[Bug tree-optimization/77644] missed optimization with sqrt in comparison

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77644

--- Comment #5 from Richard Biener  ---
Err, abs(A) < sqrt (B) isn't handled yet, no?  Though I'm not sure if it's wise
to emit A * A < B for that given A * A is going to drop of quite some bits in
precision and likeliness to overflow / underflow to +Inf / denormal is high.

[Bug tree-optimization/77644] missed optimization with sqrt in comparison

[prathamesh3492 at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77644

prathamesh3492 at gcc dot gnu.org changed:

   What|Removed |Added

 CC||prathamesh3492 at gcc dot 
gnu.org

--- Comment #4 from prathamesh3492 at gcc dot gnu.org ---
Fixed on trunk.

[Bug tree-optimization/77644] missed optimization with sqrt in comparison

[prathamesh3492 at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77644

--- Comment #3 from prathamesh3492 at gcc dot gnu.org ---
Author: prathamesh3492
Date: Wed May 10 13:26:09 2017
New Revision: 247835

URL: https://gcc.gnu.org/viewcvs?rev=247835=gcc=rev
Log:
2017-05-10  Prathamesh Kulkarni  

PR tree-optimization/77644
* match.pd (sqrt(x) cmp sqrt(y) -> x cmp y): New pattern.

testsuite/
* gcc.dg/tree-ssa/pr77644.c: New test-case.

Added:
trunk/gcc/testsuite/gcc.dg/tree-ssa/pr77644.c
Modified:
trunk/gcc/ChangeLog
trunk/gcc/match.pd
trunk/gcc/testsuite/ChangeLog

[Bug tree-optimization/77644] missed optimization with sqrt in comparison

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77644

--- Comment #2 from Richard Biener  ---
Well, even generally sqrt (X) CMP sqrt (Y) -> X CMP Y at least if there are no
NaNs and with -funsafe-math-optimization (because rounding effects could make
sqrt (X) == sqrt (Y) when X != Y).

[Bug tree-optimization/77644] missed optimization with sqrt in comparison

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77644

Andrew Pinski  changed:

   What|Removed |Added

   Keywords||easyhack
 Status|UNCONFIRMED |NEW
   Last reconfirmed||2016-09-21
 Ever confirmed|0   |1

--- Comment #1 from Andrew Pinski  ---
Confirmed, This shouldn't be a hard project just starting out and they can
modify match.pd to do it.

[Bug tree-optimization/77644] missed optimization with sqrt in comparison

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77644

Andrew Pinski  changed:

   What|Removed |Added

   Keywords||missed-optimization
   Severity|normal  |enhancement