[clang] [CIR] Add basic support for operator new (PR #145802)

[Erich Keane via cfe-commits]

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@@ -95,6 +95,7 @@ CIRGenModule::CIRGenModule(mlir::MLIRContext &mlirContext,
   // TODO(CIR): Should be updated once TypeSizeInfoAttr is upstreamed
   const unsigned sizeTypeSize =
       astContext.getTypeSize(astContext.getSignedSizeType());
+  SizeSizeInBytes = astContext.toCharUnitsFromBits(sizeTypeSize).getQuantity();
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erichkeane wrote:

This concerns me, we're setting 1 half of the union, but only adding accessor for the other side?

https://github.com/llvm/llvm-project/pull/145802