[llvm-dev] Finding live values

[Sanjoy Das via llvm-dev]

Hi Rob,

On Thu, Mar 24, 2016 at 12:35 PM, Rob Lyerly via llvm-dev
<llvm-dev at lists.llvm.org> wrote:
> Hi everyone,

> I'm writing a pass that inserts the llvm.experimental.stackmap
> intrinsic into the IR, and I'd like to record the locations of *all*
> live values whenever I insert the intrinsic (all this entails is

What is your definition of a live value?  Some more context on what
you intend to do with stackmaps will be helpful too.

LLVM has a restricted form of a live value analysis that in the
RewriteStatepointsForGC pass, and its intended use is to rewrite LLVM
IR in a way that it can work with a precise compacting garbage
collector; but it looks like you want something more general?

> adding values as arguments to the intrinsic).  Is there any
> pre-existing analysis pass which can give me the live values at a
> given instruction in a basic block?  Or do I need to write an analysis
> pass to calculate this information?

-- Sanjoy