https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92280
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
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CC| |sergey.shalnov at intel dot com
--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
Sergey, your testcase now fails again. I think there's two changes occuring,
first we now vectorize the store to tmp[] from the first loop during
basic-block vectorization as
_586 = {_148, _142, _145, _139, _54, _58, _56, _60};
_588 = {_211, _217, _214, _220, _292, _298, _295, _301};
MEM <vector(8) unsigned int> [(unsigned int *)&tmp] = _588;
MEM <vector(8) unsigned int> [(unsigned int *)&tmp + 32B] = _586;
then we vectorize the second reduction loop after the fix for PR65930
which then allows us to elide 'tmp' still visible in GIMPLE as
vect__63.9_392 = MEM <vector(4) unsigned int> [(unsigned int *)&tmp];
vect__64.12_388 = MEM <vector(4) unsigned int> [(unsigned int *)&tmp + 16B];
vect__67.19_380 = MEM <vector(4) unsigned int> [(unsigned int *)&tmp + 32B];
vect__68.22_376 = MEM <vector(4) unsigned int> [(unsigned int *)&tmp + 48B];
so assembly has unvectorized first loop and then those latter vectors built
via two times
vmovd %esi, %xmm3
vmovd %esi, %xmm2
vmovd %r11d, %xmm5
vmovd %r15d, %xmm6
vpinsrd $1, %r13d, %xmm2, %xmm4
vpinsrd $1, %r14d, %xmm3, %xmm7
vpinsrd $1, %ebx, %xmm5, %xmm1
vpinsrd $1, %r9d, %xmm6, %xmm0
vpunpcklqdq %xmm1, %xmm0, %xmm8
vpunpcklqdq %xmm4, %xmm7, %xmm9
vinserti128 $0x1, %xmm9, %ymm8, %ymm10
note for the combined fix of PR65930 I see a 7% performance improvement
for 525.x264_r on Haswell.
I think the original complaint in PR83008 was vectorization of the first
loop which still does not happen, so the testcase needs adjustment?
There's also still GIMPLE improvements possible in eliding 'tmp' before
RTL expansion.
