[CallBase] Add hasRetAttr version that takes StringRef.

[fhahn]

Summary

This makes it slightly easier to deal with custom attributes and
CallBase already provides hasFnAttr versions that support both AttrKind
and StringRef arguments in a similar fashion.

[fhahn]

ping :)

[jdoerfert]

LGTM, nits.

llvm/include/llvm/IR/InstrTypes.h

1559

Duplicate the docs.

2240

doc please.

[fhahn]

In D92567#2445945, @jdoerfert wrote:

LGTM, nits.

Thanks, I'll add the comments.

llvm/include/llvm/IR/InstrTypes.h

public:
   /// attributes.
   void addDereferenceableOrNullAttr(unsigned i, uint64_t Bytes) {
     AttributeList PAL = getAttributes();
     PAL = PAL.addDereferenceableOrNullAttr(getContext(), i, Bytes);
     setAttributes(PAL);
   }
 
   /// Determine whether the return value has the given attribute.
-  bool hasRetAttr(Attribute::AttrKind Kind) const;
+  bool hasRetAttr(Attribute::AttrKind Kind) const {
+    return hasRetAttrImpl(Kind);
+  }
+  /// Determine whether the return value has the given attribute.
+  bool hasRetAttr(StringRef Kind) const { return hasRetAttrImpl(Kind); }
 
   /// Determine whether the argument or parameter has the given attribute.
   bool paramHasAttr(unsigned ArgNo, Attribute::AttrKind Kind) const;
 
   /// Get the attribute of a given kind at a position.
   Attribute getAttribute(unsigned i, Attribute::AttrKind Kind) const {
     return getAttributes().getAttribute(i, Kind);
   }
template <typename AttrKind> bool hasFnAttrImpl(AttrKind Kind) const {
 
     // Operand bundles override attributes on the called function, but don't
     // override attributes directly present on the call instruction.
     if (isFnAttrDisallowedByOpBundle(Kind))
       return false;
 
     return hasFnAttrOnCalledFunction(Kind);
   }
+
+  /// Determine whether the return value has the given attribute. Supports
+  /// Attribute::AttrKind and StringRef as \p AttrKind types.
+  template <typename AttrKind> bool hasRetAttrImpl(AttrKind Kind) const {
+    if (Attrs.hasAttribute(AttributeList::ReturnIndex, Kind))
+      return true;
+
+    // Look at the callee, if available.
+    if (const Function *F = getCalledFunction())
+      return F->getAttributes().hasAttribute(AttributeList::ReturnIndex, Kind);
+    return false;
+  }
 };
 
 template <>
 struct OperandTraits<CallBase> : public VariadicOperandTraits<CallBase, 1> {};
 
 DEFINE_TRANSPARENT_OPERAND_ACCESSORS(CallBase, Value)
 
 //===----------------------------------------------------------------------===//

llvm/lib/IR/Instructions.cpp

Value *CallBase::getReturnedArgOperand() const {
   if (const Function *F = getCalledFunction())
     if (F->getAttributes().hasAttrSomewhere(Attribute::Returned, &Index) &&
         Index)
       return getArgOperand(Index - AttributeList::FirstArgIndex);
 
   return nullptr;
 }
 
-bool CallBase::hasRetAttr(Attribute::AttrKind Kind) const {
-  if (Attrs.hasAttribute(AttributeList::ReturnIndex, Kind))
-    return true;
-
-  // Look at the callee, if available.
-  if (const Function *F = getCalledFunction())
-    return F->getAttributes().hasAttribute(AttributeList::ReturnIndex, Kind);
-  return false;
-}
-
 /// Determine whether the argument or parameter has the given attribute.
 bool CallBase::paramHasAttr(unsigned ArgNo, Attribute::AttrKind Kind) const {
   assert(ArgNo < getNumArgOperands() && "Param index out of bounds!");
 
   if (Attrs.hasParamAttribute(ArgNo, Kind))
     return true;
   if (const Function *F = getCalledFunction())
     return F->getAttributes().hasParamAttribute(ArgNo, Kind);

llvm/unittests/IR/InstructionsTest.cpp

TEST_F(ModuleWithFunctionTest, CallInst) {
 
   // Make sure iteration over a call's arguments works as expected.
   unsigned Idx = 0;
   for (Value *Arg : Call->arg_operands()) {
     EXPECT_EQ(FArgTypes[Idx], Arg->getType());
     EXPECT_EQ(Call->getArgOperand(Idx)->getType(), Arg->getType());
     Idx++;
   }
+
+  Call->addAttribute(llvm::AttributeList::ReturnIndex,
+                     Attribute::get(Call->getContext(), "test-str-attr"));
+  EXPECT_TRUE(Call->hasRetAttr("test-str-attr"));
+  EXPECT_FALSE(Call->hasRetAttr("not-on-call"));
 }
 
 TEST_F(ModuleWithFunctionTest, InvokeInst) {
   BasicBlock *BB1 = BasicBlock::Create(Ctx, "", F);
   BasicBlock *BB2 = BasicBlock::Create(Ctx, "", F);
 
   Value *Args[] = {ConstantInt::get(Type::getInt8Ty(Ctx), 20),
                    ConstantInt::get(Type::getInt32Ty(Ctx), 9999),