diff options
Diffstat (limited to 'llvm/lib/Analysis/ModuleSummaryAnalysis.cpp')
| -rw-r--r-- | llvm/lib/Analysis/ModuleSummaryAnalysis.cpp | 26 |
1 files changed, 24 insertions, 2 deletions
diff --git a/llvm/lib/Analysis/ModuleSummaryAnalysis.cpp b/llvm/lib/Analysis/ModuleSummaryAnalysis.cpp index d808148..4039a44 100644 --- a/llvm/lib/Analysis/ModuleSummaryAnalysis.cpp +++ b/llvm/lib/Analysis/ModuleSummaryAnalysis.cpp @@ -234,6 +234,26 @@ static bool isNonVolatileStore(const Instruction *I) { return false; } +// Returns true if `F` must be an unreachable function. +// +// Note if this helper function returns true, `F` is guaranteed +// to be unreachable; if it returns false, `F` might still +// be unreachable but not covered by this helper function. +static bool mustBeUnreachableFunction(const Function &F) { + if (!F.empty()) { + const BasicBlock &entryBlock = F.getEntryBlock(); + // A function must be unreachable if its entry block + // ends with an 'unreachable'. + if (!entryBlock.empty()) { + const Instruction *inst = &(*entryBlock.rbegin()); + if (inst->getOpcode() == Instruction::Unreachable) { + return true; + } + } + } + return false; +} + static void computeFunctionSummary( ModuleSummaryIndex &Index, const Module &M, const Function &F, BlockFrequencyInfo *BFI, ProfileSummaryInfo *PSI, DominatorTree &DT, @@ -488,7 +508,8 @@ static void computeFunctionSummary( // Don't try to import functions with noinline attribute. F.getAttributes().hasFnAttr(Attribute::NoInline), F.hasFnAttribute(Attribute::AlwaysInline), - F.hasFnAttribute(Attribute::NoUnwind), MayThrow, HasUnknownCall}; + F.hasFnAttribute(Attribute::NoUnwind), MayThrow, HasUnknownCall, + mustBeUnreachableFunction(F)}; std::vector<FunctionSummary::ParamAccess> ParamAccesses; if (auto *SSI = GetSSICallback(F)) ParamAccesses = SSI->getParamAccesses(Index); @@ -737,7 +758,8 @@ ModuleSummaryIndex llvm::buildModuleSummaryIndex( F->hasFnAttribute(Attribute::AlwaysInline), F->hasFnAttribute(Attribute::NoUnwind), /* MayThrow */ true, - /* HasUnknownCall */ true}, + /* HasUnknownCall */ true, + /* MustBeUnreachable */ false}, /*EntryCount=*/0, ArrayRef<ValueInfo>{}, ArrayRef<FunctionSummary::EdgeTy>{}, ArrayRef<GlobalValue::GUID>{}, |