[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 #14 from Mike Lothian <mike at fireburn dot co.uk> ---
I've been playing around with GCC 7.2.0 again

When compiling a 32bit LLVM with -O2 -march=native, llvm-tblgen runs
indefinitely during the build so it never completes

Doing the same with -O2 -march=native -mno-bmi or using GCC 6.4.0 allows it to
build 

From what I can see llvm-tblgen is a C++ program