PR4286: Make RewriteLoadUserOfWholeAlloca and
RewriteStoreUserOfWholeAlloca deal with tail padding because
isSafeUseOfBitCastedAllocation expects them to. Otherwise, we crash
trying to erase the bitcast.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72688 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Scalar/ScalarReplAggregates.cpp b/lib/Transforms/Scalar/ScalarReplAggregates.cpp
index 5e2859a..9935f12 100644
--- a/lib/Transforms/Scalar/ScalarReplAggregates.cpp
+++ b/lib/Transforms/Scalar/ScalarReplAggregates.cpp
@@ -903,11 +903,13 @@
// If this isn't a store of an integer to the whole alloca, it may be a store
// to the first element. Just ignore the store in this case and normal SROA
- // will handle it. We don't handle types here that have tail padding, like
- // an alloca of type {i1}.
+ // will handle it.
if (!isa<IntegerType>(SrcVal->getType()) ||
- TD->getTypeSizeInBits(SrcVal->getType()) != AllocaSizeBits)
+ TD->getTypeAllocSizeInBits(SrcVal->getType()) != AllocaSizeBits)
return;
+ // Handle tail padding by extending the operand
+ if (TD->getTypeSizeInBits(SrcVal->getType()) != AllocaSizeBits)
+ SrcVal = new ZExtInst(SrcVal, IntegerType::get(AllocaSizeBits), "", SI);
DOUT << "PROMOTING STORE TO WHOLE ALLOCA: " << *AI << *SI;
@@ -1016,10 +1018,9 @@
// If this isn't a load of the whole alloca to an integer, it may be a load
// of the first element. Just ignore the load in this case and normal SROA
- // will handle it. We don't handle types here that have tail padding, like
- // an alloca of type {i1}.
+ // will handle it.
if (!isa<IntegerType>(LI->getType()) ||
- TD->getTypeSizeInBits(LI->getType()) != AllocaSizeBits)
+ TD->getTypeAllocSizeInBits(LI->getType()) != AllocaSizeBits)
return;
DOUT << "PROMOTING LOAD OF WHOLE ALLOCA: " << *AI << *LI;
@@ -1035,7 +1036,7 @@
ArrayEltBitOffset = TD->getTypeAllocSizeInBits(ArrayEltTy);
}
- Value *ResultVal = Constant::getNullValue(LI->getType());
+ Value *ResultVal = Constant::getNullValue(IntegerType::get(AllocaSizeBits));
for (unsigned i = 0, e = NewElts.size(); i != e; ++i) {
// Load the value from the alloca. If the NewElt is an aggregate, cast
@@ -1082,7 +1083,11 @@
ResultVal = BinaryOperator::CreateOr(SrcField, ResultVal, "", LI);
}
-
+
+ // Handle tail padding by truncating the result
+ if (TD->getTypeSizeInBits(LI->getType()) != AllocaSizeBits)
+ ResultVal = new TruncInst(ResultVal, LI->getType(), "", LI);
+
LI->replaceAllUsesWith(ResultVal);
LI->eraseFromParent();
}