[LLVMdev] Alloca Outside of Entry Block
eli.friedman at gmail.com
Thu Aug 14 09:30:03 PDT 2008
On Thu, Aug 14, 2008 at 7:55 AM, John Criswell <criswell at uiuc.edu> wrote:
> Thanks everyone for the answers. My original question was referring to
> the LLVM IR and not standard C.
> So, the consensus seems to be that it is legal, which makes sense since
> LLVM supports the C alloca function.
Yeah, legal, but the performance sucks because it codegens into a call
to the C library's alloca function.
It's probably worth documenting in LangRef because the difference in
the generated code is so striking.
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