[llvm-dev] PlaceSafepoints, operand bundles, and RewriteStatepointsForGC

[Sanjoy Das via llvm-dev]

[+CC llvm-dev this time]

Hi,

As discussed in the review thread in http://reviews.llvm.org/D16439,
the future plan around statepoints, deopt bundles, PlaceSafepoints
etc. is to "constant fold" -spp-no-statepoints
and -rs4gc-use-deopt-bundles to true.

We (Azul) have moved to a representation of safepoint polls, deopt
state etc. that enables us to do the above; and at this point I'm
waiting for an okay from you guys.  LLILC should mostly Just Work in
this new world, with the exception of gc transition operands -- the
LLILC frontend will have to denote these using "gc-transition" operand
bundles, and not by eagerly emitting gc.statepoint calls.  You should
be able to test out your changes by passing in -spp-no-statepoints
and -rs4gc-use-deopt-bundles to the LLVM build used in LLILC.

Please let me know once you're okay with me making the switch to
-spp-no-statepoints and -rs4gc-use-deopt-bundles being clamped to
true.

-- Sanjoy