[Bug middle-end/63184] [7/8/9 Regression] Fails to simplify comparison

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63184

--- Comment #20 from Richard Biener <rguenth at gcc dot gnu.org> ---
Created attachment 45179
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=45179&action=edit
patch

This patch fixes the testcases but it comes at a cost without much visible
benefit (trying 258098 expansions in a C,C++ bootstrap with just 4 hits,
all in the same place).