diff --git a/include/llvm/CodeGen/Analysis.h b/include/llvm/CodeGen/Analysis.h index ce9ca0a0583..b2cc7047b30 100644 --- a/include/llvm/CodeGen/Analysis.h +++ b/include/llvm/CodeGen/Analysis.h @@ -26,6 +26,7 @@ namespace llvm { class GlobalVariable; class TargetLowering; +class TargetLoweringBase; class SDNode; class SDValue; class SelectionDAG; @@ -88,6 +89,14 @@ ISD::CondCode getICmpCondCode(ICmpInst::Predicate Pred); /// This function only tests target-independent requirements. bool isInTailCallPosition(ImmutableCallSite CS, const TargetLowering &TLI); +/// Test if given that the input instruction is in the tail call position if the +/// return type or any attributes of the function will inhibit tail call +/// optimization. +bool returnTypeIsEligibleForTailCall(const Function *F, + const Instruction *I, + const ReturnInst *Ret, + const TargetLoweringBase &TLI); + } // End llvm namespace #endif diff --git a/lib/CodeGen/Analysis.cpp b/lib/CodeGen/Analysis.cpp index 332a0425514..1600c67a7c6 100644 --- a/lib/CodeGen/Analysis.cpp +++ b/lib/CodeGen/Analysis.cpp @@ -510,6 +510,13 @@ bool llvm::isInTailCallPosition(ImmutableCallSite CS, return false; } + return returnTypeIsEligibleForTailCall(ExitBB->getParent(), I, Ret, TLI); +} + +bool llvm::returnTypeIsEligibleForTailCall(const Function *F, + const Instruction *I, + const ReturnInst *Ret, + const TargetLoweringBase &TLI) { // If the block ends with a void return or unreachable, it doesn't matter // what the call's return type is. if (!Ret || Ret->getNumOperands() == 0) return true; @@ -519,7 +526,7 @@ bool llvm::isInTailCallPosition(ImmutableCallSite CS, if (isa(Ret->getOperand(0))) return true; // Make sure the attributes attached to each return are compatible. - AttrBuilder CallerAttrs(ExitBB->getParent()->getAttributes(), + AttrBuilder CallerAttrs(F->getAttributes(), AttributeSet::ReturnIndex); AttrBuilder CalleeAttrs(cast(I)->getAttributes(), AttributeSet::ReturnIndex);