backend: correctly formulate the exit condition

[liushuyu]

• backend: correctly formulate the exit condition. Previously the exit condition was treated the same as the loop condition (which is the inverse condition of the exit condition). Now, this is corrected.

Should fix #1523

[liushuyu]

The fixed original tree (from #1523) now looks like this:

__attribute__((cdecl))
u64 const_eval_oeis_a006884::test ()
{
  u64 n = 113383;

    u64 RUSTTMP.0;
    u64 n = 113383;
  while (1)
    {
      {
        <D.82>:;
        if (n == 1) break;
        {
                    u64 RUSTTMP.1;
          if ((n & 1) == 0)
            {
              {
                RUSTTMP.1 = n / 2;
              }
            }
          else
            {
              {
                RUSTTMP.1 = n * 3 + 1;
              }
            }
          n = RUSTTMP.1;
        }
      }
    }
  return n;
}

[dkm]

Looks like we don't have many execution test using any loop yet :D

[CohenArthur]

Please add the testcase without const functions to make sure that the exit code is correct. Otherwise, LGTM :) Thanks!

[philberty]

LGTM good catch this was my bad doing too much copy paste

[philberty]

bors r+

[bors]

Build succeeded:

• build-and-check-ubuntu-64bit