[Bug middle-end/82898] New: Aliasing knowledge is not used to replace memmove with memcpy

[antoshkka at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82898

            Bug ID: 82898
           Summary: Aliasing knowledge is not used to replace memmove with
                    memcpy
           Product: gcc
           Version: 8.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: middle-end
          Assignee: unassigned at gcc dot gnu.org
          Reporter: antoshkka at gmail dot com
  Target Milestone: ---

This has been resolved once in Bug 21602 but now the issue appears again:

void foo(int* i, const float* f) {
    __builtin_memmove(i, f, 1024*1024);
}

Produces assembly:

foo(int*, float const*):
        mov     edx, 1048576
        jmp     memmove   <=== Could be memcpy