[Statepoints] Let patchable statepoints have a symbolic call target.

Summary:
As added initially, statepoints required their call targets to be a
constant pointer null if ``numPatchBytes`` was non-zero.  This turns out
to be a problem ergonomically, since there is no way to mark patchable
statepoints as calling a (readable) symbolic value.

This change remove the restriction of requiring ``null`` call targets
for patchable statepoints, and changes PlaceSafepoints to maintain the
symbolic call target through its transformation.

Reviewers: reames, swaroop.sridhar

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D11550

llvm-svn: 243502

1 files changed, 2 insertions, 7 deletions

diff --git a/llvm/lib/Transforms/Scalar/PlaceSafepoints.cpp b/llvm/lib/Transforms/Scalar/PlaceSafepoints.cpp
index 366301ad731..098e6eff15f 100644
--- a/llvm/lib/Transforms/Scalar/PlaceSafepoints.cpp
+++ b/llvm/lib/Transforms/Scalar/PlaceSafepoints.cpp
@@ -917,15 +917,10 @@ static Value *ReplaceWithStatepoint(const CallSite &CS, /* to replace */
       CS.getInstruction()->getContext(), AttributeSet::FunctionIndex,
       AttrsToRemove);
 
-  Value *StatepointTarget = NumPatchBytes == 0
-                                ? CS.getCalledValue()
-                                : ConstantPointerNull::get(cast<PointerType>(
-                                      CS.getCalledValue()->getType()));
-
   if (CS.isCall()) {
     CallInst *ToReplace = cast<CallInst>(CS.getInstruction());
     CallInst *Call = Builder.CreateGCStatepointCall(
-        ID, NumPatchBytes, StatepointTarget,
+        ID, NumPatchBytes, CS.getCalledValue(),
         makeArrayRef(CS.arg_begin(), CS.arg_end()), None, None,
         "safepoint_token");
     Call->setTailCall(ToReplace->isTailCall());
@@ -951,7 +946,7 @@ static Value *ReplaceWithStatepoint(const CallSite &CS, /* to replace */
     // original block.
     Builder.SetInsertPoint(ToReplace->getParent());
     InvokeInst *Invoke = Builder.CreateGCStatepointInvoke(
-        ID, NumPatchBytes, StatepointTarget, ToReplace->getNormalDest(),
+        ID, NumPatchBytes, CS.getCalledValue(), ToReplace->getNormalDest(),
         ToReplace->getUnwindDest(), makeArrayRef(CS.arg_begin(), CS.arg_end()),
         None, None, "safepoint_token");