Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: cpphackster at gmail dot com
Target Milestone: ---
I have been investigating turning if statements into math operations inspired
by a blog articl
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85466
--- Comment #14 from Daniel Elliott ---
I had a response from chandler carruth on twitter, who informed me that the
benchark was hoisting the computation out of the loop. So thats why clang was
faster. but also he said that the noconditional vers
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85466
--- Comment #15 from Daniel Elliott ---
Good catch johnathan on the return type of max. (PS also enjoyed your accu talk
on youtube).
I also have been messing around with the benchmark a bit and have come to the
conclusion that the sign function
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85466
--- Comment #16 from Daniel Elliott ---
Created attachment 44001
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=44001&action=edit
revised benchmark w/different approach
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85466
--- Comment #17 from Daniel Elliott ---
my previous comment above meant to say this (change from float to int)
Interestingly for the gcc case, if I return float from the when_greater_than
function (which is just doing x > y ? 1: 0; then it
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85466
--- Comment #20 from Daniel Elliott ---
cool. just tried that.
gets gcc down to
GCC:
---
ifStandard 596892 ns
ifNoConditional 148075 ns <--- with "result[n] = tab[item > .
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85466
--- Comment #22 from Daniel Elliott ---
(In reply to Marc Glisse from comment #21)
> (In reply to Daniel Elliott from comment #20)
> > still clang is 1.64x faster. had a look at the assembly. My limited
> > understanding makes me think that the u
