Goal:
  
  G : t
  HI : invariants
  HG : acyclic_no_loop
  x : V.t
  p : PathOf x (s G)
  H : VSet.In x (V G)
  lx : Z
  lsx : lsp (s G) x = Some lx
  w : 0 <= lx
  sp := simplify2' p : SPath (V G) x (s G)
  xs : Z
  lxs : lsp x (s G) = Some xs
  wxs : sweight sp <= xs
  ============================
   ((lsp x (s G) + lsp (s G) x <= lsp x x)%nbar -> sweight sp <= 0)


DEBUG:Going to execute:
<coq-core.plugins.ssreflect::ssrrewrite@0> $1 $2
DEBUG LTAC Evaluated term: (simplify2' p)
DEBUG LTAC Evaluated term: (lsp0_spec_le sp)
DEBUG LTAC Evaluated term: le_Some_lsp
DEBUG LTAC Evaluated term: (lsp_codistance x (s G) x)