[SelectionDAGBuilder] Adds support for landingpads of token type

Summary: This patch adds a check in visitLandingPad to see if landingpad's result type is token type. If so, do not create DAG nodes for its exception pointer and selector value. This patch enables the back end to handle landingpads of token type.

Reviewers: JosephTremoulet, majnemer, rnk

Subscribers: sanjoy, llvm-commits

Differential Revision: http://reviews.llvm.org/D15405

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@255749 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp

@@ -2177,6 +2177,13 @@ void SelectionDAGBuilder::visitLandingPad(const LandingPadInst &LP) {
       TLI.getExceptionSelectorRegister(PersonalityFn) == 0)
     return;
 
+  // If landingpad's return type is token type, we don't create DAG nodes
+  // for its exception pointer and selector value. The extraction of exception
+  // pointer or selector value from token type landingpads is not currently
+  // supported.
+  if (LP.getType()->isTokenTy())
+    return;
+
   SmallVector<EVT, 2> ValueVTs;
   SDLoc dl = getCurSDLoc();
   ComputeValueVTs(TLI, DAG.getDataLayout(), LP.getType(), ValueVTs);

test/CodeGen/X86/inconsistent_landingpad.ll

@@ -0,0 +1,30 @@
+; RUN: not llvm-as -disable-output <%s 2>&1 | FileCheck %s
+
+define void @test() personality i32 (...)* @dummy_personality {
+; CHECK: The landingpad instruction should have a consistent result type inside a function
+entry:
+  invoke void @dummy1()
+          to label %next unwind label %unwind1
+
+unwind1:
+  %lp1 = landingpad token
+            cleanup
+  br label %return
+
+next:
+  invoke void @dummy2()
+          to label %return unwind label %unwind2
+
+unwind2:
+  %lp2 = landingpad { i8*, i32 }
+            cleanup
+  br label %return
+
+return:
+  ret void
+}
+
+declare void @dummy1()
+declare void @dummy2()
+
+declare i32 @dummy_personality(...)

test/CodeGen/X86/token_landingpad.ll

@@ -0,0 +1,22 @@
+; RUN: llc < %s | FileCheck %s
+
+; This test verifies that SelectionDAG can handle landingPad of token type.
+
+define void @test() personality i32 (...)* @dummy_personality {
+; CHECK: .cfi_personality 155, _dummy_personality
+entry:
+  invoke void @dummy()
+          to label %return unwind label %unwind
+
+unwind:                                           ; preds = %entry
+  %lp = landingpad token
+            cleanup
+  br label %return
+
+return:                                           ; preds = %entry
+  ret void
+}
+
+declare void @dummy()
+
+declare i32 @dummy_personality(...)