[llvm] [IR] Use immarg for preallocated intrinsics (NFC) (PR #155835)

[Matt Arsenault via llvm-commits]

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@@ -65,7 +65,7 @@ define void @preallocated_one_call() {
     ret void
 }
 
-; CHECK: must be a constant
+; CHECK: immarg operand has non-immediate parameter
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arsenm wrote:

Missing test for the call_preallocated_arg case?

https://github.com/llvm/llvm-project/pull/155835