[llvm] [SandboxVec] SandboxVectorizerIR Boilerplate (PR #189515)

[Jorge Gorbe Moya via llvm-commits]

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@@ -40,7 +40,8 @@ class TargetExtType;
 class VectorType;
 #define DEF_INSTR(ID, OPCODE, CLASS) class CLASS;
 #define DEF_CONST(ID, CLASS) class CLASS;
-#include "llvm/SandboxIR/Values.def"
+#define DEF_DISABLE_AUTO_UNDEF // Since we are including more than one .def.
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slackito wrote:

Nit: I'd replace the comment with `// The file below includes multiple .def files.` or something along that line.

Mostly because if I read "we're including more than one .def" and see only one `#include` directive, I think it's an outdated comment.

https://github.com/llvm/llvm-project/pull/189515