[stackprotector] Refactor out the end of isInTailCallPosition into the function returnTypeIsEligibleForTailCall.

This allows me to use returnTypeIsEligibleForTailCall in the stack protector pass.

rdar://13935163

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188765 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Michael Gottesman 2013-08-20 08:36:50 +00:00
parent 1a6de17273
commit 9d6852cf98
2 changed files with 17 additions and 1 deletions

View File

@ -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

View File

@ -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<UndefValue>(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<CallInst>(I)->getAttributes(),
AttributeSet::ReturnIndex);