[Bug tree-optimization/81126] New: [6/7/8 Regression] ICE in df_compact_blocks, at df-core.c:1743

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81126

            Bug ID: 81126
           Summary: [6/7/8 Regression] ICE in df_compact_blocks, at
                    df-core.c:1743
           Product: gcc
           Version: 7.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: marxin at gcc dot gnu.org
  Target Milestone: ---

Well, I'm not sure whether it's regression or not, however we ICE on:

$ cat ice.c
void a ()
{
  int c;
  do
    {
      int b;
      if (b)
        b++;
    }
  while (--c);
}

$ gcc -c -O1 -freorder-blocks-and-partition --param iv-max-considered-uses=0 -c
-fprofile-use ice.c

Note: latest trunk does not need -fprofile-use

Started with r228318.