[clang] [llvm] [SystemZ] Add support for __builtin_setjmp and __builtin_longjmp (PR #116642)

[Ulrich Weigand via cfe-commits]

================
@@ -0,0 +1,145 @@
+; Simulate register pressure  around setjmp call for double precision arguments.
----------------
uweigand wrote:

Register pressure may indeed be a good reason to have a longer test.  Still, the CHECK statements should be auto-generated.  Also, even here we should be removing unnecessary attributes and annotations that are not essential to the purpose of the test.

https://github.com/llvm/llvm-project/pull/116642