Use Argument::hasAttribute and AttributeList::ReturnIndex more

This eliminates many extra 'Idx' induction variables in loops over
arguments in CodeGen/ and Target/. It also reduces the number of places
where we assume that ReturnIndex is 0 and that we should add one to
argument numbers to get the corresponding attribute list index.

NFC

llvm-svn: 301666

1 files changed, 3 insertions, 2 deletions

diff --git a/llvm/lib/Transforms/IPO/FunctionAttrs.cpp b/llvm/lib/Transforms/IPO/FunctionAttrs.cpp
index 9648883b7f2..031c3d8a9eb 100644
--- a/llvm/lib/Transforms/IPO/FunctionAttrs.cpp
+++ b/llvm/lib/Transforms/IPO/FunctionAttrs.cpp
@@ -855,10 +855,11 @@ static bool addNoAliasAttrs(const SCCNodeSet &SCCNodes) {
 
   bool MadeChange = false;
   for (Function *F : SCCNodes) {
-    if (F->doesNotAlias(0) || !F->getReturnType()->isPointerTy())
+    if (F->doesNotAlias(AttributeList::ReturnIndex) ||
+        !F->getReturnType()->isPointerTy())
       continue;
 
-    F->setDoesNotAlias(0);
+    F->setDoesNotAlias(AttributeList::ReturnIndex);
     ++NumNoAlias;
     MadeChange = true;
   }