[llvm] [DirectX] Add `extract-section` to `llvm-objcopy` and implement it for `DXContainer` (PR #154804)

[James Henderson via llvm-commits]

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@@ -1,35 +1,38 @@
 ## Tests that a separate DXContainer is created with only the specified section
-## for each --extract-section specified
+## for each --extract-section specified.
 
 # RUN: yaml2obj %s -o %t
 # RUN: llvm-objcopy %t --extract-section=FKE1=%t.fke1.out --extract-section=FKE4=%t.fke4.out
 # RUN: obj2yaml %t.fke1.out | FileCheck %s --check-prefixes=CHECK,FKE1
 # RUN: obj2yaml %t.fke4.out | FileCheck %s --check-prefixes=CHECK,FKE4
 
+# FKE1:       FileSize:       52
+# FKE4:       FileSize:       1732
+# CHECK-NEXT: PartCount:     1
+# CHECK-NEXT: PartOffsets:   [ 36 ]
+# CHECK-NEXT: Parts:
+
+# CHECK-NOT: FKE0
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jh7370 wrote:

Could we use `--implicit-check-not=Name:` or similar to ensure all Parts have been checked (and therefore there are no other ones)?

https://github.com/llvm/llvm-project/pull/154804