Hi,
Thanks again for your review and useful comments.
>> I see. But I can't really help without a testcase that I can use to have a
>> look
>> (same for the above issue with the segfaults).
The following testcase does not generate "x" as needed.
====================
double t (double x)
{
x = sqrt (x) * sqrt (x);
return x;
}
====================
All of the following operation results in segfault with:-
aarch64-thunder-elf-gcc simlify-2.c -O2 -funsafe-math-optimizations
===============================================
#include <math.h>
double t (double x, double y, double z)
{
x = cbrt (x) * cbrt (y);
x = exp10 (x) * exp10 (y);
x = pow10 (x) * pow10 (y);
x = x / cbrt (x/y)
x = x / exp10 (y);
x = x / pow10 (y);
return x;
}
float t (float x, float y, float z)
{
x = sqrtf (x) * sqrtf (y);
x = expf (x) * expf (y);
x = powf (x, y) * powf (x, z);
x = x / expf (y);
return x;
}
long double t1 (long double x, long double y, long double z)
{
x = sqrtl (x) * sqrtl (y);
x = expl (x) * expl (y);
x = powl (x, y) * powl (x, z);
x = x / expl (y);
return x;
}
===============================================
/* Simplify sqrt(x) * sqrt(y) -> sqrt(x*y). */
(simplify
(mult (SQRT:s @0) (SQRT:s @1))
(SQRT (mult @0 @1)))
/* Simplify pow(x,y) * pow(x,z) -> pow(x,y+z). */
(simplify
(mult (POW:s @0 @1) (POW:s @0 @2))
(POW @0 (plus @1 @2)))
/* Simplify expN(x) * expN(y) -> expN(x+y). */
(simplify
(mult (EXP:s @0) (EXP:s @1))
(EXP (plus @0 @1)))
/* Simplify x / expN(y) into x*expN(-y). */
(simplify
(rdiv @0 (EXP @1))
(mult @0 (EXP (negate @1))))
===============================================
>> A quick "fix" to avoid this ICE would disable the pattern for
>> -ferrno-math.
Disabled the pattern for -ferrno-math.
>> If you open a bugreport with the pattern and a testcase
I'm going to have a closer look.
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67285
Thanks for the detailed explanation of ":s".
Please let me know whether the working patch can be committed?
If its okay and with your approval, I would like to move some more
patterns using "match and simplify".
Thanks,
Naveen
