[Bug middle-end/84996] New: Adding or substracting 0.0 could be optimized away even without -ffast-math
antoshkka at gmail dot com
gcc-bugzilla@gcc.gnu.org
Tue Mar 20 16:35:00 GMT 2018
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84996
Bug ID: 84996
Summary: Adding or substracting 0.0 could be optimized away
even without -ffast-math
Product: gcc
Version: 8.0
Status: UNCONFIRMED
Keywords: missed-optimization
Severity: normal
Priority: P3
Component: middle-end
Assignee: unassigned at gcc dot gnu.org
Reporter: antoshkka at gmail dot com
Target Milestone: ---
The code
float test(float lhs) { return lhs + 0.0; }
generates suboptimal assembly
test(float):
addss xmm0, DWORD PTR .LC0[rip]
ret
.LC0:
.long 0
Optimal assembly would be
test(float): # @test(float)
ret
More information about the Gcc-bugs
mailing list