[Bug tree-optimization/52171] memcmp/strcmp/strncmp can be optimized when the result is tested for [in]equality with 0

[bernds at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=52171
Bug 52171 depends on bug 71413, which changed state.

Bug 71413 Summary: [7 Regression] bootstrap (gnat) broken on arm-linux-gnueabi*
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71413

           What    |Removed                     |Added
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             Status|NEW                         |RESOLVED
         Resolution|---                         |FIXED