[clang] [CIR] Implement initial LoweringPrepare support for global ctors (PR #161452)

[Bruno Cardoso Lopes via cfe-commits]

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@@ -20,6 +20,10 @@
 
 #include "clang/CIR/Interfaces/CIRTypeInterfaces.h"
 
+namespace cir {
+inline constexpr uint32_t DefaultGlobalCtorDtorPriority = 65535;
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bcardosolopes wrote:

I don't think we need this: (a) it's not used in this PR and (b) can be done in tablegen level by assigning a default value for priorities.

https://github.com/llvm/llvm-project/pull/161452