[Bug testsuite/86540] [9 Regression] pr77445-2.c and ssa-dom-thread-7.c regressions since May 20, 2018

[law at redhat dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86540

Jeffrey A. Law <law at redhat dot com> changed:

           What    |Removed                     |Added
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          Component|middle-end                  |testsuite

--- Comment #4 from Jeffrey A. Law <law at redhat dot com> ---
These are both caused by the increased CASE_VALUES_THRESHOLD for aarch64.  That
changes decisions in the switch conversion code which in turn expose new
(unexpected) jump threading opportunities after switch conversion.

I checked all the other targets that have a non-default CASE_VALUES_THRESHOLD. 
Only aarch64 is high enough to trigger these issues.  So I'm just going skip
those tests on aarch64.  If we find ourselves adding more twiddles to that list
over time we'll probably want a better way to control, either at the compiler
level or in testing harness.

I'll fix this momentarily on the trunk.