Don't check for inalloca in IPConstantPropagation

[aeubanks]

Summary

This was added in https://reviews.llvm.org/D2449, but I'm not sure it's
necessary since an inalloca value is never a Constant (should be an
AllocaInst).

[aeubanks]

Wrong version...

[hans]

lgtm

Maybe in the first line of the commit message, make it even clearer that you're removing the check because it's unnecessary. For example, "Remove unnecessary check for inalloca in IPConstantPropagation"

[aeubanks]

In D79350#2019883, @hans wrote:

lgtm

Maybe in the first line of the commit message, make it even clearer that you're removing the check because it's unnecessary. For example, "Remove unnecessary check for inalloca in IPConstantPropagation"

Done.

llvm/lib/Transforms/IPO/IPConstantPropagation.cpp

static bool PropagateConstantsIntoArguments(Function &F) {
 
   // If we got to this point, there is a constant argument!
   assert(NumNonconstant != ArgumentConstants.size());
   bool MadeChange = false;
   Function::arg_iterator AI = F.arg_begin();
   for (unsigned i = 0, e = ArgumentConstants.size(); i != e; ++i, ++AI) {
     // Do we have a constant argument?
     if (ArgumentConstants[i].getInt() || AI->use_empty() ||
-        AI->hasInAllocaAttr() || (AI->hasByValAttr() && !F.onlyReadsMemory()))
+        (AI->hasByValAttr() && !F.onlyReadsMemory()))
       continue;
 
     Value *V = ArgumentConstants[i].getPointer();
     if (!V) V = UndefValue::get(AI->getType());
     AI->replaceAllUsesWith(V);
     ++NumArgumentsProped;
     MadeChange = true;
   }