diff options
Diffstat (limited to 'llvm/lib/CodeGen/LocalStackSlotAllocation.cpp')
-rw-r--r-- | llvm/lib/CodeGen/LocalStackSlotAllocation.cpp | 60 |
1 files changed, 51 insertions, 9 deletions
diff --git a/llvm/lib/CodeGen/LocalStackSlotAllocation.cpp b/llvm/lib/CodeGen/LocalStackSlotAllocation.cpp index 80a6da0f93b..f521548b213 100644 --- a/llvm/lib/CodeGen/LocalStackSlotAllocation.cpp +++ b/llvm/lib/CodeGen/LocalStackSlotAllocation.cpp @@ -17,12 +17,14 @@ #define DEBUG_TYPE "localstackalloc" #include "llvm/CodeGen/Passes.h" #include "llvm/ADT/STLExtras.h" +#include "llvm/ADT/SetVector.h" #include "llvm/ADT/SmallSet.h" #include "llvm/ADT/Statistic.h" #include "llvm/CodeGen/MachineFrameInfo.h" #include "llvm/CodeGen/MachineFunction.h" #include "llvm/CodeGen/MachineFunctionPass.h" #include "llvm/CodeGen/MachineRegisterInfo.h" +#include "llvm/CodeGen/StackProtector.h" #include "llvm/IR/Constants.h" #include "llvm/IR/DerivedTypes.h" #include "llvm/IR/Instructions.h" @@ -60,18 +62,27 @@ namespace { class LocalStackSlotPass: public MachineFunctionPass { SmallVector<int64_t,16> LocalOffsets; + /// StackObjSet - A set of stack object indexes + typedef SmallSetVector<int, 8> StackObjSet; void AdjustStackOffset(MachineFrameInfo *MFI, int FrameIdx, int64_t &Offset, bool StackGrowsDown, unsigned &MaxAlign); + void AssignProtectedObjSet(const StackObjSet &UnassignedObjs, + SmallSet<int, 16> &ProtectedObjs, + MachineFrameInfo *MFI, bool StackGrowsDown, + int64_t &Offset, unsigned &MaxAlign); void calculateFrameObjectOffsets(MachineFunction &Fn); bool insertFrameReferenceRegisters(MachineFunction &Fn); public: static char ID; // Pass identification, replacement for typeid - explicit LocalStackSlotPass() : MachineFunctionPass(ID) { } + explicit LocalStackSlotPass() : MachineFunctionPass(ID) { + initializeLocalStackSlotPassPass(*PassRegistry::getPassRegistry()); + } bool runOnMachineFunction(MachineFunction &MF); virtual void getAnalysisUsage(AnalysisUsage &AU) const { AU.setPreservesCFG(); + AU.addRequired<StackProtector>(); MachineFunctionPass::getAnalysisUsage(AU); } @@ -81,8 +92,12 @@ namespace { char LocalStackSlotPass::ID = 0; char &llvm::LocalStackSlotAllocationID = LocalStackSlotPass::ID; -INITIALIZE_PASS(LocalStackSlotPass, "localstackalloc", - "Local Stack Slot Allocation", false, false) +INITIALIZE_PASS_BEGIN(LocalStackSlotPass, "localstackalloc", + "Local Stack Slot Allocation", false, false) +INITIALIZE_PASS_DEPENDENCY(StackProtector) +INITIALIZE_PASS_END(LocalStackSlotPass, "localstackalloc", + "Local Stack Slot Allocation", false, false) + bool LocalStackSlotPass::runOnMachineFunction(MachineFunction &MF) { MachineFrameInfo *MFI = MF.getFrameInfo(); @@ -145,6 +160,22 @@ void LocalStackSlotPass::AdjustStackOffset(MachineFrameInfo *MFI, ++NumAllocations; } +/// AssignProtectedObjSet - Helper function to assign large stack objects (i.e., +/// those required to be close to the Stack Protector) to stack offsets. +void LocalStackSlotPass::AssignProtectedObjSet(const StackObjSet &UnassignedObjs, + SmallSet<int, 16> &ProtectedObjs, + MachineFrameInfo *MFI, + bool StackGrowsDown, int64_t &Offset, + unsigned &MaxAlign) { + + for (StackObjSet::const_iterator I = UnassignedObjs.begin(), + E = UnassignedObjs.end(); I != E; ++I) { + int i = *I; + AdjustStackOffset(MFI, i, Offset, StackGrowsDown, MaxAlign); + ProtectedObjs.insert(i); + } +} + /// calculateFrameObjectOffsets - Calculate actual frame offsets for all of the /// abstract stack objects. /// @@ -156,11 +187,13 @@ void LocalStackSlotPass::calculateFrameObjectOffsets(MachineFunction &Fn) { TFI.getStackGrowthDirection() == TargetFrameLowering::StackGrowsDown; int64_t Offset = 0; unsigned MaxAlign = 0; + StackProtector *SP = &getAnalysis<StackProtector>(); // Make sure that the stack protector comes before the local variables on the // stack. - SmallSet<int, 16> LargeStackObjs; + SmallSet<int, 16> ProtectedObjs; if (MFI->getStackProtectorIndex() >= 0) { + StackObjSet LargeArrayObjs; AdjustStackOffset(MFI, MFI->getStackProtectorIndex(), Offset, StackGrowsDown, MaxAlign); @@ -170,12 +203,21 @@ void LocalStackSlotPass::calculateFrameObjectOffsets(MachineFunction &Fn) { continue; if (MFI->getStackProtectorIndex() == (int)i) continue; - if (!MFI->MayNeedStackProtector(i)) - continue; - AdjustStackOffset(MFI, i, Offset, StackGrowsDown, MaxAlign); - LargeStackObjs.insert(i); + switch (SP->getSSPLayout(MFI->getObjectAllocation(i))) { + case StackProtector::SSPLK_None: + case StackProtector::SSPLK_SmallArray: + case StackProtector::SSPLK_AddrOf: + continue; + case StackProtector::SSPLK_LargeArray: + LargeArrayObjs.insert(i); + continue; + } + llvm_unreachable("Unexpected SSPLayoutKind."); } + + AssignProtectedObjSet(LargeArrayObjs, ProtectedObjs, MFI, StackGrowsDown, + Offset, MaxAlign); } // Then assign frame offsets to stack objects that are not used to spill @@ -185,7 +227,7 @@ void LocalStackSlotPass::calculateFrameObjectOffsets(MachineFunction &Fn) { continue; if (MFI->getStackProtectorIndex() == (int)i) continue; - if (LargeStackObjs.count(i)) + if (ProtectedObjs.count(i)) continue; AdjustStackOffset(MFI, i, Offset, StackGrowsDown, MaxAlign); |