[clang] [llvm] [SystemZ] Add i128 support for z/OS XPLINK64 ABI (PR #223026)

[Ulrich Weigand via cfe-commits]

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@@ -1,26 +1,35 @@
 
 // RUN: %clang -target s390x-unknown-linux-gnu %s -### -o %t.o 2>&1 | FileCheck -check-prefix=CHECK-DEFAULT %s
+// RUN: %clang -target s390x-ibm-zos %s -### -o %t.o 2>&1 | FileCheck -check-prefix=CHECK-DEFAULT %s
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uweigand wrote:

These extra test runs are probably a good idea, but this isn't really related to this change, so these (both systemz-features.cpp and zvector.c) should go into a separate PR.

https://github.com/llvm/llvm-project/pull/223026