instcombine shouldn't delete all null checks for mallocs.
This fixes PR5130.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@83290 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp
index 561527c..fae8629 100644
--- a/lib/Transforms/Scalar/InstructionCombining.cpp
+++ b/lib/Transforms/Scalar/InstructionCombining.cpp
@@ -5934,9 +5934,9 @@
   
   // icmp <global/alloca*/null>, <global/alloca*/null> - Global/Stack value
   // addresses never equal each other!  We already know that Op0 != Op1.
-  if ((isa<GlobalValue>(Op0) || isa<AllocaInst>(Op0) || isMalloc(Op0) ||
+  if ((isa<GlobalValue>(Op0) || isa<AllocaInst>(Op0) || 
        isa<ConstantPointerNull>(Op0)) &&
-      (isa<GlobalValue>(Op1) || isa<AllocaInst>(Op1) || isMalloc(Op1) ||
+      (isa<GlobalValue>(Op1) || isa<AllocaInst>(Op1) || 
        isa<ConstantPointerNull>(Op1)))
     return ReplaceInstUsesWith(I, ConstantInt::get(Type::getInt1Ty(*Context), 
                                                    !I.isTrueWhenEqual()));