[llvm] SystemZ: Add some tests for fp128 atomics with soft-float (PR #90826)

[Ulrich Weigand via llvm-commits]

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@@ -5,13 +5,23 @@
 ; RUN: llc < %s -mtriple=s390x-linux-gnu | FileCheck -check-prefixes=CHECK,BASE %s
 ; RUN: llc < %s -mtriple=s390x-linux-gnu -mcpu=z13 | FileCheck -check-prefixes=CHECK,Z13 %s
 
+; TODO: Is it worth testing softfp with vector?
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uweigand wrote:

softfp disables use of vector registers as well as FP registers (since vector registers partially overlap FP registers).  Therefore, with softfp vector support shouldn't make any difference.  It might still be useful to add another RUN line with the same checks to validate that.

https://github.com/llvm/llvm-project/pull/90826