[Bug target/83133] Superflous x86 test instructions in generated assembly.

[glisse at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83133

--- Comment #15 from Marc Glisse <glisse at gcc dot gnu.org> ---
Gcc's RTL internal representation sees the same thing for your code and for

  int diff = (unsigned)a - (unsigned)b;

llvm represents both differently and generates different code for the two.