[llvm-commits] [llvm] r85706 - in /llvm/trunk: include/llvm/BasicBlock.h lib/VMCore/Globals.cpp lib/VMCore/Verifier.cpp

[Chris Lattner]

Author: lattner
Date: Sat Oct 31 23:08:01 2009
New Revision: 85706

URL: http://llvm.org/viewvc/llvm-project?rev=85706&view=rev
Log:
fix an issue where the verifier would reject a function whose entry
block had its address taken even if the blockaddress was dead.

Modified:
    llvm/trunk/include/llvm/BasicBlock.h
    llvm/trunk/lib/VMCore/Globals.cpp
    llvm/trunk/lib/VMCore/Verifier.cpp

Modified: llvm/trunk/include/llvm/BasicBlock.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/BasicBlock.h?rev=85706&r1=85705&r2=85706&view=diff

==============================================================================
--- llvm/trunk/include/llvm/BasicBlock.h (original)
+++ llvm/trunk/include/llvm/BasicBlock.h Sat Oct 31 23:08:01 2009
@@ -240,6 +240,10 @@
   /// hasAddressTaken - returns true if there are any uses of this basic block
   /// other than direct branches, switches, etc. to it.
   bool hasAddressTaken() const { return SubclassData != 0; }
+                     
+  /// removeDeadBlockAddress - If there is a blockaddress node for this basic
+  /// block, try to remove it and any dead constant users of it.
+  void removeDeadBlockAddress();
 private:
   /// AdjustBlockAddressRefCount - BasicBlock stores the number of BlockAddress
   /// objects using it.  This is almost always 0, sometimes one, possibly but

Modified: llvm/trunk/lib/VMCore/Globals.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/VMCore/Globals.cpp?rev=85706&r1=85705&r2=85706&view=diff

==============================================================================
--- llvm/trunk/lib/VMCore/Globals.cpp (original)
+++ llvm/trunk/lib/VMCore/Globals.cpp Sat Oct 31 23:08:01 2009
@@ -75,6 +75,14 @@
   }
 }
 
+/// removeDeadBlockAddress - If there is a blockaddress node for this basic
+/// block, try to remove it and any dead constant users of it.
+void BasicBlock::removeDeadBlockAddress() {
+  if (!hasAddressTaken()) return;
+  removeDeadUsersOfConstant(BlockAddress::get(this));
+}
+
+
 /// Override destroyConstant to make sure it doesn't get called on
 /// GlobalValue's because they shouldn't be treated like other constants.
 void GlobalValue::destroyConstant() {

Modified: llvm/trunk/lib/VMCore/Verifier.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/VMCore/Verifier.cpp?rev=85706&r1=85705&r2=85706&view=diff

==============================================================================
--- llvm/trunk/lib/VMCore/Verifier.cpp (original)
+++ llvm/trunk/lib/VMCore/Verifier.cpp Sat Oct 31 23:08:01 2009
@@ -658,8 +658,13 @@
     BasicBlock *Entry = &F.getEntryBlock();
     Assert1(pred_begin(Entry) == pred_end(Entry),
             "Entry block to function must not have predecessors!", Entry);
-    Assert1(!Entry->hasAddressTaken(),
-            "blockaddress may not be used with the entry block!", Entry);
+    
+    // The address of the entry block cannot be taken, unless it is dead.
+    if (Entry->hasAddressTaken()) {
+      Entry->removeDeadBlockAddress();
+      Assert1(!Entry->hasAddressTaken(),
+              "blockaddress may not be used with the entry block!", Entry);
+    }
   }
   
   // If this function is actually an intrinsic, verify that it is only used in