| Message ID | 874mw5ns0x.fsf@e105548-lin.cambridge.arm.com |
|---|---|
| State | New |
| Headers | show |
On 09/18/14 04:26, Richard Sandiford wrote: > Patch 4 should make it possible to relax i386'a CANNOT_CHANGE_MODE_CLASS, > solving the missed optimisation that triggered the original thread. > > > gcc/ > * config/i386/i386.c (ix86_cannot_change_mode_class): Remove > GET_MODE_SIZE (to) < GET_MODE_SIZE (from) test. > > Index: gcc/config/i386/i386.c > =================================================================== > --- gcc/config/i386/i386.c 2014-09-15 09:48:11.310438531 +0100 > +++ gcc/config/i386/i386.c 2014-09-15 09:48:11.310438531 +0100 > @@ -37526,13 +37526,6 @@ ix86_cannot_change_mode_class (enum mach > the vec_dupv4hi pattern. */ > if (GET_MODE_SIZE (from) < 4) > return true; > - > - /* Vector registers do not support subreg with nonzero offsets, which > - are otherwise valid for integer registers. Since we can't see > - whether we have a nonzero offset from here, prohibit all > - nonparadoxical subregs changing size. */ > - if (GET_MODE_SIZE (to) < GET_MODE_SIZE (from)) > - return true; > } > > return false; > OK. jeff
Index: gcc/config/i386/i386.c =================================================================== --- gcc/config/i386/i386.c 2014-09-15 09:48:11.310438531 +0100 +++ gcc/config/i386/i386.c 2014-09-15 09:48:11.310438531 +0100 @@ -37526,13 +37526,6 @@ ix86_cannot_change_mode_class (enum mach the vec_dupv4hi pattern. */ if (GET_MODE_SIZE (from) < 4) return true; - - /* Vector registers do not support subreg with nonzero offsets, which - are otherwise valid for integer registers. Since we can't see - whether we have a nonzero offset from here, prohibit all - nonparadoxical subregs changing size. */ - if (GET_MODE_SIZE (to) < GET_MODE_SIZE (from)) - return true; } return false;