diff options
Diffstat (limited to 'contrib/llvm/lib/Transforms/IPO/FunctionAttrs.cpp')
-rw-r--r-- | contrib/llvm/lib/Transforms/IPO/FunctionAttrs.cpp | 86 |
1 files changed, 52 insertions, 34 deletions
diff --git a/contrib/llvm/lib/Transforms/IPO/FunctionAttrs.cpp b/contrib/llvm/lib/Transforms/IPO/FunctionAttrs.cpp index 60e5f06..8174df9 100644 --- a/contrib/llvm/lib/Transforms/IPO/FunctionAttrs.cpp +++ b/contrib/llvm/lib/Transforms/IPO/FunctionAttrs.cpp @@ -18,7 +18,6 @@ // //===----------------------------------------------------------------------===// -#define DEBUG_TYPE "functionattrs" #include "llvm/Transforms/IPO.h" #include "llvm/ADT/SCCIterator.h" #include "llvm/ADT/SetVector.h" @@ -29,12 +28,14 @@ #include "llvm/Analysis/CallGraphSCCPass.h" #include "llvm/Analysis/CaptureTracking.h" #include "llvm/IR/GlobalVariable.h" +#include "llvm/IR/InstIterator.h" #include "llvm/IR/IntrinsicInst.h" #include "llvm/IR/LLVMContext.h" -#include "llvm/Support/InstIterator.h" #include "llvm/Target/TargetLibraryInfo.h" using namespace llvm; +#define DEBUG_TYPE "functionattrs" + STATISTIC(NumReadNone, "Number of functions marked readnone"); STATISTIC(NumReadOnly, "Number of functions marked readonly"); STATISTIC(NumNoCapture, "Number of arguments marked nocapture"); @@ -46,12 +47,12 @@ STATISTIC(NumAnnotated, "Number of attributes added to library functions"); namespace { struct FunctionAttrs : public CallGraphSCCPass { static char ID; // Pass identification, replacement for typeid - FunctionAttrs() : CallGraphSCCPass(ID), AA(0) { + FunctionAttrs() : CallGraphSCCPass(ID), AA(nullptr) { initializeFunctionAttrsPass(*PassRegistry::getPassRegistry()); } // runOnSCC - Analyze the SCC, performing the transformation if possible. - bool runOnSCC(CallGraphSCC &SCC); + bool runOnSCC(CallGraphSCC &SCC) override; // AddReadAttrs - Deduce readonly/readnone attributes for the SCC. bool AddReadAttrs(const CallGraphSCC &SCC); @@ -120,7 +121,7 @@ namespace { // call declarations. bool annotateLibraryCalls(const CallGraphSCC &SCC); - virtual void getAnalysisUsage(AnalysisUsage &AU) const { + void getAnalysisUsage(AnalysisUsage &AU) const override { AU.setPreservesCFG(); AU.addRequired<AliasAnalysis>(); AU.addRequired<TargetLibraryInfo>(); @@ -137,7 +138,7 @@ char FunctionAttrs::ID = 0; INITIALIZE_PASS_BEGIN(FunctionAttrs, "functionattrs", "Deduce function attributes", false, false) INITIALIZE_AG_DEPENDENCY(AliasAnalysis) -INITIALIZE_PASS_DEPENDENCY(CallGraph) +INITIALIZE_PASS_DEPENDENCY(CallGraphWrapperPass) INITIALIZE_PASS_DEPENDENCY(TargetLibraryInfo) INITIALIZE_PASS_END(FunctionAttrs, "functionattrs", "Deduce function attributes", false, false) @@ -160,7 +161,7 @@ bool FunctionAttrs::AddReadAttrs(const CallGraphSCC &SCC) { for (CallGraphSCC::iterator I = SCC.begin(), E = SCC.end(); I != E; ++I) { Function *F = (*I)->getFunction(); - if (F == 0) + if (!F) // External node - may write memory. Just give up. return false; @@ -319,7 +320,7 @@ namespace { ArgumentGraphNode SyntheticRoot; public: - ArgumentGraph() { SyntheticRoot.Definition = 0; } + ArgumentGraph() { SyntheticRoot.Definition = nullptr; } typedef SmallVectorImpl<ArgumentGraphNode*>::iterator iterator; @@ -342,9 +343,9 @@ namespace { ArgumentUsesTracker(const SmallPtrSet<Function*, 8> &SCCNodes) : Captured(false), SCCNodes(SCCNodes) {} - void tooManyUses() { Captured = true; } + void tooManyUses() override { Captured = true; } - bool captured(Use *U) { + bool captured(const Use *U) override { CallSite CS(U->getUser()); if (!CS.getInstruction()) { Captured = true; return true; } @@ -414,17 +415,19 @@ determinePointerReadAttrs(Argument *A, SmallSet<Use*, 32> Visited; int Count = 0; + // inalloca arguments are always clobbered by the call. + if (A->hasInAllocaAttr()) + return Attribute::None; + bool IsRead = false; // We don't need to track IsWritten. If A is written to, return immediately. - for (Value::use_iterator UI = A->use_begin(), UE = A->use_end(); - UI != UE; ++UI) { + for (Use &U : A->uses()) { if (Count++ >= 20) return Attribute::None; - Use *U = &UI.getUse(); - Visited.insert(U); - Worklist.push_back(U); + Visited.insert(&U); + Worklist.push_back(&U); } while (!Worklist.empty()) { @@ -437,25 +440,38 @@ determinePointerReadAttrs(Argument *A, case Instruction::GetElementPtr: case Instruction::PHI: case Instruction::Select: + case Instruction::AddrSpaceCast: // The original value is not read/written via this if the new value isn't. - for (Instruction::use_iterator UI = I->use_begin(), UE = I->use_end(); - UI != UE; ++UI) { - Use *U = &UI.getUse(); - if (Visited.insert(U)) - Worklist.push_back(U); - } + for (Use &UU : I->uses()) + if (Visited.insert(&UU)) + Worklist.push_back(&UU); break; case Instruction::Call: case Instruction::Invoke: { + bool Captures = true; + + if (I->getType()->isVoidTy()) + Captures = false; + + auto AddUsersToWorklistIfCapturing = [&] { + if (Captures) + for (Use &UU : I->uses()) + if (Visited.insert(&UU)) + Worklist.push_back(&UU); + }; + CallSite CS(I); - if (CS.doesNotAccessMemory()) + if (CS.doesNotAccessMemory()) { + AddUsersToWorklistIfCapturing(); continue; + } Function *F = CS.getCalledFunction(); if (!F) { if (CS.onlyReadsMemory()) { IsRead = true; + AddUsersToWorklistIfCapturing(); continue; } return Attribute::None; @@ -470,6 +486,7 @@ determinePointerReadAttrs(Argument *A, "More params than args in non-varargs call."); return Attribute::None; } + Captures &= !CS.doesNotCapture(A - B); if (SCCNodes.count(AI)) continue; if (!CS.onlyReadsMemory() && !CS.onlyReadsMemory(A - B)) @@ -478,6 +495,7 @@ determinePointerReadAttrs(Argument *A, IsRead = true; } } + AddUsersToWorklistIfCapturing(); break; } @@ -521,7 +539,7 @@ bool FunctionAttrs::AddArgumentAttrs(const CallGraphSCC &SCC) { for (CallGraphSCC::iterator I = SCC.begin(), E = SCC.end(); I != E; ++I) { Function *F = (*I)->getFunction(); - if (F == 0) + if (!F) // External node - only a problem for arguments that we pass to it. continue; @@ -599,9 +617,8 @@ bool FunctionAttrs::AddArgumentAttrs(const CallGraphSCC &SCC) { // made. If the definition doesn't have a 'nocapture' attribute by now, it // captures. - for (scc_iterator<ArgumentGraph*> I = scc_begin(&AG), E = scc_end(&AG); - I != E; ++I) { - std::vector<ArgumentGraphNode*> &ArgumentSCC = *I; + for (scc_iterator<ArgumentGraph*> I = scc_begin(&AG); !I.isAtEnd(); ++I) { + const std::vector<ArgumentGraphNode *> &ArgumentSCC = *I; if (ArgumentSCC.size() == 1) { if (!ArgumentSCC[0]->Definition) continue; // synthetic root node @@ -617,8 +634,8 @@ bool FunctionAttrs::AddArgumentAttrs(const CallGraphSCC &SCC) { } bool SCCCaptured = false; - for (std::vector<ArgumentGraphNode*>::iterator I = ArgumentSCC.begin(), - E = ArgumentSCC.end(); I != E && !SCCCaptured; ++I) { + for (auto I = ArgumentSCC.begin(), E = ArgumentSCC.end(); + I != E && !SCCCaptured; ++I) { ArgumentGraphNode *Node = *I; if (Node->Uses.empty()) { if (!Node->Definition->hasNoCaptureAttr()) @@ -630,13 +647,12 @@ bool FunctionAttrs::AddArgumentAttrs(const CallGraphSCC &SCC) { SmallPtrSet<Argument*, 8> ArgumentSCCNodes; // Fill ArgumentSCCNodes with the elements of the ArgumentSCC. Used for // quickly looking up whether a given Argument is in this ArgumentSCC. - for (std::vector<ArgumentGraphNode*>::iterator I = ArgumentSCC.begin(), - E = ArgumentSCC.end(); I != E; ++I) { + for (auto I = ArgumentSCC.begin(), E = ArgumentSCC.end(); I != E; ++I) { ArgumentSCCNodes.insert((*I)->Definition); } - for (std::vector<ArgumentGraphNode*>::iterator I = ArgumentSCC.begin(), - E = ArgumentSCC.end(); I != E && !SCCCaptured; ++I) { + for (auto I = ArgumentSCC.begin(), E = ArgumentSCC.end(); + I != E && !SCCCaptured; ++I) { ArgumentGraphNode *N = *I; for (SmallVectorImpl<ArgumentGraphNode*>::iterator UI = N->Uses.begin(), UE = N->Uses.end(); UI != UE; ++UI) { @@ -723,6 +739,7 @@ bool FunctionAttrs::IsFunctionMallocLike(Function *F, // Extend the analysis by looking upwards. case Instruction::BitCast: case Instruction::GetElementPtr: + case Instruction::AddrSpaceCast: FlowsToReturn.insert(RVI->getOperand(0)); continue; case Instruction::Select: { @@ -775,7 +792,7 @@ bool FunctionAttrs::AddNoAliasAttrs(const CallGraphSCC &SCC) { for (CallGraphSCC::iterator I = SCC.begin(), E = SCC.end(); I != E; ++I) { Function *F = (*I)->getFunction(); - if (F == 0) + if (!F) // External node - skip it; return false; @@ -1649,6 +1666,7 @@ bool FunctionAttrs::inferPrototypeAttributes(Function &F) { setDoesNotThrow(F); setDoesNotCapture(F, 1); setDoesNotCapture(F, 2); + break; default: // Didn't mark any attributes. return false; @@ -1667,7 +1685,7 @@ bool FunctionAttrs::annotateLibraryCalls(const CallGraphSCC &SCC) { for (CallGraphSCC::iterator I = SCC.begin(), E = SCC.end(); I != E; ++I) { Function *F = (*I)->getFunction(); - if (F != 0 && F->isDeclaration()) + if (F && F->isDeclaration()) MadeChange |= inferPrototypeAttributes(*F); } |