[LLVMdev] Why do LLVM and GCC differ in the position of the frame pointer for ARM?

Tim Northover
Thu, 16 Jan 2014 11:43:55 -0000

Hi Keith,

> So my question is whether there a reason for this difference in where the
> frame pointer points between code generated by LLVM and GCC, or have I
> missed something obvious?

Looks like a bug somewhere to me. Have you checked that the GCC folks
consider it a feature, because their choice is truly ridiculous:
aarch64 (in the AAPCS!), iOS and gnueabi all make fp point to the
first of the two parts of the frame record.

Cheers.

Tim.