[LLVMdev] Evaluation of offsetof() macro

[Vadim Chugunov]

Hi!
LLVM has a class, ConstantExpr, that is very handy for compile-time
evaluation of const expressions.   Unfortunately I cannot find any methods
in it that would be helpful in evaluation of expressions similar to this:
(uintptr_t)(&(*(TYPE*)0).FIELD), which is basically the implementation of
the offsetof(TYPE, FIELD) macro.  Specifically, there seem to be no
provisions for dereferencing a pointer.

Does LLVM have any facilities (that I missed), that would help language
front-ends in dealing with this sort of expressions?
Obviously, clang does it somehow, but so far I was not able to locate the
relevant bit of code.  Any pointers would be appreciated!

Vadim
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