[llvm-dev] Get llvm to optimize through thunk method

[Friedman, Eli via llvm-dev]

On 10/4/2018 1:58 AM, Carlo Kok via llvm-dev wrote:
> Hi,
>
> is there a way I can tell llvm to optimize through a call to a thunk method?
>
> https://gist.github.com/carlokok/3ba9cb1a36a145a3071a7b901867d442
>
> On line 37 I cast & call _intf__rtti_t27_issue81139__static__dispatchtest_d_Test_vmthelper0
>
> which is a thunk method that calls
> _intfstub_mi_t27_issue81139__static__dispatchtest_d_Test4_Test
>
> Is there a way to tell the optimizer to get rid of the thunk call? Since llvm can prove it will end up in _intfstub_mi_t27_issue81139__static__dispatchtest_d_Test4_Test
> given the parameters passed?

LLVM is conservative if the callee of a call is bitcast in a non-trivial 
way; it treats the call as opaque.

What are you trying to accomplish by passing the wrong number of 
arguments to the call?

-Eli

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