[llvm-commits] [llvm] r83324 - /llvm/trunk/lib/Analysis/MallocHelper.cpp

[Torok Edwin]

Author: edwin
Date: Mon Oct  5 16:15:43 2009
New Revision: 83324

URL: http://llvm.org/viewvc/llvm-project?rev=83324&view=rev
Log:
Don't treat malloc calls with non-matching prototype as malloc.
Fixes second part of PR5130, miscompilation in FreeBSD kernel, where malloc takes 3 params,
and *does* initialize memory.

Modified:
    llvm/trunk/lib/Analysis/MallocHelper.cpp

Modified: llvm/trunk/lib/Analysis/MallocHelper.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Analysis/MallocHelper.cpp?rev=83324&r1=83323&r2=83324&view=diff

==============================================================================
--- llvm/trunk/lib/Analysis/MallocHelper.cpp (original)
+++ llvm/trunk/lib/Analysis/MallocHelper.cpp Mon Oct  5 16:15:43 2009
@@ -34,12 +34,23 @@
     return false;
 
   const Module* M = CI->getParent()->getParent()->getParent();
-  Constant *MallocFunc = M->getFunction("malloc");
+  Function *MallocFunc = M->getFunction("malloc");
 
   if (CI->getOperand(0) != MallocFunc)
     return false;
 
-  return true;
+  // Check malloc prototype.
+  // FIXME: this will be obsolete when nobuiltin attribute will exist.
+  const FunctionType *FTy = MallocFunc->getFunctionType();
+  if (FTy->getNumParams() != 1)
+    return false;
+  if (IntegerType *ITy = dyn_cast<IntegerType>(FTy->param_begin()->get())) {
+    if (ITy->getBitWidth() != 32 && ITy->getBitWidth() != 64)
+      return false;
+    return true;
+  }
+
+  return false;
 }
 
 /// extractMallocCall - Returns the corresponding CallInst if the instruction