates, once via _2 and once via _3. Tested on aarch64-linux-gnu. OK to install? Richard 2019-04-04 Richa