https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64308
Andrew Pinski changed:
What|Removed |Added
Severity|normal |enhancement
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64308
Oleg Endo changed:
What|Removed |Added
CC||olegendo at gcc dot gnu.org
--- Comment #4 f
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64308
--- Comment #3 from Tavian Barnes ---
@Richard Biener: Yes the range for _16 could be [0, 4294967294]. Why can't VRP
can't assume division by zero doesn't occur? If it can then it could say
anything mod [a, b] fits in [0, b - 1].
That's a reas
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64308
--- Comment #2 from Marc Glisse ---
You would need symbolic ranges, b and ret are in [0,m-1]. And then you are
using that very specific x86 instruction that divides 64 bits by 32 bits but
only works if the result fits in 32 bits. It works here be
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64308
--- Comment #1 from Richard Biener ---
Not sure if your analysis is correct, but value-range propagation computes
ret_4: VARYING
...
_12: [0, 4294967295]
_13: [0, 4294967295]
_14: [0, 18446744065119617025]
_15: [0, 4294967295]
_16: [0, +INF]
fo
