From 0cc2b61943ab3e4e91e831c6fe6061882f81ec09 Mon Sep 17 00:00:00 2001 From: Johannes Doerfert Date: Sun, 13 Oct 2019 21:25:53 +0000 Subject: [Attributor] Shortcut no-return through will-return No-return and will-return are exclusive, assuming the latter is more prominent we can avoid updates of the former unless will-return is not known for sure. llvm-svn: 374739 --- llvm/lib/Transforms/IPO/Attributor.cpp | 19 +++++++++++-------- 1 file changed, 11 insertions(+), 8 deletions(-) (limited to 'llvm/lib/Transforms') diff --git a/llvm/lib/Transforms/IPO/Attributor.cpp b/llvm/lib/Transforms/IPO/Attributor.cpp index 7dfc802179c..ce720e4aff7 100644 --- a/llvm/lib/Transforms/IPO/Attributor.cpp +++ b/llvm/lib/Transforms/IPO/Attributor.cpp @@ -2859,6 +2859,14 @@ struct AAAlignCallSiteReturned final : AAAlignImpl { struct AANoReturnImpl : public AANoReturn { AANoReturnImpl(const IRPosition &IRP) : AANoReturn(IRP) {} + /// See AbstractAttribute::initialize(...). + void initialize(Attributor &A) override { + AANoReturn::initialize(A); + Function *F = getAssociatedFunction(); + if (!F || F->hasFnAttribute(Attribute::WillReturn)) + indicatePessimisticFixpoint(); + } + /// See AbstractAttribute::getAsStr(). const std::string getAsStr() const override { return getAssumed() ? "noreturn" : "may-return"; @@ -2866,6 +2874,9 @@ struct AANoReturnImpl : public AANoReturn { /// See AbstractAttribute::updateImpl(Attributor &A). virtual ChangeStatus updateImpl(Attributor &A) override { + const auto &WillReturnAA = A.getAAFor(*this, getIRPosition()); + if (WillReturnAA.isKnownWillReturn()) + return indicatePessimisticFixpoint(); auto CheckForNoReturn = [](Instruction &) { return false; }; if (!A.checkForAllInstructions(CheckForNoReturn, *this, {(unsigned)Instruction::Ret})) @@ -2885,14 +2896,6 @@ struct AANoReturnFunction final : AANoReturnImpl { struct AANoReturnCallSite final : AANoReturnImpl { AANoReturnCallSite(const IRPosition &IRP) : AANoReturnImpl(IRP) {} - /// See AbstractAttribute::initialize(...). - void initialize(Attributor &A) override { - AANoReturnImpl::initialize(A); - Function *F = getAssociatedFunction(); - if (!F) - indicatePessimisticFixpoint(); - } - /// See AbstractAttribute::updateImpl(...). ChangeStatus updateImpl(Attributor &A) override { // TODO: Once we have call site specific value information we can provide -- cgit v1.2.3