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

[James Henderson via llvm-commits]

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@@ -0,0 +1,56 @@
+## Tests that a separate DXContainer is created with only the specified section
+## 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
+
+--- !dxcontainer
+Header:
+  Hash:            [ 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0,
+                     0x0, 0x0, 0x0, 0x0, 0x0, 0x0 ]
+  Version:
+    Major:           1
+    Minor:           0
+## FKE1: FileSize:       52
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jh7370 wrote:

Similar comments to above. I'd move the CHECKs out of the YAML. (You don't need to do the full detail testing that I suggested otherwise though).

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