[llvm-commits] [llvm] r121170 - /llvm/trunk/lib/VMCore/Function.cpp

[Dan Gohman]

Author: djg
Date: Tue Dec  7 13:56:51 2010
New Revision: 121170

URL: http://llvm.org/viewvc/llvm-project?rev=121170&view=rev
Log:
Remove the code from Function::dropAllReferences which replaced
uses of the function's blocks with undef. This code isn't needed,
because BasicBlock's destructor handles such uses. Also, undef isn't
correct, since blockaddresses may still be used for comparisons
with null.

Modified:
    llvm/trunk/lib/VMCore/Function.cpp

Modified: llvm/trunk/lib/VMCore/Function.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/VMCore/Function.cpp?rev=121170&r1=121169&r2=121170&view=diff
==============================================================================
--- llvm/trunk/lib/VMCore/Function.cpp (original)
+++ llvm/trunk/lib/VMCore/Function.cpp Tue Dec  7 13:56:51 2010
@@ -227,19 +227,10 @@
   for (iterator I = begin(), E = end(); I != E; ++I)
     I->dropAllReferences();
   
-  // Delete all basic blocks.
-  while (!BasicBlocks.empty()) {
-    // If there is still a reference to the block, it must be a 'blockaddress'
-    // constant pointing to it.  Just replace the BlockAddress with undef.
-    BasicBlock *BB = BasicBlocks.begin();
-    if (!BB->use_empty()) {
-      BlockAddress *BA = cast<BlockAddress>(BB->use_back());
-      BA->replaceAllUsesWith(UndefValue::get(BA->getType()));
-      BA->destroyConstant();
-    }
-    
-    BB->eraseFromParent();
-  }
+  // Delete all basic blocks. They are now unused, except possibly by
+  // blockaddresses, but BasicBlock's destructor takes care of those.
+  while (!BasicBlocks.empty())
+    BasicBlocks.begin()->eraseFromParent();
 }
 
 void Function::addAttribute(unsigned i, Attributes attr) {