[LLVMdev] SCCP

[Chris Lattner]

On Tue, 9 May 2006, Nick Lewycky wrote:
>>> For an analysis pass, I'm interested in reading the lattice values
>>> calculated by SCCP. Should I split the current SCCP optimization into an
>>> analysis piece and the optimization that depends on it, so that I can
>>> use its analysis results?
>>
>> SCCP is already split into an SCCPSolver class that is used by the SCCP
>> and IPSCCP classes.  You should just be able to use SCCPSolver.  Note
>> that it is not a pass, just a class you can use.
>
> Thanks. I thought SCCPSolver was just a helper. I suppose then I should
> just move its class declaration into a header so it can be seen from
> outside SCCP.cpp. Would creating a new include/llvm/Transforms/SCCP.h be
> the right idea?

You could do that, but SCCPSolver isn't really useful to mainline LLVM for 
anything other than SCCP and IPSCCP, so we don't need it in a public 
header.  Out of curiosity, what are you looking to use the latice values 
for?  Why not just run SCCP and then look at the transformed code?

-Chris

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