Rewrite uw_install_context without function calls to avoid register
spilling in _Unwind_RaiseException during return context installation.
2020-06-08 Max Filippov <jcmvbkbc@gmail.com>
gcc/testsuite/
* g++.target/xtensa/pr95571.C: New test.
* g++.target/xtensa/xtensa.exp: New testsuite.
libgcc/
* config/xtensa/unwind-dw2-xtensa.c (uw_install_context): Merge
with uw_install_context_1.