[Bug tree-optimization/66142] Loop is not vectorized because not sufficient support for GOMP_SIMD_LANE

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66142

--- Comment #4 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Ah, and the reason for the ifcvt failure is that we have an unoptimized
virtual PHI in the loop that ifcvt gives up on:
  # .MEM_55 = PHI <.MEM_55(7), .MEM_5(D)(2)>
Only phicprop2 pass is able to optimize that away (and replace all uses
of .MEM_55 with .MEM_5(D)).