[clang] [KeyInstr][Clang][NFC] Don't set -dwarf-use-key-instructions (PR #144115)

[Jeremy Morse via cfe-commits]

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@@ -8,8 +8,14 @@
 // HELP-NOT: key-instructions
 
 // KEY-INSTRUCTIONS: "-gkey-instructions"
-// KEY-INSTRUCTIONS: "-mllvm" "-dwarf-use-key-instructions"
 
 // NO-KEY-INSTRUCTIONS-NOT: key-instructions
 
-//// TODO: Add smoke test once some functionality has been added.
+// RUN %clang %s | FileCheck %s --check-prefix=SMOKETEST-OFF
+void f() {}
+// SMOKETEST-OFF-NOT: keyInstructions
+// SMOKETEST-OFF-NOT: atomGroup
+
+// RUN %clang %s -gkey-instructions | FileCheck %s --check-prefix=SMOKETEST-ON
+// SMOKETEST-ON: keyInstructions: true
+// SMOKETEST-ON: atomGroup: 1
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jmorse wrote:

Is `-gkey-instructions` turning `-g` on as well; would it not be better to explicitly pass `-g` in both cases anyway?

https://github.com/llvm/llvm-project/pull/144115