[Bug c/59984] OpenMP and Cilk Plus SIMD pragma makes loop incorrect

[izamyatin at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59984

--- Comment #3 from Igor Zamyatin <izamyatin at gmail dot com> ---
Vectorizer dump snippet for main:

  foo.simdclone.0 (vect__12.7_3, vect_cst_.8_53, vect_cst_.8_53,
vect_cst_.9_51, vect_cst_.9_51);
  GIMPLE_NOP
  vect_v1.12_37 = MEM[(int *)vectp_v1.10_39];   (1)
  v1.0_14 = v1;
  vect_v2.16_60 = MEM[(int *)vectp_v2.14_58];   (2)
  v2.1_15 = v2;
  vect__16.18_63 = vect_cst_.13_7 * vect_cst_.17_62;  <--- constants instead of 
  _16 = v1.0_14 * v2.1_15;                                 vect_v1.12_37 and
  MEM[(int *)vectp_a.19_65] = vect__16.18_63;              vect_v2.16_60 


Then DCE destroys (1) and (2) and later LIM hoists the multiplication away from
the loop.