[llvm] [DXIL] Add support for root signature flag element in DXContainer (PR #123147)

[Justin Bogner via llvm-commits]

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@@ -0,0 +1,18 @@
+; RUN: not opt -passes='print<dxil-root-signature>' %s -S -o - 2>&1 | FileCheck %s
+
+target triple = "dxil-unknown-shadermodel6.0-compute"
+
+; CHECK: error: Invalid format for Root Signature Definition. Pairs of function, root signature expected.
+; CHECK-NO: Root Signature Definitions
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bogner wrote:

typo? `CHECK-NO` doesn't do anything.
```suggestion
; CHECK-NOT: Root Signature Definitions
```

this comes up in a few of the tests.

https://github.com/llvm/llvm-project/pull/123147