[llvm] [DirectX] Fixes for generation of DISubprogram (PR #194418)

[Harald van Dijk via llvm-commits]

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@@ -1569,9 +1569,9 @@ void DXILBitcodeWriter::writeDISubprogram(const DISubprogram *N,
   Record.push_back(VE.getMetadataOrNullID(N->getContainingType()));
   Record.push_back(N->getVirtuality());
   Record.push_back(N->getVirtualIndex());
-  Record.push_back(N->getFlags());
+  Record.push_back(N->getFlags() & 0x7fff);
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hvdijk wrote:

This masks off the flags that were not supported in LLVM 3.7, I'll change it to do arithmetic based on the first non-supported flag to make it clearer.

https://github.com/llvm/llvm-project/pull/194418