[PATCH] D39973: Fix CaptureTracking for llvm.invariant.group.barrier

[Yaxun Liu via Phabricator via llvm-commits]

yaxunl added inline comments.


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Comment at: lib/Analysis/CaptureTracking.cpp:247
+      // Intrinsic function invariant_group_barrier does not capture pointer.
+      if (isa<IntrinsicInst>(I) && cast<IntrinsicInst>(I)->getIntrinsicID() ==
+                                       Intrinsic::invariant_group_barrier) {
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rampitec wrote:
> rampitec wrote:
> > yaxunl wrote:
> > > rampitec wrote:
> > > > Can we mark it as "NoCapture<0>" instead?
> > > line 243 also checks I->getType()->isVoidTy(), but this intrinsic returns a pointer. So even if we make it NoCapture, it still does not work.
> > Checking for a specific intrinsic seems error-prone. What if the pointer returned by the call is further used in the caller?
> Maybe it is possible to add a check for VoidTy with the condition, that value is unused if returned from non-void?
Good idea. Will do.


https://reviews.llvm.org/D39973