[llvm-dev] How to insert instructions before each function calls?

[Dean Michael Berris via llvm-dev]

> On 5 Sep 2016, at 16:14, SHUCAI YAO <yaos4 at mcmaster.ca> wrote:
> 
> 
> Hi Dean,
> 
> Do you have any example for this?  I would like have a look at how you handle this in XRay if it is possible. 
> 

Yes, this is all upstream -- if you look in lib/CodeGen/XRayInstrument.cpp and the associated lowering code for X86 in lib/Target/X86/X86MCInstLower.cpp and/or search for PATCHABLE_RET in include/... and lib/... then that should give you a better idea of how this works. :)

Cheers

-- Dean