Add getReturnedArgOperand to Call/InvokeInst, CallSite
In order to make the optimizer smarter about using the 'returned' argument
attribute (generally, but motivated by my llvm.noalias intrinsic work), add a
utility function to Call/InvokeInst, and CallSite, to make it easy to get the
returned call argument (when one exists).
P.S. There is already an unfortunate amount of code duplication between
CallInst and InvokeInst, and this adds to it. We should probably clean that up
separately.
Differential Revision: http://reviews.llvm.org/D22204
llvm-svn: 275031
diff --git a/llvm/lib/IR/Instructions.cpp b/llvm/lib/IR/Instructions.cpp
index 6f60d15..b9c693ff 100644
--- a/llvm/lib/IR/Instructions.cpp
+++ b/llvm/lib/IR/Instructions.cpp
@@ -331,6 +331,19 @@
return NewCI;
}
+Value *CallInst::getReturnedArgOperand() const {
+ unsigned Index;
+
+ if (AttributeList.hasAttrSomewhere(Attribute::Returned, &Index) && Index)
+ return getArgOperand(Index-1);
+ if (const Function *F = getCalledFunction())
+ if (F->getAttributes().hasAttrSomewhere(Attribute::Returned, &Index) &&
+ Index)
+ return getArgOperand(Index-1);
+
+ return nullptr;
+}
+
void CallInst::addAttribute(unsigned i, Attribute::AttrKind Kind) {
AttributeSet PAL = getAttributes();
PAL = PAL.addAttribute(getContext(), i, Kind);
@@ -688,6 +701,19 @@
return setSuccessor(idx, B);
}
+Value *InvokeInst::getReturnedArgOperand() const {
+ unsigned Index;
+
+ if (AttributeList.hasAttrSomewhere(Attribute::Returned, &Index) && Index)
+ return getArgOperand(Index-1);
+ if (const Function *F = getCalledFunction())
+ if (F->getAttributes().hasAttrSomewhere(Attribute::Returned, &Index) &&
+ Index)
+ return getArgOperand(Index-1);
+
+ return nullptr;
+}
+
bool InvokeInst::paramHasAttr(unsigned i, Attribute::AttrKind Kind) const {
assert(i < (getNumArgOperands() + 1) && "Param index out of bounds!");