Re: CVS commit: src

[Robert Swindells <rjs%fdy2.co.uk@localhost>]

maya%NetBSD.org@localhost wrote:
>On Tue, Jan 01, 2019 at 03:34:47PM +0100, Martin Husemann wrote:
>> On Tue, Jan 01, 2019 at 02:22:54PM +0000, maya%netbsd.org@localhost wrote:
>> > I'm stuck between the hammer and the anvil here.
>> > I'd like NetBSD to use a recent MesaLib, the kind that uses LLVM.
>> 
>> Can you explain how the MesaLib build uses llvm?
>> 
>> This kinda sounds like you need a special build time binary that would
>> live in $TOOLDIR and it is not exactly clear how installing some headers
>> helps building this tool (as you can not assume a NetBSD build host).
>> 
>> Martin
>
>I haven't dug up too much into it in the past, so this was fun to
>discover:
>
>MesaLib is a compiler for turning agnostic representations like GLSL and
>SPIR-V into hardware appropriate ones. It has passes and intermediate
>formats (plural!) and everything.
>
>AMD drivers use LLVM as a step in the process, they defined an AMDGPU as
>a target architecture.
>
>I'm not sure how a JIT works, but swrast uses LLVM for its JIT.
>
>at least on the pkgsrc build, swrast and radeonsi are dynamically linked
>with libLLVM.

How does the usage of libLLVM from MesaLib make use of the LLVM headers
at *runtime* ?

If they are not needed at runtime then why do they need to be installed
on a target machine ?