[llvm] [ObjCopy][DX] Support for -dump-section flag (PR #159999)

[James Henderson via llvm-commits]

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@@ -0,0 +1,283 @@
+# RUN: yaml2obj %s -o %t.dxbc
+# RUN: llvm-objcopy --dump-section=DXIL=%t.bc %t.dxbc
+# RUN: llvm-dis %t.bc -o - | FileCheck %s
+# RUN: wc -c %t.bc | FileCheck %s --check-prefix=DXIL-SIZE
+
+# Verify that when dumping the DXIL part we get a valid bitcode file.
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jh7370 wrote:

Newer tests in the tools prefer double comment markers for true comments, to help them stand out from the lit and FileCheck directives:
```suggestion
## Verify that when dumping the DXIL part we get a valid bitcode file.
```
Applies throughout the tests.

https://github.com/llvm/llvm-project/pull/159999