[llvm] [ORC] Add signext on @sum() arguments in test. (PR #113308)

[Lang Hames via llvm-commits]

================
@@ -90,6 +90,35 @@ class OrcCAPITestBase : public testing::Test {
 
     LLVMOrcDisposeLLJIT(J);
     TargetSupported = true;
+
+    // Create test functions in text format, with the proper extension
+    // attributes.
+    if (SumExample.empty()) {
+      std::string I32RetExt = "";
+      std::string I32ArgExt = "";
+      if (StringRef(TargetTriple).starts_with("s390x-ibm-linux"))
+        I32RetExt = I32ArgExt = "signext ";
----------------
lhames wrote:

Is there a way that we could move this out into a common header location that could be used elsewhere in LLVM, or at least in the tests?

E.g.
```c++
StringRef getExtension(const Triple &TT) {
  switch (TT.getArch()) {
  case Triple::s390x:
    if (TT.getVendor() == Triple::IBM && TT.getOS() == Triple::Linux)
      return "signext ";
    break;
  default:
    break;
  }
  return "";
}
```

I'm guessing that we'll need this for Kaleidoscope and some other examples and tests too?

https://github.com/llvm/llvm-project/pull/113308