[PATCH] LangRef: va_arg doesn't work on X86_64; update example

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1

Provide a full-fledged example of working variable arguments on X86_64,
since it's easily the most popular platform.

Signed-off-by: Ramkumar Ramachandra <artagnon@gmail.com>

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Hi Ramkumar,

Provide a full-fledged example of working variable arguments on X86_64,
since it's easily the most popular platform.

I don't think this is a good idea. The section is about all the
varargs intrinsics and instructions, so the example should use all of
them even if it does have to use a target other than x86_64.

Also, a single example of x86's va_arg handling isn't going to be very
enlightening for anyone: either you know the ABI and it's just the
"obvious" LLVM IR, or you don't and you won't have a clue what's going
on. It's a rather complex and initially confusing topic, and would
probably deserve its own article if it's going to be documented.

Cheers.

Tim.

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Hi Ramkumar,

> Provide a full-fledged example of working variable arguments on X86_64,
> since it's easily the most popular platform.

I don't think this is a good idea. The section is about all the
varargs intrinsics and instructions, so the example should use all of
them even if it does have to use a target other than x86_64.

Also, a single example of x86's va_arg handling isn't going to be very
enlightening for anyone: either you know the ABI and it's just the
"obvious" LLVM IR, or you don't and you won't have a clue what's going
on. It's a rather complex and initially confusing topic, and would
probably deserve its own article if it's going to be documented.

I agree.

-- Sean Silva