[llvm] r320943 - Treat sret arguments as being dereferenceable in getPointerDereferenceableBytes()

[Bjorn Steinbrink via llvm-commits]

Author: bsteinbr
Date: Sun Dec 17 07:11:52 2017
New Revision: 320943

URL: http://llvm.org/viewvc/llvm-project?rev=320943&view=rev
Log:
Treat sret arguments as being dereferenceable in getPointerDereferenceableBytes()

Modified:
    llvm/trunk/lib/IR/Value.cpp

Modified: llvm/trunk/lib/IR/Value.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/IR/Value.cpp?rev=320943&r1=320942&r2=320943&view=diff
==============================================================================
--- llvm/trunk/lib/IR/Value.cpp (original)
+++ llvm/trunk/lib/IR/Value.cpp Sun Dec 17 07:11:52 2017
@@ -627,9 +627,10 @@ uint64_t Value::getPointerDereferenceabl
   CanBeNull = false;
   if (const Argument *A = dyn_cast<Argument>(this)) {
     DerefBytes = A->getDereferenceableBytes();
-    if (DerefBytes == 0 && A->hasByValAttr()) {
+    if (DerefBytes == 0 && (A->hasByValAttr() || A->hasStructRetAttr())) {
       Type *PT = cast<PointerType>(A->getType())->getElementType();
-      DerefBytes = DL.getTypeStoreSize(PT);
+      if (PT->isSized())
+        DerefBytes = DL.getTypeStoreSize(PT);
     }
     if (DerefBytes == 0) {
       DerefBytes = A->getDereferenceableOrNullBytes();