[Bug target/81763] Issues with BMI on 32bit x86 apps on GCC 7.1+

[mike at fireburn dot co.uk]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81763

--- Comment #6 from Mike Lothian <mike at fireburn dot co.uk> ---
I tried the test case with

gcc -O2 -march=native test.c -o test

and 

gcc -O2 -march=native -mno-bmi test.c -o test

Both executables seem to run with no output

I've only seen the issue in radeonsi in Mesa with LLVM, I'm not sure what's
happening as the problem doesn't manifest when debugging is enabled so I'm not
sure how to create a smaller test case