[LLVMdev] is there some canonical way to extend liveness?

[Matt Arsenault]

> On Feb 17, 2015, at 12:46 PM, Andy Ayers <andya at microsoft.com> wrote:
> 
> In other compilers I’ve worked on there were special pseudo instructions (or similar mechanisms like adding extra source operands to returns) that allowed you to artificially extend lifetimes of values. For instance we might have a requirement that a certain local (say the ‘this pointer’) remain live throughout the method.
>  
> Is there anything like this in LLVM?
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There isn’t a generic mechanism for this, but SI uses a custom pass and pseudos to accomplish this. See lib/Target/R600/SIFixSGPRLiveRanges.cpp
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