[PATCH] Lower invoke statepoints and gc.results tied to them.

[Philip Reames]

Comments inline.

You need tests for this.

Also, your code appears to have handling for gc.result even though your description says that's not handled.  Which is it?


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  rL LLVM

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Comment at: lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp:1048
@@ +1047,3 @@
+  SDValue copyFromReg = getCopyFromRegs(V, V->getType());
+  if (copyFromReg.getNode()) {
+    return copyFromReg;
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I'm a bit uncomfortable signing off on this part of the change since I'm unfamiliar with the details of the codepath.  I'll ask that you wait for a signoff from someone more familiar with SelectionDAG as a whole.  

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Comment at: lib/CodeGen/SelectionDAG/StatepointLowering.cpp:257
@@ +256,3 @@
+      // so we need to export it now.
+      unsigned reg = Builder.FuncInfo.CreateRegs(Tmp->getType());
+      Builder.CopyValueToVirtualRegister(Tmp, reg);
----------------
I'm still confused about why we need this.  Why doesn't the standard export mechanism work here?  Simply producing the value and letting it be exported normally seems like it would work?

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Comment at: lib/CodeGen/SelectionDAG/StatepointLowering.cpp:297
@@ -277,2 +296,3 @@
   int Sanity = 0;
   while (CallEnd->getOpcode() != ISD::CALLSEQ_END) {
+    assert(CallEnd->getNumOperands() >= 1 &&
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Just to be clear, the reason for this is that CallEnd might start with the eh_label which doesn't have a glue node?  

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Comment at: lib/CodeGen/SelectionDAG/StatepointLowering.cpp:669
@@ +668,3 @@
+    // and getValue() will use CopyFromReg of the wrong type (always i32 in our case)
+    PointerType *calleeType = cast<PointerType>(
+                                ImmutableStatepoint(I).actualCallee()->getType());
----------------
Doesn't this depend on what SDValue we set for a specific instruction?   As above, I'm not convinced this is necessary.

Also, CamelCase naming per llvm docs.

http://reviews.llvm.org/D7760

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